Dilute urine means the kidneys are not functioning properly which probably means feline kidney disease. This is not uncommon in elderly domestic cats.
The kidneys are ‘trash collectors’. The waste from digested food that the kidney’s collect from the blood passes to the bladder and thence to the exterior of the body.
The waste creates the ‘density’ in the urine. If there is little or no waste the urine is more dilute and the kidneys cannot be functioning properly and therefore they are likely to be failing. Also the kidneys are unable to conserve water efficiently. The resultant large urine output means going to the litter box more frequently and increased fluid intake. This contributes to the dilution of the urine.
As a cat owner I have personal experience of this concerning my late lady cat who passed over the rainbow bridge about eight years ago. Her veterinarian said that what she drank was going straight through her. She meant that the kidneys were not filtering out waste in my cat’s blood.
The waste therefore builds up in the blood and damages the body. The signs of kidney disease are well-known and include the retention of ammonia, nitrogen, acids, and other waste products in the tissues and bloodstream. This is called ‘uremic poisoning’. This causes apathy, loss of appetite and ulcers on the gums and tongue. The breath may smell of ammonia. There is vomiting, diarrhoea and anaemia and eventually coma.
I have included three associated posts. There is a question mark over why chronic kidney failure is so prevalent in elderly domestic cats. Is the cause the explosion in use of dry cat food? If so why is nothing being done about it? If you feed dry pellets always do your best to get your cat to drink more water. Explore ways to achieve this.