A method for assessment of the stage of the inflammatory process activity in the synovial membrane of the joints in rheumatoid arthritis patients

A method has been developed for assessment of the stage of the inflammatory process activity in the synovial membrane of the joints by the amount of absorbed tetracycline preliminarily injected into the affected joint cavity. The resorption was evaluated by the antibiotic concentration in the urine on the second day after its injection. Absorption of 38.5-44.9% tetracycline corresponded to stage 0; 56.6-62.0% to stage I; and 69.4-80.1% to stage II of the inflammatory process activity. A trial of the method has shown good correlation between the tetracycline absorption and the stage of the inflammatory process activity in the synovial membrane as proved histologically.