Feline Polycystic Kidney Disease (PKD)
Feline polycystic kidney disease is an inherited disorder characterised by development of small, closed, liquid-filled sacs in the tissue of the feline kidney. These sacs often multiply in number and grow in size over time, eventually outnumbering normal kidney tissue and often leading to potentially fatal kidney failure.
Kidney function deteriorates with age and kidney disease occurs between 3 and 10 years of age, with an average of seven years. Kidney cysts are evident through ultrasound scans by 8-10 months of age, although severity and progression of the disease varies widely between individuals. Mildly affected cats may throw more severely affected offspring and vice-versa.
PKD in cats is characterized by renal as well as hepatic and pancreatic cysts and has an autosomal dominant mode of inheritance. Approximately 38% of Persian cats in the United States and worldwide are positive for PKD. Purebred cats represent ~20% of the cat population in the United States, and Persian-type breeds constitute 80% of the cat fancy; hence, PKD is the most prominent inherited feline disease.
The causative mutation of the PKD-1 gene has been identified and a DNA test is available for Persian and related breeds.
Lyons, L.A., Biller, D.S., Erdman, C.A., Lipinski, M.J., Young, A.E., Roe, B.A., Qin, B., and Grahn, R.A. (2004). Feline polycystic kidney disease mutation identified in PKD1. J. Am. Soc. Nephrol. 15, 2548–2555.
Shelton, L. and Helmrich, H.G. (2006). Heritable diseases and abnormalities in cats.