Endoscopic placement of ureteral stents for treatment of congenital bilateral ureteral stenosis in a dog.

Case Description: A 5-year-old 8.6-kg (18.9-lb) spayed female Pug was evaluated because of chronic hematuria and recurrent urinary tract infections.
Clinical Findings: Excretory urography, ultrasonography, and excretory CT urography were performed. Results indicated that the dog had bilateral hydronephrosis and hydroureter and suspected proximal ureteral stenosis. Retrograde ureteropyelography confirmed the presence of stenosis at the ureteropelvic junction of each ureter, along with a large amount of endoluminal ureteral debris. Clinical findings suggested that the dog had a congenital bilateral anomaly of the upper urinary tract.
Treatment and Outcome: The dog was anesthetized, and 2 double-pigtail ureteral stents were placed cystoscopically with fluoroscopic guidance for immediate relief of the ureteropelvic junction obstructions. Each stent extended from the left or right renal pelvis to the urinary bladder. The procedures and the patient's recovery from anesthesia were uncomplicated. Continuing improvements in severity of hydronephrosis, hydroureter, and dysuria were evident during routine follow-up examinations at 2, 4, 12, 16, and 45 weeks after stent placement. Over the subsequent 12 months, all clinical signs remained resolved other than a urinary tract infection that was successfully treated with antimicrobials.
Clinical Relevance: Ureteral stenosis should be considered as a differential diagnosis for hydronephrosis in dogs, particularly when urinary tract calculi or neoplasia is not present. Chronic hematuria and recurrent urinary tract infections can be associated with this condition. Placement of ureteral stents may be a successful treatment option for ameliorization of congenital ureteral obstructions.