Why does my cat have blood in his urine?

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Why does my cat have blood in his urine?

Cystitis, or bladder inflammation, is a common and painful condition in cats that can cause bloody urine. If your cat has ever shown signs of pain when urinating or passed small amounts of urine in odd places around the house, keep reading to learn about diagnosing and treating cystitis.

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Signs of Cystitis in Cats

  • Frequent visits to the litter box
  • Pain while urinating. Your cat might vocalize or squat for extended times*
  • Straining to urinate*
  • Peeing blood
  • Urinating frequently in unusual places (eg on beds, floor)
  • Over-grooming around the genital area (because cystitis causes pain and irritation of these places too)

*VERY IMPORTANT to differentiate this from signs of a blocked bladder! See this article for further information.

Causes of Cystitis in Cats

Unlike humans, cystitis is often not caused by a bacterial infection. Around 60-70% of cystitis in cats is classified as Feline Idiopathic Cystitis or FIC. In these cases, a cause is not determined. However, these cats all suffer from the signs listed above.

Other causes of cystitis or bloody urine include:

  • Bacterial infection. Though less common, older cats that have chronic kidney disease or diabetes are at much higher risk of infection.
  • Bladder stones
  • Bladder growths such as tumors or polyps

If you suspect cystitis, you must seek treatment from a vet as soon as possible. A blocked bladder is a true emergency. While cystitis isn’t quite as life-threatening, it is uncomfortable and in some cases may progress to cause a blockage with a urethral plug.

Diagnosis of Cystitis in Cats

Your vet will examine your cat and should be able to determine the size of the bladder, ruling out a blockage. They will recommend collecting a urine sample to look for signs of infection, stones, or other underlying causes such as diabetes. In older cats, blood tests may be recommended as well.

Further tests can include bladder ultrasound (very sensitive if stones or polyps are suspected), bladder x-rays, and less commonly, bladder biopsy or cystoscopy.

Treatment of Cystitis in Cats

  • Cystitis is always painful, so the number one priority is to administer painkillers. There is a range of options from opioids to anti-inflammatories. Your vet will be the best judge of what’s appropriate.
  • Fluids are sometimes given subcutaneously or intravenously to encourage frequent emptying of the bladder. Also, your vet may recommend additional water in the diet to increase their intake at home (see below for tips on how to increase your cat’s water consumption).
  • Dietary change may be appropriate for some patients to change the pH or reduce the formation of bladder crystals/stones. Some bladder stones can be successfully dissolved with a correct diet.
  • Antibiotics are appropriate only if an infection is suspected.
  • Longer-term medications such as anti-anxiety drugs may be used in persistent cases of FIC.

Prevention of Cystitis in Cats

If an underlying cause is detected, treatment is crucial to preventing recurrence. Unfortunately, FIC can be a recurring problem even if no underlying disease is identified.

Risk factors for FIC include:

  • Middle-aged
  • Overweight
  • Cats that are inactive and exercise very little
  • Reduced water intake
  • A multi-cat household

Prevention of FIC should include a weight control diet and consideration of environmental factors:

  • There should be adequate access to litter boxes, preferably the number of cats in the house +1. These should be situated in accessible areas, if the house is very large, more litter boxes may be necessary.
  • If there is a multi-cat household, any inter-cat aggression/bullying should be identified and minimized. Aggression can be subtle and consulting a behaviorist could be appropriate. Cats are often solitary creatures and prefer somewhere to sleep away from the others. Giving them a safe high perch and a quiet room can help.
  • Using anti-stress pheromones such as Feliway around the house may help. If there is a strong suspicion of stressors that can’t be easily resolved, tricyclic antidepressants may be prescribed. These are not usually a first-line treatment but play a part in reducing the recurrence of long-term FIC.
  • Ensuring an enriched environment (eg scratching posts, toys) and making time to play with your cat can also help.
  • Water Intake is very important. Cats can be encouraged to drink by flavoring the water or providing a water fountain. Adding additional water to the diet is also appropriate.

Read more:

Feline Lower Urinary Tract Disease

Noise Anxiety in Cats and Dogs

Separation Anxiety in Cats

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Published: 12/13/2020
Last updated: 10/31/2021

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