Immediate food hypersensitivity among adults attending a clinical immunology/allergy centre in Singapore

Abstract

Introduction: The patient characteristics, clinical features and causative foods in 74 consecutive adult patients with immediate food hypersensitivity were studied.

Methods: A retrospective review of 74 consecutive adults who presented during the study period from July 1, 1994 to April 30, 2002 was performed.

Results: There were 35 male and 39 female patients, with a mean age of 36.3 +/- 10.9 (range, 19-66) years. The most common causative foods were seafood crustaceans, molluscs and bird's nest. Prawn and crab were the most commonly implicated crustacean, and limpet the commonest culprit mollusc. The main symptoms were periorbital angioedema (64.9 percent), dyspnoea/wheezing (44.6 percent) and urticaria (44.6 percent). 66 percent of the patients developed anaphylaxis. 34 (45.9 percent) had concomitant allergic rhinoconjunctivitis, asthma, eczema or combinations of these atopic diseases. Only six (8.1 percent) patients had a family history of food allergy. Skin prick tests (SPT) to commercially-prepared food allergens were positive in 22 of 36 patients (61.1 percent) tested. SPT to the fresh, cooked or canned food products were positive in 11 of 20 (55 percent) cases where the food allergen was not commercially available. Open food challenges were required for diagnosis in two patients who had negative SPT.

Conclusion: The most common food allergens in our patients were seafood crustaceans, molluscs and bird's nest. More than half of the patients had concomitant allergic rhinitis, asthma and/or eczema. The pattern of food allergy in Singapore differs from Caucasian populations, likely to be because of different regional dietary patterns and methods of food preparation.