However, this post is not written exclusively on the basis of cold research as I have had first hand experience of caring for a cat with blood in her urine.
Some time ago, my cat suffered an infection in her bladder causing it to become inflamed. The infection/condition is called Cystitis. Cystitis is simplest of the feline lower urinary tract diseases (FLUTD).
It is not that uncommon in women as well (a lot of the diseases that can be contracted by cats are also found in humans) and certainly quite common in cats.
You can tell when your cat has it because she/he will urinate small spots of dark urine or bloody urine in and outside the cat litter. When my cat had Cystitis she would pass small drops of urine in corners of the room and in the bath and shower (that was nice of her). This "inappropriate elimination" as it is called wasn't due to poor litter training but an extreme urge to go to the toilet, a symptom of Cystitis.
In my cat's case it was due to one of two things. At the time she was on a mainly dry food diet as recommended by the veterinarian. She is a nervous and passive girl so gets overweight easily. She was eating Hills LD (light dry food). This food I believe exacerbated her condition as it can cause the urine to flow less freely (less of it unless your cat compensates with increased water drinking). Less free flowing urine is more static which presents a good and fertile material inside the cat for a bacterial infection which in turn causes inflammation and then bleeding in a more extreme case.
To prevent this I feed her fish with added water sometimes and now I feed her much more wet food. Dry food, due to the nature of its manufacture has too high a level of carbohydrates in it which is unnatural for a cat and it encourages over eating and can be a factor in becoming overweight and causing diabetes. She still eats dry food but much less. She is healthier and more active I believe. Overweight cats and older cats seem to be more prone to getting Cystitis. It could be argued that a carefully controlled raw food diet with supplements is best for your cat (some breeders feed their cats raw food). I have posted an article about urinary tract cat food on this website.
This is a nice picture of a cat at the vets. Photo by jilbean3 under a creative commons license.
Another reason for the Cystitis was stress brought about by her nervous demeanor. She is nervous because of an early difficult life as a stray cat. The vet gave some de-stressing medication but the best cure was plenty of wet food and love from me. I would certainly look carefully at the stress issue. It can be hard to tell if your cat is stressed. Rather than trying to figure out what might cause stress the best thing to do it to create and environment that you know will not be stressful. This will entail creating an environment that is as natural as possible for the cat.
Things which come to mind from experience are, your company (provided it is loving, gentle and interactive), quiet, routines, space to explore, stimulation through watching and playing, the possibility to go out (provided it is secure - a good compromise is a cat enclosure).
One of the best "cat-at-a-vet-pictures". photo by Chuckumentary. The other best picture (and the best, I think, can be seen at the top of the Cat Health Problems page of this website)
These are more commonly encountered in young middle-aged cats and old cats and can cause blood in cat urine. The symptoms could be a history of blood in the urine. X rays are used to diagnose the presence of tumours. Surgery is possible but if the tumour is too advanced the only answer if euthanasia sadly.
Another cause of blood in cat urine is trauma or injury. If the bladder ruptures (broken and torn releasing urine into the abdominal cavity) it is to be expected that there will be blood in cat urine.
Leakage of urine into the body will naturally cause the cat to become sick. Symptoms are depression, vomiting, lack of appetite and poor production of urine, straining to urinate, blood in urine. (src: http://www.petplace.com/). This may, it seems to me, give the appearance of urinary tract disease so a vet's diagnosis is obviously vital.
Rupture may also be a result of severe inflammation referred to above.
Trauma can occur in many ways, for example, being hit by a car or falling from a height. Cats will find a quiet spot when feeling unwell. This would be another sign of illness.
Urinary Tract Obstruction
This may cause bladder rupture due to the cat straining to urinate beyond the tensile capacity of the bladder wall. The underlying cause will be the obstruction. One cause of obstruction is the formation of crystals (stones) in the tract. Answer: see a vet.
Blood in cat urine to Cat Health Problems
Blood in cat urine - Sources:
- Veterinarian Notes for Cat Owners by Trevor Turner and Jean Turner
- The Veterinarian's Guide to Your Cat's Symptoms
- Petplace (Dr. Jon)