Course of mixed connective tissue disease in children.

Mixed connective tissue disease (MCTD) was first reported 25 years ago. This report provides an assessment of the course of juvenile (J) MCTD in 224 patients available in the literature until 1996, including our own 33 patients. Most patients improved and remissions were observed in 3-5% (up to 27%). Among the long-term problems, a loss in joint function was seen in up to 29% of the cases, renal involvement in up to 47%, restrictive lung disease in up to 54% and gastrointestinal manifestations consisting of oesophageal dysmotility in up to 29%. Cerebral involvement was rare but severe. Cardiovascular problems observed include cardiomyopathy, myopericarditis and pulmonary hypertension. Among other long-term problems were Raynaud's phenomenon and scleroderma-like skin changes in up to 86% of the patients. Seventeen of the 224 patients had died (7.6%) because of sepsis or infection (7), cerebral complications (3), heart failure (2), pulmonary hypertension (2), renal failure (2) or gastrointestinal bleeding (1). The mortality rate of JMCTD seems to be in the same range as that of juvenile systemic lupus erythematosus, dermatomyositis and scleroderma. When compared with the other connective tissue diseases, however, mainly minor long-term problems are seen in the surviving patients.