LitterBox Behavior Solutions

Blood in the urine is a common finding in cats with litter box problems. What most people don't realize, however, is that this blood is usually from inflammation, not a true bacterial urinary infection, especially in younger cats. Most of the time this inflammation, called idiopathic cystitis, results from a combination of stress, insufficient water intake, diet, and a genetic tendency toward lower urinary tract disease. Sometimes, however, especially in older or debilitated cats, a true bacterial infection is involved that requires appropriate antibiotic therapy. These infections can involve both the bladder and the kidneys and can be very painful. Kidney infections can also damage the kidneys and cause kidney failure.

Many cats with cystitis run back and forth to the litter box frequently or may lick their urethral area excessively. They may strain to urinate because of the discomfort.  Male cats that are showing any of these signs need immediate veterinary care as they may  have a complete urethral obstruction, which is fatal if left untreated.

Some cats have a urinary diverticulum, a pouch that occurs when the urachus (the tube running from the bladder to the umbilical cord in the unborn kitten) does not seal and wither away after  birth. This urachal diverticulum can predispose cats to cystitis. It is thought that antibiotics do not penetrate well into this pouch and bacteria along with other toxic substances are able to persist long term in the pouch. 

So why do we see so many cats with inflammation in their bladder?  A lot of research is being performed to investigate the causes of cystitis in cats.

Domestic cats evolved in the desert, with a diet of small game such as rodents, other small mammals, lizards, and birds. They had a very active lifestyle with a substantial amount of exercise often needed to catch their prey. They lived independently  outside, in small family groups, and in colonies with the freedom to move about over fairly large spaces. These cats and social groups tended to develop certain territories, with some migration of cats back and forth. 

In society today, cats are usually confined inside homes, often in relatively small spaces, and may share the home with other cats in closer quarters than they they would choose. This increases their stress levels, just as overcrowding increases our stress levels.

Many indoor cats are relatively inactive and become obese. Obesity contibutes to inactivity, and so a vicious cycle occurs. These less active cats tend to drink and urinate less frequently, and irritating substances in the urine are able to have longer contact with the bladder lining.  

As a society we tend to feed grain based commercial dry cat foods, often with fish added as well as a palatable protein source. Although these foods may be nutritionally complete, cats are carnivores, and their bodies require meat to work properly.  Some cats appear to be more genetically more sensitive to dietary issues and stress, and are more likely to develop cystitis than other cats.

"But, Doc, I gave my cat an antibiotic and she got better, and now the infection must be back  again because she is going outside the box again!"   Cystitis is a chronic, cyclical and often self limiting disorder. This means that frequently improvement will be seen in  a few days whether any treatment is given or not , and then relapse occurs a few days or weeks thereafter. The key is to get a definitive diagnosis of idiopathic cystitis, and then treat the underlying inflammation both  directly and by addressing and reducing the instigating causes.

 Some cats, particularly male cats, may develop a life threatening urethral obstruction due to mucous inflammatory plugs, excessive urine struvite  crystal formation or small calcium or struvite bladder stones. These cats will die if their urethral obstruction is not relieved by placing a urinary catheter. 

 struvite crystals - Wikipedia

Proper treatment may not completely prevent flare-ups, but it usually reduces the frequency, severity and duration of the episodes. Treating with antibiotics without a urine culture is not recommended, since most cats do much better long term by using appropriate medications and environmental and dietary changes to reduce the inflammation. In addition, using antibiotics when bacterial infections are not present increases the chance for antibiotic resistant bacteria to develop making true infections much harder to treat later. Besides, medicating most cats can be a little challenging- why give these medications unless they are really needed!

Diluting the urine is an integral part of treating cystitis. Feeding a canned food diet that is high in meat protein and low in graines an other carbohydrates is  particularly helpful. Mix water with the canned food to form a slurry or "kitty soup" and to encourage the production of a dilute urine.

Pain medication can be very helpful in keeping the cat more comfortable when inflammation is present. Managing the discomfort reduces the risk that the cat may eliminate outside of the box. DO NOT use over the counter pain medications- these are poisonous to your cat. Prescription pain medications are available and are usually effective and relatively low risk. Most pain medication is considered to be off label for use in the cat and owner consent should be obtained before use.

Male cats who have urinary tract blockages (and very rarely female cats as well) need to be treated initially with a urinary catheter placement, pain medication, fluid therapy, and diet changes. If the urinary blockage reoccurs, or does not resolve well initially, a surgery called a perineal urethrostomy can be performed to make the urethra wider.