MULTIPLE EXTRAARTICULAR SYNOVIAL CYST FORMATION - CASE-REPORT AND REVIEW OF THE LITERATURE

Objective-To investigate the clinical manifestations and the treatment strategy of a very rare entity of disease manifesting as multiple ext ra-articular cystic synovitis with recurrent polyarthralgia. Methods-A 47 year old male patient with multiple extra-articular synovial cysts was followed up prospectively for 13 years. The clinical manifestatio ns and response to various treatments were recorded. Comparisons are m ade among the five reported cases (including the present case). Result s-Multiple synovial cysts over the tendon sheath and bursae appeared s uccessively with and without antecedent growth of nodules during 13 ye ars of follow up. Although polyarthralgia and high titred rheumatoid f actor persisted throughout the course, there were no roentgenographica l changes of joints specific to rheumatoid arthritis (RA). The synovia l cysts and arthralgia failed to respond to any of the disease modifyi ng anti-rheumatic drugs (DMARDs) prescribed. Systemic involvements suc h as pulmonary interstitial fibrosis and skin ulcers were also noted, but they were not progressive. Conclusions-Multiple extra-articular cy stic synovitis is an uncommon disease entity closely related to RA. It has been reported exclusively in Japanese subjects and therefore some cultural factors, either genetic or environmental, may contribute to its development.