Are your feline patients trying to tell you something?
When they visit the clinic with their owners, who bring them in with complaints about their pets' irritable moods and poor litter box habits, the cats may be presenting with a one of several medical conditions associated with feline lower urinary tract disease, or FLUTD, says Jacqueline Neilson, DVM, Dipl. ACVB, of Animal Behavior Clinic LLC in Portland, Ore.
"FLUTD is a catch-all term to describe any disorder affecting the urinary bladder or urethra," she explains. "It's quite common. In fact, for years some kind of lower urinary tract disease sign has been the most common medical reason policy holders of pet insurance take their cat to the vet."
Dru Forrester, DVM, MS, Dipl. ACVIM, associate director, scientific affairs and technical information services for Hill?s Pet Nutrition in Topeka, Kan., adds that for veterinarians, the signs associated with FLUTD can be linked to a number of underlying issues—and that makes pinpointing the cause and treating it a challenge.
"No matter the cause, they often have the same signs, and that's the frustrating part about [FLUTD]," Dr. Forrester says. "Any disease that affects the lower urinary tract typically causes the same four or five clinical signs."
The Common Signs
Owners with cats suffering from FLUTD will often bring their pets in when they begin acting inappropriately.
Of the five signs exhibited by a cat with FLUTD, outside-the-box house soiling, known as periuria, is the most common complaint, reports Dr. Neilson. She says 92 percent of cats with feline idiopathic cystitis, one of the causes of FLUTD, show some level of periuria.
"What owners notice and what often prompts a veterinary visit is the inappropriate urination somewhere outside the litter box," Neilson says.
Stranguria, the term used to describe cats straining to urinate, is another behavior owners may observe, says Forrester. "That's when a cat is trying to pass urine but can't get any out, or only a small amount out," she says. "So you'll see a cat sit in the litter box or go back and forth, trying and trying. That's a really big warning sign that a male cat may be obstructed."
Pollakiuria, or increased frequency of urination, may also be observed, Forrester says. Owners may describe that their cats go back and forth to the litter box over and over, or it have continual accidents because they can't make it to the litter box in time. "It's characterized as urgency to go," she says.
Though many times too microscopic for the naked eye to see, blood may be present in the urine of a cat with FLUTD, Forrester suggests, adding that the technical term for this condition is hematuria.
"[The blood] can be visible, or it may not be," she says. "If the owner sees a pink or red discoloration of the urine, then it's pretty clear cut. But many times, the veterinarian will have to take a urine sample and look at it under a microscope."
Cats that feel pain when urinating may cry out, too, Neilson says. "Another clinical sign is vocalization," she adds.
Causes of FLUTD
Cats that show these signs may be suffering from one of the three main causes of FLUTD, Neilson says, the most common of which is feline idiopathic cystitis. Unfortunately, she says, veterinarians don't know FIC's pathogenesis.
"FIC makes up anywhere from 55 to 65 percent of lower urinary tract diseases," she says. "We don't know what causes it—but we do know what the risk factors are."
Forrester, noting the research of The Ohio State University's Tony Buffington, DVM, Dipl. ACVN, says that an FIC diagnosis is one of exclusion. "Cats are in an environment that's perhaps not typical for their natural behaviors," she says. "The stress associated with that might affect the neurologic pathways and result in secondary inflammation in the bladder and this condition that we call idiopathic cystitis. There's no diagnostic test for that, so what we have to do is rule out everything else."Neilson says stress, for example, may aggravate the disease in cats genetically predisposed to it. She says being an indoor cat may be a risk factor, as well as being obese. "There are lots of risk factors, but we're not to the point of knowing causation yet," she says.
Uroliths, or bladder stones, are another FLUTD cause. These stones are made up of different minerals, most commonly struvite and calcium oxalate, and may form when there is an excess of minerals in the cat's urine.
"There are other factors involved, too," Forrester continues. "Urine pH is critical for struvite stones because an alkaline pH above 6.4 to 6.5 increases the likelihood of that mineral precipitating out into the bladder."
Urethral plugs may also cause FLUTD, Forrester says. A plug is composed of a gelatinous material that gets stuck in a cat's urethra, she says. "And in cats, they are almost always composed of struvite, but they are distinctly different from struvite stones," she says. "The plug can get stuck in the urethra in a male, and that can lead to urethral obstruction, which is life-threatening."
Treatment Challenges, Options
When developing a treatment plan, veterinarians first must determine the cause of the disease and then treat accordingly, say Forrester and Neilson.
"If you're looking at a typical young- to middle-aged cat, every veterinarian and technician should be walking around with those top three causes in their heads, and then do their diagnostic evaluation to confirm what's going on," Forrester says.
Veterinarians who diagnose cats with FIC often advise environmental enrichment to reduce the animal's stress level, Neilson says. "At this point, we don't feel we can cure FIC, so what we're really trying to do is reduce the incidence of recurrence of those flare-ups," she says.
Environmental enrichment can be achieved in many ways, including adding extra litter boxes and scratching surfaces, providing perches and safe resting spots, interacting and playing with the cat, introducing extra feeding stations, and mitigating household inter-cat squabbles if necessary, Neilson says. "To create an 'environment of plenty,' you really look at the cat's scratching, resting, eating and drinking resources, and explode those resources in whatever environment they have," she explains.
Cats with FIC, as well as those with stones or plugs, may also benefit from eating a wet pet food, Forrester says. The challenge, however, is that because some cats prefer crunchy food to moist, the stress of switching from one to the other could make the disease worse, she says.
Another challenge with a wet pet food: Some may contain high levels of the substances that cause uroliths and plugs, Forrester says. Struvite, the main component of stones and plugs, is made up of magnesium, ammonium and phosphate. If a cat with stones or plugs eats a pet food with higher levels of these ingredients, that diet could lead to more problems.
"Treatment for struvite is to feed a pet food that maintains a urine pH below 6.4 or below and to avoid excessive minerals that would be there to form the struvite stone," she says, noting that the best way to do this is through a therapeutic pet food formulated to manage the most common feline lower urinary tract diseases. Some of these foods, she says, can even dissolve uroliths.
"A recent study has shown that struvite stones can be medically dissolved in some cats in as little as two weeks by feeding Hill's Prescription Diet c/d Multicare Feline Bladder Health," she reports. "The average time it takes to dissolve is about 28 days. We're trying to get the profession accustomed to thinking food over surgery because surgery isn't 100 percent effective, either."
Urethral plugs, Forrester says, must be removed with a catheter, then the cat's bladder must be flushed, and the animal must go on a specially formulated diet. Animals with calcium oxalate stones must undergo surgery to have them removed.
The majority of FLUTD causes, however, can be managed with stress reduction and dietary changes, Forrester says. "Unless you know for sure what the cat has, it's safest to recommend a therapeutic management pet food," she says.
This Education Series article was underwritten by Hill's Pet Nutrition of Topeka, Kan.