Exploring food-specific IgG responses in pediatric allergic disorders: A retrospective cross-sectional study

Background: The role of immunoglobulin G (IgG) responses to food as potential triggering factors in allergic disorders continues to be debatable, and is not endorsed by most allergy societies. Objective: To explore the prevalence of specific IgG immune responses to common foods in pediatric allergic disorders and any potential relationship between them. Methods: A retrospective study was conducted on children and adolescents diagnosed with allergic disorders at the Ekthar Clinic in Jeddah City. Food-specific IgG (FS-IgG) antibody test results were collected from their medical records. Results: Seventy-five children with a mean age of 8.5 years (SD = 5.3) were included. The overall allergic diagnosis determined atopic dermatitis as the most common (57.3%, 43 participants), followed by food allergy and allergic rhinitis (each 40%, 30 participants), and bronchial asthma (29.3%, 22 participants). Food-specific IgG levels were elevated in all participants. The foods with the highest levels of FS-IgG were dairy products (88%: cow’s milk [86.6%], sour milk [81.3%], sheep’s milk [74.7%], cheese [72%], and goat’s milk [70.7%]), followed by gluten-containing products (81.3%: wheat [70.7%], gluten [69.3%], and spelt [66.6%]), and eggs (66.6%). Significant correlations (P < 0.05) were found between atopic dermatitis and several foods; chronic urticaria and chicken and lamb; asthma and ocean perch; allergic rhinitis and rennet cheese; and allergic conjunctivitis and potato, pollock, and lamb. Conclusion: Among pediatric allergic disorders, dairy, gluten, and eggs were the most detected foods in FS-IgG tests, with some notable correlations with other foods. FS-IgG testing may help identify potential triggers in refractory allergic disorders.