Clinical and atopic features of patients with wheat allergy dependent on augmentation factors (WALDA) presenting with urticaria: a monocentric study

<b>Background.</b> Clinical and laboratory features of wheat allergy dependent on augmentation factor (WALDA) are scarcely characterised as compared to wheat anaphylaxis dependent on augmentation factor (WANDA). In this study we assessed the pattern of comorbid atopic and gastrointestinal diseases and the sensitisation profile in patients with WALDA presenting with intermittent urticaria. <b>Methods</b>. We retrospectively assessed all patients with WALDA-urticaria in a tertiary referral center, with a combined gastrointestinal- allergy unit. WALDA diagnosis was based upon recognised clinical/serological criteria, Clinical, atopic features, allergy tests and gastrointestinal comorbidities were compared to a cohort of O5G negative patients sensitised/allergic to wheat and one of patients allergic to shrimp. <b>Results</b>. Overall, we recruited 11 patients with WALDA presenting with intermittent urticaria (median age 44 years, IQR 29-58, F:M ratio 1.7:1). Atopy was a frequent finding among patients (8/11, 72.7%), with food allergy (6/11, 54.5%) followed by respiratory allergies (5/11, 45.5%). Shrimp sensitisation was present in 8/11 patients (72.7%); half of them were also clinically reactive to shrimp. Irritable bowel syndrome (IBS) was present in 4/11 patients (36.3%). The prevalence of shrimp sensitization was 15.3%, (p=0.01), in a group (n=13) of O5G negative patients with wheat sensitisation/allergy (median age 31 years, IQR 27.7-52.0, F:M ratio 0.4:1), while IBS prevalence was 9% (p=0.12). In the group of patients with shrimp allergy (n=13) with or without allergic rhinitis, the prevalence of O5G positivity was 0% and that of IBS 7.7%. <b>Conclusions.</b> Patients with WALDA-urticaria seems to present specific demographic features (female sex) and atopic (shrimp sensitisation/allergy).