Joint involvement in progressive systemic sclerosis (scleroderma): a light and electron microscopic study of synovial membrane and fluid.

Abstract

In six patients with progressive systemic sclerosis the synovial membrane was characterized by superficial deposition of fibrin, mild chronic inflammation with very little proliferation of lining cells, prominence of what appears to be immature connective tissue, and previously unrecognized obliterative microvascular disease. Leukocyte counts of synovial fluid were generally less than 1,000 cells per cu. mm., predominantly mononuclear cells. These typical findings taken together should suggest the diagnosis of scleroderma. The prominent microvascular lesions of still unknown mechanism suggest the small vessels as a likely site for the initial injury.