Ectopic Ureter

The most common clinical sign is continuous urinary incontinence. Owners often report urine leakage while at rest and while the dog is walking. Dogs often are noted to urinate normally outside. Some owners may complain that they have had difficulty house training the puppy. In some dogs, incontinence may be intermittent or only occur at rest or while sleeping. In a small number of dogs, the only clinical signs may be recurrent infections.

Ectopic ureters are typically diagnosed based on history and diagnostic imaging findings. Abdominal ultrasound may be helpful in identifying an ectopic ureter, but false negative and false positive results can occur. Ultrasound is better for evaluating the kidneys for concurrent abnormalities. Definitive diagnosis is best made using either CT excretory urography (EU) or cystourethroscopy. For CT EU, we recommend that the patient be placed in sternal recumbency. A urethral catheter should be placed to empty the bladder and instill air as a negative contrast agent in the bladder and urethra. This allows better visualization of the course of the ureters. Cystourethroscopy (evaluation with an endoscope) allows for diagnosis of ectopic ureters as well as evaluation for other congenital abnormalities such as persistent paramesonephric remnant.

Traditionally, ectopic ureters have been corrected using surgical procedures. This is still necessary for extramural ectopic ureters. For intramural ectopic ureters, there is a procedure call cystoscopic-guided laser ablation (CLA) which is available at CVTES. Advantages of this procedure include lack of incisions and being an outpatient procedure.

In most cases, we will want to verify or diagnose the ectopic ureter by cystourethroscopy. Ideally, if an ectopic ureter is present we will perform the CLA during the same procedure. In order to perform the CLA procedure, any urinary tract infections must be resolved. Prior to referral, a urinalysis and urine culture should be performed (preferably from a cystocentesis sample). We recommend that the referral laboratory hold the culture for at least 5 days prior to reporting no growth. We have seen infections with Corynebacterium in ectopic ureter cases and this bacteria is slow growing. It can be easily missed on cultures grown for only 48 hours. If an infection is present, appropriate antibiotic therapy should be started and a urine culture repeated in 7-10 days. If the repeat culture is negative, the patient can be continued on therapy and be referred for evaluation and possible CLA. If the initial culture is negative, the patient can be referred for evaluation. We will typically perform a urinalysis on the day of evaluation to see if any signs of infection are present.

Similar to surgery, full continence occurs in ~50% of dogs with CLA alone. In the other 50%, some degree of urinary incontinence continues usually due to concurrent urethral sphincter mechanism incompetency which is a common concurrent finding in dogs with ectopic ureter. In cases that remain incontinent, we recommend medication trials with phenylpropanolamine (PPA) and/or an estrogen supplement (Incurin or DES). This increases the complete continence rate to ~60-70%. In dogs remaining incontinent with medications, options include surgical placement of a urethral occluder device or endoscopic injection of a urethral bulking agent (e.g., collagen). These procedures result in a complete continence rate >80%.