Patterns of food allergen sensitization and co-sensitization in Jordan: A laboratory-based analysis

Food allergy is an increasing global health concern, yet laboratory-based data on food allergen sensitization in Jordan remain limited.

To estimate the prevalence and burden of sensitization to common food allergens among patients undergoing serum specific IgE (sIgE) testing in Jordan, and to characterize co-sensitization patterns in routine clinical practice.

We retrospectively reviewed patients who underwent a standardized 34-food allergen sIgE panel between 2021 and 2024. Sensitization more frequently associated with clinical symptoms was defined a priori as Class ≥ 2; analyses were repeated at Class ≥ 1 as a sensitivity analysis. Patients were categorized as non-sensitized, monosensitized, oligosensitized (2-4 allergens), or polysensitized (≥ 5). Allergen-specific prevalence was estimated with Wilson 95% confidence intervals, and co-sensitization was explored using correlation matrices and hierarchical clustering.

Among 405 patients (13,770 tests), 28.4% were sensitized to at least one food allergen (n = 115); most had no or a single positive result, whereas 6.7% (n = 27) were polysensitized. Shellfish (8.2%; 95%CI 5.8-11.4), cow's milk (7.4%; 5.2-10.5), and egg white (6.9%; 4.8-9.9) were most prevalent. No significant differences were observed by age or sex after adjustment for multiple comparisons. Co-sensitization analysis identified interpretable clusters, particularly among nuts/seeds, cereals, and selected animal-derived allergens. Similar patterns were observed at Class ≥ 1.

These laboratory-based findings may support diagnostic testing, counseling, and allergy service planning in Jordan.