Researchers from the Royal Veterinary College (RVC) have discovered which cat breeds are at a higher risk of developing kidney and ureter stones.
Namely, these were Burmese, Persian, Ragdoll and Tonkinese breeds.
The research is the first of its kind to examine all cats with upper urinary tract uroliths (stones) as one group and hopes to support vets with diagnostic and treatment plans.
The frequency of diagnosis of upper urinary tract uroliths in cats has been increasing in the last two decades, with 4.6 percent of the cats referred to the RVC’s Queen Mother Hospital for Animals over a 10-year period with upper urinary tract uroliths.
The last similar estimate in the USA was in 1999, when just 0.68 percent in cats seen at veterinary teaching hospitals were diagnosed with upper urinary tract uroliths.
There is a lack of studies examining the frequency of upper urinary tract uroliths in cats in the UK.
Therefore, the RVC’s VetCompass Programme set out to conduct the first study examining all cats with upper urinary tract uroliths.
The research team performed an observational cross-sectional cohort study of all the cats seen as referral patients at the Queen Mother Hospital for Animals over a 10 year period.
The team examined 11,431 cats that had been assessed using abdominal imaging such as ultrasound, x-ray and CT scans and identified 521 cats with evidence of upper urinary tract uroliths.
The study found five cat breeds that were at increased risk of a diagnosis of upper urinary tract stones compared to non-purebred cats. These were British Shorthair, Burmese, Persian, Ragdoll and Tonkinese.
However, non-purebred cats (most frequently Domestic Shorthair) still numerically make up the majority of the felines seen with this condition.
This is also the first study to show that the younger a cat is when diagnosed with kidney stones, the higher the risk of it developing a ureteral obstruction.
The other key outcomes were:
- Risk factors for a diagnosis of upper urinary tract uroliths are: female (versus male); British shorthair, Burmese, Persian, Ragdoll or Tonkinese (versus non-purebred cats); and 4 or above years of age
- Cats aged 4 to 8 years have the highest risk of being diagnosed with upper urinary tract uroliths
- Risk factors for cats with these uroliths developing ureteral obstruction (potentially life-threatening) are: female, having uroliths in both kidneys and a younger age
The findings of the study help inform the veterinary profession about the increased risk for upper urinary tract stones in younger cats.
It also highlights that patients presenting with azotaemia (increased kidney markers) under 12 years of age should have upper urinary tract uroliths considered as an underlying cause of their condition.
The study shows the younger a cat is at diagnosis of kidney stones, the more likely it is to develop ureteral obstruction.
Therefore, cats that are presenting as unwell with a known history of this condition should always be checked for the possibility that obstruction has occurred.