TL;DR: If your cat passes a urinary stone, it is a medium urgency requiring a veterinary visit within 24 hours to prevent a life-threatening blockage; however, straining or vomiting requires immediate emergency care.
What are urinary stones in cats and how do they affect my pet?
When a cat passes a stone in their urine, it means that minerals in the bladder have crystallized and clumped together to form a solid mass, known as a urolith. These stones can range from the size of a grain of sand to a large pebble. Passing a stone indicates significant irritation and inflammation within the urinary tract, which can be very painful for your feline companion.
Is passing a urinary stone a medical emergency for my cat?
- The urgency level for a cat that has passed a stone is Medium, as it indicates a high risk for a future life-threatening urinary obstruction.
- Schedule a veterinary appointment within 24 hours to address the underlying cause of the stone formation.
- Treat the situation as a critical emergency and go to an ER immediately if your cat is straining to urinate without producing anything, is lethargic, or is vomiting.
Why should I take a photo of the stone to help with triage?
- If you find the stone, take a clear, close-up photo against a neutral background and bring the physical stone to your veterinarian.
- A photo allows the vet to see the size, color, and texture immediately, providing vital clues about the stone's mineral composition.
- Identification is crucial because different stones, such as struvite or calcium oxalate, require different treatments ranging from special diets to surgical intervention.
Clinical Context (Merck Veterinary Manual)
Feline urolithiasis is a common cause of feline lower urinary tract disease (FLUTD). While smaller uroliths may require double-contrast radiography for detection, radiographic evidence of uroliths is seen in a significant percentage of cats with hematuria or dysuria. The typical approach for observable urocystoliths involves surgical removal or lithotripsy, followed by preventive dietary therapy. Medical dissolution is preferred for sterile struvite uroliths. Calcium oxalate uroliths are the most common type in cats. Ammonium urate, uric acid, calcium phosphate, and cystine uroliths are less common, with highly acidic and concentrated urine potentially being a risk factor for urate urolith formation. If medical treatment fails to completely dissolve uroliths, the mineral composition may be incorrect, the urolith nucleus may differ, or owner compliance may be lacking.
Chapter: Urology
Source: The Merck Veterinary Manual, 11th Edition (Page 1531)