HLADQ2 and HLADQ8 Alleles Are Associated with Celiac Disease in Children

Background: Celiac disease is the permanent intolerance to dietary gluten, the major protein component of wheat. The role of human leukocyte antigen (HLA) DQ2 heterodimer (DQA1*0501-DQB1*0201) in presenting gluten peptides to effectors T cells in celiac disease (CD) has been well documented. Epidemiological studies of the disease in Iran are not available. This study was aimed to investigate the frequency of HLADQ2 and HLADQ8 in children with celiac disease in Mashhad city. Methods: This case-control study was conducted on 25 celiac patients and 25 matched healthy controls for HLA typing of DQ2/DQ8. CD diagnosis was reached in 25 subjects, according to the revised criteria of the European Society for Pediatric Gastroenterology Hepatology and Nutrition (ESPGHAN) and North American Society for Pediatric Gastroenterology, Hepatology and Nutrition criteria (NASPGHAN). Sensitivity, specificity, and negative and positive predictive values were calculated. Results: Mean age was 134.06±30.48 months in case and control groups, with no statistical difference between the two groups. 48% of cases and controls were male, and 52 % were female. HLA-DQ2/8 was positive with 80% (CI 95%:64-95), sensitivity was 80% (CI 95%:58-92), specificity 48% (CI 95%:28-68), NPV 70.58% (CI 95%:44-88), PPV 61(CI 95%:42.2-76.5) and accuracy was 64%. Conclusion: A positive association was found between HLA DQ2/8 and Iranian celiac disease. As negative and predictive values were high, HLA typing may be considered a beneficial test for diagnosis confirmation.