UTI in Dogs: Signs, Causes, and When To Call Your Vet

What Are UTIs in Dogs?

A urinary tract infection (UTI) in dogs is a common problem in veterinary medicine, with about 14% of dogs being affected.

UTIs are often caused by bacteria that are typically found in or around the rectum, skin, or hair near the external urethral opening traveling through the urethra into the bladder.

Less commonly, they can be spread through the bloodstream. Viral and fungal diseases can also cause UTIs in dogs, but they are less common.

A UTI in dogs causes pain and swelling of the bladder, leading to symptoms like painful or bloody urination.

Types of UTIs in Dogs

UTIs in dogs can be either:

1. Simple or uncomplicated (sporadic cystitis): No predisposing factors or other diseases present; less than three UTIs in the past 12 months

2. Complicated or recurrent: Seen in pets with underlying medical conditions or predisposing causes; pets who have had recent antibiotic usage; pets with more than three UTIs in the past 12 months.

UTIs in dogs are a veterinary emergency.

If left untreated, they can cause life-threatening complications including pyelonephritis (kidney infection), sepsis, and kidney failure.

Symptoms of UTIs in Dogs

Symptoms of UTIs in dogs include:

• Straining to urinate (stranguria)

• Painful urination (dysuria)

• Passage of small amounts of urine, sometimes seen as dribbling

• Frequent urination

• Urinary accidents

• Licking genital region or inflammation (swelling) of the genital region, sometimes with salivary staining (copper coloring to the fur from spit)

• Bloody urination

• Genital discharge

• Increased odor of urine

• Increased thirst

Left untreated or in severe cases, more symptoms can occur. These include:

• Lethargy

• Fever

• Decreased appetite

Causes of UTIs in Dogs

Most UTIs in dogs are caused by bacteria usually found on the skin or rectum and moving up the external urethral opening.

Viral and fungal causes are less common.

The most common bacteria to cause infections include:

• E. coli

• Staphylococcus

• Streptococcus

• Enterococcus

• Enterobacter

• Proteus spp.

Females get UTIs more often than males, but any age and breed can be affected.

Middle-aged to older dogs, immunocompromised dogs, and dogs with certain comorbidities (Cushing’s disease, diabetes mellitus, kidney disease) are at higher risk.

Certain breeds are more prone to developing crystals and bladder stones are at a higher risk of developing UTIs.

These include:  

• Schnauzers

• Dalmatians

• Yorkshire Terrier

• Shih Tzu

• Poodles

Other causes for UTIs in dogs can be secondary conditions, such as:

• Neurologic disease such as IVDD, paralysis, or brain or spinal cord trauma

• Urinary incontinence

• Ectopic ureters (congenital condition present at birth), more commonly seen in retrievers and Entlebucher Mountain Dogs

• Hooded vulvas in females

• Bladder cancer, often seen in the Scottish Terrier breed

• Polyps

How Veterinarians Diagnose UTIs in Dogs

To diagnose UTIs in dogs, vets will:

• Perform a thorough physical examination

• Check a dog’s urinary tract and genitalia looking for physical signs of disease or inflammation

• Palpate (touch) the abdomen to check if the bladder is painful

• Possibly perform a rectal exam to palpate the distal urethra and prostate in male dogs

• Perform a musculoskeletal and neurologic exam to check for neurologic conditions that make it challenging for a dog to urinate properly, or signs of arthritis that could affect how a dog urinates

Then, your veterinarian will likely recommend a urinalysis to have a sample of your dog’s urine tested for evidence of infection.

It’s best to analyze the urine within 30 minutes of collection.

The best method for getting the sample is in the hospital through a cystocentesis procedure, where a needle is put into the bladder to take out urine.

This method avoids contamination from the rest of the urogenital tract and is the best method to use before sending out a urine culture, which is the best way to diagnose a UTI.

The urine sample is often sent to a reference laboratory, where it is plated and analyzed for bacterial growth, then analyzed specifically for the type of bacteria present  (i.e., E. coli, Staphylococcus). Then, it is tested against multiple antibiotics to see which is best to use for treatment.

Blood work may be recommended, especially for pets with other health conditions or older dogs.

Imaging such as radiographs, ultrasound, or even cystoscopy (scoping of the urinary tract) may be needed when symptoms don’t stop quickly, if they return, or if the UTI is considered to be a complicated case.

In advanced or refractory cases, biopsy of the bladder may be done, and, in males, a prostatic wash or prostate cytology may be recommended.

Treatment of UTIs in Dogs

If your dog has a simple or first-time UTI, broad-spectrum antibiotics like amoxicillin, Clavamox®, or TMS (trimethoprim/sulfamethoxazole) are typically prescribed for several days.

If the case is complicated, antibiotic treatment is extended out for several weeks while the underlying or predisposing cause is also treated.

If the UTI is complicated by the presence of bladder stones or crystals, treatment for UTIs in dogs could include surgery or a dissolution diet (such as Royal Canin® s/o or Hill’s® s/d), which helps the body dissolve certain kinds of bladder stones or crystals.

Surgery or chemotherapy may be needed to remove a polyp or cancerous mass or to correct an ectopic ureter. For dogs with underlying health conditions such as diabetes mellitus or Cushing’s, treatment of the UTI may also include better management of these diseases.

Your veterinarian may also prescribe pain medications such as gabapentin, tramadol, or a NSAID like Rimadyl® to help manage the discomfort and inflammation caused by a UTI.

Recovery and Management of UTIs in Dogs

Symptoms often start to get better after a few doses of the right antibiotic.

Even if your dog’s condition has improved, it’s important to finish the entire course of the prescribed antibiotic treatment. It may be recommended to recheck your dog’s urine after a few weeks to make sure the infection is gone.

Dogs rarely need hospitalization for this condition.

For dogs with complicated UTIs, your veterinarian may recommend repeating the urine culture during treatment, as well as a week or two after finishing the antibiotics, to make sure the infection is gone.

A diet change may have also been recommended for your pup, in which case it is very important to stick to this new diet after a gradual transition period.

Also, if you encourage drinking and increase your dog’s water intake, she will likely urinate more, which lowers the chances for crystals to stay and grow into stones.

Canned prescription diets can be helpful as they contain more water.

Prevention of UTIs in Dogs

Unfortunately, not all causes of a UTI can be prevented. There are, however, a few recommendations that can decrease the risk of your dog developing one.

For male dogs, proper grooming of the preputial hair can reduce skin bacteria; the same is true for keeping the vulvar region in females cleaned.

Females that are overweight or have hooded vulvas are prone to UTIs, so pet wipes (such as these grooming wipes) are a quick and handy tool that can be used to clean her after urination.

Speak to your veterinarian about the benefits of surgery to correct the hooded vulva and decrease her chance of getting a UTI.

Keeping track of how much your dog drinks, how often he pees, what it looks like (color and odor and stream quality), and his posture can help you get veterinary care quickly if something changes.

Give your dog free access to water with frequent potty breaks. A water fountain may make him want to drink more.

If your pet is older, immunocompromised, or has an underlying disease, it’s important to have his urine checked regularly. Urine strips can be great for checking your dog’s urine at home and, if used over time, can show patterns in your dog’s health.

For dogs with an underlying disease, be sure to keep follow-up and recheck appointments as recommended so his condition can be managed as well as possible.