RETROPERITONEAL FIBROSIS AND ARTHRITIS - MANIFESTATION OF THE SAME DISEASE

Retroperitoneal fibrosis is a disorder in which the retroperitoneal fa t is the site of a subacute and chronic inflammatory reaction and is s ubsequently replaced by dense fibrotic tissue. Rheumatoid nodules are chronic granulomata occurring at sites of pressure and movement, both near the body surface and internally. A 55-year-old sales-manager was admitted to radiation synovectomy after a 5 year history of excessive right and left knee effusions. There were no other clinical or laborat ory abnormalities. The patient did not respond to either radioisotope synoviorthesis using radioactive Yttrium (90 Y), or to open synovectom y and prostetic surgery of the right knee. One year later, surgery of left ureter was necessary. Histological findings revealed the diagnosi s of Ormond's disease. Comparative histological studies of synovial me mbrane of knee and retroperitoneal tissues showed local necrosis, fibr in deposition, lining cell proliferation, and infiltration by lymphocy tes. Diagnosis of arthritis complicated by retroperitoneal rheumatoid nodules and retroperitoneal fibrosis was made. Serum rheumatoid factor has been negative. For the last 3 years, the patient has been on succ essful therapy with azathioprine. Rheumatoid nodules of the retroperit oneum have vanished completely and frequency of knee effusions decreas ed.