Urinary Tract Infection, Lower (Bacterial) in Dogs

Bacterial Infection of Bladder and/or Urethra in Dogs

The invasion and colonization of bacteria in the urinary bladder and/or the upper portion of the urethra may result in infection when the local defense system, which helps protect against infection, is impaired. Symptoms related to this type of infection include inflammation of the affected tissue and urinary difficulties.

Dogs of all ages can be affected, but vulnerability increases with advancing age. In such cases, stone formation, prostate disease, and tumors are frequently seen. Additionally, female dogs are more susceptible to bacterial infections of the lower urinary tract than males.

Symptoms and Types

Some dogs with bacterial infections of the lower urinary tract may not show any signs, but many more do. A few of the more common signs include:

• Difficulty urinating
• Blood in urine (hematuria)
• Cloudy or malodorous urine
• Frequent urination, but only in small amounts
• Urinary incontinence, especially during confinement or at places that are not customary (i.e., locations he has not peed before)
• Urination when bladder is touched (occasional)

Causes

E. coli, Staphylococcus, and Proteus spp. account for more than half of all cases of bacterial infections of the lower urinary tract. Less common bacteria include Streptococcus, Klebsiella, Enterobacter, Pseudomonas, and Corynebacterium spp.

Diagnosis

You will need to give a thorough history of your dog’s health, including the onset and nature of the symptoms, to your veterinarian. He or she will then perform a complete physical examination as well a biochemistry profile, urinalysis, and complete blood count (CBC). Although the results of the CBC and biochemistry profile are often normal, urinalysis findings will provide valuable information for initial diagnosis. For instance, pus, blood, or proteins are often seen in the urine. The urine sample, which is taken from the bladder with a syringe, is then cultured to grow the causative bacteria (allowing for sensitivity testing).

Once the bacteria is identified, your veterinarian will recommend suitable antibiotics for treatment. X-rays and ultrasonography of the lower urinary tract may also reveal the presence of stone or other abnormal lesion.