Interventional Management of Canine and Feline Benign Ureteral Obstructions

Hydronephrosis and hydroureter secondary to ureteral stricture due to congenital circumcaval ureter and concomitant levoposition of the caudal vena cava in a Bernese Mountain Dog

“…In our case, it was not possible to determine when the obstruction started, but a chronic condition was assumed. This information is crucial in terms of selecting the best treatment for ureteral obstruction because the technique of choice mostly depends upon the underlying cause and functionality of the affected kidney 9 . In experimental dog‐model ureteral obstructions, the glomerular filtration rate (GFR) declined by up to 54% after 14 days of constriction and, even solving the cause of obstruction, GFR values do not improve if the surgery is performed 40 days after the obstruction started 10 .…”

“…2,11,12 Moreover, good parenchymal and functional recovery has been described in cats with ureter obstruction (with and without circumcaval ureter) after subcutaneous ureteral bypass or stent treatment. 2,12 When the status of this dog was discussed with the owners, a stenting solution was dismissed because of the ureter and CVC conformation and the major risk of re-obstruction, 2,9 and subcutaneous ureteral bypass or nephroureterectomy was recommended instead. Some limitations to predict renal recovery options were found in our case since a functional evaluation of the kidneys was not performed, and previous imaging tests of the abdomen were not available.…”

IMAGING DIAGNOSIS—RADIOGRAPHY AND ULTRASONOGRAPHY OF BILATERAL CONGENITAL URETEROVESICAL JUNCTION STENOSIS CAUSING HYDRONEPHROSIS AND HYDROURETER IN A FERRET (MUSTELA PUTORIUS FURO)

“…Disruptions of diverse factors and genetic pathways involved in the normal development processes of the urinary tract (induction of the metanephric kidney, establishment of the urinary conduit, or maturation of the pyeloureteral peristaltic machinery) have been linked with ureteral obstruction in humans . Patients suffering from this condition may remain asymptomatic, and can be diagnosed later in life, or may present with clinical signs such as dysuria, hematuria, abdominal pain, vomiting, anorexia, weight loss, and lethargy, or signs of severe anuric acute renal failure in bilateral ureteral obstruction …”

“…The primary goal of surgery is to improve renal drainage and decrease the excessive hydrostatic pressure on the renal parenchyma, which will ultimately improve and preserve renal function . Ureteral stents or SUB devices are nowadays replacing the traditional surgical interventions as they are considered safer and less‐invasive techniques . Surgical manipulation of the ureter is associated with a high risk of stricture formation, often resulting in recurrence of obstruction.…”

“…In our case, the SUB device seemed to provide an alternative and functional option because of its modifiable length, as no compatible stent size for ferrets is available. Complications associated with SUB device placement are re‐obstruction, urine leakage, kinking of the device, and urinary tract infection . Finally, the SUB device was removed due to obstruction and persistent urinary tract infection, and a bilateral ureteroneocystostomy was performed.…”