Association of HLA-B27 antigen with retroperitoneal fibrosis.

This is the second known case of retroperitoneal fibrosis in a middle-aged black man whose tissue type was HLA-B27 positive. The HLA-B27 antigen is present in only 4 per cent of black American male subjects and may be important in the diagnosis and management of patients with primary retroperitoneal fibrosis. A genetic predisposition is suggested for the development of idiopathic primary retroperitoneal fibrosis in patients who are HLA-B27 antigen positive.