Feline stomatitis/gingivitis: How frustrating is that? (Proceedings)

In a recent survey of the health status of over 31,000 dogs and over 15,000 cats examined at veterinary practices in the United States, the most commonly reported disorders were dental calculus (20.5% prevalence in dogs; 24.2% in cats) and gingivitis (19.5% prevalence in dogs; 13.1% in cats) (Lund, Armstrong et al. 1999).

Gingivostomatitis

Chronic gingivostomatitis is a condition characterized by persistent inflammation of the oral mucosa. The mucosa and gingiva may appear hyperemic, proliferative, and ulcerative with a bright red cobblestone appearance. It can be debilitating, frustrating to treat, and may result in euthanasia. It may be referred to by other names, such as plasma cell stomatitis-pharyngitis, chronic faucitis, lymphocytic plasmacytic gingivitis-stomatitis and others. Prevalence data is scarce, but in one study from the U.K. involving 4,858 cats seen by primary care practices, the prevalence was 0.7% (Healey, Dawson et al. 2007).

The disease varies in severity and may include faucitis, pharyngitis, or palatitis. Clinical signs include drooling, halitosis, bleeding gingiva, decreased grooming, and oral sensitivity. Severely affected cats may develop dysphagia, partial anorexia, and weight loss. In addition, the chronic inflammation may contribute to progressive periodontal disease. The diagnosis is based on clinical signs and histopathology. The most common histopathologic findings include abundant plasma cells, lymphocytes, and occasional neutrophils and macrophages.

The etiology of chronic gingivostomatitis is unknown, but it is likely to be multifactorial. It has been proposed that the disease is an exaggerated immune response to plaque and the tooth structure itself or the periodontal tissues as well as infectious antigens. Other potential factors include genetic predisposition and nutritional factors.

Many organisms, including viruses and anaerobic bacteria, have been found in association with gingivostomatitis. The most commonly suspected infectious etiology is feline calicivirus (FCV), but the feline retroviruses (FeLV and FIV), feline herpesvirus (FHV), and Bartonella species have been implicated as well with variable results in different studies. A causal relationship is difficult to prove because all these infectious agents may be harbored by both healthy and ill cats and the diagnostic methods used in various studies are not standardized.

In a study of 78 British and 18 North American cats with chronic stomatitis and appropriate controls, FCV was more prevalent in cases than controls. In the British cats, the prevalence of FIV was also significantly higher in cats with stomatitis (Knowles, Gaskell et al. 1989). In another study of 25 cats with chronic gingivostomatitis, 88% of cats were shedding both FCV and FHV, compared to 21% of cats without oral inflammatory disease (Lommer and Verstraete 2003). In a large study of 8,982 cats with oral disease including gingivitis and stomatitis, 14.2% of the cats were positive for FeLV and/or FIV (data on file, IDEXX Laboratories, 2006). A recent study of a colony of cats (9 affected cats, 36 unaffected controls) using blood samples and oral swabs found no correlation between gingivostomatitis and Bartonella, FHV, FCV, FeLV, or FIV (Quimby, Elston et al. 2008).

The role of Bartonella species remains controversial. In a study of serum samples from 728 cats in Switzerland, there was an increased frequency of stomatitis in sick cats positive for B. henselae (Glaus, Hofmann-Lehmann et al. 1997). In another study of 34 cats with stomatitis and 34 age-matched healthy controls, there was no significant difference in the prevalence rates for Bartonella between the affected and control cats (Dowers and Lappin 2005). PCR testing for Bartonella was performed on oral biopsy samples from 18 of the affected cats; Bartonella was identified in only one sample.

Treatment

Mild to moderate cases of gingivostomatitis may benefit from regular dental assessment and treatment (with extraction of all diseased teeth) as well as daily home dental care. There is some evidence that dental hygiene chews may be beneficial (Gorrel, Inskeep et al. 1998; Ingham, Gorrel et al. 2002). Oral hygiene products such as zinc ascorbate gel may also be helpful (Clarke 2001). The most common bacteria found in cats with gingivitis are gram-negative anaerobes (Harvey, Thornsberry et al. 1995). Metronidazole (30-60 mg/kg, divided BID, 7-10 days) or clindamycin (5 mg/kg, BID, 10 days or longer) may help with control of anaerobic flora. Metronidazole has the added advantage of having anti-inflammatory effects. Pulse-dosing of antimicrobials is controversial as studies demonstrating efficacy have not been performed, and concerns exist with regard to the potential for development of antimicrobial-resistant pathogens. The use of corticosteroids is also controversial, especially since significant adverse effects (including diabetes mellitus) can occur in cats on long-term treatment. Pain control may be achieved with non-steroidal anti-inflammatory drugs such as meloxicam or oral buprenorphine.

Chronic gingivostomatitis is often refractory to treatment. No conservative treatment, including professional dental assessment and treatment, home care, antibiotics, or corticosteroids, is likely to provide long-term (>6 months) resolution for moderate to severely affected cats. One small study of 8 cats with stomatitis found 50% responded to treatment with cyclosporine in a 6-month monitoring period (Vercelli, Raviri et al. 2006). The effect of bovine lactoferrin for the treatment of intractable stomatitis was evaluated in 4 FIV-positive and 3 FIV-negative cats (Sato, Inanami et al. 1996). The product was applied topically to the oral mucosa at 40 mg/kg daily for 14 days. Improvement was noted in pain response, salivation, appetite, and oral inflammation. Carbon dioxide laser ablation of diseased tissue has been advocated for disease control, pain relief, and preservation of non-diseased teeth, but published data on efficacy is scarce (Lewis, Tsugawa et al. 2007).

The only treatment shown to provide long-term relief in a majority of cats with moderate to severe disease is partial (all teeth behind the canines) or whole mouth dental extractions with excision of proliferative tissue. Confirmation that all tooth roots and remnants have been removed should be obtained with intraoral radiographs. In the only published study on the efficacy of dental extractions for chronic gingivostomatitis, 60% of cats had significant improvement, 20% had some improvement, and 20% had little or no improvement (Hennet 1997). A recent case report details the use of recombinant feline interferon omega (Virbagen Omega®, Virbac) in a cat with refractory gingivostomatitis after extraction of all molars and premolars (Southerden and Gorrel 2007).

References

Clarke, D. E. (2001). "Clinical and microbiological effects of oral zinc ascorbate gel in cats." J Vet Dent 18(4): 177-83.

Dowers, K. L. and M. R. Lappin (2005). "The association of Bartonella species infection with chronic stomatitis in cats (abstract)." J Vet Intern Med 19(3): 471.

Glaus, T., R. Hofmann-Lehmann, et al. (1997). "Seroprevalence of Bartonella henselae infection and correlation with disease status in cats in Switzerland." J Clin Microbiol 35(11): 2883-5.

Gorrel, C., G. Inskeep, et al. (1998). "Benefits of a 'dental hygiene chew' on the periodontal health of cats." J Vet Dent 15(3): 135-8.

Harvey, C. E., C. Thornsberry, et al. (1995). "Subgingival bacteria--comparison of culture results in dogs and cats with gingivitis." J Vet Dent 12(4): 147-50.

Healey, K. A., S. Dawson, et al. (2007). "Prevalence of feline chronic gingivo-stomatitis in first opinion veterinary practice." J Feline Med Surg.

Hennet, P. (1997). "Chronic gingivo-stomatitis in cats: long-term follow-up of 30 cases treated by dental extractions." J Vet Dent 14(1): 15-21.

Ingham, K. E., C. Gorrel, et al. (2002). "Effect of a dental chew on dental substrates and gingivitis in cats." J Vet Dent 19(4): 201-4.

Knowles, J. O., R. M. Gaskell, et al. (1989). "Prevalence of feline calicivirus, feline leukaemia virus and antibodies to FIV in cats with chronic stomatitis." Vet Rec 124(13): 336-8.

Lewis, J. R., A. J. Tsugawa, et al. (2007). "Use of CO2 laser as an adjunctive treatment for caudal stomatitis in a cat." J Vet Dent 24(4): 240-9.

Lommer, M. J. and F. J. Verstraete (2003). "Concurrent oral shedding of feline calicivirus and feline herpesvirus 1 in cats with chronic gingivostomatitis." Oral Microbiol Immunol 18(2): 131-4.

Lund, E., P. Armstrong, et al. (1999). "Health status and population characteristics of dogs and cats examined at private veterinary practices in the United States." J Amer Vet Med Assoc 214(9): 1336-1341.

Quimby, J. M., T. Elston, et al. (2008). "Evaluation of the association of Bartonella species, feline herpesvirus 1, feline calicivirus, feline leukemia virus and feline immunodeficiency virus with chronic feline gingivostomatitis." J Feline Med Surg 10(1): 66-72.

Sato, R., O. Inanami, et al. (1996). "Oral administration of bovine lactoferrin for treatment of intractable stomatitis in feline immunodeficiency virus (FIV)-positive and FIV-negative cats." Am J Vet Res 57(10): 1443-6.

Southerden, P. and C. Gorrel (2007). "Treatment of a case of refractory feline chronic gingivostomatitis with feline recombinant interferon omega." J Small Anim Pract 48(2): 104-6.

Vercelli, A., G. Raviri, et al. (2006). "The use of oral cyclosporin to treat feline dermatoses: a retrospective analysis of 23 cases." Vet Dermatol 17(3): 201-6.