Urinary tract infections (UTIs) in dogs are painful, complex, and potentially dangerous issues occurring in as much as 27 percent of the dog population.
When a housebroken dog starts having accidents around the house, it is a red flag for a urinary tract infection. Straining while urinating, blood speckles in the urine, and licking the genitals are other red flags.
Best-case scenario, urinary tract infections are uncomfortable, and worst-case scenario, if left untreated, are life-threatening.
Dogs suspected of having a urinary tract infection or manifesting changes in standard urinating patterns need to be closely examined by a veterinarian.
What is a Urinary Tract Infection?
Urinary tract infections are an infection affecting parts of the urinary tract, including the kidneys, ureters, bladder and urethra.
In theory, all parts of the urinary tract can get infected, but infections are most likely in the lower portions, namely, the bladder and urethra.
Regular vs. Recurrent UTIs in Dogs
The bladder is like a storage room for urine the kidneys produce. On its own, the bladder is sterile. However, the bladder is closely linked with the external genitals, and they are contaminated with lots of different germs.
If these germs find their way into the bladder and start multiplying, they trigger an infection that results in UTI symptoms.
This is how a simple or regular UTI develops, and most dogs get regular UTIs that can be controlled throughout an antibiotic treatment.
However, if a dog develops more than three UTIs in a year or, alternatively, more than two UTIs in six months, the condition classifies as a recurrent UTI.
Simply put, both the regular and recurring UTIs are the same in terms of causes and symptoms; the only difference is the frequency of occurrence.
Classification of Urinary Tract Infections
While on the subject of explaining the UTI terminology, we should mention that a urinary tract infection can be classified as:
- Relapse, this occurs when the new UTI is caused by the same microorganism as the previous infection.
- Reinfection, this occurs when the new UTI is caused by a different microorganism than the previous infection.
Finally, based on the infectious agent, the UTI can be defined as a:
- Super-infection, this occurs when the new UTI is caused by a resistant bacteria that was acquired during the initial UTI treatment
- Persistent infection, this occurs when the original UTI causing agent persists despite treatment efforts.
Causes of Recurrent Urinary Tract Infections in Dogs
In most cases urinary tract infections occur when bacteria from the gastrointestinal tract (usually E. coli) inhabit the genital area and then start moving up the urethra.
Certain issues and conditions serve as risk factors because they promote bacteria buildup and multiplication. The most common risk factors include:
- Systemic conditions affecting the immune system function like Cushing’s disease, obesity, hypothyroidism, and diabetes
- Stones, polyps, and tumors in the bladder
- Stones or tumors in the kidneys
- Prolonged use of certain medications like steroids or chemotherapy
- Weakened urinary sphincters as a result of old age or spay procedures which leads to persistent urine dripping
- Neurological problems
- Functional or structural abnormalities (urinary or fecal incontinence, recessed vulva, incomplete bladder emptying, vaginal or vestibular urine pooling) which lead to urine drops and moisture getting trapped in the genital area and acting as perfect breeding ground for germs.
Basically, any dog can develop a urinary tract infection. However, females are more likely simply because, in females, bacteria need to make shorter trips to reach the urinary tract structures than in males.
According to the American Kennel Club, certain dog breeds like Yorkshire terriers, Shih Tzus, and Bichon Frises are more likely to develop urinary tract infections.
Perhaps this is due to their tendency of forming urinary tract stones and stones are a risk factor for UTIs.
Signs of Recurrent Urinary Tract Infection in Dogs
Breaking the housetraining habits is the tale-tell sign for urinary problems. More specifically, a dog with a regular or recurrent urinary tract infection will show the following signs and symptoms:
- Urine dripping
- Difficulty urinating (crying, whining)
- Increased urination frequency
- Producing larger amount of urine
- Increased water intake
- Frequent licking of the genital area
- House accidents
- Changes in the urine transparency, color, and smell.
In cases of complicated or advanced urinary tract infection, the dog may exhibit:
- Loss of appetite
- Pronounced tenderness around the genital area.
Diagnosis of Recurrent Urinary Tract Infection in Dogs
As in any other case, the vet will start with a full body examination and take your dog’s history. The vet will probably ask questions like:
- When did you first notice changes in your dog’s urinating patterns?
- What are the exact urinary patterns you noticed?
- Are there other accompanying symptoms?
- Does your dog have any underlying or chronic issues?
- Is your dog receiving any new drugs or supplements?
Then, based on the initial findings, the vet will proceed with some more specific diagnostic tests and procedures. Following are several diagnostic procedures for diagnosing urinary tract infections.
When the vet suspects a UTI the first diagnostic procedure is urinalysis. A simple urinalysis can reveal helpful information. The vet will pay special attention to the following parameters:
- pH – changes in the urine pH are indicative of infections
- Urine specific gravity – provides an insight into the kidneys’ ability to concentrate urine
- Glucose – the presence of sugar in the urine indicates diabetes
- Ketones – can be seen in dogs with diabetes
- Bilirubin – a blood breakdown product
- Blood cells – means there are micro-injuries on the urinary tract lining.
The urine sample can also be examined under a microscope. Bacteria, debris, crystals, and blood cells can easily be visualized with this procedure.
Urine culture not only proves the presence of a urinary tract infection, but also reveals the type of germ that causes the infection. Identifying the exact infection culprit makes it possible to prescribe a more targeted treatment.
Abdominal Ultrasound and X-Ray Imaging
Both techniques are helpful for evaluating the overall bladder and kidney health. They can be used to diagnose stones, crystals, polyps, and tumors.
In cases of bladder infection, the ultrasound test will show thickening of the bladder lining.
Cystoscopy is recommended when the vet suspects the underlying issue is located in the vagina, urethra, or bladder.
The procedure is performed under general anesthesia and involves inserting a small camera inside the urinary tract.
Treatment of Recurrent Urinary Tract Infections in Dogs
The treatment of UTIs in dogs has two goals: addressing the underlying cause as the exact approach depends on the primary issue, and addressing the infection which involves long-term antibiotics (between four and eight weeks based on the case).
To evaluate the improvement and antibiotic treatment’s efficacy, dogs with UTIs need regular urine re-culturing. This is the standard urine re-culture protocol:
- Between 5 and 7 days of the antibiotic therapy initiation
- 3 days before discontinuing the antibiotic therapy
- Between 7 and 14 days after the discontinuation of antibiotics.
Recurrent urinary tract infections are a predisposing factor for bladder stones and dangerous kidney infections. Therefore, dogs with UTIs histories need to have urine culture evaluations every three months regardless of whether they are showing any UTI symptoms.
Could It Be Something More Than a Recurrent UTI?
A dog that shows signs of recurrent urinary tract infections on a regular basis needs to be thoroughly examined for canine bladder cancer.
The most common type of canine bladder cancer is transitional cell carcinoma (TCC), an invasive and life-threatening condition.
TCC is particularly common among certain dog breeds – Scottish terriers, Beagles, West Highland white terriers, Shetland Sheepdogs, and Wire Hair Fox terriers.
The diagnostic procedures are expensive and invasive and include urine cytology, abdominal ultrasound examinations, and cystoscopy. These procedures take time, and because of the tumor’s invasive nature, cancer would have grown substantially by the time the results are available.
If the TCC has not spread beyond the bladder, surgical tumor removal is possible. In the case of spreading, radiation and chemotherapy are options, but they are associated with considerable side effects.
Preventing Recurrent Urinary Tract Infections
There are several ways of preventing urinary tract infections in dogs, including:
- Providing fresh drinking water – a dog that drinks copious amounts of water is less likely to develop a UTI because it will urinate more frequently thus flushing the urinary tract.
- Make sure your dog makes frequent potty breaks – dogs that do not eliminate urine regularly have a higher risk of developing a UTI.
- Supplement your dog with probiotics to ensure and encourage healthy bacteria growth.
- Keep the genital area clean – it is important to maintain the urinary opening free from debris. This can be achieved with antibacterial wipes formulated for pets. In dogs with long coats that tangle in the anal area, trimming the coat short can improve the overall hygiene level.
- Have your dog’s anatomical or functional abnormality surgically corrected – in dogs with congenital abnormalities that can be fixed (for example, excessive folds around the vulva) the sooner the correction is made the lesser chances of developing a UTI.
- Cranberry extract – many holistic vets recommend using cranberry extracts to treat and prevent urinary tract infections in dogs. However, scientific data proving the cranberry’s beneficial effect on this condition is scarce and most positive reports are anecdotal.