DIAGNOSIS
EDTA tube collected whole Blood or cheek epithelial cell samples can be collected to run DNA tests that look for the affected gene, however these will not give us a good indication of how much the disease has progressed. Clinical signs and laboratory testing results don't usually appear abnormal until 70% of renal tissue, and thus function, has been compromised by the cysts. By the time 70% of the kidney is affected, the cat is usually around 7 years old or so however diagnosis can take place earlier or later. Diagnosis is ultimately done via ultrasound. Anechoic fluid filled spaces on the kidney will be seen as well as enlargement and/or distortion of the kidney. The down side to ultrasound is that kittens up to 6-10 months of age have difficulty being diagnosed as the cysts are still very small. Finding the cysts in some older cats can prove to be a challenge and takes a good ultrasonographer as well as ultrasound machine to catch felines with smaller cysts.
This short clip will show you how a kidney with a lot of cysts looks like during an ultrasound.