Epidemiology, outcomes, and disproportionate burden of food-dependent exercise-induced anaphylaxis from the Hong Kong Multidisciplinary Anaphylaxis Management Initiative (HK-MAMI)

BACKGROUND: Anaphylaxis is a life-threatening allergic reaction that poses a considerable burden on populations across all ethnicities and age groups. The Hong Kong Multidisciplinary Anaphylaxis Management Initiative (HK-MAMI) was established to streamline the assessment of patients with anaphylaxis via a multidisciplinary and protocol-driven approach. OBJECTIVE: This prospective study aims to define the etiology, clinical manifestations, and treatment of patients with anaphylaxis in Hong Kong. METHODS: Prospective clinical data from allergologic investigations from patients who completed evaluation by the HK-MAMI pathway between January 2017 and August 2022 were analyzed. RESULTS: Of the 161 patients referred via the HK-MAMI, 131 (81.4%) met the diagnostic criteria for anaphylaxis. The median delay in diagnosis was 2 years (range 0-30 years). The majority of anaphylaxis cases were attributed to food-dependent exercise-induced anaphylaxis (FDEIA), especially wheat-dependent exercise-induced anaphylaxis. In acute management settings, paired tryptase samples were taken in only around one-third of anaphylaxis cases, with 82.5% of the samples demonstrating significant elevation. There was a general underprescription of adrenaline autoinjectors, especially for food-related anaphylaxis. Patients with FDEIA had later ages of onset and diagnosis, and they presented with more cardiovascular manifestations. Skin prick tests and specific IgE level tests were able to diagnose 95% of FDEIA cases. CONCLUSION: Our study highlights the significant burden of FDEIA, and especially WDEIA, in Hong Kong, its association with severe presentations, and difficulties encountered in emergency or primary care settings. We advocate appropriate adrenaline use during acute-care management and discharge plans, as well as taking serum mast cell tryptase samples during acute episodes. Interdisciplinary collaboration remains crucial to upholding proper and optimized care for patients with anaphylaxis in Hong Kong.