Feline idiopathic cystitis-a role for technicians (Proceedings)

Feline lower urinary tract diseases are characterized by hematuria, pollakiuria, and dysuria, and are common problems encountered in feline practice. It is estimated that they affect over one half million cats in the United States annually. Although there are numerous recognized causes of these signs, the exact cause is never identified in the majority of cases. These cases are classified as feline idiopathic cystitis (FIC) and may represent up to 64-68% of non-obstructive lower urinary tract diseases. The biologic behavior of FIC is variable and may be complicated by urinary obstruction due to urethral plugs. Clinical signs in non-obstructed cats often resolve in 2-3 days without therapy, although in about 40% of cats, signs may be frequently recurrent or may persist for longer than 3 weeks. Cats with persistent signs or frequent recurrence of signs are classified as having chronic FIC.

There are numerous theories regarding the etiopathogenesis of FIC. These theories include roles for external factors (i.e. crystalluria, uropathogens such as viruses, urine toxins...), intrinsic bladder factors (i.e. autoimmunity, increased uroepithelial permeability, alteration of the mucosal glycosaminoglycan layer, mast cell infiltration, neurogenic inflammation...), or more internal/systemic problems (i.e. developmental abnormalities, abnormal neurologic or hormonal stress responses...). Unfortunately, identifying basic pathologic processes has been hindered by lack of comprehensive histopathologic descriptions of tissue samples (including urinary bladder and other organ systems) and the challenge of clearly establishing a progression or link between cystitis and con-morbid abnormalities in other systems.

Clinical features of FIC are similar to those observed in an idiopathic lower urinary tract disease of humans referred to as interstitial cystitis. Interstitial cystitis in humans is a chronic, persistent, and debilitating disorder characterized by pollakiuria, dysuria, lower abdominal pain, normal urinalysis results and distinctive cystoscopic lesions called glomerulations. Similarities between the clinical features of idiopathic cystitis in cats and interstitial cystitis in humans have prompted speculation that these two conditions are analogous to one another. These similarities also seem to extend to underlying pathophysiologic disturbances and histopathologic lesions. For this reason, several studies have been performed in cats to try to identify beneficial effects for treatments that have shown promise in human medicine.

One of the primary difficulties in any clinical trial for this condition is identifying when a medication has a truly beneficial effect since the majority of cats will recover from their symptoms within 5-7 days without (or despite) therapy. Thus, it is exceptionally important to determine whether there was adequate placebo control and appropriate masking of investigators and clients when evaluating these studies.

Diagnosis

First of all, in order to diagnose this condition, all other reasonable potential causes of lower urinary tract disease must be ruled out. This usually requires numerous diagnostic tests including a complete medical history and physical examination, minimum data base (Chemistry, CBC, UA), urine culture, imaging (radiographs, ultrasound, contrast studies, cystoscopy), and potentially others (viral testing, histopathology, etc...).

Most of the time in practice the diagnosis is presumptive based upon the cat's clinical symptoms and some of the tests listed here. This is reasonable. However, if the cat is not improving after a week, further evaluation might be indicated to look for an identifiable cause of signs.

Recent evidence has also been presented which suggests that a thorough evaluation of these patients to identify abnormalities in other systems (e.g. chronic gastrointestinal, behavioral, endocrine, or cardiovascular disorders) is warranted.

Treatment options

At this time, because the underlying cause of FIC remains a mystery, current options for treatment are primarily based upon symptomatic relief, practice experience, and theoretical benefits. As we learn more about the disease, there may be more information available to allow identification of better options. Currently we do not expect that any treatment option will "cure" a cat of this condition. Many cats may not have more than one episode, and no treatment is recommended for these individuals. For those cats that have chronic symptoms or frequently recurrent episodes, some of the potential treatment options are listed below. The goal of therapy is to reduce the severity of the symptoms and/or increase the time between episodes.

Interestingly, there is even some evidence that simply taking extra time to explain this disease and convey a sense of understanding and empathy for the client's frustrations may help improve the perceived clinical outcome. The majority of this talk will focus on the role that veterinary professional staff can play in helping cat owners understand their pet's condition and the steps that they can take at home (beyond just giving a medication) that have the potential to have a substantial positive impact.

Diet and water intake

The primary consideration here is to increase the overall water intake of the cat and by extension decrease the concentration of the urine. The primary means of accomplishing this in most cases is by using the canned food formulation of the cat's normal diet. Any change of diet formulation should not be made suddenly, but rather gradually so that there is no added stress associated with the transition.

In addition to the increase water content of canned food, owners should be encouraged to try to increase their cat's water intake in other ways. Consider follow up examinations to monitor the urine specific gravity to help determine if the clients are successful in improving water intake.

There does not appear to be any significant benefit to acidifying the urine or attempting to reduce struvite crystalluria in cats with FIC.

Multimodal environmental enrichment

There is evidence that stress may play a role in the pathogenesis of FIC. Some cats seem to demonstrate improvement when the owners focus on maintaining a minimally stressful and enriched environment. Primary areas of focus include attention to litter box management, access to and location of food and water resources, social interactions (other pets and owners), toys and other enrichments, and awareness of anything else that seems to impact the cat's overall stress level.

One good source for additional information about environmental enrichment for cats is the website for the indoor pet initiative at http://indoorpet.osu.edu/. This site has information for veterinarians and pet owners.

Access and presentation of food and water

Some cats may have preferences about the environment in which they eat or drink. In particular, cats with a high sensitivity to environmental stressors may prefer to eat individually or in quiet, out of the way, locations. Some cats may respond to attempts to simulate some natural feeding behaviors such as hunting/foraging, stalking, and pouncing by hiding small amounts of food or providing food in a container that requires some activity and interaction in order for the cat to extract it.

Some cats have strong diet preferences either for the form of food (dry or canned) or the specific formulation. In general, initially it may make some sense to provide the cat with alternatives simultaneously, rather than sequentially, to gauge preferences. The same also applies to water source and containers

Litter boxes

There are a number of factors to consider when evaluating the litter boxes at home. In general, it is recommended that households have an n+1 rule (i.e. if possible, there should be one litterbox for each cat in the home plus one extra). In addition to the number of boxes, however, factors such as location, size, cleanliness, open or closed top, and the actual type of litter used can all be very important to some individual cats. If possible, litterboxes should be located in quiet, convenient locations that provide an easy escape route for the cat. Boxes should be regularly cleaned and replaced. Litter preference can be determined by providing simultaneous options.

Space

Cat's living spaces should be evaluated to ensure that there is adequate opportunity to climb, scratch, play, hide, and rest. Some cats prefer horizontal or vertical scratching surfaces. Some cats prefer to have an elevated vantage point from which to monitor and assess their environment. Some like to have boxes or other safe and concealed hiding areas available. Sudden auditory changes can also create stress for some cats, and having a radio play can help desensitize some cats to this.

Animal interactions, conflict avoidance

In cases where there are multiple cats in the same household, it is important to try to recognize if there is any conflict or competition between the cats that could be creating, or contributing to, a stressful environment. In many cases, signs of such conflict can be relatively subtle. If signs of conflict are evident, steps should be taken to identify the root cause (e.g. competition for limited resources or space, dominance behavior, lack of escapes, etc...).

Play

Some cats enjoy playing with toys, but there like many other things about cats, they seem to have strong individual preferences for certain types, colors, shapes, movements or other characteristics of these toys. Many cats also seem to prefer novelty or variation and can get "bored" with toys unless they are rotated or replaced regularly.

Human interactions

Similar to play behaviors, cats seem to have strong individual preferences for certain types and amounts of human interaction. Some cats enjoy being groomed or petted, while others prefer active play behavior. People are often very busy and may have a hard time dedicating specific time to interact with their cat in a manner that it prefers. In addition, if the cat has been urinating outside the box, there can actually be some negative feeling towards the cat that influence interactions. Just being aware of the amount of interaction and making an effort to spend some time with the cat can make a big difference in some cases.

Medications

I have another proceedings article for a talk to veterinarians being given at this meeting which contains a bit more information about medications that may be used in some cases of FIC. Medications covered in that talk include:

     • Feline pheromone (Feliway®)

     • Tricyclic antidepressants (amitriptyline, clomipramine) and other antidepressants/anxiolytics (buspirone, fluoxetine)

     • GAGs (pentosan polysulfate, Cosequin)

     • Analgesics

     • Anti-inflammatory medications

     • Antibiotics