[Epidemiological data of urinary stones in cats between 1981 and 2008].
Evaluation of urinary stones analysed between 1981 and 2008 in cats and comparison with data submitted, such as breed, age, sex and body weight. Over the given years 5173 feline uroliths from cats in Germany and some neighbouring countries were analysed. From the forms submitted the following data was obtained for most cats: breed, age, sex, body weight, obesity status and location of the urinary stone(s). All uroliths were analysed by infrared spectroscopy. Uroliths containing at least 70% of a single mineral were classified as being of that type. The cats with urolithiasis belonged to 25 different breeds. The most common breed was the European shorthair (64.3%) followed by Persian (15.2%), British shorthair (3.9%), Chartreux (1.7%), Maine Coon (1.5%) and Siamese (1.1%). Most animals were neutered or castrated (81.8%). Tom cats were significantly more frequently affected than female cats. The mean age (7 years) was virtually identical between both sexes, but varied between different stone types. Cats with struvite stones were significantly younger than cats with calcium oxalate stones (6.6 versus 7.6 years). Most urinary stones were retrieved from the bladder and/or urethra (93%). Over the entire time period (1981-2008) struvite (51.2%) and calcium oxalate (38.7%) stones were the two most common urolith types. Percent calcium oxalate stones increased significantly over time and were seen more often in 2008 than struvite stones (48.6% versus 43.4%). Amongst other urinary stones, ammonium urate (1.7%), carbonate apatite (1.7%), cystine (0.5%) and xanthine (0.3%) uroliths were analysed. While struvite and calcium oxalate stones are presently found at approximately equal frequency in cats, various different urinary stones types can also occur in this species. Epidemiological knowledge of urinary stones is crucial as a basis for adequate therapy and prevention.