FELINE IDIOPATHIC CYSTITIS (FIC)
"Idiopathic" means unknown cause; "cystitis" is inflammation of the urinary bladder. Feline idiopathic cystitis (FIC) is a very common problem.
FIC has been called by other names, but this is currently (2014) the preferred term. Feline interstitial cystitis is too specific; feline urologic syndrome (FUS) is outdated; feline lower urinary tract disease (FLUTD) is a broad term that includes FIC and other problems as well.
The cause of FIC is unknown. It has been subject to much research and speculation, but a definitive answer to the question remains elusive. Some things that are commonly thought to be causes are, in fact, not causes:
- Dry food and ash, mineral, or magnesium content of food do not cause FIC
- Crystals or stones in the urine do not cause FIC
- Infection rarely, if ever, causes FIC
One of the most important results in FIC research is the finding that cats with FIC have an abnormally exaggerated response to stress. A normal response to stress involves a complex interplay between the nervous system and the endorcrine (hormone) system; together they are called the neuroendocrine system. Cats with FIC appear to have imbalances in their neuroendocrine system that results in an abnormal stress response.
The abnormal stress response causes the urinary bladder to become inflamed (The mechanism for this has been well-established but is beyond the scope of this article). The lining of the bladder becomes leaky and urine penetrates into the deeper layers of the bladder wall. In that location urine is tremendously irritating and it provokes extremely intense inflammation and pain. Complications of this deep inflammation are many and varied, including bleeding into the bladder, production of mucus, crystals and stones in the urine (which, in turn, can cause a urinary obstruction), and fibrosis (scar formation) in the bladder wall.
Cats are creatures of habit and any disruption of their normal routine causes a significant stress. (Remember that only some cats have an exaggerated stress response; most cats can adequately manage the stresses they encounter without becoming ill.) There are very many things that could possibly stress a cat, and many of these things are beyond our ability to perceive them. In our experience the three most common significant stresses are:
- The presence of multiple cats in the patient's environment
- A change in the people population of the cat's home, for example, a new baby, a family member off to college, a new work schedule for a primary caretaker, houseguests
- Winter weather
Once stress and/or other factors cause physical abnormalities of the urinary bladder, those physical abnormalities, including inflammation and scar tissue, will continue to get worse regardless of whether or not the stress or other factors are removed. Unfortunately, medical therapy might help but cannot completely stop the progress of these physical problems.
SIGNS OF FIC
A consideration of the signs of FIC necessarily includes a description of the signs of urinary obstruction, which is an occasional complication of FIC.
The signs that a cat has FIC include blood in the urine, straining to urinate, urinating small amounts frequently, and urinating in places other than the litter box. These signs vary greatly in severity and persistence from cat to cat.
Urinary obstruction is not FIC, it is a possible complication of FIC. Not all cats with FIC become obstructed. If a cat becomes obstructed then the signs that could be seen include straining to urinate and producing nothing, lethargy, loss of appetite, and vomiting. A urinary obstruction quickly becomes a life-threatening problem, so it is a true emergency.
Some cats that become obstructed will have the signs of FIC for some period of time first, and then the signs of obstruction. Other cats that become obstructed have no "warning" signs; they go from looking and acting completely normal to being very ill very quickly.
FIC is a diagnosis reached by ruling out specific causes for the cat's signs. We diagnose FIC by using the patient's history, physical exam, urine test, and often blood tests, x-rays, and ultrasound exam to try to identify a particular cause for the patient's signs of cystitis. Occasionally urine culture, cystoscopy (endoscopic exam of the bladder), and bladder biopsy are also done. If a reasonable effort is made and no cause is found then the cat is diagnosed with FIC.
Because FIC is a chronic problem with signs that wax and wane repeating various diagnostic tests and carefully evaluation of response to treatments are usually necessary.
TREATMENT OF FIC
FIC is usually not a curable problem. We have found that management can sometimes be so effective that the signs completely resolve. Since a very significant part of the problem is how the individual patient's neuroendocrine system is "wired" to result in the abnormal stress response we remain suspicious that any cat with FIC might relapse at some time, no matter how well their signs appear to be managed.
With veterinary research and clinical experience two treatment options have emerged as the most reliably helpful and successful for long-term management of FIC:
1. Increasing water consumption. The easiest and most effective way to do this is to feed an all-canned diet.
Since cats evolved as desert animals they naturally do not drink much water, so we have to be creative in our attempts to get them to drink more. More comments on encouraging water consumption by cats can be found in the YVCipedia article ENCOURAGING WATER CONSUMPTION BY CATS.
2. Identifying and reducing or eliminating the stress(es) that started the problem. Of course, it is not always possible to identify a particular source of stress, and sometimes when one can be found not much can be done about it.
Whether or not a particular source of stress can be identified we believe it is worthwhile to take a broad approach to modifying and improving the cat's enviroment. Expert advice is provided by the veterinary specialists at Ohio State University's veterinary college; their website is http://indoorpet.osu.edu/.
Other medical treatments and many and varied, ranging from anti-inflammatory medications, antianxiety medications, pain relievers, and nutritional supplements. It is not possible to recommend a standard approach for every cat with FIC; the treatment program must be created (and subsequently modified) for each individual cat by the veterinarian.
The majority of cats with FIC have signs that recur. How often they relapse and how severe a relapse will be is not possible to predict. We can often minimize these signs with medical management, but only rarely can we prevent them from ever relapsing.