[Retroperitoneal fibrosis: about 12 cases].

Retroperitoneal fibrosis (RPF) is rare. It is characterized by the gradual transformation of retroperitoneal adipose tissue into a fibrous mass surrounding the aorta, the inferior vena cava and the urinary tract responsible for progressive alteration in the renal function. It usually manifests as lumbar pain associated with renal failure and biologic inflammatory syndrome. We report 12 cases of retroperitoneal fibrosis in order to determine its clinical, radiological and therapeutic features. We conducted a retrospective study of 12 patients with retroperitoneal fibrosis whose medical data were collected in the Departement of Urology at the University Hospital Hassan II, Fes over a period of 9 years (2005-2013). The study involved ten men and two women. Clinical symptomatology was very variable, dominated by lumbar pain in all patients and hydrocele in 1 patient. Laboratory tests showed renal failure in all patients and inflammatory syndrome in 10 patients. The diagnosis of retroperitoneal fibrosis was suspected in all patients on ultrasound showing obstruction of the upper urinary tract without visible obstacle. The diagnosis was confirmed by abdominal CT scan without contrast that objectified a retroperitoneal tissue lesion enveloping the vessels and the urinary tract. Nine patients had idiopathic retroperitoneal fibrosis. Two patients had perianeurysmal fibrosis and one patient had post-radiation fibrosis. All patients underwent urinary drainage by double J. ureteral catheter. Seven patients underwent corticosteroid therapy. Six patients had an improvement of clinical and laboratory test outcome with disappearance of pain and improvement of the general condition. This study confirms the rarity of retroperitoneal fibrosis, the difficulty of diagnosis, pain associated with inflammatory syndrome and renal failure as common manifestations. Abdominal CT scan without contrast is the gold standard for definitive diagnosis. Urinary drainage is essential in most cases as well as regular monitoring of patients.