Gingivitis, stomatitis, and other oral lesions in cats (Proceedings)
Disease of the oral cavity is a common problem, particularly in middle-aged to older cats. Some disorders (e.g. lymphoplasmacytic gingivitis/stomatitis) may begin very early in life in some purebred cats. This presentation will not delve into the area of primary dental disease although dental lesions may be associated with some of these disorders. There are usually no specific clinical signs for any of these disorders but a number of signs are common to them all. These include halitosis, ptyalism (drooling), difficulty eating (food falls from mouth or refusal to eat dry food), anorexia, gagging, sneezing, nasal discharge and/or sneezing, and pain on opening the mouth.
Lymphoplasmacytic gingivitis/stomatitis (LPS)
The underlying etiology of this disorder is not known. Most scientific evidence has pointed to the role of calicivirus and possibly herpesvirus in initiating and perpetuating these inflammatory changes. Other theories suggest that the lesions arise from an immune-mediated reaction of the body to the tissues of gingival attachment to the teeth. This, however, does not explain the severe lesions seen in the fauces of the mouth in some cats. A recent theory to be advanced is that LPS is caused by Bartonella henselae. There is, to date, no published scientific evidence to support this contention. The fact that LPS lesions do not resolve with antibiotics alone is further evidence for a cause other than bacterial infection.LPS occurs most frequently in middle-aged to older cats. However, some purebreeds such as Abyssinian, Somali, and others, may have LPS gingivitis starting as early as 6 months of age. The breeders are aware of this condition and many consider "red gum" to be normal for their breeds of cats. Lesions may occur along the gingival margins and when present in this location, may be associated with underlying FORL lesions. If FORLs are presently, they may be overgrown by the proliferative gingival tissue so these areas must be examined carefully. Many of the more severely affected cats will have very proliferative and painful hyperplastic tissue in the fauces of the mouth. Lesions are usually bilateral which will help to distinguish this condition from neoplasia. Occasionally, polyp-like lesions can be found in the internal commissures of the lips.
Complete blood counts are usually normal in affected cats unless other concurrent disorders are present. A biochemistry profile often reveals hyperproteinemia with hyperglobulinemia. This is probably due to the immunologic reaction and lymphoid proliferation in this condition. FeLV and FIV are not significantly associated with LPS but testing for all cats with oral disease is recommended. The diagnosis is suspected by the history and clinical appearance of the lesions. However, definitive diagnosis should be made by biopsy of affected tissue. Be sure to get a biopsy deep enough to get to the heart of the lesions rather than just the most superficial, secondarily infected portions of the lesions.
Treatment of LPS is frustrating because there is no one approach to treatment that will be effective for all cats. If there is significant dental disease and/or FORLs, this should be managed first. If the LPS tissue is very proliferative and impairing eating, swallowing, or interfering with medication it should be resected with electrosurgery (radiosurgery) or laser. Care should be used to avoid damaging tooth roots during gingival resection. Other recommendations for management include using ceramic or metal food bowls (avoid plastic), and feeding a limited antigen or hypoallergenic diet. Bovine lactoferrin (Allergy Research Group – see HerbsMD, http://www.herbsmd.com/ and other internet nutraceutical suppliers) applied topically in the oral cavity (350 mg/day) has improved some cats with LPS and LPS associated with FIV. Lactoferrin appears to inhibit infection of cells with feline calicivirus thus adding additional support for the role of this agent in causing LPS. (J Appl Microbiol 95:1026-1033, 2003). Although herpesvirus isn't usually the main cause for this disorder, oral lysine (500 mg PO q12h) can be given. Various antibiotics have shown some benefit including metronidazole and azithromycin. Doxycycline has some anti-inflammatory effects on matrix metalloproteinases (MMPs) and may be useful in some cats. Corticosteroids are often the cornerstone of therapy for LPS. Oral administration is recommended. Repositol steroids can be used if the mouth is too painful for owners to medicate the cat. For resistant cases, chlorambucil (1 mg PO q24h, or 2 mg PO q48h) can be used to combat the lymphoid proliferation. Doses of both of these latter two medications should be tapered as the condition responds. Recently, cyclosporine has been used successfully to control oral lesions when steroid use is contraindicated due to a concurrent medical condition or if steroid side-effects are unacceptable. Often a combination of various approaches is required to bring this condition under control if possible. One practitioner has reported some success with pentoxifylline (Trental) at 100 mg (¼ tablet) PO q12h. Pain management should be considered an important part of therapy for this and other painful oral conditions. Control of pain will make eating more comfortable for the cat and medicating much easier for the owner. Useful drugs include meloxicam suspension (0.1 mg TOTAL dose, PO, q24-72h) [do NOT use NSAIDs if concurrently on corticosteroids], tramadol, or sublingual buprenorphine. Full mouth extraction of all teeth as recommended by some veterinary dentists is a very traumatic procedure and rarely resolves fauces lesions.