Environmental modification
Environmental modification is an important aspect of treatment.4,5 The litter box must be a clean, acceptable, and accessible place to encourage the cat to eliminate normally. Anything that
hampers litter box use may increase the time the cat retains urine between eliminations. Prolonged exposure of the bladder
wall to urine in cats with increased bladder wall permeability may increase access of "toxins" (e.g. acid, potassium, nitrogenous wastes) to suburothelial structures, which also may activate local inflammatory mechanisms. Litter
box design, numbers, locations, obstacles, and cleaning schedules as well as litter type all influence a cat's litter box
usage and should be discussed with clients.
Decreasing the cat's urine specific gravity below 1.030 is a treatment target and can be attempted by switching from dry to
canned food or adding water to dry or semi-moist diet formulations, as long as the diet change or new diet is not aversive
to the client or the cat. Owners also can encourage these cats to drink more water from their cats' preferred water sources
such as a fresh-dispense bowl or even a running faucet in the sink, or by adding meat or fish-flavored ice cubes to their
water if they like that. Acidifying the urine to minimize struvite crystalluria is usually not indicated.
Conflict between cats or other animals in the household or threats from outdoor cats can be a source of stress, so talk with
owners about providing separate resources that each cat can use without interference from other animals.
Providing opportunities for owner-cat interaction and activity such as playing with toys that mimic prey motion or that intermittently
release food are helpful. Methods to increase indoor space that the cat uses include providing vertical and horizontal scratching
surfaces as well as objects to climb and areas in which to hide, perch, look outside, and rest undisturbed.
Based on our clinical experience, we also encourage owners to use synthetic feline facial pheromone products to augment other
enrichment efforts. Feliway (Ceva Santé Animale) can be sprayed in the affected area of the environment or dispersed into
larger areas by using an electric diffuser.
Additional environmental modification and medical management
If a cat continues to have signs of idiopathic cystitis, review the environmental modifications with the owners to find out
what worked and what did not work and why. Suggest alternative or additional environmental modifications if needed, and consider
including increased supervised exposure to the outdoors for some cats.
We sometimes prescribe amitriptyline (5 to 12.5 mg/cat orally once a day, always using the lowest possible dose) or another
tricyclic antidepressant when environmental modifications as described above have not sufficiently reduced the cat's clinical
signs. We taper the dose gradually and stop it whenever possible after at least three months of use, and we use the drug cautiously
if at all in cats with heart disease. We also perform a complete blood count and serum chemistry profile to monitor the platelet
and white blood cell counts and liver enzyme activities before and at one, three, and six months during therapy.
Additional medical therapy may include increasing the dose of buprenorphine. Unfortunately, glucosamine6 and pentosan polysulfate7 have been found to be ineffective therapy for feline idiopathic cystitis.
FOLLOW-UP
If a cat's clinical signs do not resolve or if the signs recur, you can perform additional diagnostic evaluation (repeat the
complete blood count, serum chemistry profile, and urinalysis, and consider performing or referring the cat for cystoscopic
evaluation) to rule out problems other than idiopathic cystitis.
Controlled clinical trials may provide additional information about the best approach to managing cats with idiopathic cystitis,
but in the interim we have had success with the aforementioned environmental and medical management procedures.
Dennis Chew, DVM, DACVIM C.A. Tony Buffington, DVM, PhD, DACVN College of Veterinary Medicine The Ohio State University 601 Vernon L. Tharp St. Columbus, OH 43210
REFERENCES
1. Buffington CA, Westropp JL, Chew DJ, et al. Risk factors associated with clinical signs of lower urinary tract disease
in indoor-housed cats. J Am Vet Med Assoc 2006;228(5):722-725.
2. Westropp J, Buffington CAT, Chew DJ. Feline lower urinary tract diseases. In: Ettinger SJ, Feldman EC, eds. Textbook of veterinary internal medicine. St. Louis, Mo.: Elsevier-Saunders, 2005;1828-1850.
3. Buffington CAT. Comorbidity of interstitial cystitis with other unexplained clinical conditions. J Urol 2004;172(4 Pt 1);1242-1248.
4. Westropp JL, Buffington CAT. Feline idiopathic cystitis: current understanding of pathophysiology and management. Vet Clin North Am Small Anim Pract 2004;34(4):1043-1055.
5. Buffington CAT, Westropp JL, Chew DJ, et al. Clinical evaluation of multimodal environmental modification (MEMO) in the
management of cats with idiopathic cystitis. J Feline Med Surg 2006;8(4):261-268.
6. Gunn-Moore DA, Shenoy CM. Oral glucosamine and the management of feline idiopathic cystitis. J Feline Med Surg 2004;6(4):219-225.
7. Chew DJ, Bartges JW, Adams LG, et al. Randomized, placebo-controlled clinical trial of pentosan polysulfate sodium for
treatment of feline interstitial (idiopathic) cystitis, in Proceedings. Am Coll Vet Intern Med, 2009.
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