Patient sensitization profile and fish species' tolerance in children with IgE-mediated fish allergy

Fish allergy remains a poorly investigated topic despite its potential severity and impact on child well-being. There is a paucity of data on IgE fish allergy in pediatric patients in the Mediterranean region.

52 children with IgE-mediated fish allergy underwent OFCs with different fish species. The adopted OFC protocols were according to PRACTALL Consensus. Nonparametric quantitative variables were compared between two groups using the Mann-Whitney U test, and the data were visualised using box plots. Fisher's exact test was used to assess the significance between dichotomous categorical variables.

A total of 72 OFCs were performed over time; 17/52 patients underwent an OFC for at least two different fish species. 52/58 patients (89.6%) successfully overcame OFCs with fish species other than the trigger one, mostly tuna (19/21; 90.5%), salmon (15/17; 88.2%), and swordfish (6/6 100%), respectively. sIgE for tested fish were positive in 41 out of negative OFCs (41/62; 66.1%) and in 5 out of 10 positive OFCs (5/10; 50%), respectively. Fish-sIgE levels were >10 kUA/L(range 12.3-37.5 KU/Lt). sIgE levels between positive and negative OFCs were not significantly different (Mann-Whitney U test, P = 0.33). Moreover, no significant association between sIgE levels and the OFC outcome (Fisher's exact test, P = 0.18) was observed.

Patients with IgE-mediated fish allergies can safely consume one or more fish species, especially tuna, salmon, and swordfish. Tolerance should be confirmed by an OFC, since the sIgE levels do not predict clinical reactivity.