ABSTRACT
The group of psoriatic arthritis (PSA) is heterogeneous and probably includes conditions with different genetic backgrounds. Synovial joint membranes were obtained by synovectomy in bloodless fields by open surgery from 15 patients with PSA. Synovial membranes from 13 joints in ten patients with PSA and from 6 joints in five patients with seropositive rheumatoid arthritis (RA) were examined for vasculitis and perivasculitis. Synovial joint membranes from 15 patients with PSA and 5 patients with meniscal tears were investigated for deposition of fibrin. Staining with the anti-T-lymphocyte antiserum presented a distinct rimlike membrane fluorescence of the majority of the infiltrating cells in the synovial membranes. Psoriatic arthritis — In 14/15 patients intracellular depositions of immunoglobulins were found in the cytoplasm of plasma cells. In synovial membranes in PSA, large accumulations of infiltrating mononuclear cells are found, as in seropositive RA. These cells belong mainly to the T-cell line, together with B-cells and plasma cells.
