Related Experiment Video
Updated: Apr 4, 2026

Unilateral Ureteral Obstruction Model for Investigating Kidney Interstitial Fibrosis
Published on: April 25, 2025
Chronic, nonspecific, postinfectious, retroperitoneal fibrosis and ureteral obstruction
Angelo Territo1, Salvatore Micali1, Antonio Manenti2
1Department of Urology, University of Modena and Reggio Emilia, Modena - Italy.
Introduction:
Two cases of severe ureteral obstruction following nonspecific, postinfectious, chronic retroperitoneal fibrosis are described, which both originated by a primitive intestinal pathology.
Patients:
This complication was observed in two women: first, 65 years old, submitted for ulcerative colitis to a total proctocolectomy, with ileo-pouch-anal anastomosis, complicated by an anastomotic fistula; and second, 66 years old, operated with an extended left hemicolectomy, for an adenocarcinoma of the recto-sigmoid colon complicated with a vaginal fistula. In these cases, computerized tomography demonstrated a unilateral hydronephrosis, secondary to a complete obstruction of the ureter; a subsequent nephro-ureterectomy became necessary. Histology demonstrated nonspecific inflammatory lesions.
Discussions:
Postinfectious, chronic inflammation of the retroperitoneum acts on the ureteral and peri-ureteral tissues, inducing an inflammatory and then a fibrotic process.
Conclusions:
We underline the opportunity of a precocious and radical treatment of every retroperitoneal infection.
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