METHODS: Patients with confirmed fish/shellfish allergy were recruited through the Allergy Clinics at the Montreal and British Columbia Children’s Hospitals and from Food allergy Canada and followed. Confirmed cases had a convincing history of fish/shellfish allergy, positive skin tests and/or a positive oral challenge. Resolution was defined if the treating physician diagnosed tolerance and/or the culprit seafood was tolerated. Descriptive statistics and assessment of resolution was conducted using SAS 9.4.
RESULTS: Our cohort was recruited between 2011-2016 and included 96 cases. Thirty-seven with fish allergy, 25 with shellfish allergy, and 1 with both responded to the follow up questionnaire (49 children and 14 adults). Sociodemographic and clinical characteristics were similar between responders and non-responders except for ethnicity (responders: 62.1% white, non-responders: 43.8% white). Among the fish and shellfish cohorts there were 42.1% and 46.2% females, with mean age at diagnosis of 3.4 and 8.8 years respectively. Asthma and eczema were reported in 34.2% and 68.4% of cases with fish allergy and 46.2% and 50% of cases with shellfish allergy. The most common culprits were salmon (18.4%) and shrimp (50%) respectively. There was 1 case of confirmed fish allergy resolution and 1 case of confirmed shellfish resolution followed over 173.9 and 124.7 person-years respectively. The resolution rate was 0.6% (95% CI 0.02, 3.2) per person year for fish and 0.8% (95% CI 0.02, 4.5) per person year for shellfish.
CONCLUSIONS: Our findings indicate low rate of resolution for seafood allergy.