Food allergy in Sri Lanka - A comparative study

Area of Science:

• Immunology
• Allergy and Immunology
• Clinical Medicine

Background:

• IgE-mediated food allergy (FA) is rising globally, with cow's milk (CM) and hen's egg being common culprits in Western countries.
• Local dietary patterns influence specific food allergies, yet data from South Asia, including Sri Lanka, remains limited.
• This study investigates immediate hypersensitivity triggers in Sri Lanka and compares findings with Asian and Western populations.

Purpose of the Study:

• To identify common food allergens causing immediate hypersensitivity reactions in Sri Lanka.
• To compare the prevalence and characteristics of food allergies in Sri Lanka with those in Asia and Western countries.
• To analyze the onset and associations of specific food allergies, including cow's milk, red meat, and alpha-gal.

Main Methods:

• Retrospective review of 346 patients diagnosed with food allergy at an Immunology clinic from 2010 to January 2022.
• Diagnosis confirmation through standard guidelines, including specific IgE testing (in vitro) and skin prick tests.
• Prick-to-prick testing utilized for fruits and vegetables lacking commercial extracts.

Main Results:

• Cow's milk allergy (CMA) was most frequent (31.2%), followed by red meat allergy (27.7%) and food-dependent exercise-induced anaphylaxis (FDEIA) (17.9%).
• Red meat allergy predominantly affected adults, while CMA onset was mainly in childhood, though adult-onset CMA was observed, sometimes preceded by red meat allergy.
• Anaphylaxis occurred in 213 patients, with FDEIA, red meat allergy, and CMA being common causes. Peanut and fruit allergies were rare.

Conclusions:

• Cow's milk allergy is the primary food allergy in Sri Lankan children, contrasting with rare egg allergies. Primary red meat allergy is the second most common, linked to bovine-product vaccine reactions.
• Red meat allergy may contribute to late-onset cow's milk allergy.
• Findings highlight unique patterns of food allergy in Sri Lanka, differing from Western prevalence, with implications for clinical management and vaccine considerations.