[Study of the fibrin degradation products in the synovial fluid of rheumatological diseases (author's transl)].

FDP were studied in the synovial fluid of 23 patients with various rheumatological diseases. The levels, measured by the passive hemagglutination inhibition technique (Merskey technique), showed variable values, but were always found to be present. On half the cases a number of these molecules could be eliminated by a high dose of thrombin. Using three immune sera (anti-fibrinogen, anti-D, anti-E), immunoelectrophoresis revealed in half the cases one central nonmigrating arc and another with cathodic migration. This differs from results using FDP obtained by the digestion of fibrinogen by plasmin, but is, however, analagous with those obtained in vitro by the action of proteases of leukocyte origin. These results suggest that the intense fibrinogen catabolism within the pathological joints results from the action of proteolytic enzymes other than plasmin.