Clinical outcomes and management of idiopathic retroperitoneal fibrosis: a case series

Idiopathic retroperitoneal fibrosis (IRF) is a rare fibro-inflammatory disorder that often leads to ureteral obstruction and renal impairment. This case series evaluated clinical presentation, diagnostic evaluation, management strategies, and outcomes in nine patients diagnosed with IRF at a single tertiary center.

We retrospectively reviewed nine patients diagnosed with IRF between January 2015 and December 2024. Clinical presentation, comorbidities, laboratory parameters, imaging findings, targeted immunologic and pathology tests, treatment regimens, and longitudinal outcomes were extracted from electronic medical records.

All nine patients (100%) presented with hydronephrosis, bilateral in eight (89%) and unilateral in one (11%). Biopsy to exclude malignancy was performed in six patients (67%). Medical therapy comprised prednisone alone or in combination with mycophenolate mofetil in six (67%) and azathioprine in two (22%). Ureteral stenting was performed in seven patients (78%). Clinical improvement occurred in eight patients (89%), radiologic improvement in six (67%), and renal function stabilized or improved in all cases (100%). Complications occurred in five patients (56%): acute kidney injury in two (22%), persistent unilateral renal nonfunction in two (22%), and chronic kidney disease in one (11%).

IRF posed significant diagnostic and therapeutic challenges. Early use of multimodal imaging enabled prompt diagnosis, and combined corticosteroid plus immunosuppressive therapy achieved high rates of clinical response, but was associated with notable morbidity, underscoring individualized management and close monitoring.