Kidney failure is the inability of the kidneys to remove waste products from the blood. The waste products build up producing signs and symptoms of uremic poisoning (high levels of urea in the blood). Signs of uremia are various including vomiting, diarrhoea, anaemia, ulcers on gums and tongue and an ammonia-like breath. Death comes when the cat falls into a coma. One reason why cats die of kidney failure is because untreated uremia causes a wide range of dire health issues. Organs and system are damaged. Also these cats might develop a condition called secondary hyperparathyroidism – a failure to control level of phosphorus and calcium.
But this conclusion is heavily complicated by the simple fact that there are multifarious causes of acute and chronic kidney failure which themselves can make the cat very ill or be a cause of death.
For example, the causes of acute kidney failure include trauma to the abdomen, shock when due to a sudden blood loss or rapid dehydration, a blood clot blocking the artery, heart failure when linked to persistently low blood pressure and reduced blood flow to the kidneys and poisoning such as antifreeze poisoning or poisoning by ingesting Easter lilies.
Causes of chronic kidney failure can include infectious diseases especially feline infectious peritonitis (FIP) and feline leukaemia (FeLV). Anti-inflammatory drugs (non-steroidal anti-inflammatory drugs) during periods of hypotension can cause chronic kidney failure. There are many toxins such as antibiotics that are poisonous to the kidneys when given for prolonged periods or in high doses. Heavy metals such as mercury, lead and thallium are also toxic to kidneys. And elderly cats suffer from kidney deficiency. Hyperthyroidism goes hand-in-hand with chronic kidney failure.
It is absolutely clear, therefore, that if you ask why cats die of kidney failure, you have to address both the causes of kidney failure and the effects of kidney failure on the cat’s health.
There is a bit of an epidemic of kidney failure in elderly cats causing death. Some experts say that chronic renal disease (CRD) affects 8 percent or more of cats ten-years-of-age and older.
Comment: antifreeze is probably one of the most commonly used deliberate poisons for wandering domestic cats. I can’t remember any examples of where a person has been arrested and charged by law enforcement for putting down antifreeze to poison domestic cats. My late mother’s indoor/outdoor Burmese cat was killed by antifreeze put down by a near neigbour, it was believed. Although it is very hard to find evidence of this sort of behaviour. It would be easy for manufacturers to make antifreeze indigestable to cats but they won’t do it.
P.S. I am not a vet. That’s important. This article was written on the back of sensible research and a knowledge of feline anatomy and physiology. There is no substitute for good vet advice.
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