TL;DR: Blood clots in a cat's urine indicate significant urinary tract inflammation and require a veterinary exam within 24 hours; however, if your cat cannot pass any urine, it is a life-threatening emergency.
What does it mean if my cat is passing blood clots in their urine?
Seeing blood or visible clots in your cat's urine, medically known as hematuria, indicates significant inflammation or trauma within the urinary tract. When bleeding is heavy enough, the blood can gelatinize into clots. This is often associated with Feline Lower Urinary Tract Disease (FLUTD), bladder stones, or severe bacterial infections that irritate the bladder lining.
Is seeing blood clots in my cat's urine a veterinary emergency?
- Medium Urgency: Most cases of hematuria require a veterinary examination within 24 hours due to significant pain and internal irritation.
- Critical Emergency: If your cat is straining and unable to pass any urine at all, this indicates a life-threatening blockage requiring immediate medical attention.
Why should I take a photo of the blood clots for my veterinarian?
- Take a clear photo of the urine and blood clots in the litter box or on the floor.
- Document the size, color, and frequency of these clots to provide objective evidence of the bleeding's severity.
- Provide the photo to the clinical team to help them decide how quickly your cat needs to be seen for diagnostic imaging or urinalysis.
Clinical Context (Merck Veterinary Manual)
In cats, passing blood clots in urine (hematuria) can be a sign of feline lower urinary tract disease (FLUTD), with underlying causes including urinary tract infection, neoplasia, trauma, urethral plugs, urolithiasis, or sterile cystitis. Urolithiasis, involving calcium oxalate, magnesium ammonium phosphate, or urate stones, is often suspected based on hematuria, dysuria, or urethral obstruction. Urinalysis, urine culture, radiography, and ultrasonography are required to differentiate uroliths from urinary tract infection or neoplasia. Radiography, cystoscopy, or ultrasonography are critically important to detect uroliths, as abdominal palpation alone is insufficient.
Chapter: Urology, Emergency
Source: The Merck Veterinary Manual, 11th Edition (Page 1527)