Better known as the Wet Bed Dripping Dog Syndrome
by Margot B. Schwag, VMD
** Permission of author is required for use of this article.**
Let me tell you about my wonderful, now-deceased bitch, Poppy. I was more important to her than life itself; she was my shadow. However, life with Poppy could be a chore due to her urinary incontinence. Luckily her problem was easily treated.
When dogs lose the voluntary control of either storing urine in their bladder, or voiding urine while urinating, they are defined as being urinary incontinent. This occurs as a result of two main disorders:
Disorders due to nerve disease, which include:
the inability of the bladder muscle to contract
the bladder that empties once it reaches a certain level of fullness
abnormal function of the urethra
Disorders not due to nerve disease, which include:
hormone responsive incontinence
stress or urethral incontinence
ectopic ureters, i.e. abnormal connections of the ureters to the bladder.
The bladder is anatomically divided into distinct functional units. The body of the bladder is responsible for storing urine; it is primarily comprised of a muscular layer, i.e. the detrusor muscle, which contracts when needed. The outlet areas are composed of the trigone (exit) region and the initial part of the urethra.
Simply stated, nervous control of the bladder and urethra comes from two divisions of the nervous system – the parasympathetic and the sympathetic. These nerves arise from the areas of the pelvis; when stimulated, the detrusor muscle causes the bladder to empty. The sympathetic division comes from nerves coming from the lower back. It sends messages to the urethra to constrict. Voluntary control of urinating is controlled through the brain and spinal cord. The pudendal nerve controls the external urethral sphincter, comprised of striated muscle which is under voluntary control.
Most dogs having problems controlling urination are over five years of age. Common signs of incontinence include dribbling of urine and /or loss of voluntary control. Common signs of animals having trouble urinating include the inability to urinate, disruption of the urine stream, straining to urinate, and abdominal pain or discomfort.
Diagnosis of urinary incontinence is dependent on: history – age of onset, neutering, previous medical problems, and history of trauma. Is the problem continuous or intermittent, how much urine is produced at a time, is the animal even aware, how often does the pet urinate, do they have accidents at day or at night or both, any presence of blood, pain on urination?
Physical exam: the bladder is palpated before and after urination to determine extent of distention, tone and ease. Disruption of nerves from the brain is associated with difficulty contracting the bladder and increased urethral resistance. Disruption beyond the spinal cord results in easy manual emptying of the bladder and decreased urethral sphincter tone.
Laboratory evaluation: to assess the functioning of the kidneys, i.e. blood urea nitrogen (BUN) and creatinine, urinalysis, and bacterial culture and sensitivity, to look for infection.
Urethral pressure profiles are typically available through veterinary schools. The strength of the bladder contractors, internal and external urethral sphincters can be determined.
Radiology or ultrasongraphy look for skeletal abnormalities in the pelvis, stricture of the urethra, prostatic enlargement, bladder stones, bladder wall thickening, urachal diverticulum (a congenital problem).
Depending on the diagnosis, a cure or management program may be possible. Common diagnosis of dribbling urine includes:
bladder atony – the detrussor muscle is non-functional. As a result the bladder is always overly full; therefore, urine leaks continually. Treatment includes trying the dog on bethanechol and learning to manually empty the bladder of the dog.
hormone-responsive incontinence – these are older, neutered animals, they can urinate normally. However, when relaxed or asleep, they may leak. Treatment includes diethystilbestrol (DES), phenylpropanolamine (PPA), or testosterone.
stress incontinence – these dogs can urinate voluntarily; however, when stressed, they lose voluntary control. Treatment may include PPA or ephedrine.
ectopic ureter(s) – these pets dribble continuously even though they can urinate voluntarily. Treatment consists of surgery or drug trials with PPA.
urge incontinence – as in urine spraying, cystitis (bladder infections), etc.
paradoxical incontinence: due to a blockage of the urethra, the bladder fills with urine – however with enough “back” pressure urine leaks around the urethral structure, cancer, bladder stones, etc.
Urethral sphincter incontinence is the most common form of leaking. Typically treatment includes therapeutic drug trials. If therapeutic trials fail, further diagnoses are employed. DES (diethylstilbestrol) is an oral estrogen preparation. The most common side effect includes bone marrow suppression; however, at the low doses we employ, this is rare. PPA helps to strengthen the smooth muscle that lines the urethra; caution is indicated with dogs who have heart disease. Occasionally, multiple drugs may be used simultaneously.
As mentioned earlier, Poppy suffered from urethral sphincter incontinence (relaxation) – PPA given twice daily kept her under control. However, she would still have accidents on occasion. Poppy’s incontinence continued for her final six years. Yes, it was a challenge; however, the love and happiness she gave me was well worth the inconvenience. Given the choice, I would do it all over again without a second thought.
Reprinted from DOBERMAN DISPATCH, newsletter of Doberman Pinscher Rescue of PA, Inc.
© 1998 Margot B. Schwag, VMD. All rights reserved. For permission to reprint contact author at Landisville Animal Hospital, 3035 Harrisburg Pike, Landisville, PA 17538.