insect allergy
DESCRIPTION
definition ,pathology ,diagnosis ,treatment,TRANSCRIPT
Insect AllergyProf. Dr. Saad S Al Ani
Senior Pediatric ConsultantHead of Pediatric Department
Khorfakkan hospitalSharjah ,[email protected]
April 12, 2023 2
HistoryThe first reports of stinging
insect allergy came from the Middle East thousands of years ago.
Even at that time, people understood that a small insect, such as a bee or a wasp, had the potential to cause serious illness or even death.
http://www.theonlineallergist.com
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 3
Introduction
Allergic responses to stinging
1. Localized cutaneous reactions
2. Systemic anaphylaxis
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 4
Cont.
Allergic reactions that are caused by inhalation of airborne particles of insect origin result in:
1. Acute or 2.Chronic respiratory symptoms of
seasonal or perennial: i. Rhinitis ii. Conjunctivitis iii. Asthma
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 5
Etiology
Most reactions to biting and stinging insects, such as those induced by mosquitoes, flies, and fleas, are limited to a primary lesion isolated to the area of the bite and do not represent an allergic response.
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 6
Cont.
Occasionally, insect bites or stings induce pronounced localized reactions or systemic reactions that may be based on:
1. Immediate or 2.
Delayed hypersensitivity reactions.Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 7
Cont.
Systemic allergic responses to insects are attributed most typically to immunoglobulin (Ig)E antibody–mediated responses, which are caused:
i. Primarily by stings from venomous insects of the order Hymenoptera
ii. More rarely from ticks, spiders, and kissing bug.
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 8
Cont.
Systemic reactions to stinging insects occur in 0.4-0.8% of children and 3% of adults
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 9
Cont.
Members of the order Hymenoptera include:
i. Apids: * Honeybee *
Bumblebee ii. Vespids * Yellow jacket *
Wasp * Hornet iii. Formicids * Fire ants *
Harvester ants
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 10
Species of Hymenoptera and their geographical distribution.
Freeman TM: Hypersensitivity Hymenoptera stings, N Engl J Med 351:1978–1984, 2004.)
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 11
Cont.
Freeman TM: Hypersensitivity Hymenoptera stings, N Engl J Med 351:1978–1984, 2004.)
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 12
Pathogenesis
Localized skin responses to biting insects are caused primarily by vasoactive or irritant materials derived from insect saliva, and rarely occur from IgE-associated responses
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 13
Cont.
Systemic IgE-mediated allergic reactions to salivary proteins of biting insects such as mosquitoes are reported but uncommon.
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 14
Cont.
IgE antibody–mediated allergic responses to airborne particulate matter carrying insect emanations contribute to:
1. Seasonal 2. Perennial symptoms affecting the
upper and lower airways
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 15
Seasonal allergy
Attributed to exposures to a variety of insects, particularly aquatic insects such as the caddis fly and midge, or lake fly, at a time when larvae pupate and adult flies are airborne
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 16
Perennial allergy
Attributed to sensitization to insects such as cockroaches and ladybugs as well as house dust mite
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 17
Hymenoptera venoms
Contain numerous components with toxic and harmacologic activity and with allergenic potential.
These constituents include: 1.Vasoactive substances such as histamine, acetylcholine, and kinins 2.Enzymes such as phospholipase and hyaluronidase 3.Apamin4. Melittin5. formic acid
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 18
Cont.
The majority of patients who experience systemic reactions after Hymenoptera stings have IgE-mediated sensitivity to antigenic substances in the venom.
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 19
i. Honey bees are only capable of stinging a person once.
Honey Bee
iii. As the honey bee flies away, it become eviscerated and dies.
ii. The honey bee is the only stinging insect that leaves its stinger and venom sac in the skin of its victim, due to the barbed configuration of the stinger.
http://www.theonlineallergist.comInsect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 20
Yellow Jacket
i. Wasp-like insects that live in mounds built into the ground
iii. They are commonly found around garbage cans and picnic areas where food and sugary drinks are abundant
ii. They tend to be very aggressive insects, and will often sting without provocation.
http://www.theonlineallergist.com
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 21
Hornet
Hornets, including yellow and white-faced hornets, build paper- mache type nests in trees and shrubs
Some hornets look very much like yellow jackets and can be difficult to distinguish
These insects may be very aggressive, and a sting may be provoked by a minor disruption in their environment.
http://www.theonlineallergist.com
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 22
Wasps
Wasps build honey-comb nests under the eaves of a house, or in a tree, shrub or under patio furniture.
They tend to be less aggressive than yellow jackets and hornets, and mostly feed on insects and flower nectar.http://science.howstuffworks.com
http://www.theonlineallergist.com
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
23
Bumblebees
Bumblebees rarely sting people because they are non-aggressive and typically mild mannered
They generally will sting only if provoked
They nest in the ground or in piles of grass clippings or wood
http://www.theonlineallergist.com
April 12, 2023 24
Fire Ant
Fire Ant bites are generally quite painful
The bite of a fire ant characteristically Will form into a white pustule within a day or twoScratching these pustules can lead to local infection and scars
It is not unusual to sustain multiple bites, generally on the feet and hands
http://www.theonlineallergist.com
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 25
Clinical Manifestations
Insect bites are usually urticarial but may be papular or vesicular
Papular urticaria affecting the lower extremities in children is usually caused by multiple bites
IgE antibody–associated immediate- and late-phase allergic responses to mosquito bites sometimes mimic cellulitis
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 26
Clinical reactions to stinging venomous insectsAre categorized
as:
6.Delayed/Late
1. Local
2. Large local
3. Generalized cutaneous
4. Systemic
5. toxic
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 27
Cont.1.Simple local reactions i. Involve limited
swelling ii. Pain iii. Generally last
<24 hr. 2.Large local reactions i. Develop over hours and days ii. involve swelling of extensive areas (>10 cm) that are contiguous with the sting site iii. May last for days
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 28
Cont.3.Generalized cutaneous
reactions Typically progress within
minutes and include cutaneous symptoms of :
i. Urticaria ii. Angioedema iii. Pruritus beyond the site of the sting 4.Systemic reactions are identical to anaphylaxis from other triggers and may include symptoms of : i. Generalized urticaria ii .Laryngeal edema iii. Bronchospasm iv. HypotensionInsect Allergy Prof. Dr. Saad S Al Ani
Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 29
Cont.5. Toxic reactions Stings from a large number of
insects at once may result in toxic reactions of :
i. Fever ii. Malaise iii. Emesis iv. Nausea owing to the chemical properties of the venom in large doses.6.Delayed/Late reactions
i. Serum sickness ii. Nephrotic syndrome iii. Vasculitis iv. Neuritis v. Encephalopathy may occur as delayed/late reactions to stinging insectsInsect Allergy Prof. Dr. Saad S Al Ani
Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 30
Inhalant allergy
Caused by insects results in clinical disease similar to that induced by other inhalant allergens such as pollens
Depending on individual sensitivity and exposure, reactions may result in seasonal or perennial rhinitis, conjunctivitis, and asthma
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 31
Diagnosis
Generally evident from: i. History of
exposure ii. Typical
symptoms iii. Physical
findings
The diagnosis of Hymenoptera allergy rests in part on the identification of venom-specific IgE by prick skin testing
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 32
Cont.
The primary reasons to pursue testing are to confirm reactivity when: i. Venom immunotherapy (VIT) is being considered ii. It is clinically necessary to confirm venom hypersensitivity as a cause of a reaction
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 33
Cont.Venoms of five Hymenoptera (
1.Honeybee 2.Yellow jacket 3. Yellow hornet 4. White-faced hornet 5. Wasp) as well as the jack jumper ant and whole-body extract of fire ant are available for skin testing
Skin tests are usually accurate within 1 wk of a sting reaction, but occasionally a refractory period is observed that warrants retesting after 4-6 wk if the initial results are negativeInsect Allergy Prof. Dr. Saad S Al Ani
Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 34
The diagnosis of inhalant insect allergyMay be evident from a history of typical symptoms induced seasonally in specific geographic regionsSkin prick or in vitro immunoassay tests for specific IgE to the insect are used to confirm inhalant insect allergy
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 35
Treatment
i. Cold compressesii. Topical medications to relieve itchingiii. occasionally the use of a. systemic antihistamine b. oral analgesic are appropriateStingers should be removed promptly by scraping, with caution not to squeeze the venom sac because doing so could inject more venom
For local cutaneous reactions
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 36
Cont.
Sting sites rarely become infected, possibly owing to the antibacterial actions of venom constituentsVesicles left by fire ant stings that are scratched open should be cleansed to prevent secondary infection
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 37
Cont.
Therapies may include: i. Oxygen ii. Epinephrine iii. Intravenous saline iv. Steroids v. Antihistamines
Anaphylactic reactions
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 38
Venom Immunotherapy(VIT)
Hymenoptera VIT is highly effective (95-97%) in decreasing the risk for severe anaphylaxis. The selection of patients for VIT depends on several factors
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
39
Indications for venom immunotherapy against winged
Hymenoptera SYMPTOMS AGE SKIN TEST/IN VITRO
TEST
RISK OF SYSTEMIC
REACTION IF UNTREATED
(%)*
VIT RECOMMENDE
D
Large local reaction Any Usually not indicated 4-10 Usually not
indicated
Generalized
cutaneous reaction
≤16 yr Usually not indicated 9-10 Usually not indicated
≥17 yrPositive result 20 Yes
Negative result — No
Systemic reaction
Any
Positive result Child: 40Adult: 60-70
Yes
Negative result — Usually no
*Risks generally decrease after 10 yr
April 12, 2023 40
Prevention Avoidance of stings and bites is essential
To reduce the risk of stings, sensitized individuals should: i. Avoid attractants such as perfumes and bright-colored clothing outdoors ii. Wear gloves when gardening iii. Wear long pants and shoes with socks when walking in the grass or through fields
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 41
Cont.
Typical insect repellents do not guard against Hymenoptera. Nests of these insects should be removed if they are close to the home
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 42
Cont.
Individuals who have had generalized cutaneous or systemic reactions to Hymenoptera stings should have immediate access to self- injectable epinephrineThe individual at risk for anaphylaxis from an insect sting should also wear an identification bracelet indicating the allergyInsect Allergy Prof. Dr. Saad S Al Ani
Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 43
Cont.
Avoidance of the insect is the preferred management of inhalant allergyImmunotherapy is occasionally undertaken in such cases, but beneficial results have not been thoroughly documented.
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
April 12, 2023 44
References
Insect Allergy Prof. Dr. Saad S Al Ani Khorfakkan Hospital ,Sharjah ,UAE
1. http://www.acaai.org/allergist/allergies/types/insect-sting-allergies
2. http://www.theonlineallergist.com3. Freeman TM: Hypersensitivity
Hymenoptera stings, N Engl J Med 351:1978–1984, 2004.)
4. http://www.webmd.com/allergies/guide/insect-stings
5. http://www.aaaai.org/conditions-and-treatments/library/allergy-library/stinging-insect-allergy
6. http://science.howstuffworks.com7. Scott H. Sicherer,Donald Y.M. Leung.
Insect Allergy.(In) Robert M. Kliegman, MD, and Richard E. Behrman, MD. Nelson Textbook of Pediatrics - Chapter 140