Urinary incontinence is a common problem in dogs and a less common problem in cats.
Workup for urinary incontinence begins with a thorough physical examination followed by routine screening laboratory tests: Complete Blood Count (CBC), Chemistry Profile and chemical and microscopic urinalysis.
In the CBC we will be looking for anemia which might be driven by poor bone marrow stimulation from the kidneys, as well as an elevated white blood cell count that might indicate infection in the body. For example, female dogs and cats with infection in the uterus called pyometra frequently drink excessive amounts of water and thus urinate large volumes. Pyometra patients often have WBC counts five times normal.
The Chemistry Profile can identify liver and kidney problems that could cause excessive thirst which could overfill the bladder, predisposing it to simple pressure leakage. Elevation of the enzyme Alkaline Phosphatase might indicate liver disease or could be a marker for Cushing’s Disease, which is also a common cause of excessive thirst and urination. If measurements related to the filtering ability of the kidneys, especially Blood Urea Nitrogen (BUN), Creatinine and Phosphorous are elevated, then the kidneys are implicated in the problem.
The chemical portion of the urinalysis will be important in elucidating Specific Gravity (SG). A SG below 1.015 indicates kidneys that have lost their ability to concentrate urine. Low SG indicates problems in the tubules of the kidneys. Kidney leakage indicators such as protein and glucose show us whether the kidneys have had damage that might keep them from retaining valuable ingredients in the urine that should have been returned to the bloodstream. Elevation of leakage indicators demonstrates damage in the glomeruli of the kidneys.
The chemical portion of the U/A will also detect the presence of red blood cells. Their presence can be confirmed on the microscopic portion of the U/A, along with the presence of white blood cells (WBCs) which indicate an inflammatory process such as interstitial cystitis, crystals, stones or infection.
If infection evidence is found on the microscope, a portion of the urine sample may be submitted to a laboratory for urine bacterial culture and sensitivity.
If infections are identified and treated successfully, the incontinence may be resolved.
If a cause is found for excessive thirst and urination, the underlying problem requires treatment.
On the other hand. if all of these parameters are found to be normal, the incontinent dog or cat may need medication to increase the strength of the urinary bladder sphincters. Most commonly we use the stimulant medication phenylpropanolamine in the form of brand name Proin. Proin comes in chewable tablets and liquid and is administered twice daily for life.
A small percentage of patients may fail to respond to Proin treatment and will need to supplement Proin with a hormone, diethylstilbesterol.For those incontinent patients whose problem is still not resolved there are surgical means of improving incontinence, though these require the skill and training of a board-certified surgeon.
Urinary incontinence can be a smelly and messy problem, but rarely is treatment unsuccessful.