The study’s goals were to characterise diagnostic criteria used in children with coeliac disease (CD) and selective IgA deficiency; to see if the 2012 ESPGHAN criteria caused any modifications; and to assess the development of serological markers. A multicenter, retrospective, descriptive analysis of a cohort of children under the age of 15 with CD and selective IgA deficiency was conducted. At the time of diagnosis and follow-up, demographic, clinical, genetic, histological, and IgG-based antibodies were gathered. Eighty-six youngsters were enrolled in the study, with 60 being diagnosed following the guidance. G1 and G2 groups were created, with or without diagnostic biopsies. In G1, 87.3 percent were symptomatic, 87.3 percent had HLA DQ2/DQ8 typing, all were IgG serology positive, and all exhibited villous atrophy. Follow-up data were available for 58 children, 34 of whom had been on a gluten-free diet for two years. Despite strong dietary adherence and clinical remission, 52 percent of patients remained ATG IgG-positive. Concerning G2, all were diagnosed after 2012, had typical symptoms, were HLA DQ2/DQ8 positive, and had ATG IgG 10 ULN. In addition, 14 people tested positive for EMA IgG.

Children without a diagnostic biopsy in our cohort of children with selective IgA deficiency and CD imply that IgG serology was deemed the equal of IgA isotype, even though this is not addressed in the aforementioned guidelines. The IgG serology utilised for diagnosis showed a high degree of heterogeneity. After two years on a gluten-free diet, half of the youngsters still had a positive serology.