Prevalence of autosomal dominant polycystic kidney disease in Persian cats and related-breeds in Sydney and Brisbane

Objective - A form of autosomal dominant polycystic kidney disease has been identified in Persian cats and related breeds. Two features make elimination of this disease from future generations an achievable goal: the autosomal dominant mode of inheritance and the availability of a noninvasive technique, renal ultrasonography, to identify affected cats. The aims of this study were; to determine the prevalence of the disease in Persian cats and related breeds in Sydney and Brisbane, to determine any effect of domicile and breed on disease prevalence, to alert veterinary practitioners to the prevalence of autosomal dominant polycystic kidney disease and to propose methods of eliminating the disease from future generations of cattery-bred cats. Design - To be included in this scheme, cats had to be of Persian or related breed and be older that 10 months-of-age. Younger cats were excluded because of the increased likelihood of a false negative result. Renal ultrasonography was performed using either a Medison 600 with a 7.5 Mhz mechanical sector scanner (n=228, Brisbane) or using and ATL UltraMark-9 with a 5 to 10 MHz linear array transducer (n=92, Sydney). The effects of domicile (Sydney versus Brisbane) and breed on the prevalence of autosomal dominant polycystic kidney disease were tested using two-tailed Fisher's Exact tests. Results - A total of 320 cats were tested comprising 230 Persians, 48 Himalayans, 17 Exotics, 14 Burmillas, 6 Ragdolls and 5 Chinchillas. The prevalence of autosomal dominant polycystic kidney disease in Sydney (45%) and Brisbane (42%) was comparable and no sex predilection was identified. The disease was not detected in Ragdolls, although only a small number was tested. Two of 14 Burmilla cats were positive (14%), demonstrating that long hair coat and brachycephalic features do not segregate with the polycystic kidney disease trait. Conclusion - These results show that the prevalence of autosomal dominant polycystic kidney disease amongst pure-bred, long-haired cats in Australia is currently very high. Ultrasound detection schemes are easy to establish and breeder participation can be encouraged through subsidisation.