Oral lichen planus and HLA DR

Oral lichen planus (OLP) is a chronic inflammatory mucocutaneous disease, p redominantly seen in middle-aged female patients. Histopathologically: OLP includes parakeratosis with T-lymphocyte subepithelial infiltration. In eti ology of OLP, chronically liver and billiary diseases, stress-induced hyper tension, inheritance and most commonly carbohydrate metabolism disorders in cluding diabetes mellitus are mentioned. Considering the autoimune nature o f the illness and the role of the HLA DR 3/4 antigens in development of dia betes mellitus we hypothesized that the same antigens could play role in th e development of OLP. We examined 50 unrelated Croatian patients (5 males) from Institute of Oral Pathology, Faculty of Dental Medicine, Zagreb, with clinical and histopathological diagnosis of OLP. They were all tested for H LA DR and compared with 1089 Croatian controls that underwent the tissue st andardization in father-ship cases. OLP patients had blood sugar level cont rolled, and those with HLA DR 3/4 and those with blood sugar level higher t hen 5,6 mmol/l additionally underwent standard oral glucose tolerance test. Carbohydrate metabolism disorder was found in 13 OLP patients (26%) while 10 of them (20%) had diabetes mellitus type I. This finding is 400 times mo re frequent than is appearance of diabetes in healthy controls (0.05%) in C roatia.