[Subgroups of connective tissue disease].

The present trend is to break down collagen diseases into subsets on the basis of specific clinical signs, genetic data and, above all, serological data, notably the presence or absence of particular antinuclear antibodies. Studies of correlations between clinical symptoms and antinuclear antibodies have yielded precise results with regard to scleroderma, mixed collagenosis and, to a lesser extent, dermatomyositis. In contrast, discordant results have been obtained in systemic lupus erythematosus and dry Sjögren's syndrome, owing to the presence of multiple antibodies in many cases, to differences in the selection of patients and the method used, and to the small number of cases in the subsets investigated.