Banana anaphylaxis in Thailand: case series

BACKGROUND: Banana fruit has been recognized as an important food allergen source. Nowadays banana hypersensitivity had been reported more frequently with various presentations from oral allergy syndrome to anaphylaxis.OBJECTIVE: This study aims to describe the pattern of banana hypersensitivity and the sensitivity of diagnostic test.METHODS: Six patients who experienced banana hypersensitivity were recruited from adult allergy clinic, Ramathibodi Hospital, Mahidol University between 2015–2018. Demographic data, pattern of banana allergy consisted of the onset of reaction, symptoms, severity, cross-reactivity to kiwi, avocado, latex including type and amount of banana were collected. Skin test, serum specific IgE to banana and open-label food challenge test had been applied.RESULTS: All patients experienced multiple episodes of banana anaphylaxis. Regarding the diagnostic investigation, prick-to-prick skin test had higher sensitivity (sensitivity, 100%; 95% confidence interval [CI], 54.07%–100%) than the commercial banana extract (sensitivity, 83.33%; 95% CI, 35.88%–99.58%) and serum specific IgE to banana (sensitivity, 50%; 95% CI, 11.81%–88.19%). The discordance between skin prick test using commercial banana extract and skin test was reported. The cross-reactivity between the species of banana, kiwi, the avocado was documented in all patients. Latex skin prick test and application test were applied with negative results. From the oral food challenge test, a case of banana anaphylaxis patient can tolerate heated banana.CONCLUSION: The various phenotypes of banana hypersensitivity were identified. The prick-to-prick test showed the highest sensitivity for diagnosis of banana allergy. However, component resolved diagnostics might be needed for conclusive diagnosis.

Skin prick test reactivity to aeroallergens in adult allergy clinic in Thailand: a 12-year retrospective study

BACKGROUND: The global prevalence of allergic rhinitis, asthma, and atopic dermatitis has risen significantly over the last 2 decades. Allergic sensitization to aeroallergen is a major risk factor in developing the allergic disease. The prevalence of aeroallergen sensitization varies in different regions and countries. OBJECTIVE: To determine the prevalence of common aeroallergen sensitization and the atopic status among adult patients. METHODS: A cross-sectional, retrospective study. The data were collected from medical records and database of the result of skin prick test of patients who had the allergic symptoms or chronic urticaria in adult allergy clinic, Ramathibodi hospital from January 2004 to December 2015. RESULTS: A total of 1,516 of patients (female, 1,118 [73.7%]) were enrolled. The mean ages of participants were 41.34 (standard deviation, ±16.5) years. Fifty-eight percent (58%) of patients were diagnosed with allergic rhinitis, 19.7%, 3.2%, and 9.2% with asthma, atopic dermatitis, and chronic urticaria respectively. In the chronic urticaria group, 57.4% underwent the positive skin prick test to common aeroallergens. Mites were responsible for the most common inhaled allergen sensitization in this study as 50.1% of Dermatophagoides pteronyssinus, 32% of Dermatophagoides farinae, and 31.5% of house dust. Cockroach was the second most common aeroallergen sensitization as 32.3% followed by grass pollen, Bermuda (21.1%) and timothy (13.6%). The animal dander, cat and dog, occupied 12.9 and 10% respectively. CONCLUSION: Mites were the most common cause of aeroallergen sensitization in all patients followed by cockroach, grass pollen, and animal dander. However, Bermuda sensitization has increased significantly in the last 6 years.