Ara h 2–specific IgE is superior to whole peanut extract–based serology or skin prick test for diagnosis of peanut allergy in infancy

Current insights: a systemic review of therapeutic options for peanut allergy

“…Among PPs, IgE antibodies to Ara h2, are most often associated with severe allergic reactions. Ara h2 is an important predictor of clinical PA and recent studies have reported that Ara h2-IgE is superior to peanut SPT or sIgE for diagnosis of PA with the best profile of high specificity, high sensitivity and lowest risk of a false-positive diagnosis of PA [36–41,42 ▪ ]. Recently it has been suggested that using s-IgE to Ara h2 as a diagnostic method to differentiate peanut tolerance from PA and reduce the need for OFCs [43].…”

“…Recently it has been suggested that using s-IgE to Ara h2 as a diagnostic method to differentiate peanut tolerance from PA and reduce the need for OFCs [43]. Although peanut sIgE is more diagnostically sensitive, its low specificity indicates that most patients that test positive in a screening population do not actually have PA [42 ▪ ]. Screening with Ara h 2-sIgE only, instead of peanut s-IgE is more cost-effective, reduces the number of false-positive cases, and reduces the requirement for OFC or referral to an allergic clinic enabling nonspecialists to screen, therefore reducing the time taken to diagnose PA [37,42 ▪ ,44].…”

Reply

“…We thank Greenhawt et al 1 for their interest in our recent article. 2 The authors speculate that in other populations specificity of Ara h2-specific IgE may be lower and discuss economic considerations regarding screening for peanut allergy before peanut introduction. 1 With regard to the improved specificity that we found in this study compared with other studies of peanut allergy diagnostics, we believe that this is mostly due to the study design rather than demographic or geographic considerations.…”

Diagnosis of Peanut Allergy in Preschool Children: The Impact of Skin Testing With a Novel Composition of Peanuts

“…The diagnosis of peanut allergy in the clinical setting is based on a suggestive medical history upon exposure to a relevant food in conjunction with evidence of IgE-mediated sensitization via a skin prick test or peanut-specific IgE (4)(5)(6). Although 95% confidence levels for both skin tests and peanut-specific IgE have been published (7), and component resolved diagnostics (CRD) have been proposed to improve diagnostic accuracy (8)(9)(10), medically supervised oral food challenges (OFCs) are still the "gold standard" (6) for diagnosis.…”