ABSTRACT
A 76 year old man was admitted because of periumbilical aMominal pain and nausea for 20days before admission. Initial serum creatinine level was 6.1mg/dL. Radioisotope renography showed obstruc- tive uropathy in both ureters. Retrograde pyelography of the left kidney revealed about 1cm of filling defect on the level of L5. Percutaneous nephrostomography of the right kidney revealed ureteral stricture in the lower ureter. In order to preserve renal function, a double J stent was inserted into each ureter. Serum creatinine level decreased to 1.5mg/dL after the insertion of ureteral stents. 12 weeks later, both stents were removed. 3 months after removal of the ureteral stents, retroperitoneal fibrosis and hydronephrosis disappeared in follow up abdominal CT. Recent his serum creatinine has shown about 1.5mg/dL. The patient is under continuing observation with serum creatinine level and sonography for detection of recurrence. This is a rare case of retroperitoneal fibrosis which showed spontaneous regression after ureteral stent insertion for 12 weeks without ureterolysis or corticosteroid therapy. In this case, the ureteral stent played a important role in preserving renal function by relieving ureteral obstruction. But the key point was that in the early stage in the early stage of retroperitoneal fibrosis, it was thaught having reversible process. There are some reports that ureteral obstruction was relieved only by correction of fluid and electrolytes balance or ureter diversion such as percutaneous nephro-stomy. Corticosteroid therapy promotes this rever-sible change in early stage of this disease by immunosuppression and antiinflammatory reaction. But once fibrosis has established in late stage of retroperitoneal fibrosis, corticosteroid is not effective for reducing the fibrosis and ureteral obstruction. In that case, operation is the choice for preservation of renal function. We reported an idiopathic retroperitoneal fibrosis case which showed spontaneous regression after preserving renal function by double J stent insertion without ureterolysis or corticosteroid therapy. We thought that idiopathic retroperitoneal fibrosis is a reversible process in the early stage.