Retroperitoneal fibroses--an association with hyperuricaemia.

A review of a small series of cases with idiopathic retroperitoneal fibrosis revealed that two of the patients had been under treatment for gout prior to developing retroperitoneal fibrosis. Investigation showed that other patients in the series had hyperuricaemia. Examination of the retroperitoneal fibrotic tissue demonstrated the presence of urate crystals in unusually high numbers. It is suggested that the pathological process of retroperitoneal fibrosis in these cases may have been initiated by the deposition of urate crystals in the retroperitoneal connective tissue and that the same process may be related to the causation of idiopathic hydrocoele.