Where humans have heart attacks and get pneumonia, cats get kidney failure. 50 percent of old cats die of kidney failure, and the other half die of cancer or heart problems (and a few other rare things).
The good news is that over the last few years there has been considerable research and progress in the area of feline renal failure (cat kidney problems). Lo and behold it turns out that cats’ kidneys are NOT like those of dogs, rats or humans which explains why previous attempts at treating cat kidney failure was pretty unsuccessful. So what happens these days? Cats have kept some metabolic secrets from us for some time, and these are now being unravelled. The main one is that in many cats, as the kidneys become damaged, their blood pressure increases – just like ours. The trick has always been how to measure blood pressure because cat arteries are so small. At the Cat Clinic we use a sophisticated Doppler Flow Ultrasonic Detector that picks up arterial wall movement and turns it into noise. This means we can read your cat’s blood pressure measurement with a cuff just like in humans (well, babies anyway!). Treating the high blood pressure keeps the kidneys functioning for longer. In addition we test your cat’s urine to see whether the kidneys are filtering the toxic wastes properly by checking the urine specific gravity with a refractometer and the protein, blood and other components using the same dipsticks that are used on humans. Interestingly, cat urine has a couple of special aspects. One is that normal cat urine is much more concentrated than human urine, as befits an animal that evolved in the desert. And the other is that there are bacteriostatic components in normal cat urine that prevent bacteria growing once the urine is formed. This makes it difficult to culture for bacteria unless the urine is very diluted as it is in the later stages of kidney failure. However, we can check the sediment of the urine to see if there are any bacteria visibly lurking there and treat with antibiotics as necessary. A finding of glucose in the urine is enormously significant as cats can get diabetes, the same as humans. And finally we can check the blood test values of toxic waste products in the cat’s system by checking your cat’s blood levels of urea, creatinine and phosphate. These values give us a good idea about how sick a cat feels from its lack of kidney function.