[The morphogenesis of chronic synovitis in rheumatoid arthritis].

The synovial sheath obtained in synovectomy in 35 patients with rheumatic- and rheumatic-visceral forms of rheumatoid arthritis was studied histochemically and immunomorphologically. At early stages of exacerbation of the pathological process in the synovial tissue there were revealed predominantly catabolic processes: an increased permeability of vessels; mucoid oedema; fibrinoid changes in the subintimal layer. Further development of the disease was characterized by predominance of anabolic processes with proliferation of synoviocytes, subintimal histiocytes, productive vasculites, massive lymphoid-plasmocytic infiltration, diffuse, or in the form of lymphoid follicles. Using the immunofluorescent technique the authors revealed luminescence of the rheumatoid factor and gamma=globulin in plasmatic cells, extracellularly, and more rarely in macrophages. Pronounced immunological changes in the synovial sheath in the active course of rheumatoid arthritis were accompanied by a high level of metabolic processes and an intensive phagocytic reaction in synoviocytes and subintimal histiocytes. In observations with a low activity of rheumatoid arthritis the synovial tissue was characterized by low levels of enzymes of oxidative metabolism and hydrolysis, emptying of the capillary bed, processes of sclerosis, hyalinosis, amyloidosis.