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Croup: Clinical features, evaluation, and diagnosis Author Charles R Woods, MD, MS Section Editors Sheldon L Kaplan, MD Gregory Redding, MD Deputy Editor Carrie Armsby, MD, MPH Disclosures: Charles R Woods, MD, MS Other Financial Interest: Cerexa [Epiglottitis (Data Safety Monitoring Board for pediatric trials of the antibiotic
agent ceftaroline)]. Sheldon L Kaplan, MDGrant/Research/Clinical Trial Support: Pfizer [vaccine (PCV13)]; Forest Lab [antibiotic (Ceftaroline)]; Optimer
[antibiotic (fidaxomicin)]. Consultant/Advisory Boards: Pfizer [vaccine (PCV13)]. Gregory Redding, MD Nothing to disclose. Carrie Armsby, MD,
MPH Nothing to disclose.
Contributor disclosures are reviewed for conflicts of interest by the editorial group. When found, these are addressed by vetting through a multi-level
review process, and through requirements for references to be provided to support the content. Appropriately referenced content is required of all
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All topics are updated as new evidence becomes available and our peer review process is complete. Literature review current through: Jul 2015. | This topic last updated: Feb 18, 2015.
INTRODUCTION — Croup is a respiratory illness characterized
by inspiratory stridor, cough, and hoarseness. These symptoms
result from inflammation in the larynx and subglottic airway. A
barking cough is the hallmark of croup among infants and young
children, whereas hoarseness predominates in older children
and adults. Although croup usually is a mild and self-limited
illness, significant upper airway obstruction, respiratory distress,
and, rarely, death, can occur.
The clinical features, evaluation, and diagnosis of croup will be
discussed here. The management of croup is discussed
separately. (See "Croup: Approach to
management" and "Croup: Pharmacologic and supportive
interventions".)
DEFINITIONS — The term croup has been used to describe a
variety of upper respiratory conditions in children, including
laryngitis, laryngotracheitis, laryngotracheobronchitis, bacterial
tracheitis, or spasmodic croup [1]. These terms are defined
below. In the past, the term croup also has been applied to
laryngeal diphtheria (diphtheritic or membranous croup), which
is discussed separately. (See "Epidemiology and
pathophysiology of diphtheria" and "Clinical manifestations,
diagnosis and treatment of diphtheria".)
Throughout this review, the term croup will be used to refer to
laryngotracheitis. Laryngotracheobronchitis,
laryngotracheobronchopneumonitis, bacterial tracheitis, and
spasmodic croup are designated specifically as such.
●Laryngitis refers to inflammation limited to the larynx and
manifests itself as hoarseness [2]. It usually occurs in
older children and adults and, similar to croup, is
frequently caused by a viral infection. The etiology,
management, and evaluation of other causes of
hoarseness are discussed in detail separately.
(See"Hoarseness in children: Etiology and
management" and "Hoarseness in children: Evaluation".)
●Laryngotracheitis (croup) refers to inflammation of the
larynx and trachea [2]. Although lower airway signs are
absent, the typical barking cough will be present.
●Laryngotracheobronchitis (LTB) occurs when
inflammation extends into the bronchi, resulting in lower
airway signs (eg, wheezing, crackles, air trapping,
increased tachypnea) and sometimes more severe illness
than laryngotracheitis alone [2]. This term commonly is
used interchangeably with laryngotracheitis, and the
entities are often indistinct clinically. Further extension of
inflammation into the lower airways results in
laryngotracheobronchopneumonitis, which sometimes
can be complicated by bacterial superinfection. Bacterial
superinfection can be manifest as pneumonia,
bronchopneumonia, or bacterial tracheitis.
●Bacterial tracheitis (also called bacterial croup)
describes bacterial infection of the subglottic trachea,
resulting in a thick, purulent exudate, which causes
symptoms of upper airway obstruction (picture 1). The
bronchi and lungs are typically involved, as well (ie,
bacterial tracheobronchitis). Bacterial tracheitis may occur
as a complication of viral respiratory infections (usually
those which manifest themselves as LTB or
laryngotracheobronchopneumonitis) or as a primary
bacterial infection. (See "Bacterial tracheitis in children:
Clinical features and diagnosis".)
●Spasmodic croup is characterized by the sudden onset
of inspiratory stridor at night, short duration (several
hours), and sudden cessation [2]. This is often in the
setting of a mild upper respiratory infection, but without
fever or inflammation. A striking feature of spasmodic
croup is its recurrent nature, hence the alternate
descriptive term, "frequently recurrent croup". Because of
some clinical overlap with atopic diseases, it is sometimes
referred to as "allergic croup".
We consider "spasmodic croup" to be distinct from
"atypical croup," although the terms are sometimes used
interchangeably. Atypical croup may be defined as
recurrent episodes of croup-like symptoms occurring
beyond the typical age range of six months to three years
for "viral croup" or recurrent episodes that do not appear
to be simple "spasmodic croup" [3].
ETIOLOGY — Croup is usually caused by viruses. Bacterial
infection may occur secondarily, as described above.
Parainfluenza virus type 1 is the most common cause of acute
laryngotracheitis, especially the fall and winter epidemics [4-6].
Parainfluenza type 2 sometimes causes croup outbreaks, but
usually with milder disease than type 1. Parainfluenza type 3
causes sporadic cases of croup that often are more severe than
those due to types 1 and 2. In multicenter surveillance of
children <5 years who were hospitalized with febrile or acute
respiratory illnesses, 43 percent of children with confirmed
parainfluenza infection were diagnosed with croup [7]. Croup
was the most common discharge diagnosis for children with
confirmed parainfluenza 1 (42 percent) and parainfluenza 2 (48
percent) infections but was only diagnosed in 11 percent of
children with confirmed parainfluenza 3 infections.
The microbiology, pathogenesis, and epidemiology of
parainfluenza infections are discussed separately.
(See "Parainfluenza viruses in children".)
A number of other viruses that typically cause lower respiratory
tract disease also can cause upper respiratory tract symptoms,
including croup, as described below [6].
●Respiratory syncytial virus (RSV) and adenoviruses are
relatively frequent causes of croup. The laryngotracheal
component of disease is usually less significant than that
of the lower airways. (See "Respiratory syncytial virus
infection: Clinical features and diagnosis", section on
'Clinical manifestations' and "Epidemiology and clinical
manifestations of adenovirus infection", section on
'Clinical presentation'.)
●Human coronavirus NL63 (HCoV-NL63), first identified
in 2004, has been implicated in croup and other
respiratory illnesses [8-10]. The prevalence of HCoV-
NL63 varies geographically. (See "Coronaviruses",
section on 'Respiratory'.)
●Measles is an important cause of croup in areas where
measles remains prevalent. (See "Clinical manifestations
and diagnosis of measles".)
●Influenza virus is a relatively uncommon cause of croup.
However, children hospitalized with influenzal croup tend
to have longer hospitalization and greater risk of
readmission for relapse of laryngeal symptoms than those
with parainfluenzal croup. (See "Seasonal influenza in
children: Clinical features and diagnosis".)
●Rhinoviruses, enteroviruses (especially Coxsackie types
A9, B4, and B5, and echovirus types 4, 11, and 21), and
herpes simplex virus are occasional causes of sporadic
cases of croup that are usually mild. (See appropriate
topic reviews).
●Metapneumoviruses cause primarily lower respiratory
tract disease similar to RSV, but upper respiratory tract
symptoms have been described in some patients [11].
(See "Human metapneumovirus infections".)
Croup also may be caused by bacteria. Mycoplasma
pneumoniae has been associated with mild cases of croup. In
addition, secondary bacterial infection may occur in children
with laryngotracheitis, laryngotracheobronchitis, or
laryngotracheobronchopneumonitis. The most common
secondary bacterial pathogens include Staphylococcus
aureus, Streptococcus pyogenes, and S. pneumoniae [1].
EPIDEMIOLOGY — Croup most commonly occurs in children 6
to 36 months of age. It is seen in younger infants (as young as
three months) and in preschool children, but it is rare beyond
age six years [1,12]. It is more common in boys, with a
male:female ratio of about 1.4:1 [1,12-14].
Family history of croup is a risk factor for croup and recurrent
croup. In a case-control study, children whose parents had a
history of croup were 3.2 times as likely to have an episode of
croup and 4.1 times as likely to have recurrent croup as children
with no parental history of croup [15]. Parental smoking, a well-
recognized risk factor for respiratory tract infections in children,
does not appear to increase the risk of croup [15,16].
(See "Secondhand smoke exposure: Effects in children",
section on 'Respiratory symptoms and illness'.)
Most cases of croup occur in the fall or early winter, with the
major incidence peaks coinciding with parainfluenza type 1
activity (often in October) and minor peaks occurring during
periods of respiratory syncytial virus or influenza virus activity.
(See "Respiratory syncytial virus infection: Clinical features and
diagnosis", section on 'Seasonality' and "Seasonal influenza in
children: Clinical features and diagnosis", section on 'Influenza
activity'.)
Emergency department (ED) visits for croup are most frequent
between 10:00 PM and 4:00 AM. However, children seen for
croup between noon and 6:00 PM are more likely to be admitted
to the hospital [4,17]. A morning peak between 7:00 AM and
11:00 AM in ED visits for croup also has been noted [14].
Hospital admissions for croup have declined steadily since the
late 1970s. In an analysis of data from the National Hospital
Discharge Surveys from 1979 through 1997, the estimated
number of annual hospitalizations for croup decreased from
48,900 to 33,500 [5]. Estimates of annual hospitalization rates
for croup caused by parainfluenza virus types 1 to 3 from 1994
to 1997 were 0.4 to 1.1 per 1000 children for children younger
than one year and 0.24 to 0.61 per 1000 children for children
between one and four years. Approximately one-half of these
hospitalizations were attributed to parainfluenza type 1.
In a six-year (1999 to 2005) population-based study, 5.6 percent
of children with a diagnosis of croup in the ED required hospital
admission. Among those discharged home, 4.4 percent had a
repeat ED visit within 48 hours [14].
PATHOGENESIS — The viruses that cause croup typically infect
the nasal and pharyngeal mucosal epithelia initially and then
spread locally along the respiratory epithelium to the larynx and
trachea.
The anatomic hallmark of croup is narrowing of the trachea in
the subglottic region. This portion of the trachea is surrounded
by a firm cartilaginous ring such that any inflammation results in
narrowing of the airway. In addition to this "fixed" obstruction,
dynamic obstruction of the extrathoracic trachea below the
cartilaginous ring may occur when the child struggles, cries, or
becomes agitated. The dynamic obstruction occurs as a result
of the combination of high negative pressure in the distal
extrathoracic trachea and the floppiness of the tracheal wall in
children.
Laryngoscopic evaluation of patients during acute
laryngotracheitis shows redness and swelling of the lateral walls
of the trachea. In severe cases, the subglottic airway may be
reduced to a diameter of 1 to 2 mm. In addition to mucosal
edema and swelling, fibrinous exudates and, occasionally,
pseudomembranes can build up on the tracheal surfaces and
contribute to airway narrowing. The vocal cords and laryngeal
tissues also can become swollen, and cord mobility may be
impaired [2,18-20]. Autopsy studies in children with
laryngotracheitis show infiltration of histiocytes, lymphocytes,
plasma cells, and neutrophils into edematous lamina propria,
submucosa, and adventitia of the larynx and trachea [21-23].
In spasmodic croup, findings on direct laryngoscopy
demonstrate noninflammatory edema [18]. This suggests that
there is no direct viral involvement of the tracheal epithelium.
Patients with bacterial tracheitis have a bacterial superinfection
that causes thick pus to develop within the lumen of the
subglottic trachea (picture 1). Ulcerations, pseudomembranes,
and microabscesses of the mucosal surface occur. The
supraglottic tissues usually are normal. (See "Bacterial
tracheitis in children: Clinical features and diagnosis", section
on 'Pathogenesis and pathology'.)
Host factors — Only a small fraction of children with
parainfluenza virus infections develop overt croup. This
suggests that host (or genetic) factors play a role in the
pathogenesis. Host factors that may contribute to the
development of croup include functional or anatomic
susceptibility to upper airway narrowing, variations in immune
response, and predisposition to atopy [14].
Underlying host factors that predispose to clinically significant
narrowing of the upper airway include:
●Anatomic narrowing of the airway, from etiologies such
as subglottic stenosis, laryngeal webs, tracheomalacia,
laryngomalacia, laryngeal clefts, or subglottic
hemangiomas [3]
●Hyperactive airways, perhaps aggravated by atopy or
gastroesophageal reflux, as suggested in some children
with spasmodic croup or recurrent croup [24-26]
●Acquired airway narrowing from respiratory tract
papillomas (human papillomavirus), post-intubation
scarring, or irritation from aspirations associated with
gastroesophageal reflux
The potential role of the immune response was demonstrated in
studies that demonstrated increased production of
parainfluenza virus-specific IgE and increased
lymphoproliferative response to parainfluenza virus antigen, and
diminished histamine-induced suppression of lymphocyte
transformation responses to parainfluenza virus in children with
parainfluenza virus and croup compared with those with
parainfluenza virus without croup [27,28].
CLINICAL PRESENTATION — The clinical presentation of croup
depends upon the specific croup syndrome and the degree of
upper airway obstruction. Although croup usually is a mild and
self-limited illness, specific features of the history and physical
examination identify children who are seriously ill or at risk for
rapid progression of disease. (See 'Evaluation' below.)
Laryngotracheitis — Laryngotracheitis typically occurs in children
three months to three years of age [2]. The onset of symptoms
is usually gradual, beginning with nasal irritation, congestion,
and coryza. Symptoms generally progress over 12 to 48 hours
to include fever, hoarseness, barking cough, and stridor.
Respiratory distress increases as upper airway obstruction
becomes more severe. Rapid progression or signs of lower
airway involvement suggests a more serious illness. Cough
usually resolves within three days [29]; other symptoms may
persist for seven days with a gradual return to normal [2].
Deviations from this expected course should prompt
consideration of diagnoses other than laryngotracheitis.
(See 'Differential diagnosis' below.)
The degree of upper airway obstruction is evident on physical
examination, as described below. In mild cases, the child is
hoarse and has nasal congestion. There is minimal, if any,
pharyngitis. As airway obstruction progresses, stridor develops,
and there may be mild tachypnea with a prolonged inspiratory
phase. The presence of stridor is a key element in the
assessment of severity. Stridor at rest is a sign of significant
upper airway obstruction. As upper airway obstruction
progresses, the child may become restless or anxious.
(See 'Severity assessment' below.)
When airway obstruction becomes severe, suprasternal,
subcostal, and intercostal retractions may be seen. Breath
sounds can be diminished. Agitation, which generally is
accompanied by increased inspiratory effort, exacerbates the
subglottic narrowing by creating negative pressure in the
airway. This can lead to further respiratory distress and
agitation.
Hypoxia and cyanosis can develop, as can respiratory fatigue
from sustained increased respiratory effort. High respiratory
rates also tend to correlate with the presence of hypoxia.
Without intervention, the hypoxia or fatigue can sometimes lead
to death.
Spasmodic croup — Spasmodic croup also occurs in children
three months to three years of age [2]. In contrast to
laryngotracheitis, spasmodic croup always occurs at night; the
duration of symptoms is short, often with symptoms subsiding
by the time of presentation for medical attention; and the onset
and cessation of symptoms are abrupt. Fever is typically
absent, but mild upper respiratory tract symptoms (eg, coryza)
may be present. Episodes can recur within the same night and
for two to four successive evenings [30]. A striking feature of
spasmodic croup is its recurrent nature, hence the alternate
descriptive term, "frequently recurrent croup". There may be a
familial predisposition to spasmodic croup, and it may be more
common in children with a family history of allergies [24].
Early in the clinical course, spasmodic croup may be difficult to
distinguish from laryngotracheitis. As the course progresses,
the episodic nature of spasmodic croup and relative wellness of
the child between attacks differentiate it from classic croup, in
which the symptoms are continuous.
Although the initial presentation can be dramatic, the clinical
course is usually benign. Symptoms are almost always relieved
by comforting the anxious child and administering humidified
air. Rarely, children may benefit from treatment with
corticosteroids and/or nebulized epinephrine [31]. Other
therapies generally are not indicated. (See "Croup: Approach to
management".)
Bacterial tracheitis — Bacterial tracheitis may present as a
primary or secondary infection [32]. In primary infection, there is
acute onset of symptoms of upper airway obstruction with fever
and toxic appearance. In secondary infection, there is marked
worsening during the clinical course of viral laryngotracheitis,
with high fever, toxic appearance, and increasing respiratory
distress secondary to tracheal obstruction from purulent
secretions. In both of these presentations, signs of lower airway
disease, such as crackles and wheezes, may be present.
However, the upper airway obstruction is the more clinically
significant manifestation [2,33]. (See "Bacterial tracheitis in
children: Clinical features and diagnosis", section on 'Clinical
features'.)
Recurrent croup — A child who has had recurrent episodes of
classic viral croup may have an underlying condition that
predisposes him or her to develop clinically significant
narrowing of the upper airway. Recurrent episodes of croup-like
symptoms occurring outside the typical age range for "viral
croup" (ie, six months to three years) and recurrent episodes
that do not appear to be simple "spasmodic croup" should raise
suspicion for large airway lesions, gastroesophageal reflux or
eosinophilic esophagitis, or atopic conditions [3,34-38].
Children with recurrent croup may require radiographic
evaluation or bronchoscopy. (See 'Host factors' above
and 'Imaging' below.)
EVALUATION
Overview — The evaluation of children with suspected croup has
several objectives, including prompt identification of patients
with significant upper airway obstruction or at risk for rapid
progression of upper airway obstruction. In addition, there are
some conditions with presentations similar to that of croup that
require specific evaluationsand/or interventions; these too must
be promptly identified. (See 'Differential diagnosis' below.)
During the evaluation, efforts should be made to make the child
as comfortable as possible. The increased inspiratory effort that
accompanies anxiety and fear in young children can exacerbate
subglottic narrowing, further diminishing air exchange and
oxygenation. (See 'Pathogenesis' above.)
Rapid assessment and initial management — Rapid assessment
of general appearance (including the presence of stridor at
rest), vital signs, pulse oximetry, airway stability, and mental
status is necessary to identify children with severe respiratory
distress and/or impending respiratory failure. (See "Croup:
Approach to management", section on 'Respiratory care'.)
Endotracheal intubation is required in less than 1 percent of
children with croup who are seen in the emergency department.
However, the need for endotracheal intubation should be
anticipated in children with progressive respiratory failure so
that it can be performed in as controlled a setting as possible.
Respiratory failure is heralded by the following signs [1,39,40]:
●Fatigue and listlessness
●Marked retractions (although retractions may decrease
with increased obstruction and decreased air entry)
●Decreased or absent breath sounds
●Depressed level of consciousness
●Tachycardia out of proportion to fever
●Cyanosis or pallor
A tracheal tube that is 0.5 to 1 mm smaller than would typically
be used may be required. (See "Emergency endotracheal
intubation in children", section on 'Endotracheal tube'.)
In addition to establishment of an airway, children who have
severe respiratory distress require immediate pharmacologic
treatment, including administration of nebulizedepinephrine and
systemic or nebulized corticosteroids. (See "Croup: Approach to
management", section on 'Moderate to severe croup'.)
Once control of the airway is established and pharmacologic
treatment, if necessary, is under way, the remainder of the
evaluation can proceed.
History — The history should include a description of the onset,
duration, and progression of symptoms. Factors that are
associated with increased severity of illness include:
●Sudden onset of symptoms
●Rapidly progressing symptoms (ie, symptoms of upper
airway obstruction after fewer than 12 hours of illness)
●Previous episodes of croup
●Underlying abnormality of the upper airway
●Medical conditions that predispose to respiratory failure
(eg, neuromuscular disorders)
Aspects of the history that are helpful in distinguishing croup
from other causes of acute upper airway obstruction include
[1,41]:
●Fever – The absence of fever from onset of symptoms to
the time of presentation is suggestive of spasmodic croup
or a noninfectious etiology (eg, foreign body aspiration or
ingestion, acute angioneurotic edema).
●Hoarseness and barking cough – Hoarseness and
barking cough, characteristic findings in croup, are
typically absent in children with acute epiglottitis, foreign
body aspiration, and angioneurotic edema.
●Difficulty swallowing – Difficulty swallowing may occur in
acute epiglottitis and foreign body aspiration. A large
ingested foreign body may lodge in the upper esophagus,
where it distorts and narrows the upper trachea, thus
mimicking the croup syndrome (including barking cough
and inspiratory stridor).
●Drooling – Drooling may occur in children with
peritonsillar or retropharyngeal abscesses,
retropharyngeal cellulitis, and epiglottitis. In an
observational study, drooling was present in
approximately 80 percent of children with epiglottitis, but
only 10 percent of those with croup [41].
●Throat pain – Complaints of dysphagia and sore throat
are more common in children with epiglottitis than croup
(approximately 60 to 70 percent versus <10 percent) [41].
The differential diagnosis of croup is discussed in greater detail
below. (See 'Differential diagnosis' below.)
Examination — The objectives of the examination of the child
with croup include assessment of severity of upper airway
obstruction and exclusion of other infectious and non-infectious
causes of acute upper airway obstruction, both of which are
necessary in making management decisions.
The initial examination often can be accomplished by observing
the child in a comfortable position with the caretaker. Every
effort should be made to measure the child's weight and vital
signs.
Aspects of the examination that are helpful in assessing the
degree of upper airway obstruction and severity of illness
include:
●Overall appearance – Is the child comfortable and
interactive, anxious and quiet, or obtunded? Is there
stridor at rest? Stridor at rest is a sign of significant upper
airway obstruction. Children with significant upper airway
obstruction may prefer to sit up and lean forward in a
"sniffing" position (neck is mildly flexed, and head is mildly
extended). This position tends to improve the patency of
the upper airway.
●Quality of the voice – Does the child have a hoarse or
diminished cry? Is the voice muffled? A muffled "hot
potato" voice is suggestive of epiglottitis, retropharyngeal
abscess, or peritonsillar abscess.
●Degree of respiratory distress – Signs of respiratory
distress include tachypnea, hypoxemia, and increased
work of breathing (intercostal, subcostal, or suprasternal
retractions; nasal flaring; grunting; use of accessory
muscles)
●Tidal volume – Does there appear to be good chest
expansion with inspiration, indicating adequate air entry?
●Lung examination – Are there abnormal respiratory
sounds during inspiration or expiration? Inspiratory stridor
indicates upper airway obstruction, whereas expiratory
wheezing is a sign of lower airway obstruction. If there is
stridor, is it present at rest or only with agitation? As
discussed above, stridor at rest is a sign of significant
upper airway obstruction. Stridor will be more obvious on
auscultation, since the inspiratory noise is transmitted
through the chest. The presence of crackles (rales) also
suggests lower respiratory tract involvement (eg,
laryngotracheobronchitis,
laryngotracheobronchopneumonitis, or bacterial
tracheitis).
●Assessment of hydration status – Decreased oral intake
and increased insensible losses from fever and
tachypnea may result in dehydration. (See "Clinical
assessment and diagnosis of hypovolemia (dehydration)
in children".)
These aspects of the examination are often used in clinical
scoring systems to evaluate the severity of illness and/or in
making decisions regarding the need for hospital admission.
(See 'Severity assessment' below and "Croup: Approach to
management", section on 'Observation and disposition'.)
Components of the examination that are useful in distinguishing
croup from other causes of acute upper airway obstruction
include [39,41]:
●Preferred posture – Children with epiglottitis usually
prefer to sit up in the "tripod" or "sniffing position" (picture
2A-B).
●Examination of the oropharynx for the following signs:
•Cherry red, swollen epiglottis, suggestive of
epiglottitis
•Pharyngitis, typically minimal in laryngotracheitis,
may be more pronounced in epiglottitis or laryngitis
•Excessive salivation, suggestive of acute
epiglottitis, peritonsillar abscess, or retropharyngeal
abscess
•Diphtheritic membrane
•Tonsillar asymmetry or deviation of the uvula
suggestive of peritonsillar abscess
•Midline or unilateral swelling of the posterior
pharyngeal wall suggestive of retropharyngeal
abscess
Concerns have been raised about safety of
examining the pharynx in children with upper airway
obstruction and possible epiglottitis since such
efforts have been reported to precipitate
cardiorespiratory arrest. However, in two series,
each including more than 200 patients with
epiglottitis or viral croup, direct examination of the
oropharynx was not associated with sudden clinical
deterioration [32,42].
●Examination of the cervical lymph nodes, which can be
enlarged in patients with retropharyngeal or peritonsillar
abscesses.
●Other physical findings may be present, depending on
the particular inciting virus. As an example, rash,
conjunctivitis, exudative pharyngitis, and adenopathy are
suggestive of adenovirus infection.
●Otitis media (acute or with effusion) may be present as a
primary viral or secondary bacterial process.
The differential diagnosis of croup is discussed in greater detail
below. (See 'Differential diagnosis' below.)
Severity assessment — The severity of croup is often
determined by the clinical scoring systems. Although there are a
number of validated croup scoring systems, the Westley croup
score [43] has been the most extensively studied; it is described
below. No matter which system is used to assess severity, the
presence of chest wall retractions and stridor at rest are the two
critical clinical features.
The elements of the Westley croup score describe key features
of the physical examination [43]. Each element is assigned a
score, as illustrated below:
●Level of consciousness: Normal, including sleep = 0;
disoriented = 5
●Cyanosis: None = 0; with agitation = 4; at rest = 5
●Stridor: None = 0; with agitation = 1; at rest = 2
●Air entry: Normal = 0; decreased = 1; markedly
decreased = 2
●Retractions: None = 0; mild = 1; moderate = 2; severe =
3
Mild croup is defined by a Westley croup score of ≤2. Typically,
these children have a barking cough and hoarse cry, but no
stridor at rest. Children with mild croup may have stridor when
upset or crying (ie, agitated) and either no, or only mild,
chest wall/subcostal retractions [1,39].
Moderate croup is defined by a Westley croup score of 3 to 7.
Children with moderate croup have stridor at rest, at least mild
retractions, and may have other symptoms or signs of
respiratory distress, but little or no agitation [1,39].
Severe croup is defined by a Westley croup score of ≥8.
Children with severe croup have significant stridor at rest,
although stridor may decrease with worsening upper airway
obstruction and decreased air entry [1,39]. Retractions are
severe (including indrawing of the sternum) and the child may
appear anxious, agitated, or fatigued. Prompt recognition and
treatment of children with severe croup are paramount.
Imaging
Indications — Radiographic confirmation of acute
laryngotracheitis is not required in the vast majority of children
with croup. Radiographic evaluation of the chestand/or upper
trachea is indicated if the diagnosis is in question, the course is
atypical, an inhaled or swallowed foreign body is suspected
(although the majority are not radio-opaque), croup is
recurrent, and/or there is a failure to respond as expected to
therapeutic interventions. (See 'Differential diagnosis' below
and "Croup: Approach to management".)
Findings — In children with croup, a posterior-anterior chest
radiograph demonstrates subglottic narrowing, commonly called
the "steeple sign" (image 1). The lateral view may demonstrate
overdistention of the hypopharynx during inspiration [44] and
subglottic haziness (image 2). The epiglottis should have a
normal appearance.
In contrast, the lateral radiograph in virtually all children with
epiglottitis demonstrates swelling of the epiglottis, sometimes
called the "thumb sign" (image 3). (See"Epiglottitis
(supraglottitis): Clinical features and diagnosis", section on
'Radiographic features'.)
The lateral radiograph in children with bacterial tracheitis may
demonstrate only nonspecific edema or intraluminal
membranes and irregularities of the tracheal wall (image 4) [45].
Laboratory studies — Laboratory studies, which are rarely
indicated in children with croup, are of limited diagnostic utility
but may help guide management in more severe cases.
Blood tests — The white blood cell (WBC) count can be low,
normal, or elevated; WBC counts >10,000 cells/microL are
common. Neutrophil or lymphocyte predominance may be
present on the differential [46,47]. The presence of a large
number of band-form neutrophils is suggestive of primary or
secondary bacterial infection. Croup is not associated with any
specific alterations in serum chemistries.
Microbiology — Confirmation of etiologic diagnosis is not
necessary for most children with croup, since croup is a self-
limited illness that usually requires only symptomatic therapy.
When an etiologic diagnosis is necessary, viral
culture and/or rapid diagnostic tests that detect viral antigens
are performed on secretions from the nasopharynx or throat.
(See 'Etiologic diagnosis' below.)
DIAGNOSIS
Clinical diagnosis — The diagnosis of croup is clinical, based on
the presence of a barking cough and stridor, especially during a
typical community epidemic of one of the causative viruses.
(See 'Etiology' above.)
Neither radiographs nor laboratory tests are necessary to make
the diagnosis. However, radiographs may be helpful in
excluding other causes if the diagnosis is in question.
(See 'Differential diagnosis' below.)
Etiologic diagnosis — Although not typically required in most
cases of croup, identification of a specific viral etiology may be
necessary to make decisions regarding isolation for patients
requiring hospitalization or for
public health/epidemiologic monitoring purposes. Testing for
influenza is indicated if the results will influence decisions
regarding treatment, prophylaxis of contacts, or performance of
other diagnostic tests; laboratory confirmation should not delay
the initiation of antiviral therapy for influenza when clinical and
seasonal considerations are compatible with influenza as the
potential etiology of croup. (See "Seasonal influenza in children:
Clinical features and diagnosis", section on 'Laboratory
diagnosis' and "Seasonal influenza in children: Prevention and
treatment with antiviral drugs", section on 'Timing of treatment'.)
Diagnosis of a specific viral etiology can be made by viral
culture of secretions from the nasopharynx or throat. Rapid
tests that detect viral antigens in these secretions are
commercially available for many respiratory viruses. The
diagnosis of specific viral infections is discussed in detail in
individual topic reviews:
●Parainfluenza (see "Parainfluenza viruses in children",
section on 'Diagnosis')
●Influenza (see "Seasonal influenza in children: Clinical
features and diagnosis", section on 'Diagnosis')
●Respiratory syncytial virus (see "Respiratory syncytial
virus infection: Clinical features and diagnosis", section on
'Laboratory diagnosis')
●Adenovirus (see "Diagnosis, treatment, and prevention
of adenovirus infection", section on 'Diagnostic tests of
choice for different adenovirus syndromes')
●Measles (see "Clinical manifestations and diagnosis of
measles", section on 'Diagnosis')
●Enteroviruses (see "Clinical manifestations and
diagnosis of enterovirus and parechovirus infections",
section on 'Laboratory diagnosis')
●Metapneumovirus (see "Human metapneumovirus
infections", section on 'Diagnosis')
●Coronavirus (see "Coronaviruses", section on
'Diagnosis')
In addition, multiplex tests, which assess the presence of
multiple agents at the same time, and PCR-based tests are
becoming more widely available [48].
DIFFERENTIAL DIAGNOSIS — The differential diagnosis of
croup includes other causes of stridor and/or respiratory
distress. The primary considerations are those with acute onset,
particularly those that may rapidly progress to complete upper
airway obstruction, and those that require specific therapy.
Underlying anatomic anomalies of the upper airway also must
be considered, since they may contribute to more severe
disease. (See 'Host factors' above.)
Important considerations include [1,12]:
●Acute epiglottitis
●Peritonsillar and retropharyngeal abscesses
●Foreign body aspiration or ingestion
●Allergic reaction
●Acute angioneurotic edema
●Upper airway injury
●Congenital anomalies of the upper airway
●Laryngeal diphtheria (see "Clinical manifestations,
diagnosis and treatment of diphtheria")
Acute epiglottitis – Epiglottitis, which is rare in the era of
vaccination against Haemophilus influenzae type b, is
distinguished from croup by the absence of barking cough and
the presence of anxiety that is out of proportion to the degree of
respiratory distress. Onset of symptoms is rapid, and because
of the associated bacteremia, the child is highly febrile, pale,
toxic, and ill-appearing. Because of the swollen epiglottis, the
child will have difficulty swallowing and is often drooling. The
children usually prefer to sit up and seldom have observed
cough [41]. Epiglottitis occurs infrequently, and there is no
predominant etiologic pathogen. (See "Epiglottitis
(supraglottitis): Clinical features and diagnosis".)
Peritonsillar or retropharyngeal abscesses – Children with deep
neck space abscesses, cellulitis of the cervical prevertebral
tissues, or other painful infections of the oropharynx may
present with drooling and neck extension and varying degrees
of toxicity. Barking cough is usually absent. (See "Peritonsillar
cellulitis and abscess", section on
'Presentation' and "Retropharyngeal infections in children",
section on 'Presentation'.)
Foreign body – In foreign body aspiration, there often is a history
of the sudden onset of choking and symptoms of upper airway
obstruction in a previously healthy child. If an inhaled foreign
body lodges in the larynx, it will produce hoarseness and stridor.
If a large foreign body is swallowed, it may lodge in the upper
esophagus, resulting in distortion of the adjacent soft
extrathoracic trachea, producing a barking cough and
inspiratory stridor. (See "Airway foreign bodies in
children" and "Foreign bodies of the esophagus and
gastrointestinal tract in children".)
Allergic reaction or acute angioneurotic edema – Allergic
reaction or acute angioneurotic edema has rapid onset without
antecedent cold symptoms or fever. The primary manifestations
are swelling of the lips and tongue, urticarial rash, dysphagia
without hoarseness, and sometimes inspiratory stridor [1,12].
There may be a history of allergy or a previous attack. (See "An
overview of angioedema: Clinical features, diagnosis, and
management", section on 'Clinical features'.)
Upper airway injury – Injury to the airway from smoke or thermal
or chemical burns should be evident from the history. The child
typically does not have fever or a viral prodrome.
Anomalies of the upper airway – Hoarseness and stridor caused
by anomalies of the upper airway (eg, laryngeal webs,
laryngomalacia, vocal cord paralysis, congenital subglottic
stenosis, and subglottic hemangioma) and laryngeal papillomas
have a more chronic course with absence of fever and
symptoms of upper respiratory tract illness, unless the
presentation is due to exacerbation of airway narrowing from
the impact of a concomitant viral infection. (See "Assessment of
stridor in children" and"Hoarseness in children: Etiology and
management" and "Congenital anomalies of the larynx".)
Other potential mimickers of croup – Other potential mimickers
of croup include bronchogenic cyst (which can cause airway
compression) and early Guillain-Barré syndrome (involvement
of the laryngeal nerve may cause vocal cord paralysis) [49,50].
(See "Congenital anomalies of the intrathoracic airways and
tracheoesophageal fistula", section on 'Bronchogenic
cyst' and "Epidemiology, clinical features, and diagnosis of
Guillain-Barré syndrome in children", section on 'Clinical
features' and"Hoarseness in children: Etiology and
management", section on 'Vocal fold paralysis'.)
INFORMATION FOR PATIENTS — UpToDate offers two types
of patient education materials, "The Basics" and "Beyond the
Basics." The Basics patient education pieces are written in plain
language, at the 5th
to 6th
grade reading level, and they answer
the four or five key questions a patient might have about a given
condition. These articles are best for patients who want a
general overview and who prefer short, easy-to-read materials.
Beyond the Basics patient education pieces are longer, more
sophisticated, and more detailed. These articles are written at
the 10th
to 12th
grade reading level and are best for patients who
want in-depth information and are comfortable with some
medical jargon.
Here are the patient education articles that are relevant to this
topic. We encourage you to print or e-mail these topics to your
patients. (You can also locate patient education articles on a
variety of subjects by searching on "patient info" and the
keyword(s) of interest.)
●Basics topic (see "Patient information: Croup (The
Basics)")
●Beyond the Basics topic (see "Patient information:
Croup in infants and children (Beyond the Basics)")
SUMMARY AND RECOMMENDATIONS
●The term croup has been used to describe a variety of
upper respiratory conditions in children, including
laryngitis, laryngotracheitis, laryngotracheobronchitis,
bacterial tracheitis, or spasmodic croup.
(See 'Definitions' above.)
●Croup is usually caused by viruses. Bacterial infection
may occur secondarily. Parainfluenza virus type 1 is the
most common cause of croup; other causes include
respiratory syncytial virus and influenza virus.
(See 'Etiology' above.)
●Croup most commonly occurs in children 6 to 36 months
of age. Most cases occur in the fall or early winter.
(See 'Epidemiology' above.)
●Host factors that may contribute to the development of
croup include functional or anatomic susceptibility to
upper airway narrowing. (See 'Pathogenesis' above.)
●The clinical presentation of croup depends upon the
specific croup syndrome and the degree of upper airway
obstruction. (See 'Clinical presentation' above.)
●The onset of symptoms in laryngotracheitis is gradual,
beginning with nasal irritation, congestion, and coryza.
Fever, hoarseness, barking cough, and stridor usually
develop during the next 12 to 48 hours. Rapid progression
or signs of lower airway involvement suggest a more
serious illness. (See 'Laryngotracheitis' above.)
●The onset of symptoms in spasmodic croup is sudden
and always occurs at night. Fever is typically absent, but
mild upper respiratory tract symptoms may be present.
(See 'Spasmodic croup' above.)
●Bacterial tracheitis (picture 1 and image 4) may present
acutely or as marked worsening during the course of an
antecedent viral upper respiratory infection. Clinical
manifestations of bacterial tracheitis include fever, toxic
appearance, and severe respiratory distress.
(See 'Bacterial tracheitis' above and "Bacterial tracheitis
in children: Clinical features and diagnosis".)
●The objectives of the evaluation of the child with croup
include assessment of severity and exclusion of other
causes of upper airway obstruction.
(See 'Overview'above.)
●Rapid assessment of general appearance, vital signs,
pulse oximetry, airway stability, and mental status are
necessary to identify children with severe respiratory
distress and/or impending respiratory failure. (See 'Rapid
assessment and initial management' above.)
●The history should include a description of the onset,
duration and progression of symptoms, and ascertain
whether there are any underlying conditions that
predispose to a more severe course.
(See 'History' above.)
●Aspects of the examination that are useful in assessing
the severity of upper airway obstruction include overall
appearance (including the presence of stridor at rest or
only with agitation), quality of voice, work of breathing,
tidal volume and air entry, and the presence of wheezing.
(See 'Examination' above.)
●The diagnosis of croup is clinical, based upon the
presence of a barking cough and stridor. Neither
radiographs nor laboratory tests are necessary to make
the diagnosis. However, radiographs may be helpful in
excluding other causes if the diagnosis is in question.
(See 'Diagnosis' above.)
●The differential diagnosis of croup includes other causes
of stridor and/or respiratory distress. The primary
considerations are those with acute onset, particularly
those that may rapidly progress to complete upper airway
obstruction, and those that require specific therapy.
Important considerations include acute epiglottitis,
peritonsillar and retropharyngeal abscesses, foreign body
aspiration, acute angioneurotic edema, upper airway
injury, and congenital anomalies of the upper airway.
(See 'Differential diagnosis' above.)
Use of UpToDate is subject to the Subscription and License Agreement.
REFERENCES
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2. Cherry JD. Croup (laryngitis, laryngotracheitis, spasmodic croup, laryngotracheobronchitis, bacterial tracheitis, and laryngotracheobronchopneumonitis) and epiglottitis (supraglottitis). In: Feigin and Cherry’s Textbook of Pediatric Infectious Diseases, 7th ed, Cherry JD, Harrison GJ, Kaplan SL, et al (Eds), Elsevier Saunders, Philadelphia 2014. p.241.
3. Cooper T, Kuruvilla G, Persad R, El-Hakim H. Atypical croup: association with airway lesions, atopy, and esophagitis. Otolaryngol Head Neck Surg 2012; 147:209.
4. Peltola V, Heikkinen T, Ruuskanen O. Clinical courses of croup caused by influenza and parainfluenza viruses. Pediatr Infect Dis J 2002; 21:76.
5. Counihan ME, Shay DK, Holman RC, et al. Human parainfluenza virus-associated hospitalizations among children less than five years of age in the United States. Pediatr Infect Dis J 2001; 20:646.
6. Rihkanen H, Rönkkö E, Nieminen T, et al. Respiratory viruses in laryngeal croup of young children. J Pediatr 2008; 152:661.
7. Weinberg GA, Hall CB, Iwane MK, et al. Parainfluenza virus infection of young children: estimates of the population-based burden of hospitalization. J Pediatr 2009; 154:694.
8. Kuypers J, Martin ET, Heugel J, et al. Clinical disease in children associated with newly described coronavirus subtypes. Pediatrics 2007; 119:e70.
9. Sung JY, Lee HJ, Eun BW, et al. Role of human coronavirus NL63 in hospitalized children with croup. Pediatr Infect Dis J 2010; 29:822.
10. van der Hoek L, Sure K, Ihorst G, et al. Croup is associated with the novel coronavirus NL63. PLoS Med 2005; 2:e240.
11. Døllner H, Risnes K, Radtke A, Nordbø SA. Outbreak of human metapneumovirus infection in norwegian children. Pediatr Infect Dis J 2004; 23:436.
12. Bjornson CL, Johnson DW. Croup. Lancet 2008; 371:329. 13. Segal AO, Crighton EJ, Moineddin R, et al. Croup
hospitalizations in Ontario: a 14-year time-series analysis. Pediatrics 2005; 116:51.
14. Rosychuk RJ, Klassen TP, Metes D, et al. Croup presentations to emergency departments in Alberta, Canada: a large population-based study. Pediatr Pulmonol 2010; 45:83.
15. Pruikkonen H, Dunder T, Renko M, et al. Risk factors for croup in children with recurrent respiratory infections: a case-control study. Paediatr Perinat Epidemiol 2009; 23:153.
16. Salzman MB, Filler HF, Schechter CB. Passive smoking and croup. Arch Otolaryngol Head Neck Surg 1987; 113:866.
17. Marx A, Török TJ, Holman RC, et al. Pediatric hospitalizations for croup (laryngotracheobronchitis): biennial increases associated with human parainfluenza virus 1 epidemics. J Infect Dis 1997; 176:1423.
18. DAVISON FW. Acute laryngeal obstruction in children. J Am Med Assoc 1959; 171:1301.
19. Davison FW. Acute obstructive laryngitis in children. Penn Med J 1950; 53:250.
20. Szpunar J, Glowacki J, Laskowski A, Miszke A. Fibrinous laryngotracheobronchitis in children. Arch Otolaryngol 1971; 93:173.
21. MORGAN EA, WISHART DE. Laryngotracheo-bronchitis (a statistical review of 549 cases). Can Med Assoc J 1947; 56:8.
22. Orton HB, Smith EL, Bell HO, et al. Acute laryngotracheobronchitis: analysis of sixty-two cases with report of autopsies in eight cases. Arch Otolaryngol 1941; 33:926.
23. Richards L. A further study of the pathology of acute laryngo-tracheobronchitis in children. Ann Otol Rhinol Laryngol 1938; 47:326.
24. Hide DW, Guyer BM. Recurrent croup. Arch Dis Child 1985; 60:585.
25. Van Bever HP, Wieringa MH, Weyler JJ, et al. Croup and recurrent croup: their association with asthma and allergy. An epidemiological study on 5-8-year-old children. Eur J Pediatr 1999; 158:253.
26. Gilger MA. Pediatric otolaryngologic manifestations of gastroesophageal reflux disease. Curr Gastroenterol Rep 2003; 5:247.
27. Welliver RC, Sun M, Rinaldo D. Defective regulation of immune responses in croup due to parainfluenza virus. Pediatr Res 1985; 19:716.
28. Welliver RC, Wong DT, Middleton E Jr, et al. Role of parainfluenza virus-specific IgE in pathogenesis of croup and wheezing subsequent to infection. J Pediatr 1982; 101:889.
29. Thompson M, Vodicka TA, Blair PS, et al. Duration of symptoms of respiratory tract infections in children: systematic review. BMJ 2013; 347:f7027.
30. Cherry JD. The treatment of croup: continued controversy due to failure of recognition of historic, ecologic, etiologic and clinical perspectives. J Pediatr 1979; 94:352.
31. Kaditis AG, Wald ER. Viral croup: current diagnosis and treatment. Pediatr Infect Dis J 1998; 17:827.
32. Mauro RD, Poole SR, Lockhart CH. Differentiation of epiglottitis from laryngotracheitis in the child with stridor. Am J Dis Child 1988; 142:679.
33. Kasian GF, Bingham WT, Steinberg J, et al. Bacterial tracheitis in children. CMAJ 1989; 140:46.
34. Duval M, Tarasidis G, Grimmer JF, et al. Role of operative airway evaluation in children with recurrent croup: a retrospective cohort study. Clin Otolaryngol 2015; 40:227.
35. Delany DR, Johnston DR. Role of direct laryngoscopy and bronchoscopy in recurrent croup. Otolaryngol Head Neck Surg 2015; 152:159.
36. Rankin I, Wang SM, Waters A, et al. The management of recurrent croup in children. J Laryngol Otol 2013; 127:494.
37. Jabbour N, Parker NP, Finkelstein M, et al. Incidence of operative endoscopy findings in recurrent croup. Otolaryngol Head Neck Surg 2011; 144:596.
38. Chun R, Preciado DA, Zalzal GH, Shah RK. Utility of bronchoscopy for recurrent croup. Ann Otol Rhinol Laryngol 2009; 118:495.
39. Alberta Clinical Practice Guidelines Guideline Working Group. Guidelines for the diagnosis and management of croup http://www.topalbertadoctors.org.sci-hub.org/informed_practice/cpgs/croup.html (Accessed on February 22, 2011).
40. Fleisher G. Infectious disease emergencies. In: Textbook of Pediatric Emergency Medicine, 5th ed, Fleisher GR, Ludwig S, Henretig FM (Eds), Lippincott, Williams & Wilkins, Philadelphia 2006. p.783.
41. Tibballs J, Watson T. Symptoms and signs differentiating croup and epiglottitis. J Paediatr Child Health 2011; 47:77.
42. Diaz JH, Lockhart CH. Early diagnosis and airway management of acute epiglottitis in children. South Med J 1982; 75:399.
43. Westley CR, Cotton EK, Brooks JG. Nebulized racemic epinephrine by IPPB for the treatment of croup: a double-blind study. Am J Dis Child 1978; 132:484.
44. Mills JL, Spackman TJ, Borns P, et al. The usefulness of lateral neck roentgenograms in laryngotracheobronchitis. Am J Dis Child 1979; 133:1140.
45. Bernstein T, Brilli R, Jacobs B. Is bacterial tracheitis changing? A 14-month experience in a pediatric intensive care unit. Clin Infect Dis 1998; 27:458.
46. Cherry JD. Newer respiratory viruses: their role in respiratory illnesses of children. In: Advances in Pediatrics, Vol 20, Schulman I (Ed), Mosby Year Book, Chicago 1973. p.225.
47. Denny FW, Clyde WA Jr. Acute lower respiratory tract infections in nonhospitalized children. J Pediatr 1986; 108:635.
48. Henrickson KJ, Hoover S, Kehl KS, Hua W. National disease burden of respiratory viruses detected in children by polymerase chain reaction. Pediatr Infect Dis J 2004; 23:S11.
49. Lin CY, Chi H, Shih SL, et al. A 4-year-old boy presenting with recurrent croup. Eur J Pediatr 2010; 169:249.
50. Hsia SH, Lin JJ, Wu CT, et al. Guillain-Barré syndrome presenting as mimicking croup. Am J Emerg Med 2010; 28:749.e1.
Topic 6002 Version 20.0
Croup: Approach to management Author Charles R Woods, MD, MS Section Editors Sheldon L Kaplan, MD Anna H Messner, MD Deputy Editor Carrie Armsby, MD, MPH Disclosures: Charles R Woods, MD, MS Other Financial Interest: Cerexa [Epiglottitis (Data Safety Monitoring Board for pediatric trials of the antibiotic agent ceftaroline)]. Sheldon L Kaplan, MDGrant/Research/Clinical Trial Support: Pfizer [vaccine (PCV13)]; Forest Lab [antibiotic (Ceftaroline)]; Optimer [antibiotic (fidaxomicin)]. Consultant/Advisory Boards: Pfizer [vaccine (PCV13)]. Anna H Messner, MD Nothing to disclose. Carrie Armsby, MD, MPH Nothing to disclose.
Contributor disclosures are reviewed for conflicts of interest by the editorial group. When found, these are addressed by vetting through a multi-level review process, and through requirements for references to be provided to support the content. Appropriately referenced content is required of all authors and must conform to UpToDate standards of evidence.
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All topics are updated as new evidence becomes available and our peer review process is complete. Literature review current through: Jul 2015. | This topic last updated: Apr 17, 2015.
INTRODUCTION — Croup (laryngotracheitis) is a
respiratory illness characterized by inspiratory stridor,
barking cough, and hoarseness. It typically occurs in
children six months to three years of age and is chiefly
caused by parainfluenza virus. (See "Croup: Clinical
features, evaluation, and diagnosis".)
Most children with croup who seek medical attention
have a mild, self-limited illness and can be successfully
managed as outpatients. The clinician must be able to
identify children with mild symptoms, who can be safely
managed at home, and those with moderate to severe
croup or rapidly progressing symptoms, who require full
evaluation and possible treatment in the office or
emergency department setting. (See 'Severity
assessment' below and 'Outpatient treatment' below.)
There is no definitive treatment for the viruses that cause
croup. Pharmacologic therapy is directed toward
decreasing airway edema, and supportive care is
directed toward the provision of respiratory support and
the maintenance of hydration. Corticosteroids and
nebulized epinephrine are the cornerstones of therapy;
their use is supported by substantial clinical evidence.
(See 'Initial treatment' below and "Croup: Pharmacologic
and supportive interventions".)
The approach to the management of croup will be
discussed below. The clinical features and evaluation of
croup, and the evidence supporting the use of the
pharmacologic and supportive interventions included
below are discussed separately. (See "Croup: Clinical
features, evaluation, and diagnosis" and "Croup:
Pharmacologic and supportive interventions".)
SEVERITY ASSESSMENT — This initial step in the
management of a child with croup is assessing severity
of illness. The first contact with the healthcare system
may occur by phone and the healthcare provider must be
able to distinguish children with more severe symptoms
who need immediate medical attention from those who
can be managed at home. (See 'Telephone
triage' below.)
When the child is seen in the office or emergency
department, croup severity is assessed by examining the
child and using a clinical scoring system. (See 'Croup
severity score' below.)
Telephone triage — When assessing patients by phone,
the healthcare provider must distinguish children who
need immediate medical attention or further evaluation
from those who can be managed at home. Children who
need further evaluation include those who have:
●Stridor at rest
●Rapid progression of symptoms (ie, symptoms of
upper airway obstruction after less than 12 hours of
illness)
●Inability to tolerate oral fluids
●Underlying known airway abnormality (eg,
subglottic stenosis, subglottic hemangioma,
previous intubation)
●Previous episodes of moderate to severe croup
●Medical conditions that predispose to respiratory
failure (eg, neuromuscular disorders or
bronchopulmonary dysplasia)
●Parental concern that cannot be relieved by
reassurance
●Prolonged symptoms (more than three to seven
days) or an atypical course (perhaps indicating an
alternative diagnosis) (see "Croup: Clinical features,
evaluation, and diagnosis", section on 'Differential
diagnosis')
Patients who are assessed by phone and determined to
have mild symptoms and none of the above indications
for further evaluation can be managed at home.
(See'Home treatment' below.)
Croup severity score — There are a number of
validated croup scoring systems. The Westley croup
score has been the most extensively studied (table 1) [1].
Severity is determined by the presence or absence of
stridor at rest, the degree of chest wall retractions, air
entry, the presence or absence of pallor or cyanosis, and
the mental status:
●Mild croup (Westley croup score of ≤2) − Children
with mild croup have no stridor at rest (although
stridor may be present when upset or crying), a
barking cough, hoarse cry, and either no, or only
mild, chest wall/subcostal retractions [2-4].
(See 'Mild croup' below.)
●Moderate croup (Westley croup score of 3 to 7) −
Children with moderate croup have stridor at rest,
have at least mild retractions, and may have other
symptoms or signs of respiratory distress, but little
or no agitation [2-4]. (See 'Moderate to severe
croup' below.)
●Severe croup (Westley croup score of ≥8) −
Children with severe croup have significant stridor
at rest, although the loudness of the stridor may
decrease with worsening upper airway obstruction
and decreased air entry [2-4]. Retractions are
severe (including indrawing of the sternum) and the
child may appear anxious, agitated, or pale and
fatigued. Prompt recognition and treatment of
children with severe croup are paramount.
(See 'Moderate to severe croup' below.)
●Impending respiratory failure (Westley croup
score of ≥12) − Croup occasionally results in
significant upper airway obstruction with impending
respiratory failure, heralded by the following signs
[2,4,5]:
•Fatigue and listlessness
•Marked retractions (although retractions may
decrease with increased obstruction and
decreased air entry)
•Decreased or absent breath sounds
•Depressed level of consciousness
•Tachycardia out of proportion to fever
•Cyanosis or pallor
Patients who present to an office clinic with severe
croup or signs and symptoms of impending
respiratory failure should be transported via
emergency medical services to an emergency
department for management. (See 'Moderate to
severe croup' below.)
MILD CROUP — Children with mild symptoms (Westley
croup score of ≤2 (table 1)) should be treated
symptomatically with humidity, fever reduction, and oral
fluids. Many such children can be managed by phone,
provided that none of the criteria for further evaluation
described above are present. (See 'Telephone
triage' above.)
Home treatment — The caregivers of children with mild
croup who are managed at home should be instructed in
provision of supportive care including mist, antipyretics,
and encouragement of fluid intake.
In acute situations and for short periods of time,
caregivers may try sitting with the child in a bathroom
filled with steam generated by running hot water from the
shower to improve symptoms. This may help reassure
parents that "something" is being done to reverse the
symptoms, and anecdotal evidence supports some
benefit with this measure.
Exposure to cold night air also may lessen symptoms of
mild croup, although this has never been systematically
studied. If parents or caregivers wish to use humidifiers
at home, only those that produce mist at room
temperature should be used to avoid the risk of burns
from steam or the heating element.
Instructions should be provided to the caregivers
regarding when to seek medical attention, including
watching for [2]:
●Stridor at rest
●Difficulty breathing
●Pallor or cyanosis
●Severe coughing spells
●Drooling or difficulty swallowing
●Fatigue
●Worsening course
●Fever (>38.5ºC)
●Prolonged symptoms (longer than seven days)
●Suprasternal retractions
Caregivers also should be provided with some guidance
regarding when it is safe for them to drive the child to the
emergency department; emergency medical services
should provide transportation for children who are
severely agitated, pale or cyanotic, struggling to breathe,
or lethargic [2].
Patients who are managed at home should receive a
follow-up phone call within 24 hours.
Outpatient treatment — We suggest that children with
mild croup who are seen in the outpatient setting be
treated with a single dose of
oral dexamethasone (0.6 mg/kg)(algorithm 1).
Randomized controlled trials in children with mild croup
have demonstrated that treatment with a single dose of
oral dexamethasone (0.15 to 0.6 mg/kg,maximum dose
10 mg) reduces the need for reevaluation, shortens the
duration of symptoms, improves the child's sleep, and
reduces parental stress [6,7]. (See "Croup:
Pharmacologic and supportive interventions", section on
'Dexamethasone'.)
An alternative approach is nonpharmacologic
management with anticipatory guidance about potential
worsening and instructions on when to seek care or
return for follow-up.
Treatment with nebulized epinephrine is not typically
necessary for management of mild croup.
Children with mild croup who are tolerating fluids and
have not received nebulized epinephrine can be sent
home after specific follow-up (which may occur by phone)
has been arranged and the caregiver has received
instructions regarding home care and indications to seek
medical attention as described above. (See 'Home
treatment'above.)
MODERATE TO SEVERE CROUP
Setting and pace of treatment — The appropriate
treatment setting depends upon the severity of
symptoms:
●Children with moderate croup (Westley croup
score 3 to 7; stridor at rest and mild to moderate
retractions, but no or little distress or agitation (table
1)) should be evaluated in the emergency
department or office (provided the office is equipped
to handle acute upper airway obstruction).
●Children with severe croup (Westley croup score
≥8; stridor at rest and marked retractions with
agitation, lethargy, or cyanosis (table 1)) should be
evaluated in the emergency department as they
require aggressive therapy, monitoring, and
supportive care.
The child with severe croup must be approached
cautiously, as any increase in anxiety may worsen airway
obstruction. The parent or caregiver should be instructed
to hold and comfort the child.
Nebulized epinephrine should be added as quickly as
possible, as described below. In the meantime,
healthcare providers should continuously observe the
child and be prepared to provide bag-mask ventilation
and advanced airway techniques if the condition worsens
(algorithm 1). (See 'Initial treatment' below
and 'Respiratory care' below.)
Initial treatment — Initial treatment of moderate to
severe croup includes administration
of dexamethasone and nebulized epinephrine. Children
with moderate to severe croup should also receive
supportive care including humidified air or oxygen,
antipyretics, and encouragement of fluid intake.
(See 'Supportive care' below.)
We recommend administration
of dexamethasone (0.6 mg/kg, maximum of 10 mg) in all
children with moderate to severe croup. Dexamethasone
should be administered by the least invasive route
possible: oral if oral intake is tolerated, intravenous (IV) if
IV access has been established, or intramuscular (IM) if
oral intake is not tolerated and IV access has not been
established. The oral preparation of dexamethasone
(1 mg/mL) has an unpleasant taste. The IV preparation is
more concentrated (4 mg per mL) and can be given orally
mixed with syrup [2,8-10]. A single dose of
nebulized budesonide (2 mg [2 mL solution] via
nebulizer) is an alternative option, particularly for children
who are vomiting [2,4,11].
The benefit of corticosteroids for moderate to severe
croup have been demonstrated in a meta-analysis of 24
trials that found improvement in croup scores six hours
after treatment, fewer return visits or readmissions,
decreased length of stay in the emergency department or
hospital, and decreased epinephrine use [12].
(See "Croup: Pharmacologic and supportive
interventions", section on 'Glucocorticoids'.)
In addition to dexamethasone, we recommend
nebulized epinephrine in all patients with moderate to
severe croup:
●Racemic epinephrine is administered as
0.05 mL/kg per dose (maximum of 0.5 mL) of a 2.25
percent solution diluted to 3 mL total volume with
normal saline. It is given via nebulizer over 15
minutes.
●L-epinephrine is administered as 0.5 mL/kg per
dose (maximum of 5 mL) of a 1:1000 dilution. It is
given via nebulizer over 15 minutes.
The benefits of nebulized epinephrine have been
demonstrated in a meta-analysis of eight trials that found
improvement in croup score 30 minutes post-treatment
and shorter hospital stay; there was no difference in
effectiveness between racemic epinephrine and L-
epinephrine [13]. (See "Croup: Pharmacologic and
supportive interventions", section on 'Nebulized
epinephrine'.)
Observation and disposition — Patients should be
observed for three to four hours after initial treatment.
The need for additional intervention and/or admission to
the hospital is determined chiefly by the response to
therapy with corticosteroids and nebulized epinephrine.
The majority of children with moderate croup have
symptomatic improvement after treatment with nebulized
epinephrine and corticosteroids and can be discharged
home, whereas those with severe symptoms on
presentation are more likely to require hospitalization.
Discharge to home — Patients who have a good
response to initial treatment should be observed for three
to four hours after pharmacologic intervention (algorithm
1) [14-17]. Croup symptoms usually improve within 30
minutes of administration of nebulized epinephrine, but
may recur as the effects of epinephrine wear off (usually
by two hours) [18,19]. Children who have recurrence or
worsening of moderate to severe symptoms during the
observation period should receive additional racemic
epinephrine and should be admitted to the hospital.
(See 'Indications for hospital admission' below.)
After three to four hours of observation, children who
remain comfortable may be discharged home if they
meet the following criteria [14-17]:
●No stridor at rest
●Normal pulse oximetry
●Good air exchange
●Normal color
●Normal level of consciousness
●Demonstrated ability to tolerate fluids by mouth
●Caregivers understand the indications for return to
care and would be able to return if necessary
Before discharge, follow-up with the primary care
provider should be arranged within the next 24 hours.
Instructions regarding home treatment should be
provided. (See'Home treatment' above.)
Approximately 5 percent of children well enough for
discharge from the emergency department after receiving
corticosteroids and nebulized epinephrine treatments are
expected to return for care [20]. Relapse within 24 hours
is unlikely in those who have minimal symptoms at the
time of discharge [21].
Indications for hospital admission — Patients with
ongoing severe symptoms after initial treatment should
receive additional nebulized epinephrine and should be
admitted to the hospital. Nebulized epinephrine can be
repeated every 15 to 20 minutes. The administration of
three or more doses within a two- to three-hour time
period should prompt initiation of close cardiac
monitoring if this is not already underway.
Children with persistent moderate symptoms can be
observed for at least four hours before deciding whether
they require hospital admission as the effect
ofdexamethasone may not be apparent for several hours
[2].
Indications for inpatient admission include [2,22]:
●Severe croup with poor air entry, altered
consciousness, or impending respiratory failure
●Moderate/severe croup with persistent or
deteriorating respiratory distress after treatment
with nebulized epinephrine and corticosteroids
●"Toxic" appearance or clinical picture suggesting
serious secondary bacterial infection
●Need for supplemental oxygen
●Severe dehydration
Additional factors that influence the decision regarding
admission include [2,22]:
●Young age, particularly younger than six months
●Recurrent visits to the emergency department
within 24 hours
●Ability of the family to comprehend the instructions
regarding recognition of features that indicate the
need to return for care
●Ability of the family to return for care (eg, distance
from home to care site, weather/travel conditions)
Admission to the pediatric intensive care unit (PICU) is
warranted if any of the following are present:
●Respiratory failure requiring endotracheal
intubation
●Persistent severe symptoms requiring frequent
nebulized epinephrine dosing
●Underlying conditions placing the child at high risk
for progressive respiratory failure (eg,
neuromuscular disease or bronchopulmonary
dysplasia)
Approximately 8 to 15 percent of children with croup
presenting to the emergency department require
hospitalization; only 1 percent require admission to the
PICU [20,23].
Inpatient management — Children admitted to the
hospital for management of croup should receive close
respiratory monitoring and supportive care.
Supportive care — Supportive care for children
hospitalized with moderate to severe croup includes:
●Fluids − Administration of intravenous fluids may
be necessary in some children. Fever and
tachypnea may increase fluid requirements, and
respiratory difficulty may prevent the child from
achieving adequate oral intake. (See "Maintenance
fluid therapy in children".)
●Fever control − High fever can contribute to
tachypnea and respiratory distress in children with
croup, and treatment with antipyretics can improve
work of breathing and insensible fluid losses.
●Comfort − Care must be taken to avoid provoking
agitation or anxiety in children with moderate to
severe croup as this can worsen the degree of
respiratory distress and airway obstruction. Children
with severe croup should be approached cautiously
and unnecessary invasive interventions should be
avoided. The parent or caregiver should be
instructed to hold and comfort the child and to assist
in care. The use of sedatives or anxiolytics to
reduce agitation is discouraged as this may cause
respiratory depression.
Respiratory care — Respiratory support for children
hospitalized with croup may include the following:
●Nebulized epinephrine − Repeated doses of
nebulized epinephrine may be warranted for
children with moderate to severe distress. It is not
always required; one study of 365 hospitalizations
for croup found that only 49 percent required
additional nebulized epinephrine during the
inpatient stay [24]. Nebulized epinephrine can be
repeated every 15 to 20 minutes. However, children
who require frequent doses of epinephrine (eg,
more frequently than every one to two hours)
should beadmitted/transferred to an intensive care
unit for close cardiopulmonary monitoring.
(See "Croup: Pharmacologic and supportive
interventions", section on 'Nebulized epinephrine'.)
●Supplemental oxygen − Oxygen should be
administered to children who are hypoxemic
(oxygen saturation of <92 percent in room air).
Supplemental oxygen should be humidified to
decrease drying effects on the airways, since drying
may impede the physiologic removal of airway
secretions via mucociliary and cough mechanisms.
(See "Continuous oxygen delivery systems for
infants, children, and adults".)
●Mist − Humidified air is frequently used in the
treatment of croup, although a meta-analysis of
three trials evaluating the use of humidified air in
croup found only marginal improvement in croup
scores [25]. Mist therapy may provide a sense of
comfort and reassurance to both the child and
family; however, if the child is instead agitated by
the mist, it should be discontinued. (See "Croup:
Pharmacologic and supportive interventions",
section on 'Mist therapy'.)
●Heliox − Heliox is a mixture of helium (70 to 80
percent) and oxygen (20 to 30 percent). Heliox may
decrease the work of breathing in children with
croup by reducing turbulent airflow. A meta-analysis
of three trials concluded that while there is evidence
to suggest a short-term benefit of heliox, a larger
trial is needed before recommendations regarding
the use of heliox in children with croup can be made
[26]. While the evidence from these trials does not
suggest a large benefit from Heliox to support its
routine use in the management of croup, in patients
with severe symptoms who are at risk for
respiratory failure, it may be used in an attempt to
avoid the need for intubation. An important limitation
of heliox use is the low fractional concentration of
inspired oxygen (FiO2) in the gas mixture, which
may not be adequate for children with hypoxia.
(See "Croup: Pharmacologic and supportive
interventions", section on 'Heliox'.)
●Intubation − The need for intubation should be
anticipated in children with progressive respiratory
failure so that the procedure can be performed in a
controlled setting if possible. Intubation can be
challenging due to the narrowed subglottic airway
and should be performed with the assistance of a
skilled provider (ie, an anesthesiologist or
otolaryngologist). Neuromuscular blocking agents
should be avoided unless the ability to provide bag-
mask ventilation has been demonstrated. An
endotracheal tube that is 0.5 to 1 mm smaller than
would typically be used should be placed.
(See 'Croup severity score' above and "Emergency
endotracheal intubation in children", section on
'Endotracheal tube'.)
Endotracheal intubation is rarely required for
management of croup. In a large study at one
institution, less than 1 percent of children admitted
to the hospital for croup required intubation [23].
Repeated corticosteroid dosing — Repeat doses of
corticosteroids are not necessary on a routine basis and
may have adverse effects. Moderate to severe symptoms
that persist for more than a few days should prompt
investigation for other causes of airway obstruction.
(See "Croup: Pharmacologic and supportive
interventions", section on 'Repeated dosing' and "Croup:
Clinical features, evaluation, and diagnosis", section on
'Differential diagnosis' and "Assessment of stridor in
children".)
Monitoring — Monitoring should include close
observation of mental status and respiratory status,
including monitoring for stridor, cyanosis, air entry, and
retractions. Pulse oximetry monitoring is useful to detect
hypoxia; however, it is not a sensitive tool for assessing
the severity of croup [22].
Infection control — Children who are admitted to the
hospital with croup should be managed with contact
precautions (ie, gown and gloves for contact), particularly
if parainfluenza or respiratory syncytial virus is the
suspected etiology. If influenza is suspected, droplet
isolation measures (ie, respiratory mask within three feet)
also should be followed. (See "General principles of
infection control".)
Discharge criteria — Children who require hospital
admission may be discharged when they meet the
following criteria:
●No stridor at rest
●Normal pulse oximetry in room air
●Good air exchange
●Normal color
●Normal level of consciousness
●Demonstrated ability to tolerate fluids by mouth
Atypical course — Children admitted for croup typically
remain in the hospital for less than 36 hours [24]. The
child who does not show improvement as expected (over
the course of one to two days) may have an underlying
airway abnormality or may be developing a complication
of croup. Further evaluation with radiographs of the soft
tissues of the neck, or consultation with otolaryngology,
may be warranted. A biphasic illness with poor response
to nebulized epinephrine in conjunction with high fever
and toxic appearance should prompt consideration of
bacterial tracheitis (picture 1) [2]. (See "Croup: Clinical
features, evaluation, and diagnosis", section on
'Differential diagnosis' and "Bacterial tracheitis in
children: Clinical features and diagnosis".)
FOLLOW-UP — Any patient who was admitted to the
hospital, received nebulized epinephrine, or had a
prolonged outpatient visit should have follow-up
scheduled with the primary care provider within 24 hours
or as soon as can be arranged. Although some children
may continue to have mild to moderate symptoms at the
time of follow-up, there are no studies that support the
routine use of corticosteroid therapy beyond 24 hours.
Follow-up should continue until the child's symptoms
have begun to resolve. The child whose symptoms do
not resolve over the course of approximately seven days
may have an underlying airway abnormality or may be
developing a complication of croup. (See 'Atypical
course' above.)
PROGNOSIS — Symptoms of croup resolve in most
children within three days, but may persist for up to one
week [27,28]. Approximately 8 to 15 percent of children
with croup require hospital admission [20,29], and among
those, less than 1 percent require intubation [23].
Mortality is rare, occurring in <0.5 percent of intubated
children [30].
Complications — Complications of croup are
uncommon. Children with moderate to severe croup are
at risk for hypoxemia (oxygen saturation <92 percent in
room air) and respiratory failure. Other complications
include pulmonary edema, pneumothorax, and
pneumomediastinum [31]. These complications can be
anticipated and managed by aggressive monitoring and
intervention in the medical setting. Out-of-hospital cardiac
arrest and death also have been reported [32].
Secondary bacterial infections may arise from croup.
Bacterial tracheitis, bronchopneumonia, and pneumonia
occur in a small number of patients [5,28,33,34]. In most
instances, the child has been relatively stable or
beginning to improve after several days of illness, but
then suddenly worsens, with higher or recurrent fever,
increased (and potentially productive)
cough, and/or respiratory distress. (See "Bacterial
tracheitis in children: Clinical features and diagnosis",
section on 'Clinical features' and"Community-acquired
pneumonia in children: Clinical features and diagnosis",
section on 'Clinical presentation'.)
Recurrent symptoms — Approximately 5 percent of
children treated for croup in the outpatient setting have
repeat visits for recurrent symptoms within seven days
following discharge [20]. Children who have recurrent
episodes of classic viral croup may require radiographic
evaluation or bronchoscopy to evaluate for underlying
airway abnormalities. Recurrent episodes of croup-like
symptoms occurring outside the typical age range for
"viral croup" (ie, six months to three years) and recurrent
episodes that do not appear to be simple "spasmodic
croup" should raise suspicion for large airway lesions,
gastroesophageal reflux or eosinophilic esophagitis, or
atopic conditions [35-40]. (See "Assessment of stridor in
children" and "Croup: Clinical features, evaluation, and
diagnosis", section on 'Spasmodic croup'.)
INFORMATION FOR PATIENTS — UpToDate offers two
types of patient education materials, "The Basics" and
"Beyond the Basics." The Basics patient education
pieces are written in plain language, at the 5th to 6
th grade
reading level, and they answer the four or five key
questions a patient might have about a given condition.
These articles are best for patients who want a general
overview and who prefer short, easy-to-read materials.
Beyond the Basics patient education pieces are longer,
more sophisticated, and more detailed. These articles are
written at the 10th to 12
th grade reading level and are best
for patients who want in-depth information and are
comfortable with some medical jargon.
Here are the patient education articles that are relevant
to this topic. We encourage you to print or e-mail these
topics to your patients. (You can also locate patient
education articles on a variety of subjects by searching
on "patient info" and the keyword(s) of interest.)
●Basics topics (see "Patient information: Croup
(The Basics)")
●Beyond the Basics topics (see "Patient
information: Croup in infants and children (Beyond
the Basics)")
SUMMARY AND RECOMMENDATIONS
●Children with croup should be seen in the office or
emergency department if they have stridor at rest,
an underlying airway abnormality, previous
episodes of moderate to severe croup, underlying
conditions that may predispose to respiratory
failure, rapid progression of symptoms, inability to
tolerate fluids, prolonged symptoms, or an atypical
course. (See 'Telephone triage' above.)
●Children with mild symptoms (ie, no stridor at rest
and no respiratory distress) can be managed at
home. Families should be instructed in provision of
supportive care and indications to seek medical
attention. (See 'Home treatment' above.)
●We suggest that a single dose of
oral dexamethasone (0.6 mg/kg) be used when
electing to treat children with mild croup who are
seen in the outpatient setting (algorithm 1) (Grade
2A). (See 'Outpatient treatment' above and "Croup:
Pharmacologic and supportive interventions",
section on 'Dexamethasone'.)
●Children with moderate croup (ie, stridor at rest
with mild to moderate retractions) should be
evaluated in the office or emergency department,
and those with severe croup (stridor at rest with
marked retractions and significant distress or
agitation) should be evaluated in the emergency
department (table 1). Children with severe croup
must be approached cautiously, as any increase in
anxiety may worsen airway obstruction.
(See 'Moderate to severe croup' above.)
●We recommend that children with moderate to
severe croup be treated with a single dose
of dexamethasone (0.6 mg/kg, maximum of 10 mg)
by the least invasive route (algorithm 1) (Grade
1A). (See 'Initial treatment' above and "Croup:
Pharmacologic and supportive interventions",
section on 'Glucocorticoids'.)
●We recommend that children with moderate to
severe croup be treated with
nebulized epinephrine (Grade 1A) in addition
to dexamethasone (algorithm 1). (See'Initial
treatment' above and "Croup: Pharmacologic and
supportive interventions", section on 'Nebulized
epinephrine'.)
•Racemic epinephrine is administered as
0.05 mL/kg per dose (maximum of 0.5 mL) of
a 2.25 percent solution diluted to 3 mL total
volume with normal saline. It is given via
nebulizer over 15 minutes.
•L-epinephrine is administered as
0.5 mL/kg per dose (maximum of 5 mL) of a
1:1000 dilution. It is given via nebulizer over
15 minutes.
Nebulized epinephrine can be repeated every 15 to
20 minutes. The administration of three or more
doses within a two- to three-hour time period should
prompt initiation of close cardiac monitoring if this is
not already underway.
●Children with moderate to severe croup should be
observed for three to four hours after intervention.
Those who improve may be discharged home.
Children with persistent or worsening symptoms
during the observation period should be admitted to
the hospital. (See 'Discharge to home' above
and 'Indications for hospital admission' above.)
●Management of children hospitalized for croup
includes:
•Supportive care with provision of intravenous
fluids and fever reduction. (See 'Supportive
care' above.)
•Respiratory care with repeated doses of
nebulized epinephrine, as indicated by
respiratory distress, and administration of
humidified air or oxygen, as indicated by
hypoxemia. (See 'Respiratory care' above.)
•Monitoring for worsening respiratory distress.
(See 'Monitoring' above.)
We suggest not using repeated doses of
corticosteroids (Grade 2C). (See 'Repeated
corticosteroid dosing' above and "Croup:
Pharmacologic and supportive interventions",
section on 'Repeated dosing'.)
●Children who have moderate to severe symptoms
that persist for more than a few days, or recurring
episodes of croup not associated with other
manifestations of a viral illness (no
fever and/or rhinorrhea) should undergo
investigation for other causes of upper airway
obstruction. (See 'Atypical course' above
and 'Recurrent symptoms' above and "Croup:
Clinical features, evaluation, and diagnosis", section
on 'Differential diagnosis'.)
●Children who received nebulized epinephrine, had
a prolonged outpatient visit, or were admitted to the
hospital should have follow-up scheduled with the
primary care provider within 24 hours of discharge
or as soon as follow-up can be arranged. Most
children with croup recover uneventfully.
(See 'Follow-up' above and 'Prognosis'above.)
Use of UpToDate is subject to the Subscription and License Agreement.
REFERENCES
1. Westley CR, Cotton EK, Brooks JG. Nebulized racemic epinephrine by IPPB for the treatment of croup: a double-blind study. Am J Dis Child 1978; 132:484.
2. Alberta Clinical Practice Guidelines Guideline Working Group. Guidelines for the diagnosis and management of croup. www.topalbertadoctors.org/download/252/croup_guideline.pdf (Accessed on March 13, 2015).
3. Cherry JD. Clinical practice. Croup. N Engl J Med 2008; 358:384.
4. Clarke M, Allaire J. An evidence-based approach to the evaluation and treatment of croup in children. Pediatric Emergency Medicine Practice 2012; 9:1.
5. Fleisher G. Infectious disease emergencies. In: Textbook of Pediatric Emergency Medicine, 5th ed, Fleisher GR, Ludwig S, Henretig FM (Eds), Lippincott, Williams & Wilkins, Philadelphia 2006. p.783.
6. Geelhoed GC, Turner J, Macdonald WB. Efficacy of a small single dose of oral dexamethasone for outpatient croup: a double blind placebo controlled clinical trial. BMJ 1996; 313:140.
7. Bjornson CL, Klassen TP, Williamson J, et al. A randomized trial of a single dose of oral dexamethasone for mild croup. N Engl J Med 2004; 351:1306.
8. Klassen TP, Craig WR, Moher D, et al. Nebulized budesonide and oral dexamethasone for treatment of croup: a randomized controlled trial. JAMA 1998; 279:1629.
9. Paul RI. Oral dexamethasone for croup (commentary). AAP Grand Rounds 2004; 12:67.
10. Duggan DE, Yeh KC, Matalia N, et al. Bioavailability of oral dexamethasone. Clin Pharmacol Ther 1975; 18:205.
11. Johnson DW, Jacobson S, Edney PC, et al. A comparison of nebulized budesonide, intramuscular dexamethasone, and placebo for moderately severe croup. N Engl J Med 1998; 339:498.
12. Russell KF, Liang Y, O'Gorman K, et al. Glucocorticoids for croup. Cochrane Database Syst Rev 2011; :CD001955.
13. Bjornson C, Russell K, Vandermeer B, et al. Nebulized epinephrine for croup in children. Cochrane Database Syst Rev 2013; 10:CD006619.
14. Prendergast M, Jones JS, Hartman D. Racemic epinephrine in the treatment of laryngotracheitis: can we identify children for outpatient therapy? Am J Emerg Med 1994; 12:613.
15. Ledwith CA, Shea LM, Mauro RD. Safety and efficacy of nebulized racemic epinephrine in conjunction with oral
dexamethasone and mist in the outpatient treatment of croup. Ann Emerg Med 1995; 25:331.
16. Kunkel NC, Baker MD. Use of racemic epinephrine, dexamethasone, and mist in the outpatient management of croup. Pediatr Emerg Care 1996; 12:156.
17. Rizos JD, DiGravio BE, Sehl MJ, Tallon JM. The disposition of children with croup treated with racemic epinephrine and dexamethasone in the emergency department. J Emerg Med 1998; 16:535.
18. Waisman Y, Klein BL, Boenning DA, et al. Prospective randomized double-blind study comparing L-epinephrine and racemic epinephrine aerosols in the treatment of laryngotracheitis (croup). Pediatrics 1992; 89:302.
19. Fitzgerald D, Mellis C, Johnson M, et al. Nebulized budesonide is as effective as nebulized adrenaline in moderately severe croup. Pediatrics 1996; 97:722.
20. Rosychuk RJ, Klassen TP, Metes D, et al. Croup presentations to emergency departments in Alberta, Canada: a large population-based study. Pediatr Pulmonol 2010; 45:83.
21. Brown JC. The management of croup. Br Med Bull 2002; 61:189.
22. Petrocheilou A, Tanou K, Kalampouka E, et al. Viral croup: diagnosis and a treatment algorithm. Pediatr Pulmonol 2014; 49:421.
23. Dobrovoljac M, Geelhoed GC. 27 years of croup: an update highlighting the effectiveness of 0.15 mg/kg of dexamethasone. Emerg Med Australas 2009; 21:309.
24. Narayanan S, Funkhouser E. Inpatient hospitalizations for croup. Hosp Pediatr 2014; 4:88.
25. Moore M, Little P. Humidified air inhalation for treating croup. Cochrane Database Syst Rev 2006; :CD002870.
26. Moraa I, Sturman N, McGuire T, van Driel ML. Heliox for croup in children. Cochrane Database Syst Rev 2013; 12:CD006822.
27. Thompson M, Vodicka TA, Blair PS, et al. Duration of symptoms of respiratory tract infections in children: systematic review. BMJ 2013; 347:f7027.
28. Cherry JD. Croup (laryngitis, laryngotracheitis, spasmodic croup, laryngotracheobronchitis, bacterial tracheitis, and laryngotracheobronchopneumonitis) and epiglottitis
(supraglottitis). In: Feigin and Cherry’s Textbook of Pediatric Infectious Diseases, 7th ed, Cherry JD, Harrison GJ, Kaplan SL, et al (Eds), Elsevier Saunders, Philadelphia 2014. p.241.
29. Johnson D. Croup. Clin Evid 2005; :310. 30. McEniery J, Gillis J, Kilham H, Benjamin B. Review of
intubation in severe laryngotracheobronchitis. Pediatrics 1991; 87:847.
31. Travis KW, Todres ID, Shannon DC. Pulmonary edema associated with croup and epiglottitis. Pediatrics 1977; 59:695.
32. Fisher JD. Out-of-hospital cardiopulmonary arrest in children with croup. Pediatr Emerg Care 2004; 20:35.
33. Sofer S, Dagan R, Tal A. The need for intubation in serious upper respiratory tract infection in pediatric patients (a retrospective study). Infection 1991; 19:131.
34. Rosekrans JA. Viral croup: current diagnosis and treatment. Mayo Clin Proc 1998; 73:1102.
35. Cooper T, Kuruvilla G, Persad R, El-Hakim H. Atypical croup: association with airway lesions, atopy, and esophagitis. Otolaryngol Head Neck Surg 2012; 147:209.
36. Duval M, Tarasidis G, Grimmer JF, et al. Role of operative airway evaluation in children with recurrent croup: a retrospective cohort study. Clin Otolaryngol 2015; 40:227.
37. Delany DR, Johnston DR. Role of direct laryngoscopy and bronchoscopy in recurrent croup. Otolaryngol Head Neck Surg 2015; 152:159.
38. Rankin I, Wang SM, Waters A, et al. The management of recurrent croup in children. J Laryngol Otol 2013; 127:494.
39. Jabbour N, Parker NP, Finkelstein M, et al. Incidence of operative endoscopy findings in recurrent croup. Otolaryngol Head Neck Surg 2011; 144:596.
40. Chun R, Preciado DA, Zalzal GH, Shah RK. Utility of bronchoscopy for recurrent croup. Ann Otol Rhinol Laryngol 2009; 118:495.
Topic 6004 Version 11.0
Croup: Pharmacologic and supportive interventions Author Charles R Woods, MD, MS Section Editor Sheldon L Kaplan, MD Deputy Editor Carrie Armsby, MD, MPH Disclosures: Charles R Woods, MD, MS Other Financial Interest: Cerexa [Epiglottitis (Data Safety Monitoring Board for pediatric trials of the antibiotic agent ceftaroline)]. Sheldon L Kaplan, MDGrant/Research/Clinical Trial Support: Pfizer [vaccine (PCV13)]; Forest Lab [antibiotic (Ceftaroline)]; Optimer [antibiotic (fidaxomicin)]. Consultant/Advisory Boards: Pfizer [vaccine (PCV13)]. Carrie Armsby, MD, MPH Nothing to disclose.
Contributor disclosures are reviewed for conflicts of interest by the editorial group. When found, these are addressed by vetting through a multi-level review process, and through requirements for references to be provided to support the content. Appropriately referenced content is required of all authors and must conform to UpToDate standards of evidence.
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All topics are updated as new evidence becomes available and our peer review process is complete. Literature review current through: Jul 2015. | This topic last updated: Jan 30, 2014.
INTRODUCTION — Croup (laryngotracheitis) is a
respiratory illness characterized by inspiratory stridor,
barking cough, and hoarseness. It typically occurs in
children six months to three years of age and is caused
by parainfluenza virus. (See "Croup: Clinical features,
evaluation, and diagnosis".)
The treatment of croup has changed significantly since
the 1980s. Glucocorticoids and
nebulized epinephrine have become the cornerstones of
therapy. Substantial clinical evidence supports the
efficacy of these interventions [1-5]. The impact also is
evident in the decrease in annual hospital admissions for
croup in children in the United States between 1979 to
1982 and 1994 to 1997 (from 2.8 to 2.1 per 1000 for
children <1 year and from 1.8 to 1.2 per 1000 children
for children 1 to 4 years) [6].
Treatment of croup may involve a variety of
pharmacologic and nonpharmacologic interventions. It
may occur entirely at home, or in the office, emergency
department (ED), or hospital setting. Supportive and
pharmacologic interventions will be discussed below.
The clinical features and evaluation of croup and the
approach to management are discussed separately.
(See "Croup: Clinical features, evaluation, and
diagnosis" and "Croup: Approach to management".)
GLUCOCORTICOIDS — Glucocorticoids provide long-
lasting and effective treatment of mild, moderate, and
severe croup [3,7-9]. The antiinflammatory actions of
glucocorticoids are thought to decrease edema in the
laryngeal mucosa of children with croup. Improvement is
usually evident within six hours of administration but
seldom is dramatic [7,10].
Treatment with glucocorticoids at various doses and by
various routes has been shown to improve croup scores
and to decrease unscheduled medical visits, length of
stay in the emergency department or hospital, and the
use of epinephrine [7]. Among the available
glucocorticoids, dexamethasone has been used most
frequently, is the least expensive, has the longest
duration of action, and is the easiest to administer.
Efficacy — Intramuscular (IM), intravenous (IV), oral,
and inhaled routes of administration of glucocorticoids
have been shown to be effective in croup of all levels of
severity [7,8]. Dexamethasone (oral or IM)
and budesonide (inhaled) were the agents used in the
majority of studies. A systematic review included 24
trials (with collective enrollment of 2878 children) that
objectively measured the effectiveness of glucocorticoid
treatment for croup compared with placebo [7]. Fourteen
other trials compared different glucocorticoid agents or
different routes or dosages of the same agent [7].
Compared with treatment with placebo, treatment with
glucocorticoid was associated with:
●Improvement in the croup score at six hours with
a weighted mean difference of -1.2 (95% CI -1.6 to
-0.8) and at 12 hours -1.9 (95% CI -2.4 to -1.3); at
24 hours this improvement was no longer
significant (-1.3, 95% CI -2.7-0.2)
●Fewer return visits and/or (re)admissions (relative
risk 0.50, 95% CI 0.3-0.7)
●Decreased length of time spent in emergency
department or hospital (weighted mean difference
12 hours, 95% CI 5-19 hours)
●Decreased use of epinephrine (risk difference 10
percent; 95% CI 1-20 percent)
●There were no significant differences in clinical
efficacy between the routes or agents, and the
combination of oral or IM dexamethasone with
inhaled budesonidewas not superior to either agent
alone [11,12].
Another systematic review of eight randomized
controlled trials compared the administration of
nebulized glucocorticoids with placebo. Children treated
with nebulized glucocorticoids were significantly more
likely to show improvement in croup score at five hours
(combined relative risk (RR) 1.48, 95% CI 1.27-1.74)
and significantly less likely to need hospital admission
(combined RR 0.56, 95% CI 0.42-0.75) [13].
Adverse effects — Few serious adverse effects have
been reported in the studies evaluating the efficacy of
a single dose of glucocorticoids in croup [14]. However,
most of these studies were too small to sufficiently
evaluate rare (<1 percent) adverse effects [15,16].
The primary concern is potential risk of progressive viral
infection or secondary bacterial infection, which have
been reported in patients who received glucocorticoid
treatment over several days [16], or received
nebulized dexamethasone and had neutropenia [17].
These complications have not been described in children
who have received single doses of oral, intramuscular,
or intravenous glucocorticoids for croup.
Glucocorticoid use may exacerbate active varicella and
tuberculosis and should be avoided in children with
these infections and in those recently exposed to, and
possibly incubating, varicella [18,19]. (See "Clinical
features of varicella-zoster virus infection:
Chickenpox" and "Treatment of varicella-zoster virus
infection: Chickenpox".)
Administration of glucocorticoids may mask the
presentation of steroid-responsive upper airway lesions,
such as hemangiomas, which also can present with
stridor, particularly during a viral upper respiratory tract
infection [20]. (See "Epidemiology, pathogenesis, clinical
features, and complications of infantile hemangiomas".)
Agents
Dexamethasone — Dexamethasone may be
administered IM, IV, or orally. To date, no clinically
significant difference in croup outcomes between IM or
orally administered dexamethasone has been
demonstrated [7]. When dexamethasone is administered
IM or IV, a single dose of 0.6 mg/kg (maximum dose of
10 mg) is used most frequently. Smaller doses appear to
be equally effective for mild croup when administered
orally, as illustrated below:
●In one study, 100 children with mild croup were
randomly assigned to receive
oral dexamethasone (0.15 mg/kg) or placebo in the
emergency department [21]. Eight children in the
placebo group, and none in the dexamethasone
group, returned for medical care (a statistically
significant difference).
●In another study, 120 hospitalized children with
croup were randomly assigned to receive a single
oral dose
of dexamethasone (0.15 mg/kg, 0.3 mg/kg, 0.6 mg/
kg) or placebo [22]. There was no difference in
duration of hospitalization, reduction in croup
score, or epinephrine use among the three groups
receiving dexamethasone.
The second study described above [22] included a small
number of children with relatively mild croup and
consequently may have been underpowered (unable) to
detect a clinically important difference, particularly in
children with more severe symptoms [14].
Children with mild croup who can tolerate oral
medications can be given
either dexamethasone 0.15 mg/kg or dexamethasone
0.6 mg/kg orally, to a maximum total dose of 10 mg.
Although the lower 0.15 mg/kg dose appears to be
efficacious [21], we continue to suggest the higher dose
[23,24].
The oral preparation of dexamethasone (1 mg per mL)
has a foul taste. The intravenous preparation is more
concentrated (4 mg per mL) and can be given orally
mixed with syrup [11,25,26].
Studies of nebulized dexamethasone in children with
croup have mixed results. One study found nebulized
dexamethasone to be less effective than oral
dexamethasone in preventing the need for subsequent
treatment with glucocorticoid or epinephrine in children
with mild croup [27]. Another study found that treatment
with nebulized dexamethasone in children with moderate
croup improved croup scores at four hours but did not
affect the rate of hospitalization [17]. In addition, two
patients with neutropenia who were treated with
dexamethasone developed bacterial tracheitis.
Budesonide — Nebulized budesonide has been shown
to be more effective than placebo and as effective as IM
or oral dexamethasone for the treatment of croup [7,28].
However, nebulized budesonide is more expensive and
more difficult to administer than IM or oral
dexamethasone and is not routinely indicated in the
treatment of croup. However, nebulized budesonide may
provide an alternative to IM or IV dexamethasone for
children with vomiting or severe respiratory distress [24].
In children with severe respiratory distress, a single dose
of budesonide may be mixed with epinephrine and
administered simultaneously. (See "Croup: Approach to
management", section on 'Moderate to severe croup'.)
Prednisolone — Some authorities suggest that for
children who are treated as outpatients,
oral prednisolone (2 mg/kg per day for three days) is an
alternative to oraldexamethasone [29]. The use of
prednisolone in the treatment of croup has been
evaluated in a limited number of studies.
A 2011 meta-analysis of two trials [30,31] that compared
a single dose of oral dexamethasone (0.6 mg/kg or
0.15 mg/kg) with a single dose of
oral prednisolone (1 mg/kg)showed no difference in
croup scores, but children randomized to receive
dexamethasone had fewer return
visits and/or subsequent admissions (9.6 versus 29.7
percent, RR 0.3, 95% CI 0.2-0.6) [7].
A subsequent randomized trial compared
oral dexamethasone (0.6 mg/kg on the first day followed
by placebo on the next two days) with
oral prednisolone (2 mg/kg per day for three days) in 87
children with mild or moderate croup who were treated
as outpatients [29]. There were no differences between
groups in additional health care visits (2 versus 7
percent [not significant]), duration of symptoms (2.8
versus 2.2 days), duration of nonbarky cough (6.1
versus 5.9 days), nights with disturbed parental sleep
(0.7 versus 1.2), or days with stress (1.6 versus 1.4).
Another study of 70 children
compared prednisolone (1 mg/kg every 12 hours) with
placebo in children with croup who were already
intubated [8]. Children who received prednisolone had a
shorter median duration of intubation than those in the
placebo group (98 versus 138 hours). In addition, fewer
children in the prednisolone group required reintubation
(5 versus 34 percent).
Prednisone — The use of prednisone in the
management of croup has not been evaluated in clinical
trials. However, it has equivalent potency
to prednisolone and, in theory, should have similar
effects. Despite its lack of proven benefit, prednisone is
widely used in the outpatient management of croup [32].
If prednisone is to be used, it is important to administer a
dose that is equivalent in strength to the doses of
glucocorticoids that have been better
studied. Dexamethasonehas 6.67 times the
glucocorticoid potency of prednisone (4 mg/kg of
prednisone = 0.6 mg/kg of dexamethasone; 2 mg/kg of
prednisone = 0.3 mg/kg of dexamethasone; and
1 mg/kg of prednisone = 0.15 mg/kg of dexamethasone).
If choosing to use the higher dose (ie, 4 mg/kg of
prednisone), the volume required may be prohibitive
given that the concentration of the oral solution of
prednisone is 1 mg/1 mL.
Betamethasone — A pilot study compared the
effectiveness of a single oral dose
of betamethasone (0.4 mg/kg) with a single dose of
IM dexamethasone (0.6 mg/kg)in 52 children (six months
to six years) with mild to moderate croup who were
treated in the emergency department [33]. Despite
randomization, mean baseline croup scores were higher
in the dexamethasone group (3.6 versus 2). Croup
scores declined significantly in both groups, and there
were no differences between groups in mean croup
scores four hours after treatment, rate of hospitalization,
time to resolution of symptoms, need for additional
treatment, or number of return visits to the emergency
department.
Repeated dosing — The majority of clinical trials of oral
and IM glucocorticoids in croup have used a single dose.
Repeat doses are not necessary on a routine basis.
Although repeat doses may be reasonable in the
occasional child who has persistent symptoms, they
should be used with caution. The anecdotal cases of
progression of viral illness and secondary bacterial
infection that have been reported with use of
glucocorticoids for croup occurred with repeated dosing
over several days [34], or in neutropenic patients [17].
(See 'Adverse effects' above.)
Moderate to severe symptoms that persist for more than
a few days should prompt investigation for other causes
of airway obstruction. (See "Croup: Clinical features,
evaluation, and diagnosis", section on 'Differential
diagnosis'.)
NEBULIZED EPINEPHRINE — The administration of
nebulized epinephrine to patients with moderate to
severe croup often results in rapid improvement of upper
airway obstruction. Epinephrine constricts precapillary
arterioles in the upper airway mucosa and decreases
capillary hydrostatic pressure, leading to fluid resorption
and improvement in airway edema [18]. Even a modest
increase in airway diameter can lead to significant
clinical improvement.
Benefits — Several small randomized controlled trials
and a meta-analysis have demonstrated the benefit of
racemic epinephrine compared with placebo in reducing
the croup scores 30 minutes after treatment in children
in the emergency department, hospital, and intensive
care unit [1,35-37]. The magnitude of reduction in mean
croup score from baseline ranged from 2.2 to 3.6 at 20
to 30 minutes (compared with approximately 1 in the
placebo group). However, by 120 minutes, croup scores
returned to baseline or near baseline [1,36]. In one trial,
treatment with IM dexamethasone and nebulized
epinephrine was associated with decreased duration of
hospitalization compared with IM dexamethasone and
placebo (-32 hours, 95% CI -59.1 to -4.9) [38,39].
Administration of epinephrine does not alter the natural
history of croup in the short (>2 hours) or longer term (24
to 36 hours) [1,36,39].
In the studies described above, racemic epinephrine was
administered either by nebulization alone or by
nebulization combined with intermittent positive pressure
breaths [1,35,36]. Another study compared these two
methods of administration and found them to be similarly
effective [2].
Racemic versus L-epinephrine —
Racemic epinephrine, which is a 1:1 mixture of the D-
and L-isomers, was initially thought to produce fewer
systemic side effects, such as tachycardia and
hypertension [18]. However, a randomized double-blind
study comparing racemic epinephrine and L-epinephrine
in children with croup found no difference between the
two preparations in 30-minute croup score, heart rate,
blood pressure, respiratory rate, fraction of inspired
oxygen, or oxygen saturation [40]. This finding is
particularly important outside of the United States, where
racemic epinephrine is not readily available. Either form
of epinephrine is acceptable to use in the United States.
Dose
●Racemic epinephrine is administered as
0.05 mL/kg per dose (maximum of 0.5 mL) of a
2.25 percent solution diluted to 3 mL total volume
with normal saline. It is given via nebulizer over 15
minutes.
●L-epinephrine is administered as 0.5 mL/kg per
dose (maximum of 5 mL) of a 1:1000 dilution [40].
It is given via nebulizer over 15 minutes.
Nebulized epinephrine treatments may be repeated
every 15 to 20 minutes if warranted by the clinical
course. Children who require repeated frequent dosing
(eg, three or more doses within two to three hours) to
achieve stabilization of their respiratory function
generally should be admitted to an intensive care unit or
intermediate care setting (depending on the severity of
persisting signs).
Precautions — The clinical effects of
nebulized epinephrine last for no more than two hours.
After the effects have worn off, symptoms may return to
baseline (an apparent worsening, sometimes referred to
as the "rebound phenomenon"). Children who receive
even a single dose of nebulized epinephrine should be
observed in the emergency department or hospital
setting for at least three to four hours after administration
to ensure that symptoms do not return to baseline.
Serious adverse effects from nebulized epinephrine are
exceedingly rare. However, a case of myocardial
infarction in a child with croup who received three doses
of racemic epinephrine within 60 minutes has been
reported [41]. Thus, it seems prudent to place children
who require ongoing epinephrine treatments more
frequently than every one to two hours on cardiac
monitors (both because of the severity of illness and the
potential systemic impact of nebulized epinephrine).
Continuous electrocardiographic monitoring (or
equivalent cardiac monitoring) also should be
considered in these cases.
OXYGEN — Oxygen is not known to have any direct
impact on the subglottic edema or airway narrowing, but
should be administered to children who are hypoxemic
(oxygen saturation of <92 percent in room air) and/or in
moderate to severe respiratory distress [14,24].
Supplemental oxygen should be humidified to decrease
drying effects on the airways, since drying may impede
the physiologic removal of airway secretions via
mucociliary and cough mechanisms. (See "Continuous
oxygen delivery systems for infants, children, and
adults".)
Heliox — Helium is inert, nontoxic, and of very low
density. Heliox is a mixture of helium (70 to 80 percent)
and oxygen (20 to 30 percent). It can flow through
airways with less turbulence and resistance than pure
oxygen. (See "Physiology and clinical use of heliox".)
Heliox decreases the work of respiration in children with
croup and theoretically could be used as a temporizing
measure, to prevent the need for intubation while waiting
for glucocorticoids to decrease airway edema [42].
However, in clinical trials, heliox has not definitively been
shown to be more effective than humidified oxygen or
racemic epinephrine in reducing croup scores [43-45]. A
2013 systematic review found only three
methodologically limited trials (91 patients) evaluating
heliox in children with croup and concluded that a larger
trial is needed before recommendations regarding the
use of heliox in children with croup can be made [45].
MIST THERAPY — Humidified air is frequently used in
the treatment of croup, although there have been no
studies supporting its efficacy in reducing symptoms
[46]. Two randomized trials (one comparing mist versus
no mist and the other comparing no mist, low humidity,
and 100 percent humidity) among children brought to an
emergency department for croup demonstrated no
significant change in croup scores from baseline
between the groups [47,48].
Although humidified air does not reduce subglottic
edema, it may provide other benefits. Inhalation of moist
air, relative to dry air, may decrease drying of inflamed
mucosal surfaces and reduce inspissation of secretions
[49]. In addition, a mist source may provide a sense of
comfort and reassurance to both the child and family
[50-52]. In medical settings, mist therapy may be
provided by blow-by or saline nebulization treatments.
Croup tents should be avoided, since they can
aggravate a child's anxiety and make vital signs and
other visual assessments of the child more difficult.
Some guidelines recommend against the use of mist
therapy for children who are hospitalized with croup [24].
Certainly if the child is agitated by the provision of mist,
mist therapy should be discontinued.
OTHER THERAPIES
Antibiotics — Antibiotics have no role in the routine
management of uncomplicated croup, since most cases
are caused by viruses [14]. Antibiotics should be used
only to treat specific bacterial complications, such as
tracheitis.
Antitussives — Nonprescription antitussive agents are
of unproven benefit for croup (or other respiratory tract
infections). Codeine, which is a more potent cough
suppressant, can alter the child's sensorium, making it
difficult to follow the clinical course.
Decongestants — Decongestants also are of unproven
benefit for croup [14,24].
Sedatives — The routine use of sedative agents in effort
to improve airway obstruction by relieving anxiety and
apprehension is not recommended. Sedatives may treat
the symptom of agitation while masking the underlying
causes of air hunger and hypoxia. They also may
decrease respiratory effort (and therefore croup scores),
without improving ventilation [14,53].
INFORMATION FOR PATIENTS — UpToDate offers
two types of patient education materials, “The Basics”
and “Beyond the Basics.” The Basics patient education
pieces are written in plain language, at the 5th to
6th grade reading level, and they answer the four or five
key questions a patient might have about a given
condition. These articles are best for patients who want
a general overview and who prefer short, easy-to-read
materials. Beyond the Basics patient education pieces
are longer, more sophisticated, and more detailed.
These articles are written at the 10th to 12
th grade
reading level and are best for patients who want in-depth
information and are comfortable with some medical
jargon.
Here are the patient education articles that are relevant
to this topic. We encourage you to print or e-mail these
topics to your patients. (You can also locate patient
education articles on a variety of subjects by searching
on “patient info” and the keyword(s) of interest.)
●Basics topic (see "Patient information: Croup (The
Basics)")
●Beyond the Basics topic (see "Patient information:
Croup in infants and children (Beyond the Basics)")
SUMMARY
●Treatment with glucocorticoids (oral,
intramuscular, or nebulized) has been shown to
decrease croup scores, unscheduled medical
visits, length of stay in the emergency department
or hospital, and the use of epinephrine. A single
dose of oral or intramuscular dexamethasone is
appropriate and adequate for most children.
(See 'Glucocorticoids' above and "Croup: Approach
to management", section on 'Initial treatment'.)
●Treatment with nebulized epinephrine results in
rapid improvement of upper airway obstruction, but
the duration of effect is less than two hours.
Racemic epinephrine and L-epinephrine appear to
be equally effective. (See 'Nebulized
epinephrine' above.)
●Humidified air is frequently used as a supportive
treatment for croup; however, there have been no
studies supporting its efficacy in reducing
symptoms. (See 'Mist therapy' above.)
●Humidified oxygen should be administered to
children who are hypoxemic and/or in moderate to
severe respiratory distress. (See 'Oxygen' above.)
●Heliox has not definitively been shown to be more
effective than humidified oxygen or
racemic epinephrine in reducing croup scores.
(See 'Heliox' above.)
●Antibiotics should be used only to treat specific
bacterial complications of croup.
(See 'Antibiotics' above and "Croup: Approach to
management", section on 'Complications'.)
●Antitussives and decongestants are of unproven
benefit in the management of croup. Sedatives
may decrease the work of breathing and improve
agitation without actually improving ventilation or
addressing the underlying cause of agitation
(hypoxemia). (See 'Other therapies' above.)
Use of UpToDate is subject to the Subscription and License Agreement.
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