kongjungtivitis viral
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Practice Essentials
Viral conjunctivitis, or pinkeye (see the image below), is a common, self-limiting condition
that is typically caused by adenovirus. Other viruses that can be responsible for conjunctival
infection include herpes simplex virus (HSV), varicella-zoster virus (VZV), picornavirus
(enterovirus 70, Coxsackie A24), poxvirus (molluscum contagiosum, vaccinia), and human
immunodeficiency virus (HIV).
Viral conjunctivitis. Image courtesy of Wikimedia Commons.
Viral conjunctivitis is highly contagious, usually for 10-12 days from onset as long as the
eyes are red. Patients should avoid touching their eyes, shaking hands, and sharing towels,
among other activities. Transmission may occur through accidental inoculation of viral
particles from the patient's hands or by contact with infected upper respiratory droplets,
fomites, or contaminated swimming pools. The infection usually resolves spontaneously
within 2-4 weeks.
Signs and symptoms
Signs and symptoms of viral conjunctivitis may include the following:
Itchy eyes
Tearing
Redness
Discharge
Light sensitivity (with corneal involvement)
See Clinical Presentation for more details.
Diagnosis
Generally, a diagnosis of viral conjunctivitis is made on the clinical features alone. Lab tests
are typically not necessary, but they may be helpful in some cases. Specimens can be
obtained by culture and smear if inflammation is severe, in chronic or recurrent infections,
with atypical conjunctival reactions, and in patients who fail to respond to treatment. Giemsa
staining of conjunctival scrapings may aid in characterizing the inflammatory response.
See Workup for more details.
Management
Treatment of adenoviral conjunctivitis is supportive. Patients should be instructed to use cold
compresses and lubricants, such as artificial tears, for comfort. Topical vasoconstrictors and
antihistamines may be used for severe itching but generally are not indicated. For patients
who may be susceptible, a topical astringent or antibiotic may be used to prevent bacterial
superinfection.
Virus-specific treatments
Patients with conjunctivitis caused by HSV usually are treated with topical antiviral agents,
including idoxuridine solution and ointment, vidarabine ointment, and trifluridine solution.
Treatment of VZV eye disease includes oral acyclovir to terminate viral replication.
For conjunctivitis associated with molluscum contagiosum, disease will persist until the skin
lesion is treated. Removal of the central core of the lesion or inducement of bleeding within
the lesion usually is enough to cure the infection.
Prevention
Preventing transmission of viral conjunctivitis is important. Both patient and provider should
wash hands thoroughly and often, keep hands away from the infected eye, and avoid sharing
towels, linens, and cosmetics. Infected patients should be advised to stay home from school
and work. Those who wear contact lenses should be instructed to discontinue lens wear until
signs and symptoms have resolved.
See Treatment and Medication for more details.
Viruses are a common cause of conjunctivitis in patients of all ages. A variety of viruses can
be responsible for conjunctival infection; however, adenovirus is by far the most common
cause, and herpes simplex virus (HSV) is the most problematic. Less common causes include
varicella-zoster virus (VZV), picornavirus (enterovirus 70, Coxsackie
A24), poxvirus (molluscum contagiosum, vaccinia), and human immunodeficiency virus
(HIV). Rarely, conjunctivitis is seen during systemic infection with influenza virus, Epstein-
Barr virus, paramyxovirus (measles, mumps, Newcastle), or rubella. (See Etiology.)[1]
Viral conjunctivitis, although usually benign and self-limited, tends to follow a longer course
than acute bacterial conjunctivitis, lasting for approximately 2-4 weeks. Viral infection is
characterized commonly by an acute follicular conjunctival reaction and preauricular
adenopathy. (See History and Physical Examination.)
Etiology
Adenoviral conjunctivitis is the most common cause of viral conjunctivitis. Particular
subtypes of adenoviral conjunctivitis include epidemic keratoconjunctivitis (pink eye) and
pharyngoconjunctival fever.
Viral conjunctivitis is highly contagious, usually for 10-12 days from onset as long as the
eyes are red. Patients should avoid touching their eyes, shaking hands, and sharing towels,
among other activities. Transmission may occur through accidental inoculation of viral
particles from the patient's hands or by contact with infected upper respiratory droplets,
fomites, or contaminated swimming pools.
Primary ocular herpes simplex infection is common in children and usually is associated with
a follicular conjunctivitis. Infection usually is caused by HSV type I, although HSV type II
may be a cause, especially in neonates. Recurrent infection, typically seen in adults, usually is
associated with corneal involvement.
VZV can affect the conjunctiva during primary infection (chickenpox) or secondary infection
(zoster). Infection can be caused by direct contact with VZV or zoster skin lesions or by
inhalation of infectious respiratory secretions.
Picornaviruses cause an acute hemorrhagic conjunctivitis that is clinically similar to
adenoviral conjunctivitis but is more severe and hemorrhagic. Infection is highly contagious
and occurs in epidemics.
Molluscum contagiosum may produce a chronic follicular conjunctivitis that occurs
secondary to shedding of viral particles into the conjunctival sac from an irritative eyelid
lesion.
Vaccinia virus has become a rare cause of conjunctivitis because, with the elimination of
smallpox, the vaccination rarely is administered. Infection occurs through accidental
inoculation of viral particles from the patient's hands.
HIV is the etiologic agent of acquired immunodeficiency syndrome (AIDS). Ocular
abnormalities in patients with AIDS primarily affect the posterior segment, but anterior
segment findings have been reported. When conjunctivitis occurs in a patient with AIDS, it
tends to follow a more severe and prolonged course than in patients without AIDS. In
general, patients with AIDS may develop a transient, nonspecific conjunctivitis, characterized
by irritation, hyperemia, and tearing, that requires no specific treatment. Microsporidia has
been isolated from the cornea and conjunctiva of several patients with AIDS
and keratoconjunctivitis. In these patients, symptoms included foreign body sensation,
blurred vision, and photophobia; most cases resolved without antimicrobial therapy.
Epidemiology
US and international occurrence
Viral conjunctivitis is a common ocular disease in the United States and worldwide. Because
it is so common, and because many cases are not brought to medical attention, accurate
statistics on the frequency of the disease are unavailable. Viral infection frequently occurs in
epidemics within families, schools, offices, and military organizations.
Sex predilection
Viral conjunctivitis can occur equally in men and women.
Age predilection
Viral conjunctivitis can affect all age groups, depending on the specific viral etiology.
Usually, adenovirus affects patients aged 20-40 years. HSV and primary VZV infection
usually affect young children and infants. Herpes zoster ophthalmicus results from
reactivation of latent VZV infection and may present in any age group. Typically, the
picornaviruses affect children and young adults in the lower socioeconomic classes.[2]
Prognosis
Most cases of viral conjunctivitis are acute, benign, and self-limited, although chronic
infections have been reported. Long-term ocular sequelae are uncommon. The infection
usually resolves spontaneously within 2-4 weeks. Subepithelial infiltrates may last for several
months, and, if in the visual axis, they may cause decreased vision or glare.
Morbidity
Complications include the following: punctate keratitis with subepithelial infiltrates, bacterial
superinfection, corneal ulceration with keratoconjunctivitis, and chronic infection.
Epithelial keratitis may accompany viral conjunctivitis. Punctate epithelial erosions that stain
with fluorescein are commonly associated with viral keratitis. Rarely, these changes are
sufficiently distinctive morphologically to allow identification of a specific type of virus as
the etiologic agent. If the conjunctivitis persists or is severe, disturbances in the anterior
stroma beneath the epithelial abnormalities may occur. In general, the stromal or subepithelial
abnormalities are transient and resolve despite persistence of epithelial keratitis. However, in
cases of adenoviral infection, the stromal abnormalities may persist for months to years, long
after the epithelial changes have resolved. In such cases, these subepithelial infiltrates are
considered to be immunologic in origin, the result of antigen-antibody reaction. If they are in
the pupillary axis, they may cause decreased vision and/or glare.
Medication Summary
Medications used in the treatment of viral conjunctivitis include the following:
Topical artificial tears - 4-8 times per day, for 1-3 weeks
Topical vasoconstrictor/antihistamine - 4 times per day, for severe itching
Topical steroiAntihistamines
Class Summary
These agents are used to treat severe itching.
Levocabastine
Levocabastine is a potent histamine H1-receptor antagonist; it is for
ophthalmic use.
ds - For pseudomembranes and subepithelial infiltrates
Topical antibiotic - To prevent bacterial superinfection
Topical antiviral agents - For HSV infection
Antivirals
Class Summary
These agents are used for the treatment of HSV infection.
View full drug information
Trifluridine (Viroptic)
Trifluridine is a pyrimidine (thymidine) analogue drug of choice in the United States
for topical antiviral therapy for HSV infection. It inhibits viral replication by
incorporating into viral deoxyribonucleic acid (DNA) in place of thymidine. If the
patient has no response in 7-14 days, consider other treatments.
View full drug information
Acyclovir (Zovirax)
This is a prodrug that inhibits viral replication; it is activated by phosphorylation by
virus-specific thymidine kinase.
Oral acyclovir - For VZV infection
Corticosteroids
Class Summary
Corticosteroids may be used for pseudomembranes and decreased vision
and/or glare due to subepithelial infiltrates. They have anti-inflammatory
properties and cause profound and varied metabolic effects. In addition, these
agents modify the body's immune response to diverse stimuli. Extreme caution
should be taken when using corticosteroids, as they may worsen an underlying
HSV infection.
View full drug information
Prednisolone ophthalmic (AK-Pred, Pred Mild, Omnipred)
This agent decreases inflammation by suppressing migration of
polymorphonuclear leukocytes and reversing increased capillary permeability.
Less potent (eg, prednisolone 0.125%, fluorometholone 0.1%) are usually
sufficient to treat subepithelial infiltrates. The steroid must be tapered very
slowly, over months.
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Next Section: Antivir
Patient Education
To allay patient anxiety, it is helpful to inform patients that their symptoms
may worsen during the first 4-7 days after onset before they begin to improve
and may not resolve for 2-4 weeks. The contagiousness of the infection also
should be emphasized. Proper isolation from the workplace or school is
advisable to prevent epidemics.
Patients with conjunctivitis who wear contact lenses should be instructed to
discontinue lens wear until signs and symptoms have resolved.
For patient education information, see the Eye and Vision Center and the Skin,
Hair, and Nails Center, as well as Pinkeye, How to Instill Your Eyedrops,
andMolluscum Contagiosum.
Diagnostic Considerations
Allergic conjunctivitis must be differentiated from viral and bacterial conjunctivitis. Clinical features (eg, recent exposure to an individual with infective conjunctivitis) may be helpful in this regard.
The main distinction between seasonal and perennial allergic conjunctivitis, as implied by the names, is the timing of symptoms (see Pathophysiology). Major differentiating factors between vernal keratoconjunctivitis (VKC) and atopic keratoconjunctivitis (AKC) are shown in the table below.
Table. Major Differentiating Factors Between VKC and AKC (Open Table in a new window)
Characteristics VKC AKC
Age at onset Generally presents at a younger age than AKC -
Sex Males are affected preferentially. No sex predilection
Seasonal variation Typically occurs during spring months Generally perennial
Discharge Thick mucoid discharge Watery and clear discharge
Conjunctival scarring - Higher incidence of conjunctival scarring
Horner-Trantas dots Horner-Trantas dots and shield ulcers are commonly seen.
Presence of Horner-Trantas dots is rare.
Corneal neovascularization Not present Deep corneal neovascularization tends to develop
Presence of eosinophils in conjunctival scraping
Conjunctival scraping reveals eosinophils to a greater degree in VKC than in AKC
Presence of eosinophils is less likely
Differential Diagnoses Conjunctivitis, Bacterial Conjunctivitis, Giant Papillary Conjunctivitis, Viral Keratoconjunctivitis, Atopic Keratoconjunctivitis, Superior Limbic Keratoconus
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