IgE-mediated coconut allergy in tropical Singapore.

Background: Coconut (Cocos nucifera) is a fruit belonging to the Arecaceae plant family. It is not a common allergen and literature on it is limited. Currently, there is a lack of data on coconut allergy in Asia, despite it being a fruit commonly used as a food ingredient in tropical Southeast Asia.

Objective: In this study, we aimed to describe the demographics, clinical features, and natural history of Singaporean children with IgE-mediated coconut allergy.

Methods: A retrospective review was conducted for children diagnosed with coconut allergy in a tertiary pediatric hospital in Singapore between 2017 and 2022.

Results: The diagnosis of coconut allergy was made in 41 patients based on convincing history of IgE-mediated allergic reaction and a positive test (prick-to-prick test to coconut water, coconut flesh, and/or specific immunoglobulin E). The median age at first reaction was 20 months (range: 6-96 months) with most reacting on first ingestion (80.5%). Majority presented with cutaneous reactions (90.2%). Anaphylaxis occurred in 9.8%, with all involving cutaneous and respiratory systems. Most reacted to coconut milk (34.1%). Majority (82.9%) had another food allergy and a personal history of atopy (90.2%). Median duration of follow-up was 35 months (range: 3-109). Only 1 of the 41 patients reported natural tolerance at 76 months.

Conclusions: Although a relatively uncommon food allergy, coconut allergy is a significant problem as anaphylaxis occurs in 1 in 10 and appears to be a persistent allergy.