Specific immunoglobulin E (IgE) cut-off levels have been proposed in the past for diagnosis of egg allergy but the IgE levels were not used to predict a reaction to egg in patients with an established diagnosis. Omalizumab binds to Cε3 region of IgE.A Swiss study tried to determine if IgE titres correlate with severity of reactions during a standardized egg challenge in allergic patients.
Patients with negative challenge had IgE levels between 0.35 and 6.41 kU/l, those with mild and moderate reaction had IgE levels of 0.35-14.90 and patients with severe reactions had IgE of 1.18-11.00.
A cut-off level of 8.20 kU/l had a 90% probability of clinical reactivity.
The authors concluded that there was a correlation between IgE titres and the severity of clinical reaction. IgE titres may help determine which patients are at risk of a reaction to eggs.
We already know that higher levels of IgE are associated with more severe asthma (the cut-off level is 100 IU/mL). IgE level is inversely correlated with baseline lung function and asthma severity.
Eight top allergens account for 90 percent of all food allergies. See more Allergy and Immunology mind maps here.
In 2008, the Advisory Committee on Immunization Practices recommended that all children get flu shots except infants younger than 6 months and those with serious egg allergies.
References:
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.
Association between IgE levels and asthma severity among African American, Mexican, and Puerto Rican patients with asthma. Mariam Naqvi at al. JACI, Volume 120, Issue 1, Pages 137-143 (July 2007).
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Updated: 02/27/2008