Although you may think you only need to check for plaque and tartar accumulation on their teeth, pets can suffer from a whole host of oral issues. Autoimmune diseases are conditions that pop up when the body’s immune system creates an abnormal response to perfectly normal substances, like plaque. Here are a few of the most common autoimmune diseases that can affect your furry pal’s mouth.

Stomatitis in dogs

Canine stomatitis involves inflammation of the mucous membranes of the mouth, such as the gums and inner cheek surfaces. Signs include:

  • Severe gum inflammation
  • Receding gums in multiple sites
  • Large sores on the mucous membranes near large teeth (e.g., canines, carnassials)

This condition’s characteristic feature is a contact ulcer or sore that develops where the lip contacts the tooth surface. Most commonly, these ulcers, termed kissing ulcers, develop on the upper lip next to the canine or carnassial teeth where the lips “kiss” the teeth.

Canine stomatitis commonly affects greyhounds, but can also be seen in Maltese terriers, miniature schnauzers, Labrador retrievers, and other breeds. Signs will appear when the immune system mounts an excessive inflammatory response to dental plaque, which means plaque control is critical for keeping affected pets comfortable. Regular professional dental cleanings and twice-daily toothbrushing at home can help minimize signs, but some pets may need the problematic teeth extracted if their mouth is too painful for toothbrushing. Yet, extraction may help control ulcer formation, but may not completely cure the issue, as plaque grows on all the mouth’s surfaces, not only the teeth.

Stomatitis in cats

Cats can also develop stomatitis, which is seen more commonly in cats than dogs. Cats with feline stomatitis have progressively worsening inflammation of the mouth, gums, and upper throat, and may have extensive sores that cover all the inside surfaces. Signs you may see if your cat develops stomatitis include:

  • Severe pain when opening their mouth
  • Bad breath
  • Excessive drooling
  • Difficulty swallowing
  • Food avoidance

While the cause has not been proven, feline stomatitis appears to be an excessive, inappropriate inflammatory response to plaque in the mouth. However, many affected cats also harbor calicivirus organisms, which may be an instigating factor. Surgical removal of teeth and the connective tissue that attaches teeth to the jawbone is the only treatment that will provide some measure of improvement and long-term control. Some cats may need all their teeth extracted for comfort, but being toothless doesn’t appear to slow them down. In fact, cats often begin eating well only a day or two following surgery. For the best results, extractions should be performed early in the disease process, to ensure the gum tissue is as healthy as possible for extraction site closure.

Pemphigus conditions in dogs and cats

Pemphigus is an autoimmune skin disease in which the body’s immune system attacks the connections between its own skin cells. Each pemphigus type differs, because each has a different target antigen or histopathologic feature. Pemphigus foliaceus is the most common type in cats and dogs, and generally appears as crusted skin lesions, but ulcers can also form on the gums and lips. Pemphigus vulgaris has deeper, more severe ulcers than other pemphigus forms, and can be particularly painful for pets.

Causes of pemphigus diseases, whether they affect only the skin, or the mouth as well, include:

  • Underlying medical conditions (e.g., chronic skin allergies, cancer)
  • Viral infections
  • Ultraviolet light exposure
  • Drug reactions
  • Immune system defect
  • Breed (e.g., in cats, domestic shorthair or longhair, Siamese, Himalayan, Persian, Maine coon, American blue, Somali, Scottish fold, ragamuffin; in dogs, Akita, chow chow, bearded collie, dachshund, Doberman, Newfoundland)

Pemphigus diagnosis requires a skin biopsy. Once confirmed, treatment will consist of immune system suppression. Pets with pemphigus require long-term, sometimes lifelong, therapy to control the disease. 

Systemic lupus erythematosus in dogs

Systemic lupus erythematosus (SLE) is an immune-mediated disease in which a dog’s immune system begins to attack their own tissues. This disease is rare in cats and uncommon in dogs, although some canine breeds, including the Afghan hound, beagle, collie, German shepherd, Irish setter, Nova Scotia duck tolling retriever, Old English sheepdog, poodle, and Shetland sheepdog, are predisposed to SLE development. 

Signs can appear suddenly, or subtly develop over time, depending on where the immune system is attacking the tissues. Skin signs may include redness, fur loss, localized ulceration, and pigment loss. Ulcers can also form at mucocutaneous junctions, which are areas where skin meets mucous membranes, like the lip edges. Prognosis is not good for pets with SLE, and treatment requires lifelong immunosuppression.

Masticatory myositis

Masticatory myositis is an inflammatory condition with an immune-mediated cause that affects the muscles used to chew. In acute cases, the masticatory muscles swell, making opening their jaw difficult for affected pets. Chronic cases are evident through appetite loss, weight loss, muscle wasting, and difficulty opening the jaw. Although the condition sometimes improves on its own, corticosteroid treatment is recommended in most cases. Relapses are common, and long-term medication may be required.

Immediately diagnosing and correctly treating autoimmune diseases of the mouth provide the best prognosis for your pet. If you notice unusual ulcers or lesions around your pet’s mouth, or if they have difficulty opening their jaw and eating, contact our Animal Dental Clinic team for an appointment, so we can help alleviate your pet’s painful condition.