Abnormal Urine Outflow Due to Bladder Dysfunction in Dogs

Abnormal urine outflow due to urinary bladder dysfunction can be caused by incorrect development of the ureters, which are responsible for moving urine from the kidney to the bladder, or by deformities in the urachus.  The urachus is a tube that connects the bladder to the umbilical cord to remove waste before birth, and closes and atrophies after birth, becoming a solid cord of tissue between the bladder and the naval. When this cord does not close properly it can cause cysts and urine leakage, as well as increase the chance that cancer can form on the cord itself.

Ectopic ureters and urachal disorders are developmental conditions that can cause an abnormality in the flow of urine through the body.

Both ectopic ureters and urachal disorders sometimes present with no outward symptoms. Those symptoms that do present are similar to the symptoms of a urinary tract infection.

• Blood in urine (Hematuria)
• Cloudy urine
• Difficulty with urination (Dysuria)
• Foul smelling urine
• Incontinence
• Increase in frequency of urination (Pollakiuria)
• Inflammation of genital area in females 
• Leakage of urine from the naval (generally in newborns)

Types

Ectopic ureter

• The ureter is a tube that carries urine from the kidneys to the bladder
• In the case of an ectopic ureter, this tube ends in the wrong place which causes intermittent urine leakage
• This is a developmental defect

Urachal disorders

• The urachus is a tube that connects the bladder to the umbilical cord to remove waste before birth
• This tube normally atrophies and closes right before or shortly after birth and becomes a solid cord connecting the bladder to the navel
• Certain disorders of the urachus, such as diverticula, umbilical sinuses and cysts can be caused by either developmental defect or by damage

An ectopic ureter is a developmental disorder and can occur in any breed. There is a higher risk for ectopic ureter in the following breeds:

• Fox Terriers
• Labrador Retriever
• Miniature Poodles
• Siberian Huskies
• Toy Poodles 
• West Highland White Terriers

Disorders of the urachus are usually developmental in nature as well, although physical trauma during the time when it should be shrinking down may cause these kinds of disorders. There have even been rare cases of urachal disorders being caused by a separate disorder or illness that happened to put undue pressure on the bladder.

In order to make a diagnosis your veterinarian will ask for a full medical history of the animal, as well as do a general physical exam. This is likely to include a blood count and chemistry profile. The symptoms related to these disorders may also prompt your veterinarian to request a urinalysis to check for bacterial infection and to rule out possibilities such as bladder stones or kidney disorders. Both disorders increase the likelihood of urinary tract infections occurring, and a confirmation that a bacterial infection is present does not rule out a physical defect. 

An abdominal x-ray or dye study will generally be how a final diagnosis is reached. In a dye study, a special contrast dye is introduced into your pet’s system before the x-ray in order to see the path that fluids are taking within the body.

Any underlying conditions will need to be addressed either before or concurrently to correcting the anomaly. Antibiotics may be prescribed to clear up any secondary infections such as urinary tract or bladder infections, and any conditions that may be causing stress to the bladder or pressure on the urachus will be attended to. 

Both ectopic ureter and the urachal disorders generally require surgery to correct. As neither surgery is common in general practice your pet may be referred to a specialist for the surgery. The aim of the surgery for an ectopic ureter is to create a new opening in the bladder, then reroute the ureter into the bladder and suturing it in place. In cases of infection or damage to the kidney, the ureter and connecting kidney may require complete removal. Incontinence may continue after surgery in up to 50% of patients, but usually with reduced frequency. 

With urachal disorders the usual goal of the surgery is to remove the entire remaining structure. This prevents reoccurrence of the disorder, as well as eliminating the possibility of cancer developing on the urachus later. Prognosis after the removal of the urachus is excellent.

When you first bring your pet home it is best to have a comfortable, clean and quiet space for your companion to recuperate with plenty of access to unpolluted food and clean water.

If surgical options were required, you will need to limit your pet’s activity for approximately two weeks as well as ensuring that any incisions are checked for infection. It is also important to monitor your pet’s bathroom behavior as well, confirming that urine is flowing properly. It is common to see small amounts of blood in the urine for the first week or two after surgery. If antibiotics were prescribed for any underlying conditions, make certain that your pet completes the full measure of their antibiotic medication, to help prevent a relapse.