Real-World Sensitization and Tolerance Pattern to Seafood in Fish-Allergic Individuals.

BACKGROUND: Seafood is a common cause of food allergy and anaphylaxis, but there are limited published real-world data describing the clinical presentation of fish and shellfish allergies. OBJECTIVE: This study aimed to examine the clinical characteristics, immunological profile, and tolerance pattern to fish, crustaceans, and mollusks in fish-allergic individuals. METHODS: Patients presenting with IgE-mediated fish allergy between 2016 and 2021 were recruited. A comprehensive sensitization profile including specific IgE and skin prick test to various fish and shellfish species and a detailed clinical history including individuals' recent seafood consumption were evaluated. RESULTS: A total of 249 fish-allergic individuals (aged 4.2 ± 5.8 years) were recruited from 6 allergy clinics in Hong Kong, and they had experienced their fish-allergic reaction 2.2 ± 3.4 years before enrollment. Seventy-five subjects (30%) reacted to either grass carp, salmon, grouper, or cod in oral food challenges. We identified an IgE sensitization gradient that corresponded to the level of ß-parvalbumin in fish. In total, 40% of fish-allergic individuals reported tolerance to 1 or more types of fish, more commonly to fish with a lower ß-parvalbumin level such as tuna and salmon, compared with ß-parvalbumin-rich fish such as catfish and grass carp. Despite fish and shellfish cosensitization, 41% of individuals reported tolerance to crustaceans, mollusks, or both, whereas shellfish avoidance occurred in half of the fish-allergic individuals, of whom 33% lacked shellfish sensitization. CONCLUSIONS: Fish allergy commonly presents in early childhood. A considerable proportion of fish-allergic patients are selectively tolerant to certain fish, typically those with lower levels of ß-parvalbumin. There is an unmet need to promote precision medicine for seafood allergies.

Prospective study of disease persistence and lung function trajectories of childhood asthma.

BACKGROUND: A proportion of asthmatic children outgrow their disease by adulthood, but there are limited data on predictors for asthma persistence. This prospective study characterized the trajectory of spirometric indices and identified predictors for the persistence of childhood asthma. METHODS: Chinese asthmatic children aged 6-15 years from pediatric allergy clinic underwent annual visits for ≥5 years and until their adulthood. Pre-bronchodilator spirometry and anti-asthma medications were recorded at baseline and then at least annually. Asthma resolution was defined when patients were free from asthma symptoms and use of anti-asthma drugs for ≥2 years. Logistic regression was used to identify predictors for asthma persistence. Generalized estimating equation was used to analyze longitudinal changes in lung function parameters in relation to asthma persistence. RESULTS: 181 asthmatic children aged [mean (SD)] 10.0 (2.7) years were followed for [mean (SD)] 12.5 (2.8) years. One third of them outgrew asthma during follow-up. Female was 3.36 times more likely to have persistent asthma. Inhaled corticosteroid (ICS) treatment ever and frequent asthma exacerbation (AE) predicted asthma persistence with respective odds ratios of 3.19 (95% confidence interval [CI] 1.44-7.09) and 3.05 (95% CI 1.39-6.68). Persistent asthma was inversely associated with baseline forced expiratory volume in 1-second (FEV1 %) with an odds ratio of 0.96 (95% CI 0.93-1.00). Throughout follow-up, patients with persistent asthma had generally lower forced expiratory indices than those with asthma resolution. Children with persistent asthma experienced poorer lung function growth. CONCLUSIONS: Female, ICS ever, and frequent AE predicted persistent asthma. Patients with persistent asthma had lower forced expiratory indices and poorer lung function growth into adulthood.

Identification of predictors for persistence of immediate-type egg allergy in Chinese children.

BACKGROUND: Egg allergy is one of the most common food allergies in childhood with increasing prevalence in Hong Kong. While ample studies were published on its optimal diagnosis, there was limited data on predictors for the natural history of egg allergy in Asian populations. OBJECTIVE: This study aimed to characterize the clinical course and outcome of children with egg allergy and identify its prognostic factors. METHODS: All Chinese children with immediate-type egg allergy being followed since ≥3 years old in allergy clinic of our university-affiliated teaching hospital were reviewed to determine if they outgrew egg allergy at the latest follow-up. The predictive values of clinical and atopic factors for resolution of egg allergy were analyzed on Kaplan-Meier curves, and factors independently associated with persistent egg allergy was analyzed by logistic regression. RESULTS: Seventy-six patients with median (interquartile range) age 8.9 years (6.3-13.0 years) were recruited. They initially presented with egg-allergic reactions at 1.0 years (0.7-1.7 years). Fifty-four children (71%) were able to tolerate egg at a median of 36 months from initial reaction. Patients with concomitant peanut allergy and those with initial reaction at ≥1 year old were more likely to have persistent egg allergy (p = 0.015 and p = 0.027 respectively). Skin prick test wheal ≥6 mm to egg yolk and egg white individually as well as to both egg yolk and egg white were predictors for egg allergy persistence (respective, p < 0.001, p = 0.001, and p = 0.001 by log-rank tests). Logistic regression showed that initial SPT ≥ 6 mm to egg yolk was the only independent predictor for persistent egg allergy (B = 2.59 ± 0.98, p = 0.008). CONCLUSION: Most Chinese children with immediate-type egg allergy can tolerate egg in long run. SPT wheal size to egg, concomitant peanut allergy and initial presentation after infancy may predict egg allergy persistence.