Technical and clinical outcomes of ureteral stenting in cats with benign ureteral obstruction: 69 cases (2006–2010)

Abstract

OBJECTIVE--To evaluate the technical, short-term, and long-term outcomes in cats with benign ureteral obstructions treated by means of double-pigtail ureteral stent placement. DESIGN--Retrospective case series. ANIMALS--69 cats (79 ureters). PROCEDURES--The diagnosis of benign ureteral obstruction was made via abdominal ultrasonography, radiography, and ureteropyelography. Ureteral stent placement was attempted endoscopically, surgically, or both, with fluoroscopic guidance. The medical records were reviewed for pre-, intra-, and postoperative data; complications; and outcome. RESULTS--69 cats (79 ureters) had stent placement attempted for various causes: ureterolithiasis (56/79 [71%]), stricture (10/79 [13%]), both ureterolithiasis and stricture (12/79 [15%]), or a purulent plug (1/79 [1%]). Stent placement was successful in 75 of 79 ureters (95%). Median number of stones per ureter was 4 (range, 0 to > 50), and 67 of 79 (85%) had concurrent nephrolithiasis. Preoperative azotemia was present in 95% (66/69) of cats (median creatinine concentration, 5.3 mg/dL [range, 1.1 to 25.8 mg/dL]), and 71% (49/69) remained azotemic (median, 2.1 mg/dL [range, 1.0 to 11.8 mg/dL]) after successful surgery. Procedure-related, postoperative (< 7 days), short-term (7 to 30 days), and long-term (> 30 days) complications occurred in 8.7% (6/69; 7/79 ureters), 9.1% (6/66), 9.8% (6/61), and 33% (20/60) of cats, respectively; most of these complications were minor and associated with intermittent dysuria or the need for ureteral stent exchange. The perioperative mortality rate was 7.5% (5/69), and no deaths were procedure related. The median survival time was 498 days (range, 2 to > 1,278 days). For patients with a renal cause of death, median survival time was > 1,262 days, with only 14 of 66 cats (21%) dying of chronic kidney disease. Nineteen (27%) cats needed a stent exchange (stricture in-growth [n = 10], migration [4], ureteritis [2], dysuria [2], pyelonephritis [1], or reflux [1]). No patient died of the procedure or recurrent ureteral obstruction. CONCLUSIONS AND CLINICAL RELEVANCE--Results of the present study indicated that ureteral stenting is an effective treatment for benign ureteral obstructions in cats regardless of obstructive location, cause, or stone number. The perioperative morbidity and mortality rates were lower than those reported with traditional ureteral surgery. The short- and long-term complications were typically minor but may necessitate stent exchange or use of an alternative device, particularly with ureteral strictures. The prognosis for feline ureteral obstructions after ureteral stenting could be considered good when the procedure is performed by trained specialists.

Uso de glucagon no manejo de obstrução ureteral em um gato com doença renal crônica: relato de caso

“…Em dois estudos as fêmeas representaram a maior parte dos casos. A idade média dos gatos acometidos é de oito anos, podendo variar de dois a 16 anos (Kyles et al, 2005;Berent et al 2014), com relato de gatos com oito meses (Kyles et al, 2005) e dez meses (Mestrinho et al, 2013) de vida.…”

“…A principal causa de obstrução ureteral em gatos é a ureterolitíase com prevalência de mais de 70%. Outras causas incluem a estenose ureteral (congênita ou adquirida), neoplasia, ureter circuncaval, tampão purulento ureteral e coágulos solidificados (Zaid et al, 2011;Horowitz et al, 2013;Berent et al, 2014).…”

“…A ocorrência da ureterolitiase está presente em 52% a 71% dos casos, entretanto pode ainda ser maior quando associada a estenose, chegando a representar 86% dos casos de obstrução ureteral (Horowitz et al, 2013;Berent et al, 2014). A estenose ureteral concomitante a urolitíase localizada em outro local que não o da obstrução, indica a predisposição a formação de estenose em gatos.…”

“…No momento do diganóstico 95% dos gatos com obstrução ureteral estão azotêmicos (Berent et al, 2014). As alterações renais visualizadas nos exames ultrassonográficos, sugerem a existência de doença renal crônica preexistente no momento do diagnóstico da obstrução ureteral (Kyles et al, 2005;Roberts et al, 2011).…”

“…A concentração da creatinina sérica é o mais significante preditor do tempo de sobrevida. Assim, a descompressão ureteral com tratamento apropriado e agressivo é a melhor chance de bons resultados a longo tempo (Horowitz et al, 2013;Berent et al, 2014).…”