[The Sharp syndrome ("mixed connective tissue disease")].

A new and distinct rheumatic disease with features of systemic lupus erythematosus (SLE), progressive systemic sclerosis and polymyositis is described. Typical symptons are Raynaud's syndrome, swollen hands and fingers, polyarthritis or polyarthralgia and myositis. Other symptoms are less common and include skin lesions, decreased pulmonary diffusing capacity, diminished esophageal motility, lymphadenopathy, and polyserositis. The diagnosis of mixed connective tissue disease (MCTD) can be established by demonstration of a high titer of antinuclear antibodies and antibodies against extractable nuclear antigen (anti-ENA). Both antibodies are directed against ribonuclease-sensitive antigen substrate, which permits differentiation of patients with MCTD from those with other rheumatic diseases. A relatively favourable prognosis and a good response to corticoid medication are further characteristics of this disease. Three personally observed patients with MCTD are described.