Clinical predictors and outcomes of oral food challenges illustrate differences among individual tree nuts

Abstract

RATIONALE: Walnut is a relevant allergenic food in paediatric population. An accurate diagnosis is essential. The aim of this study was to assess the diagnostic capacity of natural and three commercial walnut extracts to perform skin prick tests (SPT). METHODS: Fifty-one atopic children were included in the study; 39 with a clinical history of walnut allergy and positive specific IgE values to walnut (> _ 0.35 KU/L) and 12 atopic controls tolerating walnut. SPT whit three commercial walnut extracts (ALKÒ, LetiÒ, RoxallÒ) as well as prick-prick test (PPT) with natural walnut were performed. Wheals > _3 mm were considered positive. The sensitivity and specificity for SPTs with commercial extracts and natural walnut, as well as wheal sizes (WS), were analyzed. RESULTS: SPTs with ALKÒ, RoxallÒ and LetiÒ walnut extracts as well as natural walnut, showed high sensitivity (100; 100; 97.44; 100) but moderate to low specificity (75; 41.66; 41.66; 58,33) values with no differences between them. In walnut allergic patients, the median WS with Roxall'sÒ walnut extract (9.5mm) was significantly larger than Leti'sÒ (7.5mm; p <0.001) and ALK'sÒ (7.5mm; p <0.001) but similar to those of the PPT (9.5mm; p 5 0.566), while ALK'sÒ and Leti'sÒ WSs were significantly smaller compared to those of the PPT (p5 0,003; p<0,001). CONCLUSIONS: Commercial walnut extracts from ALKÒ, RoxallÒ and LetiÒ have a similar diagnostic accuracy. However, in walnut allergic patients, the WS of the SPT with Roxall's walnut extract is significantly larger than those performed with ALK's and Leti's extracts and similar to the PPT.

Recent advances in the diagnosis and management of tree nut and seed allergy

“…In those TN-sensitized without lifetime exposure to TN, 91% of 65 OFCs were successful, whereas 76% of 67 OFCs were tolerated to another TN in those with a history of TN allergy. OFCs to almonds (94–100%) and hazelnut (83–88%) were the most commonly tolerated, suggesting that these could be challenged more aggressively [62,63 ▪ ,64].…”

Advances in allergen‐specific immune cell measurements for improved detection of allergic sensitization and immunotherapy responses

“…8). Even though serum IgE correlates well with responses to allergen challenges, 9 this has its limitations: Serum‐specific IgE can be used to distinguish sensitized from non‐sensitized individuals, but it is a marker that is only present after the development of a pathogenic response and can provide little if any information on the disease cause/origin; Serum‐specific IgE persists following clinically successful treatment with AIT. Thus, it cannot be used to obtain understanding of how this treatment modifies the pathogenic response or to monitor clinical response. …”