A Case of Postrenal Acute Kidney Injury Complicating Retroperitoneal Fibrosis Associated with Autoimmune Pancreatitis

Abstract

Autoimmune pancreatitis is a recently established clinicopathologic entity often associated with various types of other autoimmune diseases. We report a case of postrenal acute kidney injury (AKI) due to retroperitoneal fibrosis associated with autoimmune pancreatitis. The seventy one year old male patient was admitted because of oliguria and lower extremity edema. He had been diagnosed to have autoimmune pancreatitis and retroperitoneal fibrosis by increased serum IgG and IgG4 level with the presence of rim like attenuation around pancreas and the retroperitoneal fibrosing mass in abdominal CT scan 1 year ago but was lost to follow up. Magnetic resonance cholangiopancretogram and follow up abdominal CT scan showed progressed retroperitoneal fibrosis with newly developed bilateral hydronephrosis and atrophied left kidney despite partial improvement in pancreatitis. Because of progressively rising serum creatinine and oliguria, percutaneous nephrostomy in right kidney was performed. Steroid treatment was initiated with insertion of double J catheter at right ureter and renal function gradually returned. We report here a rare case of postrenal AKI developed in unilateral functioning kidney complicated by combined retroperitoneal fibrosis and autoimmune pancreatitis.