Signs & Symptoms of a Bladder Infection in a Dog

By Rebecca Bragg

Though bladder infections are common in dogs, most are cleared up with a course of prescribed antibiotics. But symptoms of several other serious urinary tract problems closely resemble those of bladder infections, especially in the early stages. That's why it's important for dog owners to familiarize themselves with characteristic signs of trouble and always have your dog checked out by a vet. Sudden onset of symptoms of acute distress should be considered a medical emergency.

The Canine Urinary Tract

Human and canine urinary systems function in much the same way. After urine is produced in the kidneys, it flows down tubes called ureters into the bladder. This organ near the back of a dog's abdomen is capable of expanding like a balloon. The fuller a dog's bladder gets, the more urgently he feels the need to empty it. Healthy urine, which is sterile, leaves the body through a tube called the urethra, but harmful bacteria from the outside can use the urethra as an doorway into the body. From there, it travels up to the bladder, causing infection to set in. In female dogs, the urethra is closer to the microbe-laden rectal and genital areas than in males, making them more susceptible to these bladder infections.

Cystitis: One Term But Many Causes

Cystitis is a catch-all term for bladder inflammation. Infection is the most common of all possible causes but others include sharp-edged bladder stones, injuries, malignant or benign growths, prostate disease in males, even congenital abnormalities. Adrenal disease and diabetes also increase the risk that a dog will develop bladder infections, as do medications such as corticosteroids, which depress the body's immune system, and antibiotics. As dogs age, they become increasingly susceptible to cystitis. According to VCA Animal Hospitals, "sterile cystitis" can cause the same symptoms as an infection even though no infection is present.

Symptoms Your Vet Should Check Out

Inflammation of the walls of the bladder triggers the urge to urinate even if little or no liquid has accumulated. Consequently, the most common indication that something is not right is seeing your dog frequently squatting and straining to urinate without much coming out. When urine is produced by a dog with an infected bladder, it's often tinged with blood, or cloudy rather than clear and has a strong odor. Other warning signs include losing bladder control in the house, dribbling urine, constant licking of the urethra, increased thirst and lethargy. If you notice such symptoms in your dog, call your vet and reserve the first available appointment.

Symptoms Indicating Medical Emergency

Left untreated, bladder and urinary tract infections can become life-threatening. If your dog is feverish and has a swollen, tender abdomen, or is crying and whimpering in pain and unable to pass urine, seek emergency medical help immediately, advises the American Society for the Prevention of Cruelty to Animals. If a bladder infection spreads to the kidneys, those organs, essential for life, can shut down. Bladder stones are a double threat because they can cause infections and vice versa. If stones block urine from being expelled from the body, the bladder can overfill to the point of rupture. One way or another, blockages must be cleared.

Diagnosis and Treatment

The course of treatment your vet recommends will depend upon the nature and severity of the problem. If she diagnoses a straightforward bladder infection based on examination and urinalysis, the standard treatment is a one or two-week course of antibiotics, says Vetstreet, perhaps longer for chronic or severe cases. If she suspects bladder stones, tumors or other abnormalities, she'll likely want X-rays or ultrasound images of your dog's abdomen. If the situation has become life-threatening by the time she sees your dog, immediate surgery to remove any blockage might be the only option. However, if time permits, a nonsurgical procedure using sound waves to pulverize the stones may be a better choice but might require a referral to a specialist. Prescription diets that dissolve stones take much longer and don't always work, Vetstreet says.