Ara H2 [HRP]

The diagnostic accuracy of skin prick test (SPT) and specific IgE (sIgE) to peanut extract in diagnosing peanut allergy is suboptimal. Recent studies have evaluated sIgE to peanut components as a possible new diagnostic tool. The aim of our review was to systematically search the literature to assess the diagnostic value of sIgE to peanut components in diagnosing peanut allergy. A literature search was performed in PubMed, Embase and the Cochrane Library. Results were subsequently screened for in- and exclusion criteria. The quality of eligible studies was assessed using a standardized quality assessment tool (QUADAS-2). Data on sensitivity, specificity, and positive and negative likelihood ratios were extracted or calculated for a descriptive analysis. Twenty-two studies were eligible, of which 21 studies in paediatric populations. Most studies reported on sIgE to peanut extract (15) and sIgE to Ara h 2 (12), followed by SPT (9) and sIgE to Ara h 1 (7). All studies were at risk of bias or caused applicability concerns on at least one item of the quality assessment tool. The best combination of diagnostic accuracy measures of all diagnostic tests was found for sIgE to Ara h 2. This finding was independent of geographical location. Compared to SPT and sIgE to peanut extract, sIgE to Ara h 2 was mainly superior in diagnosing peanut allergy in case of a positive test result. Worst diagnostic accuracy measures were found in general for sIgE to Ara h 8 and sIgE to Ara h 9. sIgE to Ara h 2 showed the best diagnostic accuracy of all diagnostic tests to diagnose peanut allergy. Compared to the currently used SPT and sIgE to peanut extract, sIgE to Ara h 2 was superior in diagnosing peanut allergy and should therefore replace these tests in daily clinical practice, especially in children.

Breastfeeding is currently recommended as the optimal source of nutrition to infants. However, there are several studies that have shown clinical IgE- and non-IgE-mediated reactions to foods in exclusively breastfeeding infants, specifically to cow's milk, egg, peanut, and fish. Literature suggests that antigenic food proteins present in human milk can be found in substantial enough amounts to elicit clinical reactions in some, already-sensitized infants, including anaphylaxis, eczema exacerbation, and non-IgE-mediated gastrointestinal food-allergic syndromes. Diagnosis of food allergy in a breastfed infant and identification of the trigger foods in the mother's diet can be especially challenging in infants with delayed symptoms, such as eczema and gastrointestinal symptoms. Management is further complicated in infants with atopic dermatitis, who have increased caloric needs and therefore in whom nutrition is an extremely important factor for growth and development. One needs to balance possible benefits with risks of further food sensitization through the skin when foods are eliminated from their diets. We review here the literature on clinical presentation and evidence for food allergy in exclusively breastfed infants, including the presence of food antigens in human milk. Incorporating clinical experience and the available data, which largely come from case reports and small, nonrandomized studies performed in referral centers with several limitations, we propose a novel algorithm to diagnosis and management, with emphasis on nutritional considerations. Published by Elsevier Inc. on behalf of the American Academy of Allergy, Asthma & Immunology