Does my dog have a urinary tract infection?

How To Treat A Urinary Tract Infection In A Dog

It is not uncommon for dogs to have urinary tract infections. It is important to recognize the symptoms of an infection so that appropriate steps can be taken to treat the infection.

What is a UTI?

The urinary tract is made up of a few components: the kidneys are responsible for the production of urine which then travels through small tubes called ureters to be stored in the bladder.  In a healthy cat or dog, no bacteria are found in any segment of the urinary tract. 

A urinary tract infection (commonly referred to as a UTI) refers to the infection of any portion of the urinary tract: that is, either the kidneys or the bladder (cystitis). In the majority of cases, this infection is caused by bacteria but rarely other infectious agents (yeast, etc.) are implicated.


Where do these infections come from and are they contagious?

UTIs almost always occur when bacteria that are normally found in the external genitalia or the hair surrounding this area gain access to the bladder and start to grow within the urine. 

If the infection is more severe, the bacteria may then travel up to the kidneys and cause infection there.  Urinary tract infections are not contagious to other animals or people.


What are the clinical signs of a UTI?

When the infection affects only the bladder, the signs that may occur are: frequent small urinations, foul-smelling urine, straining to urinate and blood in the urine.  Rarely, if only the bladder is infected, will animals show signs in other parts of their bodies.  However, if the kidneys are infected they may have fever, loss of appetite, increased drinking and urination and sometimes even vomiting.


What should I do if my animal shows signs of a UTI?

If your animal shows any of these signs, you should contact your veterinarian as soon as possible.  When you see your veterinarian, they will examine your cat or dog and perform some tests to confirm the presence of an infection. 

The first test that will be done is called a urinalysis. A urine sample is taken and certain values are measured in the urine and the urine is also looked at under a microscope. 

Ideally, this sample is either taken by cystocenthesis (a needle is inserted in the bladder through the belly and urine is taken in much the same way as blood is drawn) or sterile catheterization (a catheter is inserted through the urethra to the bladder and a sample is taken). 

These techniques are used to avoid contaminating the sample with the bacteria found normally in the external genitalia or on the hair.  If obtaining urine in these ways is not possible, a mid-stream free-catch sample may be obtained (as your pet urinates, we catch some urine in a jar halfway through the urination).

Samples that are collected from the floor or on the exam table are almost always contaminated with environmental bacteria and are not ideal.  The presence of an infection is confirmed by detecting bacteria and white blood cells in the urine. 

The second step in the diagnosis of a urinary tract infection is a urine culture and sensitivity.  This test involves sending a small urine sample to the laboratory and putting it on a special medium to grow (culture).  If the bacteria grow, tests will then be run to determine which type of bacteria are present. 

Then, these bacteria are tested against different antibiotics to determine which ones will kill the bacteria. This is called sensitivity testing and allows veterinarians to choose the right antibiotic to treat the infection.

If your pet is showing generalized signs of illness (fever, lack of appetite, etc.) Your veterinarian may also want to run some blood tests. 


How do you treat a UTI?

Most cases of UTI are easily treated with a short course of antibiotics (ideally selected based on sensitivity results). Often, your pet’s clinical signs will resolve rapidly, however, it is always important to complete the course of antibiotics that has been started to avoid recurring infections.

If your animal is very ill, hospitalisation with intravenous antibiotics and fluids may be required. 


Complicated UTIs

When a patient has recurrent infections, your veterinarian may look for underlying causes that predispose to infections. These causes may include: kidney infections, bladder or kidney stones, malformations of the bladder or vagina, prostatic infections, bladder tumors or other diseases such as diabetes mellitus or renal insufficiency. 

At this stage, they may even refer you to a specialist for further investigations (abdominal ultrasound, surgery to correct abnormalities or remove stones, etc.). 

Article written by Dr Lara Rose, veterinarian at Centre Vétérinaire Rive-Sud