Ectopic Ureters - Marty's rare condition
Marty, an adorable golden retriever puppy, was just 15 weeks old when he first presented to the VSA team in Sylvia Park. He presented initially to the medicine department for urinary incontinence which was occurring when Marty was awake, lying at rest and when asleep. The owners adopted Marty at 8 weeks old and first noticed signs of urine leakage approximately one week later. Marty was otherwise a bright and clinically well puppy.
Further investigation was needed to determine the underlying cause of Marty’s incontinence. Marty was kept in hospital for a day as Dr Wen-Jie Yang recommended a collection of diagnostic tests that initially consisted of blood work (biochemistry and haematology panel), a urine sample for culture, urinalysis, and an abdominal ultrasound.
The biochemistry renal parameters of creatinine were within normal reference range with phosphate mildly elevated. Urine culture, urinalysis and haematology were all unremarkable. Abdominal ultrasound showed that the kidneys were severely enlarged (>95mm length) with marked hydronephrosis (swelling of the kidneys). Both ureters (tubes that transport urine from the kidneys to the bladder) were severely distended (>33mm diameter) with a highly tortuous path and terminated at the cranial aspect of the prostate gland. Conclusions of the ultrasound showed that Marty had bilateral ureteral ectopia with very severe secondary hydroureter and hydronephrosis caused by ureterocoeles.
A ureterocoele is simply a swelling limited to the end of the ureter as it enters the bladder and can be associated with urine refluxing backward to the kidney causing enlargement due to a build-up of urine (hydronephrosis). The ureterocoeles were likely responsible for both Marty’s incontinence and hydronephrosis.
Ectopic ureters (abnormal location of the ureters) are a rare finding in dogs but are the most common congenital anomaly that causes urinary incontinence. The disease is thought to arise because of disruption in normal embryogenesis (the process of embryo development).
Hydronephrosis leads to kidney damage, however, Marty’s most recent kidney parameters had improved compared to previous blood testing which was good news. While Marty was not displaying obvious pain, hydronephrosis can be a painful disease and he was sent home with gabapentin to help control any underlying pain.
The severity of this condition meant that without surgery, Marty would soon succumb to end stage renal failure with a grave prognosis. It became clear from the diagnostic test results that Marty was a puppy with a big problem. Surgery was Marty’s last hope, and he was transferred to the surgical team at VSA. A CT scan of Marty’s abdomen with a negative contrast cystography (an injectable contrast dye to help visualise the bladder) was recommended to further characterise the urinary tract pathology and facilitate pre-surgical planning.
This scan was performed a week later. CT scans are an excellent form of imaging as they offer a much higher level of detail compared to standard X-rays and can create a 360-degree view of the body’s internal structures. Dr Richard Jerram reviewed the CT results and discussed Marty’s significant urinary tract abnormalities and surgical options with his owners. Results confirmed bilateral extramural ectopic ureters. The extreme nature of the bilateral hydroureter and hydronephrosis was indicative of a chronic partial obstruction at the point where the ureters enter the bladder (ureteral termination) whilst the severe distension of the urinary bladder was thought to be due to compression of the bladder neck by the overlying ureters.
Surgical treatment was scheduled a week later and consisted of abdominal surgery to perform neo-ureterostomy bilaterally. This procedure involves creating a new ureter opening where the distal portion of the ureters are relocated so that they enter the bladder in the correct anatomical location.
Even though this surgical approach would aid in resolving Marty’s immediate problem (relieving urine build up) and hence improve renal function, Marty’s urinary incontinence was expected to continue. Further surgery may be necessary, assuming that Marty does not progress into renal failure. This would involve placement of ureteral stent devices (subcutaneous ureteral bypass device and a hydraulic urethral sphincter occlusion device) to improve the incontinence by maintaining the flow of urine from the kidneys to the bladder when the ureter becomes obstructed.
Marty, being a resilient little puppy, recovered well from major urinary tract surgery. An indwelling urinary catheter was placed to assess his urine flow. He appeared to be producing good urine from the kidneys with no evidence of further renal deterioration indicating that the neo-ureterostomy sites were flowing well.
Once it was clear that Marty could urinate without the need for the urinary catheter, he was discharged 3 days post-surgery with pain relief, antibiotics and strict 2 week confinement – no easy task for a energetic puppy!
One month following his ectopic ureter surgery, Marty has been making excellent progress at home. He is now able to urinate with no evidence of incontinence. A repeat abdominal ultrasound evaluation was performed which confirmed functioning ureters with some renal improvement but with continued dilation of the ureters bilaterally.
While Marty is not out of the clear yet, with the help of his committed owners, he still has a long road to recovery that involves repeat ultrasound exams and bloodwork to assess his ongoing renal function. Due to the severe nature of Marty’s condition, his long-term prognosis remains uncertain.
The VSA team have our fingers crossed for Marty and he looks like he is heading in the right direction – go Marty!