The oral lesions associated with feline gingivostomatitis are often mistaken for an oral infection; however, gingivostomatitis is not an infection but rather an inflammation. The inflammatory lesions associated with feline gingivostomatitis are thought to be the result of a highly reactive immune system. The specific antigen that the immune system is reacting to is not easily identified and is often unknown. The fact that most of these lesions will resolve when the teeth are removed suggests the involvement of an antigen that is intimately associated with the teeth (i.e. bacteria). However, because not all inflammation resolves when the teeth are removed, it must be conceded that multiple antigens may be involved. Other antigens that may have a role in triggering the oral inflammation associated with feline gingivostomatitis include viral, food, or environmental antigens. Autoimmunity may also be a component of the disease.
Differential diagnoses for oral inflammation in a cat include feline gingivostomatitis, periodontal disease, inflammation secondary to feline odontoclastic resorptive lesions (FORLs), certain viral diseases (infection with feline herpesvirus or feline calicivirus) that can cause oral inflammation and ulceration, eosinophilic granuloma, oral ulceration secondary to uremia, and neoplasia. A complete patient evaluation is paramount to making a correct diagnosis and embarking down a specific treatment path.
To begin this evaluation, perform a physical examination, a complete blood count and serum chemistry profile, and serologic testing for feline leukemia virus and feline immunodeficiency virus infections. Perform additional testing and imaging as indicated. The results of these tests in cats with feline gingivostomatitis are usually unremarkable except for oral lesions, mandibular lymphadenopathy, and hyperglobulinemia.
Histologic examination results in cats with feline gingivostomatitis show plasmacytic stomatitis or lymphocytic-plasmacytic stomatitis. There may be concurrent neutrophilic inflammation or even a superficial bacterial component, but the predominant population of cells will be plasmacytes and lymphocytes.
In rare cases, simply maintaining excellent oral hygiene will keep this condition under control. A home-care program may include daily tooth brushing and chlorhexidine (topical) application and long-term or long-term intermittent (pulse) antibiotic therapy. Antibiotics whose spectrum of activity includes gram-negative anaerobic bacteria are good empirical choices. Antibiotic therapy often produces favorable results initially; however, the benefits of antibiotic therapy seem to diminish over time. The Catch-22 of feline gingivostomatitis is that the cats that have had sore mouths for a long time are usually the poorest candidates to cooperate with a home-care regimen. When home care alone is not working or not possible, consider medical or surgical treatment.
Unfortunately, the medical treatment options include either drugs with poor chances of success or drugs with serious side effects (e.g. corticosteroids). Many drugs have been used to treat feline gingivostomatitis with varying degrees of success. The most effective drug appears to be methylprednisolone acetate given at a dosage of 20 mg/cat injected subcutaneously every three weeks as needed. Other corticosteroids, such as oral prednisone, have also been used to successfully control feline gingivostomatitis. The goal is to find the lowest every-other-day oral dose that provides clinical control of the disease. Long-term corticosteroid treatment is not ideal because cats can develop serious side effects, including diabetes mellitus and iatrogenic hyperadrenocorticism. Avoiding corticosteroids is especially important when treating cats infected with feline leukemia virus or feline immunodeficiency virus.2
Nonsteroidal drugs that have been used to treat feline gingivostomatitis with limited success include interferon, cyclosporine, bovine lactoferrin, piroxicam, azathioprine, and gold salts. Many of these drugs are not labeled for use in cats and may have marked side effects.
When extracting teeth to treat feline gingivostomatitis, the question arises whether to extract canine and incisor teeth. A suggested approach is to extract canine and incisor teeth if they are diseased or if the surrounding tissues are markedly inflamed. If canine and incisor teeth are sound and inflammation is limited to the caudal portion of the oral cavity, the canine and incisor teeth may be spared.
Perform a radiographic re-examination of the dental arches to rule out retained root fragments or reactive periodontal tissue. If a patient's canine or incisor teeth were initially spared, extract these teeth now.
In some cases of refractory stomatitis, nonsteroidal anti-inflammatory drugs (NSAIDs) will provide relief. One NSAID that has shown effectiveness in cats with refractory stomatitis is piroxicam,4 which can be compounded into a liquid and administered at a dosage of 1 mg/cat orally every 72 hours. Side effects of piroxicam include gastrointestinal ulceration. Meloxicam (Metacam—Boehringer Ingelheim) is another NSAID that is not labeled for oral administration in cats but that may help control pain and inflammation. Avoid combining piroxicam, meloxicam, or any other NSAID with corticosteroids because it increases the probability of gastrointestinal ulceration.
Immunosuppressive and immunomodulatory drugs, such as cyclosporine, interferon, and azathioprine, can be used instead of NSAIDS to reduce oral inflammation, although the response varies and can take weeks to produce favorable results. To avoid serious or potentially fatal side effects, appropriate patient monitoring is paramount, especially when using azathioprine.
Laser ablation of the inflamed oral tissue has also been recommended. Tissue that has been treated with a laser has a reduced blood supply and may be less likely to become inflamed.5
1. Harvey CE, Emily PP. Small animal dentistry. St. Louis, Mo: Mosby, 1993;151.
2. Wiggs RB, Lobprise HB. Domestic feline oral and dental disease. In: Wiggs RB, Lobprise HB, eds. Veterinary dentistry principles and practice. Philadelphia, Pa: Lippincott-Raven, 1997;482-517.
3. Hennet P. Chronic gingivo-stomatitis in cats: long-term follow-up of 30 cases treated by dental extractions. J Vet Dent 1997;14:15-21.
4. Manfra S, Urbana Ill: Personal communication, 2002.
5. Lyon KF. Gingivostomatitis. Vet Clin North Am Small Anim Pract 2005;35:891-911.
The information and photographs for "Dental Corner" were provided by Daniel T. Carmichael, DVM, DAVDC, Veterinary Medical Center, 75 Sunrise Highway, West Islip, NY 11795.