Objective: Celiac disease (CD) is a systemic inflammatory and multifactorial disease caused by intolerance to gluten. Genetic and environmental factors play a role in its development. The most important role in genetic factors is played by the HLADQ2.5 heterodimer formed by the HLA-DQB1*0201 and HLADQA1* 0501 alleles and the HLA-DQ8 heterodimer formed by the HLA-DQB1*0302 and HLA-DQA1*03 alleles.
Our study aimed to determine the distribution of celiac disease susceptibility alleles and the diagnosis rate of celiac disease, in pediatric patients who underwent a genetic predisposition panel at Kırıkkale University Faculty of Medicine Hospital between January 1, 2018, and December 31, 2023. and also the distribution of HLA-DQ2/DQ8 in patients diagnosed with CD during this period.
Material and Methods: Our study included 161 pediatric patients (71 male/90 female) In addition, genetic results were provided for 5 pediatric patients who were diagnosed with CD during the study period but were tested before the study process.Results: Among the pediatric patients who underwent CD panel testing, genetic susceptibility was detected in 139 (86.34%) patients; no susceptibility allele was detected in 22 (13.66%) patients.
When the CD diagnosis was evaluated based on the genotypes of patients with detected susceptibility, 16 out of 62 patients (25.8%) with only HLA-DQ2 positivity, 2 out of 22 patients (9.09%) with only HLA-DQ8 positivity, 1 out of 7 patients (14.3%) with both HLA-DQ2 and HLA-DQ8 positivity, 1 out of 2 patients (50%) with HLA-DQ2 and HLADQB1* 0302 positivity, a patient with HLA-DQ2 and HLADQB1* 03 positivity (%100) and 2 out of 6 patients (33.3%) with HLA-DQ8 and HLA-DQA1*05 positivity received a diagnosis of CD.
When the CD susceptibilities of the 161 patients were evaluated, 23 out of 103 patients (22.3%) with HLA-DQ2 and/or HLA-DQ8 positivity, and one patient with only HLA-DQA1*05 positivity and one patient with only HLADQA1* 03 positivity, in total 25 patients were diagnosed with CD. Conclusion: : Of 161 patients, 25 (15.53%) were diagnosed with CD, with 93.3% being HLA-DQ2/DQ8 positive.
Results confirm these alleles are a necessary predisposition, but their primary clinical utility is their high negative predictive value for disease exclusion.