Background Retroperitoneal fibrosis (RPF) is rare disease wich presents with bilateral hydronephrosis as the most common symptom.

Objectives One of the aims in the treatment of retroperitoneal fibrosis (RPF) is to restore renal drainage and maintain renal function. We investigated the rate of ureteral stent-freedom after conservative and surgical therapy

Methods Patient data was retrospectively analyzed. For primary diagnostics CT or MRI imaging was used as well as for treatment monitoring.

Results Between 1995 and 2010 33 patient (21men; 12 women) were treated for RPF at our institution. The median follow-up was 55 months, the median age 60y. In addition to imaging studies 15 pat. were biopsied for diagnosis. 29 patients received immunosuppressive therapy, in 16 (66%) cases as combination therapy. 25 pat. presented with hydronephrosis at time of the primary diagnosis. Overall for 40 renal units ureteral stenting was necessary. After initiation of the medical treatment 22 (76%) patients showed a stable disease or disease regression in follow-up imaging. In 7 cases an addiditional laparoscopic urerolysis was performed. After 6 months 7 (18%) renal units were stent-free. Until the end of 2011 another 10 renal units became stent-free, with a median time to stent freedom of 22 months. Of the patient with an ureterolysis 4 patients were stent-free after 12 months. Three patients had to receive nephrectomy 55 months (mean) after the initiation of the immunosuppression. At the end-point of our analysis the median creatinin-level was 1.05mg/dl, 3 patients needing dialysis.

Conclusions The medical treatment of RFP was complex and lead to freedom of ureteral stenting in 39% of cases only. If a surgical treatment at an earlier stage leads to superior stent-free rates remains to be further elucidated.

Disclosure of Interest None Declared