Urinary Tract Infections in Cats

What is a urinary tract infection?

A urinary tract infection (UTI) occurs when the usually sterile urinary tract is colonised by bacteria (or less frequently viruses). The urinary tract is is a system in the body involved in the formation, storage and elimination of urine. It includes two kidneys (which filter and clean the blood, forming urine in the process of removing excess water and waste products), two ureters (which transport urine from the kidneys to the bladder), the bladder (which stores the urine until voiding) and the urethra which transports urine from the bladder to outside.

You may notice the terms urinary tract infection and FLUTD (which stands for feline lower urinary tract disease) used interchangeably. Urinary tract infection is just that, an infection of the urinary tract, FLUTD (formerly known as FUS) is a collection of diseases of the urinary tract, including urinary tract infections.

There is a higher incidence of urinary tract infections in middle-aged to senior cats. The most common types of bacteria to cause urinary tract infections are E. Coli, Staphylococcus spp, Streptococcus spp and Proteus spp.

Clinical signs

The urinary system has several natural barriers in place to prevent infection. Infection can occur when these barriers break down.

  • Bacteria descending from the perineum/anal region are the greatest cause of urinary tract infections in cats. Females are at a higher risk due to their shorter urethra.
  • Cats who hold on to urine for too long are at greater risk. Common reasons for this may include reluctance to urinate outside due to poor weather (snow or rain), dirty litter trays, changing types of cat litter, litter tray in an unfavourable location.
  • Diabetic cats are more prone to developing urinary tract infections. Glucose and protein in the urine, along with a lowered immune response can produce a favourable environment for bacterial growth.
  • Male cats who have had a perineal urethroscopy.
  • Any cat who has been catheterised as this can introduce bacteria into the urinary tract.


Being alert to possible symptoms can mean quick treatment for your cat and greatly reduce distress and litter tray problems. Common symptoms of urinary tract infections include:

  • Frequently visiting the litter tray but only producing small amounts of urine
  • Licking the genitals
  • Urinating outside the litter box
  • Blood in the urine (hematuria)
  • Meowing/crying more than usual, especially when using the litter tray
  • Discomfort when petted

Seek veterinary attention immediately if you notice any of the above symptoms.


The veterinarian will perform a complete medical examination and palpate the bladder to check if it is full and obtain a medical history from you.

Diagnostic workup:

Urinalysis: This may reveal the presence of bacteria, red blood cells, white blood cells and urinary crystals. A sample of urine will be collected by cystocentesis, which involves inserting a fine needle through the abdominal wall and into the bladder. This prevents the sample from becoming contaminated with bacteria.

X-ray or ultrasound: To evaluate the urinary tract for stones or tumours.

Bacterial culture and sensitivity: A diagnostic test to determine which antibiotic will be the most effective against a microorganism. A urine sample is obtained by cystocentesis (to ensure there has been no contamination) and sent to a laboratory where cultured, forming a bacterial lawn. Filter paper that has been impregnated with antimicrobial drugs are placed on the bacterial lawn to determine the most effective antibiotic. E. coli is the most common bacteria to infect the cat’s bladder; other bacteria include Proteus, Staphylococcus, and Streptococcus.


Antibiotics will be prescribed to treat bacterial infection based on bacterial culture results.

Switching your cat from a dry diet to a wet diet (canned or raw), which has a higher water content. This, in turn, increases the amount of water consumed, resulting in less concentrated urine.

A prescription diet to dissolve bladder stones, large stones will need surgical removal.


Encourage frequent urination by offering plenty of clean, fresh drinking water.

Scoop litter trays twice a day, cats can be very fussy and refuse to use a dirty tray.

Be alert to changes in behaviour is extremely important, the quicker you act with urinary tract infections, the better for your cat.


  • Julia Wilson, 'Cat World' Founder

    Julia Wilson is the founder of Cat-World, and has researched and written over 1,000 articles about cats. She is a cat expert with over 20 years of experience writing about a wide range of cat topics, with a special interest in cat health, welfare and preventative care. Julia lives in Sydney with her family, four cats and two dogs. Full author bio

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