The Case of the Leaky Corgi
1. Referral:
“S’mores” is a two-year-old male neutered Corgi who presented for a three to four week history of dribbling urine. He was treated for a suspected urinary tract infection at that time with a 2 week course of antibiotics. There was mild improvement noted which lasted a few days, but clinical signs resumed while still on antibiotic therapy. On revaluation immediately prior to referral, a severely distended bladder was identified on abdominal radiographs. Initial bloodwork and urinalysis were unremarkable. “S’mores” was catheterized and 250ml of urine was evacuated. An incompletely emptied bladder was noted on repeat radiographs. On presentation to the emergency service at ASG, the owners reported stranguria while posturing, incontinence with no hematuria.
2. Exam:
On physical exam, “S’mores” was BAR and vital signs were within normal limits. Palpation of the abdomen revealed a markedly enlarged bladder that was unable to be expressed. No other significant findings were noted on physical examination.
3. Procedures:
We discussed urinary tract infection, urinary obstruction (urethritis, stenosis, calculi and anatomic anomaly) and neurogenic (reflex dyssynergia) differentials with the owners. “S’mores” was transferred to the medicine service for further imaging of the urinary system. An abdominal ultrasound was performed and a cystic structure was noted at the trigone of the bladder. The left renal pelvis and proximal ureter had moderate dilation.
4. Diagnosis:
Based on ultrasound a diagnosis of a left-sided ureterocele was made. “S’mores” was then transferred to the surgical service for correction.
5. Treatment:
A double contrast cystogram and excretory urography was performed to evaluate the anatomic location of the ureters. A contrast enhancing structure was noted in the caudal bladder which appeared contiguous with the left hydroureter. Both ureters appeared to enter the bladder at a normal location. A cystotomy was performed and a 2.5-3 cm ureterocele was identified over the mucosal orifice of the left ureter. An incision was made into the ureterocele, and the left ureter was catheterized with an 8 Fr. red rubber catheter. The ureterocele was resected to submucosa and the defect was closed mucosa to mucosa. Anesthesia and recovery were uneventful. “S’mores” had continued stranguria postoperatively, likely from urethra and/or ureteral spasm, which was responsive to phenoxybenzamine.
6. Discussion:
The etiology of the development of ureteroceles is unknown. There have been many theories including an obstructive etiology with subsequent dilation which was first proposed in 1927. A congenital anomaly has also been proposed due to a delay in establishment of the lumen of the ureteral bud in development of the distal ureteral segment. Many lesions are incidentally identified in humans, but clinical signs can be identified. Lower urinary tract disease is the most common clinical sign including recurrent urinary tract infection, incontinence, and stranguria. Reported diagnostics include ultrasonography, contrast radiography and cystoscopy. Treatment is largely dependent on the classification of the ureterocele and includes both endoscopic and surgical options. Many classification schemes have been developed in humans and no single scheme has been accepted in veterinary patients. One classification scheme is based on location of the ureterocele in regards to the entry of the ureter into the bladder. Ureteroceles can be located normally within the bladder (orthotopic) or located within the bladder neck and urethra (ectopic). The ureterocele in this case was located in a normal anatomic location and was classified as orthotopic.
7. Recovery:
On follow-up one month postoperatively, the owner reports “S’mores” was doing great with no clinical signs of lower urinary tract disease.
by Zachery Smith, DVM
Michael Huber, DVM, MS, DACVS
*Photo of corgi is not “S’mores.”