Lack of association between HLA-DRB1 alleles of the major histocompatibility complex and p-ANCA status or clinical characteristics in patients with ulcerative colitis.

INTRODUCTION: An association between different HLA-subtypes and ulcerative colitis has been described in various study populations of different ethnic and geographic background. Moreover, a correlation between HLA-DR2 and ulcerative colitis, in particular p-ANCA-positive ulcerative colitis, was reported. Thus, the present study aimed on the correlation of HLA-DRB1* alleles with the presence of p-ANCA and clinical characteristics in individuals of southern german descent.

PATIENTS AND METHODS: The study population comprised 56 patients with ulcerative colitis and 177 healthy controls. HLA-DRB1* alleles were assessed by use of the dot blot method. Autoanti-bodies were visualized by indirect immunofluorescence on ethanol-fixed neutrophils.

RESULTS: The allele HLA-DRB1*12 was more frequent in patients with ulcerative colitis (p = 0.01). After correction for the number of alleles tested (n = 16) statistical significance was no longer preserved. A weak association between the presence of HLA-DR5 and the detection of p-ANCA in ulcerative colitis was found (p = 0.0375). After correction for the number of comparisons (n = 10) no associations between HLA-DR antigens and the presence of p-ANCA remained. Furthermore, no significant correlations between clinical characteristics of ulcerative colitis and HLA-DR antigens were detected.

DISCUSSION: Genes encoding for HLA-DR antigens are unlikely to have an impact on the heredity and the presence of disease phenotypes of ulcerative colitis in a study population of southern german descent.