Retroperitoneal fibrosis presenting as acute renal failure

Background A 60-year-old man with a history of atherosclerotic disease of the carotid and coronary vasculature presented with lower back pain and acute renal failure. Imaging studies revealed bilateral ureteral obstruction by a large retroperitoneal mass. Investigations Physical examination, urine and blood analysis, catheterization, radiography of the chest, abdominal and pelvic CT, magnetic resonance angiography, renal ultrasound and biopsy of mass. Diagnosis Retroperitoneal fibrosis. Management Ureteral stenting, laparoscopic ureterolysis, and immunosuppressive therapy with prednisone and mycophenolate mofetil.