Vet: Is your cat down in the mouth?
August 18, 2005
Michelle Gerhard Jasny, VMD
I was a little late for a lecture at the Northeast Veterinary Conference, which I attended earlier this month in Rhode Island. Dr. Alice Wolf, a feline internal medicine specialist from Texas A & M University, was speaking. I arrived to find people jammed into the large room, sitting on the floor, overflowing into the halls. Now in other rooms were lectures on GI surgery, Emergency and Critical Care of Rabbits, Vascular Hepatopathy, Multimodal and Preemptive Analgesia, but it was this room that was drawing the crowds. The subject? Gingivitis in Cats. Doesn’t sound exactly scintillating, does it? OK. To be perfectly honest, the lecture was entitled Gingivitis, Stomatitis, and Other Oral Cavity Lesions. Still, you might wonder why this was the hot topic.
Gingivitis is defined as inflammation of the soft tissues surrounding the teeth. Let’s take a hypothetical cat, Abby. Her gums are bright red right along the tooth margins. They may be a little swollen and bleed when touched. In most cases, Abby’s owners don’t even notice until a veterinarian points it out during a routine exam. She may also have stomatitis — sores in other areas of the mouth. Cats with gingivitis/stomatitis may exhibit halitosis, ptyalism, and anorexia. That means Abby has bad breath, drools, and won’t eat. She may eat soft food but refuse dry, or pick up food but then let it fall out of her mouth. She may gag, sneeze, have nasal discharge, or pain on opening the mouth. But in many cats, even those with serious cases, owners may not notice any problems.
Simple gingivitis may result from plaque accumulation and sometimes be rectified by a professional dental cleaning followed by regular brushing (using veterinary toothpaste) and feeding special diets designed to reduce plaque and tartar. Antibiotics for secondary bacterial infections are often helpful. However, all too often, routine dental care does not eliminate gingivitis. In these situations, were we to take a biopsy of the affected tissue, we would probably get a diagnosis of lymphoplasmacytic gingivitis/stomatitis (LPS.) Sounds official. Sounds serious. "What causes that?" you ask. Well, we dunno. That’s right. LPS is a histopathologic description, not an etiologic diagnosis. In other words, it just describes what the tissue looks like under a microscope, not why it got that way.
Plaque or cavity
There are probably several different causes of LPS. The simplest is "plaque intolerance." These cats are highly sensitive to any plaque accumulation and need extremely thorough and regular dental care. Abby may also have Feline Oral Resorbative Lesions (FORLs), kind of the kitty version of a cavity. FORLs may be hidden below the gum where your veterinarian can find them by gently using a probe to check for holes and tender spots. Cats with no visible FORLs may still have deeper root lesions that can only be evaluated by dental X-rays. Gingivitis will often persist until the affected tooth is removed. Removing all the teeth is sometimes advised for severe cases of gingivitis that do not respond to other modes of therapy, but this is a drastic undertaking that should only be done in cases that clearly fit specific criteria and as a last resort.
First, we clean Abby’s teeth and deal with any FORLs. She still has LPS. What now? One current theory is that LPS may be caused by Bartonella infection, the organism responsible for cat scratch fever in people. Dr. Wolf does not agree, but that’s another column. It doesn’t hurt to test for Bartonella, although a positive test doesn’t necessarily mean that Bartonella is causing the oral lesions. It doesn’t hurt to treat with the appropriate antibiotic (azithromycin.) This may help with other bacteria infections anyway. But in my experience, let’s just say I agree with Dr. Wolf on this one. What about Feline Leukemia Virus (FeLV) or Feline Immunodeficiency Virus (FIV)? When I was in vet school, we were taught that many cats with LPS had these viruses. Not so, says Dr. Wolf, although she still advises FeLV / FIV testing, as it can affect prognosis and treatment. There is another virus that has been implicated — calcivirus, one of the group that causes feline Upper Respiratory Infection. We don’t have an easy affordable test for it, but if Abby had a URI as a kitten, chronic calcivirus infection may well be at the root of her mouth problems.
A magic bullet?
The bottom line is that we can’t always pin down a definitive cause nor do we have any one treatment that is effective for all cats. That’s why the lecture hall was packed with veterinarians tired of feeling inadequate. Can’t tell you what it is, can’t tell you why she’s got it, can’t tell you how to fix it...and we see it all the time. Most common in middle-aged to older cats, LPS sometimes occurs in younger cats too, especially in certain purebreds such as Abyssinians and Somalis. (In fact, breeders of these cats simply call it "red gum" and some consider it normal.) We were all hoping Dr. Wolf had a new magic bullet.
No such luck, but she did have a list of things to try. Rule out contact plastic allergies by serving food and water in glass, ceramic, or metal bowls. Feed a hypoallergenic diet to rule out food allergy. Feed a high protein, low carbohydrate diet to alter oral microflora. Try a variety of antibiotics for bacterial and Bartonella infection. If they help, repeat antibiotics as needed. Control pain so she can eat. If necessary, resort to corticosteroids, which are still the cornerstone of LPS treatment. Oral if possible, injectable if Abby is too painful to take pills. Don’t mix corticosteroids with certain pain medications that can predispose her to gastric ulcers. One interesting tip that was new to me was a product called Lactoferrin, a protein derived from whey marketed over-the-counter as a food supplement. Dr. Wolf hemmed and hawed apologetically, but cited a study indicating that Lactoferrin applied topically improved some LPS cats. You can get it at health food stores or at www.herbsmd.com. Open up a 350 mg capsule and sprinkle it in Abby’s mouth or rub it along the gums once daily. If she won’t let you do this, mix the powder in soft sticky food, like meat baby food, and let her lap it up. The goal is to coat her oral lesions with the stuff. If it helps, continue indefinitely…and call me. My colleagues and I are all anxiously awaiting a simple, reliable cure for this common but frustrating problem.