ABSTRACT
BACKGROUND: There has been limited data regarding the incidence of anaphylaxis in Asia. We aim to describe patterns in patient characteristics, triggers and clinical presentation of childhood anaphylaxis in Singapore. METHODS: This was a retrospective review of emergency electronic medical records of children with anaphylaxis. Patients with the allergy-related diagnoses of anaphylaxis, angioedema, allergy and urticaria based on ICD-9 codes were screened. Cases fulfilling the World Allergy Organization criteria for anaphylaxis were included. RESULTS: A total of 1188 cases of anaphylaxis were identified with a median age of 6.3 years. Extrapolating data from the study sites, from 2015 to 2022, the incidence rate of childhood anaphylaxis emergency visits in Singapore doubled from 18.9 to 38.8 per 100,000 person-years, with an incidence rate ratio (IRR) of 2.06 (95% confidence interval [CI] 1.70-2.49). In 2022, the incidence rate of food anaphylaxis was 30.1 per 100,000 person-years, IRR 2.39 (95% CI 1.90-3.01) and drug anaphylaxis was 4.6 per 100,000 person-years, IRR 1.89 (95% CI 1.11-3.25). The incidence rate in children aged 0-4 years quadrupled during the study period. Common triggers were egg (10.4%), peanut (9.3%), tree nut (8.8%), milk (8%), shellfish (7.8%) and non-steroidal anti-inflammatory drug (4.4%). The majority (88.6%) of patients were treated with intramuscular adrenaline. Total number of allergy-related visits did not increase over time between 2015 and 2019. Rates of severe anaphylaxis, namely anaphylactic shock and admission to high-dependency and intensive care, did not increase over time, with a mean incidence of 1.6, IRR 0.85 (95% CI 0.40-1.83) and 0.7, IRR 1.77 (95% CI 0.54-5.76) per 100,000 person-years, respectively. CONCLUSION: While the number of emergency visits due to childhood anaphylaxis has increased, the number of cases of allergy-related visits, anaphylactic shock and anaphylaxis requiring high-dependency and intensive care did not rise.
ABSTRACT
Background: The rising prevalence of food allergy reported in the United States, UK, and Australia may be attributable to the rise in peanut allergy prevalence. The food allergy prevalence in other parts of the world such as Asia is, however, less well documented. Objective: This study aimed to evaluate the prevalence of cow's milk, egg, and peanut allergies in a general population of Singaporean children below 30 months of age. Methods: A total of 4,115 children from the general population who attended well-baby visits between 2011 and 2015 completed standardized questionnaires to elicit a convincing history of food allergy to estimate the population prevalence of food allergies. Results: The prevalence of a convincing history of cow's milk allergy was 0.51% (95% confidence interval [CI], 0.3-0.7), hen's egg allergy 1.43% (95% CI, 1.1-1.8), and peanut allergy 0.27% (95% CI, 0.12-0.42). Of the 15 of 59 children with a convincing history of hen's egg allergy who consented, 12 (80%) had corroborative positive skin prick tests. Conclusion: The prevalence of food allergy, in particular peanut allergy, in children below 2 years of age is lower in this South East Asian population than reported in Western cohorts. Further research should focus on deciphering differential risk factors for food allergy across different geographical locations.
ABSTRACT
Introduction: Short chain fatty acids (SCFAs) are the main intestinal intermediate and end products of metabolism of dietary fibers/polyphenols by the gut microbiota. The aim of this study was to evaluate the biological implication of stool SCFA profiles determined in the first year of life on the clinical presentation of allergic outcomes in childhood. Methods: From the Growing Up in Singapore Toward healthy Outcomes (GUSTO) cohort, a sub-cohort of 75 participants was recruited. Scheduled questionnaire data was collected for cumulative prevalence of physician-diagnosed eczema, wheezing with the use of nebuliser, and allergen sensitization till the age of 8 years. Stool samples collected at week 3 and months 3, 6 and 12 were quantitated for 9 SCFAs using LC/MS/MS. SCFA data were grouped into lower (below the 25th) and higher (above the 75th percentiles) categories. Generalized Linear Mixed Models was employed to analyse longitudinal association between SCFAs and atopy-related outcomes. Results: Children with lower stool butyric acid levels (≤25th percentile) over the first 3 time points had higher odds ratio (OR) for wheezing (adjOR = 14.6), eczema (adjOR = 13.2), food sensitization (adjOR = 12.3) and combined outcomes of both wheezing and eczema (adjOR = 22.6) till age 8 years, compared to those with higher levels (≥75 percentile). Additionally, lower longitudinal levels of propionic acid (≤25th percentile) over 4 time points in first year of life was associated with recurrent wheezing (≥2 episodes) till 8 years (adjOR = 7.4) (adj p < 0.05). Conclusion: Our results suggest that relatively low levels of gut SCFAs in early life are associated with increased susceptibility to atopic-related outcomes in childhood.
