1 - Serviço de Imunoalergologia, Centro Hospitalar Universitário de Lisboa Central
- EAACI 2022
Background. Wheat-related allergic disorders are more prevalent in Asian countries than in Europe. They have a wide spectrum, from food allergy (FA) (IgE, non-IgE, or mixed mechanisms) to respiratory allergy (RA). They can lead to anaphylaxis, can be triggered by physical exercise, and can have a significant social impact.
Method. To better understand wheat FA (WFA), a retrospective analysis of the last 10 years clinical files of patients with sensitization to wheat (specific IgE- sIgE >0,35KUA/L) was performed concerning symptoms, first evaluation (FE) age, tolerance acquisition (TA), TA age, sIgE evolution, presence of multiple FA (MFA), allergy to other cereals or RA.
Results. From 172 patients, 16 were excluded (lack of data), remaining 156. 44 (28%) had clinical WFA. 17/44 (39%) developed symptoms suggestive of mixed mechanisms: worsening atopic dermatitis (10); gastrointestinal symptoms (7). Median age at diagnosis (P25-75) was 1 (0,7-2,0) years old (yo). 27/44 patients (61%) had symptoms that suggest IgE mediated WFA: 14/27 (52%) only had mucocutaneous symptoms – and 13/27 (48%) had anaphylaxis; 19/27 (70%) had MFA; 7/27 (26%) had allergy to other cereals; 17/27 (63%) had RA not related with FA. Median age at diagnosis (P25-75) was 1 (0,7-12,0) yo. During the follow-up period, 6/27 patients withdraw, 13/21 (62%) had persistent FA (pFA) to wheat, and 8/21 (38%) acquired tolerance (AT) at a median age (P25-75) of 2 (2-5,25) yo. There was no significant difference between median sIgE at FE of pFA group – 54,1 (12,4-95,1) KUA/L and AT group – 19,9 (5,6-49,7) KUA/L (U=31; p=0,140). On the TA group, the median reduction of sIgE between FE and TA was 7,6 (0,8-28,2) KUA/L; on the pFA group there was a median increase of 0,6 (-8,4-19,4) KUA/L between FE and last evaluation.
Conclusion. Half of patients with WFA had anaphylaxis, despite most wheat sensitizations had no clinical expression (72%). This emphasizes that clinical evaluation performed by a trained physician is crucial to avoid not just unnecessary and potentially harmful diet restrictions, but also potentially fatal reactions. Most WFA started in infancy, which raises awareness about the need for close monitoring of baby weaning. sIgE reduces in TA group and increases on pFA group, suggesting sIgE monitoring could be useful to predict tolerance acquisition.
Palavras Chave: food allergy, wheat