The ureter is a tube which carries urine from the kidney to the bladder. In cases of an ectopic ureter, an abnormality in development leads to the ureter failing to connect to the bladder and instead connects to another part of the body, usually the urethra, vagina, colon, or uterus. This can be bilateral (affecting both kidneys) or unilateral (affecting one kidney).
The condition is not life-threatening, but concurrent urinary tract infections are very common and should be treated promptly to avoid potentially fatal kidney infection.
Ureteral ectopia is usually unilateral. Symptoms vary in that some affected dogs are able to urinate normally some of the time, while others are incontinent continuously. Some dogs only leak urine when in certain physical postures.
While the condition is most often identified in young animals, affected male dogs may not develop urinary incontinence until they are adults. Urinary leakage can cause skin infections around the genital area. If ureteral outflow is restricted before or after attempted surgical correction, urine can back up into the kidneys and cause hydronephrosis (fluid build up in the kidneys), which is a serious condition characterized by loss of appetite, lethargy, excessive thirst and urination, bloody urine (hematuria), bad breath (halitosis), mouth sores, vomiting, and abdominal distention.
Ectopic ureter is uncommon in dogs, and more common in females than in males. Certain breeds seem predisposed to this condition, such as West Highland White Terriers, Fox Terriers, Miniature and Toy Poodles, Siberian Huskies, and Labrador Retrievers.
Ureteral ectopia is a congenital anomaly that occurs during fetal development. There is thought to be a genetic component, but the pattern of inheritance has not been identified.
Ectopic ureters may be asymptomatic.
The first step to diagnose a possible case of ureteral ectopia is a thorough physical exam including close examination of the urogenital area. From there, urinalysis, urine culture, and blood work is performed to rule out other causes of incontinence.
Ectopic ureter(s) are definitively identified with diagnostic imaging or cystoscopy which can sometimes correct the ureter at the same time.
Treatment for ectopic ureter is surgery to connect the affected ureter(s) to the correct location in the bladder, or to completely remove the abnormal ureter with its attached kidney. Minimally invasive techniques like endoscopically assisted laser ablation are now available as an alternative to surgery; this often requires referral to a specialist. Urinalysis and urine culture follow-ups at regular intervals are strongly recommended. Further supportive care such as assisted urination and treating external rashes are also necessary. Prognosis is good, although many dogs still have some incontinence post-operatively.
Studies estimate that approximately 50-75% of dogs with ectopic ureters will no longer experience incontinence after appropriate treatment. Persistent urinary incontinence is the most common complication following surgery or a minimally invasive repair technique. Many dogs who undergo any of the procedures still have urinary leakage. If this occurs, additional medications are required to control urination for the rest of life. 25–70% of female patients may still experience chronic urinary incontinence despite surgery and medication therapy.
As ureteral ectopia is a congenital condition that occurs during fetal development, the only prevention possible is to avoid breeding affected dogs or their close relatives.
Ectopic ureter is a rare condition in dogs.