[The Sharp syndrome (mixed connective tissue diseases) (author's transl)].

Sharp and coworkers (69) recently described a group of patients with over-lapping syndromes of lupus erythematosus, polymyositis and progressive systemic sclerosis. Since all these patients showed high titers of an antibody against RNP (ribonucleoproutein), a saline extractable constituent of nuclei, the disease was supposed to be a unique entity within the spectrum of collagen diseases (mixed connective tissue disease, overlapping syndrome). The nosological entity, however, remains to be further established since RNP-antibodies not infrequently occur in other collagenoses (LE, RA) and transition of MCTD in LE have been reported. The clinical syndromes and the serological features of MCTD are described.