Double pigtail ureteral stenting and renal pelvic lavage for renal-sparing treatment of obstructive pyonephrosis in dogs: 13 cases (2008-2012).

OBJECTIVE

To describe the technical aspects and clinical outcome of endoscopic- and fluoroscopic-guided ureteropelvic lavage and ureteral stent placement for treatment of obstructive pyonephrosis in dogs.

DESIGN

Retrospective case series.

ANIMALS: 13 client-owned dogs (14 obstructed ureters).

PROCEDURES: All patients with obstructive pyonephrosis were treated with a ureteral stent. Medical records were reviewed for history, clinical signs, pre- and postprocedural clinical and imaging data, and short- and long-term outcomes.

RESULTS

13 dogs (14 ureters) had unilateral or bilateral ureteral obstructions and pyonephrosis due to ureterolithiasis (n = 13) or a suspected ureteral stricture (1). Eleven dogs had positive results of bacteriologic culture of urine obtained from the bladder, renal pelvis, or both. Ten were thrombocytopenic, and 8 were azotemic. Stents were placed fluoroscopically with endoscopic (n = 11) or surgical (3) assistance. Median hospitalization time was 48 hours (range, 6 to 260 hours). Median follow-up time was 480 days (range, 2 to 1,460 days). Intraoperative complications occurred in 2 patients (stent occlusion from shearing of a guide wire, and wire penetration of the ureter at the location of a stone). Short-term complications included a bladder hematoma (n = 1) and transient dysuria (1). Long-term complications included stent encrustation (n = 1), stent migration (1), and tissue proliferation at the ureterovesicular junction (5), which had no clinical implications. Recurrent urinary tract infections were documented in 7 dogs.

CONCLUSIONS AND CLINICAL RELEVANCE: Ureteral stenting was a successful renal-sparing treatment for obstructive pyonephrosis in dogs and could often be performed in a minimally invasive manner. There were few major complications. This technique may be considered as an effective treatment option for this condition in dogs.