Is a Single Cyst in One Kidney Conclusive for PKD?
Absent any other information, the classic answer is “no, PKD is bilateral and requires multiple cysts”. However, evidence suggests that cysts from other causes are relatively rare. So particularly for Persians, Exotics and other cats with direct Persian lineage, if either parent is positive, or if there are positive offspring from a negative mate, or even if the cat in question is young (certainly under 1 year, and perhaps even up to two years), it would be wisest to consider the cat “questionable” or even “probable”, not use the cat for breeding immediately, and rescan the cat closer to two years of age. To quote Dr. Biller, the acknowledged expert on feline PKD and Associate Professor Department of Clinical Sciences College of Veterinary Medicine Kansas State University : “I use to believe that PKD meant bilateral. But I’m not sure that is true. I think that maybe histologically it is true but that maybe we are not seeing cysts bilaterally. I also have seen some cats with unilateral
