Reviewer: S. Randhawa, M.D., Allergist/Immunologist and Assistant Professor at NSU
An 18-month-old girl is brought to the allergy clinic by her parents who are worried about adverse reaction to the MMR vaccine recommended by their pediatrician. The girl's cousin is allergic to eggs and she reportedly "developed autism after MMR vaccine". Neither the child nor the parents have any history of allergy.
Past medical history (PMH)
Family medical history (FMH)
Would you do any allergy tests?
No allergy tests are indicated.
Is there an increased risk of allergic reaction to MMR in patients with egg allergy?
No. In 1994, the AAP recommended against MMR immunization in children allergic to eggs. This position was reversed after a study published in the NEJM in 1995 did not show an increased risk of adverse reaction after MMR vaccine in egg-allergic children.
Is it true that egg allergy is no longer considered a contraindication to MMR vaccine?
Several studies have documented the safety of measles and mumps vaccine (which are grown in chick embryo tissue culture) in children with severe egg allergy. Neither the AAP's "Red Book" Committee nor ACIP consider egg allergy as a contraindication to MMR vaccine. ACIP recommends routine vaccination of egg-allergic children without the use of special protocols or desensitization procedures.
Source: National Center for Immunization and Respiratory Diseases (Grant No. 5U38IP000290) at the Centers for Disease Control and Prevention (CDC), http://www.immunize.org/askexperts/experts_mmr.asp
Is there an increased risk of autism after MMR immunization?
The scientific evidence does not support a causative relationship between MMR immunization and autism.
After the patient family were informed of the scientific evidence, they agreed to proceed with MMR immunization.
What did we learn from this case?
There is no increased risk of allergic reaction to MMR in patients with egg allergy.
Eight top allergens account for 90 percent of all food allergies. See more Allergy and Immunology mind maps here.
Egg allergy is one of the most common food allergies in young children.
What is the most common food allergy in children?
Cow's milk allergy is the most common childhood food allergy.
Diagnostic algorithm for food allergy: SAD Child:
1. Symptoms: close relation between specific food intake and symptoms, often affect 2 or more organs
2. Allergy testing: skin prick testing or ImmunoCAP.
3. Diagnostic diet: restricted diet leads to symptoms disappearance or significant reduction.
4. Challenge - oral food challenge.
References: Clinical review: ABC of allergies, Food allergy. BMJ 1998;316:1299, figure.
What is the prognosis of egg allergy?
Majority of children outgrow the egg allergy by school age.
90% of infants allergic to milk and 50 % those allergic to eggs outgrow their clinical reactivity by the age of 3 but most patients allergic to peanuts do not. Therefore, diagnosis should therefore be re-evaluated yearly. There is some evidence that milk and egg allergies are becoming harder to outgrow.
There is a correlation between IgE titres and the severity of clinical reaction to egg after the diagnosis has been established. A cut-off level of 8.20 kU/l had a 90% probability of clinical reactivity. IgE titres may help determine which patients are at risk of a reaction to eggs.
In children, 85% of cow’s milk, egg, wheat, and soy allergy resolves by five years. In contrast, only 20% of children “outgrow” their peanut allergy, and only 9% of tree nut-allergic patients do so.
What is the treatment of egg allergy?
Management of egg allergy involves exclusion of egg from the diet.
There is no current active treatment for food allergy. Traditional injection immunotherapy (SCIT) has been proved unsafe, and therefore there is a need for other forms of immunotherapy. Occasional studies of egg oral immunotherapy (OIT) are currently at the stage of proof of concept.
Potentially life-threatening reactions may arise from immunization with vaccines prepared in eggs.
EpiPen Jr. is life saving in cases of anaphylaxis.
When is diet elimination no longer required in egg allergy?
This decision may be helped by:
- demonstrating loss of sensitivity by skin prick or specific IgE testing
- supervised food challenge
Most children with milk and egg allergy tolerate extensively heated forms of these foods http://goo.gl/Buwu
"True" allergic, or immediate hypersensitivity, reactions to vaccines range from 1 per 50,000 doses for diphtheria-tetanus-pertussis (DTP) to 1 per 500,000 to 1,000,000 doses for most other vaccines.
In the US, the incidence of immediate hypersensitivity reactions to vaccines is 1-2 per 1 million vaccinations. A a true vaccine reaction occurs within the first 2 hours after the shot in 99 percent of the cases.
Some vaccines which include gelatin (e.g., Japanese encephalitis) have a higher rates of serious allergic reactions.
2017 update: Administration of influenza vaccines to egg allergic recipients: A practice parameter update 2017 http://bit.ly/2Ce91gK
Correlation between specific immunoglobulin E levels and the severity of reactions in egg allergic patients. Avigael H. Benhamou, Samuel A. Zamora, Philippe A. Eigenmann. Pediatric Allergy and Immunology 19 (2), 173–179, 2008.An Algorithm for Treatment of Patients With Hypersensitivity Reactions After Vaccines. Robert A. Wood, MD, Melvin Berger, MD, PhD, Stephen C. Dreskin, MD, PhD, Rosanna Setse, MD, MPH, Renata J.M. Engler, MD, Cornelia L. Dekker, MD, Neal A. Halsey, MD, Pediatrics, Vol. 122 No. 3 September 2008, pp. e771-e777.
Egg allergy. Kemp AS. Pediatr Allergy Immunol 2007: 18: 696–702.
Food Allergy: A Short Review. Allergy Cases.
Clinical review: ABC of allergies, Food allergy. BMJ 1998;316:1299, figure.
Egg oral immunotherapy in nonanaphylactic children with egg allergy. JACI, Volume 119, Issue 1, Pages 199-205 (January 2007).
Milk and Egg Allergies Harder To Outgrow, Hopkins Study Shows. Johns Hopkins Children's Center, 01/2008.
Correlation between specific immunoglobulin E levels and the severity of reactions in egg allergic patients. Avigael H. Benhamou, Samuel A. Zamora, Philippe A. Eigenmann. Pediatric Allergy and Immunology 19 (2), 173–179, 2008.
Food Allergen Avoidance. V. Dimov, Oct 2008.
Tolerance to egg-containing baked foods (cake, bread) does not exclude the possibility of egg allergy (AAAAI Ask The Expert).
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