Welcome to the “Health and Welfare”segment of the Newsletter. NEW TREATMENT FOR URINARY INCONTINENCE

AKC Canine Health Foundation (CHF)

Author: Sharon M. Albright, DVM, CCRT

Urinary incontinence is a troubling problem that occurs in more than 20% of spayed female dogs. When the urethral sphincter muscles don’t work properly, the result is uncontrolled urine loss and additional complications such as bladder infections and skin irritation. Standard treatment involves oral medications to help strengthen the sphincter, but not all dogs respond, some dogs have intolerable side effects, and the response can decline over time.

Therefore, the search for additional and more advanced treatment options continues. Urethral injection with bulking agents or surgery to alter the shape of the urethra have been studied, but they also come with potential complications and incomplete response. With funding from AKC Canine Health Foundation (CHF), investigators at North Carolina State University College of Veterinary Medicine explored regenerative medicine as a treatment option for urinary incontinence. Regenerative medicine stimulates the body’s own repair mechanisms to heal tissues or organs. Dr. Vaden, the study’s Principal Investigator, has had success restoring urethral function in a laboratory model after injecting skeletal muscle stem cells. It is believed that injecting stem cells results in a complex process that regrows and replaces nerve and muscle cells. The goal of this clinical trial was to see if the treatment worked in dogs with naturally occurring urinary incontinence that did not respond to standard medical management. Results were recently published in the Journal of Veterinary Internal Medicine.1

REGENERATIVE MEDICINE IS AN OPTION TO TREAT URINARY INCONTINENCE IN FEMALE DOGS.

Fifteen dogs of eleven different breeds and mixes completed the clinical trial. A muscle biopsy was taken from their triceps muscle and processed in the laboratory to provide a large population of muscle stem cells. A second surgical procedure was then completed to inject these stem cells into the tissue surrounding the urethral sphincter. Dogs were allowed to continue their oral incontinence medications for three months after the procedure, but then medications were stopped to see if the dogs would be continent without them. Response was based on owner questionnaires and objective measurement of urethral pressure. According to owner questionnaires, urinary continence improved to mostly or always continent in 14 of the 15 dogs. The effect seems to be long-lasting as 11 of the dogs were still continent two years after the procedure. The stem cell treatment was not curative though, as 13 dogs still required oral medications to be continent. Urethral pressure measurements did not show a significant change, but the measurement is technically challenging and not all dogs returned for measurements at the requested times.This study shows that regenerative medicine is an option to treat urinary incontinence in female dogs. While the procedure was labor-intensive and not curative, there were few complications in the dogs that participated in this clinical trial and most of them did improve. Urinary incontinence has a significant impact on quality of life for affected dogs and their owners.

Therefore, CHF and its donors remain committed to finding new and more effective treatments.

by Elaine Waldorf Gewirtz https://www.akc.org/expertadvice/health/incontinence-in-dogs/

If you diligently housetrained your dog and it has been consistently doing its business in the yard at proper times, it should be noted that incontinence is not a housetraining issue. Even if you missed a few steps in potty training or the process took longer than you anticipated, “forgetting’ potty training likely isn’t the culprit.

A housetrained puppy who suddenly leaves wet messes indoors could suffer from a medical disease, such as Addison’s disease or leptospirosis‚ a contagious disease transmitted by drinking from a contaminated puddle.

The dog who leaves a bathroom boo-boo isn’t purposely misbehaving, either. Feeling anxious over a change in the family or the environment, such as a big move or a divorce, can trigger inappropriate elimination. Although owners of older dogs often blame a puddle problem on their dog’s age, the years alone often aren’t the sole reason. There’s usually an underlying issue, such as dementia or cognitive dysfunction syndrome, which explains why a senior dog forgets where to pee.

Urethral muscles in older dogs are weaker than they once were. As a result, when dogs age, they struggle with holding their urine. That’s why incontinence often begins when dogs reach middle age and their bladder weakens. Some causes of incontinence include:

• Steroids

• Excessive water intake due to diabetes, kidney disease, and Cushing’s disease

• Urinary tract infection

• Hormonal imbalance

• Abnormal anatomy

• Prostate disorder

• Urinary stones

• Weak bladder

One household accident may not mean your dog suffers from incontinence, but several cleanups may signal a trip to the veterinarian is necessary for a checkup. Another sign of this condition comes with your dog dripping urine or you notice irritation on the skin near where they urinate. When a dog continually licks its penis or vulva, it could also be a sign.

To help your veterinarian review your dog’s history and formulate a treatment plan for this issue, provide them with as much information as possible. Keeping notes of when and where your dog urinates in the house and when you first notice the accidents will offer a complete picture of your dog’s condition. Also, note if your dog is drinking more water than average and if the urination seems painful.

Because males and females urinate differently, their incontinence looks a little different as well. Owners often report that their older spayed females will sometimes unexpectedly leak urine while asleep. This situation is caused by dogs’s lower estrogen levels as they age, which weakens their urethral muscles. However, this hormone-responsive incontinence can occur in both sexes.

A weak bladder or Urethral Sphincter Mechanism Incompetence (USMI) is often responsible for incontinence in spayed females. Genetics and obesity could also contribute to the issue.

Your veterinarian will want to perform a urinalysis and blood tests to rule out other medical issues to diagnose incontinence, including a bladder infection or another underlying condition, such as diabetes or Cushing’s disease. They might also perform an ultrasound will reveal if tumors or growths in the bladder are causing the problem. To see if

Micturition depends on the coordinated action between the sympathetic, parasympathetic and somatic nervous systems and central control centers. Urinary incontinence is the involuntary action that results in urine leakage. It is important to speak to your veterinarian if your pet has exhibited urinary accidents in the house because a variety of differentials could be the cause of these clinical signs.

urinary stones are causing the problem, your vet may take radiographs as well.

The notes you’ve taken about your dog’s accidents will help your veterinarian formulate a diagnosis and treatment plan. Once incontinence is confirmed, you can manage the condition by doing a few things.

If your dog tolerates wearing doggy diapers or belly bands indoors, these might save you some serious cleanup. Providing mental stimulation with exercise, interactive toys, and taking your dog on frequent outings may relieve their urge to urinate indoors. You can also try using waterproof pads or washable bedding while they sleep. Some supplements may also help.

Your veterinarian may prescribe a medication for an incontinent hormonal issue. Other drugs are available to improve urethral tone but note that these often come with side effects in dogs, such as restlessness, anxiety, and hypertension.

Above all, maintain your dog’s hygiene to avoid skin infections.!

Ectopic ureters (EUs) are the most common cause of urinary incontinence in young dogs. An ectopic ureter is defined as a ureteral opening in any area other than the normal position in the trigone of the bladder. UI is the most common clinical sign in dogs with EUs and is usually diagnosed in dogs prior to one year of age; however EUs should be considered in any dog with UI, particularly when the history is unknown. continued on next page...

Breeds reported to be at risk include the Golden Retriever, Labrador Retriever, Siberian Husky, Newfoundland and English Bulldog. Although unilateral EUs have been reported to be more common, bilateral EUs were significantly more common in a recent study, which suggests that careful imaging of the urinary tract should be performed prior to surgery in order to obtain the best clinical outcome. EUs are uncommon in male dogs and these animals are often asymptomatic.

A diagnosis of EUs can be made by excretory urography, fluoroscopic urethrography or urerterography, abdominal ultrasound, cystoscopy, helical computed tomography (CT) or a combination of these diagnostic procedures. The latter two appear to be the diagnostics of choice based on two recent studies. Cystoscopy is a minimally invasive tool that allows easy access to the lower urinary tract and visualization of the abnormality. If necessary, contrast can be injected through the scope to provide further imaging studies. Urine cultures should always be performed in dogs with suspected EUs because urinary tract infections appear to be quite common with this disorder.

What are the treatment options for dogs with ectopic ureters?

The standard treatment for dogs with ureteral ectopia is surgical correction, but reported success rates vary between 50-75% after surgery. The poor success rate could be due to a variety of causes including a disease we call urethral sphincter mechanism incompetence (USMI-a urethra that does not have enough tone to keep the urine from leaking involuntarily). Newer therapies for EUs include treating them with a minimally invasive technique which involves the use of a laser. Although this technique has only been performed in a few animals, results are promising and recovery is very quick. To inquire more about therapeutic options for ectopic ureters, feel free to contact the small animal clinic.

URETHRAL CLOSURE PRESSURE

Decreased urethral closure pressure can occur due to lumbosacral disorders such as intervertebral disc diseases and other neurologic problems. A thorough neurologic examination should be performed on all patients who present for UI. Urethral Sphincter Mechanism Incompetence (USMI) (acquired urinary incontinence, mostly after spaying) is a diagnosis of exclusion once all other disorders have been ruled out. UI can be daily or episodic and range from mild to very severe. There appears to be a higher risk for larger breed dogs after spaying compared to small breeds.

The diagnosis of USMI can most often be made based on signalment, history and lack of any other cause of UI found on physical examination. However, urodynamics can be a useful test for animals that present with micturition disorders and these procedures are becoming more standardized in veterinary medicine. We use the Urovision Janus V system by Life Tech® to perform these minimally invasive diagnostics. A urethral pressure profile (UPP) is the diagnostic gold standard for USMI and is also helpful for evaluating urethral tone in dogs with ectopic ureters. To do this procedure, a small catheter is placed in the bladder while the dog

(or cat) is awake or lightly sedated. The catheter is removed at a constant rate while warm sterile water is infused.

The pressure generated in the urethra is captured by pressure transducers connected to the catheter. The entire procedure takes no more than 15-30 minutes.

A cystometrogram (CMG) may also be indicated to see if the bladder is contracting appropriately and at the correct time. A CMG is the gold standard for diagnosing detrusor overactivity (spastic bladder). A urine culture as well as bladder imaging studies should be done prior to the study to be certain the urine is sterile and no obvious urinary calculi or mass lesions could account for the clinical signs. To do this procedure, it can be done just prior to a UPP. The catheter is inserted into the bladder and the bladder is slowly distended with warm sterile water. The pressures and volume infused are recorded and analyzed.

Both of these urodynamic tests should be considered in dogs with refractory USMI, ectopic ureters or abnormal micturition patterns.

Medical management of USMI includes the use of drugs aimed at improving urethral tone via the alpha-1 adrenoceptors ( 1-ARs). Phenylpropanolamine (PPA) is currently the drug that results in continence in the most dogs. Side effects in dogs include restlessness, anxiety, hypertension and tachycardia. This class of drugs is not recommended in patients with cardiac disease or hypertension.

Estrogens may also be used for USMI and these hormones are thought to sensitize the 1-AR to the norepinephrine and indirectly result in an improvement in the closure pressure. The lowest possible dose of estrogen should be used. Diethylstilbestrol (DES) is still the most commonly prescribed form of estrogen for this disease. Bone marrow suppression has been described in dogs receiving older generation depot estrogens and in those receiving very high doses of DES. If the patient is still experiencing UI while receiving an 1-AR agonist, estrogen can be given concurrently.

Submucosal urethral collagen injections are now available for animals that are refractory to medications or for owners who do not wish to continually medicate their pet. Patients are placed under general anesthesia and three to four collagen deposits are injected in a circular fashion approximately 1.5 cm distal to the trigone via the cystoscope. The collagen acts as a bulking agent to create a 'mechanical' urethral obstruction and improve incontinence. Some dogs still require medications after this procedure, but greater continence is usually gained following the implants when drugs were previously ineffective. A second series of implants may be needed to improve continence in some dogs. Twentyseven of 40 (68%) dogs of a recent study were continent for a mean 17 months (1-64 months range). Some dogs with initial full continence deteriorate after 1 year. Retreatment with collagen is usually easier and often successful in gaining continence in these dogs.

Other therapeutic options may be available for your pet with USMI. Please consult with your veterinarian. Other types of urinary incontinence can occur; if you are concerned about your pets urinary habits, please consult with your veterinarian.

https://www.vetmed.ucdavis.edu/hospital/animal-health-topics/canineincontinence

Carl & Candy Holder candachs@aol.com

Breeders: Penelope Neil, Lorraine & David Simmons