Diagnostic significance of HLA-DQ typing in patients with previous coeliac disease diagnosis based on histology alone.

Background Coeliac disease is strongly associated with human leukocyte antigen (HLA)-DQ2 or DQ8 genotypes. The diagnosis is based on demonstrating crypt-hyperplastic villous atrophy, endomysial or transglutaminase antibodies and correlation of disease activity with gluten intake. Aim To evaluate the clinical utility of HLA-DQ typing, when coeliac disease diagnosis had previously been established solely by histology. Methods HLA-DQ alleles, endomysial and transglutaminase antibodies were investigated and histology slides reviewed in 70 patients diagnosed 2-25 years earlier by small-intestinal biopsy but without measuring endomysial or transglutaminase antibodies. Patients without DQ2 or DQ8 or without unequivocal villous atrophy were followed-up on free diet by using serology and biopsies. Results All 40 endomysial/transglutaminase antibodies positive patients carried DQ2 or DQ8, and 39 of them had severe villous atrophy. Only 56% of patients withou