Mixed connective tissue disease--clinical and radiological aspects of 20 cases.

The clinical and radiological features of 20 cases of mixed connective tissue disease (MCTD), a newly defined disorder, are described. MCTD shares a number of abnormalities with other collagen diseases, notably diffuse systemic sclerosis and systemic lupus erythematosus. However, patients with MCTD have a specific circulating antibody to extractable nuclear antigen (ENA). Most of the cases described exhibited multi-system involvement with radiological changes in the skeleton, chest, and gastro-intestinal tract. Twelve of the 20 cases had an erosive arthritis. This finding has not been previously noted in the radiological literature.