What are Rodent Ulcers?

Rodent ulcers are ulcers which appear around the lips and face. Historically, people thought that they were the result of bites from rodents, explaining the name. In fact, rodents are not involved with this type of ulceration, which is better known as an eosinophilic ulcer, because it is characterized by the presence of eosinophils. This skin problem can arise in response to a variety of problems, including underlying disease processes and trauma, and it is important to have it evaluated by a doctor.

Cats are prone to developing rodent ulcers, usually as a result of trauma to the face. The damaged area becomes inflamed, blood cells known as eosinophils flood the area, and an eosinophilic ulcer develops. The ulcer can be treated with steroid medications to reduce the size, and monitoring to check for any signs of changes. Ulcers can be found on the nose, around the lips, and inside the lip, and they may cause considerable discomfort to the animal.

In cats, rodent ulcers can sometimes be a sign of a problematic underlying disease process such as the feline leukemia virus. For this reason, it is important to take a cat to a veterinarian when an ulceration appears around the lips or face, so that the vet can examine the ulcer and take a sample for examination in a pathology laboratory. A pathologist can determine the origins of the ulcer and check for signs that it is associated with a serious medical problem.

In humans, rodent ulcers can also be linked with cancers. Some cancers cause an increase in eosinophil levels, which can make people more prone to developing rodent ulcers. A rodent ulcer can be diagnosed by taking a swab of the ulcer and examining it under a microscope; the presence of eosinophils is a giveaway sign. As with cats, in human patients, it is important to find out what caused the ulcer, as this may influence the approach to treatment.

Like other ulcerations, rodent ulcers should be well cared for. The break in the skin can create an opportunity for infectious agents to enter the body, making the ulcer worse and potentially creating complications for the patient. During the healing process, such ulcers can be gently washed with soap and warm water and patted dry after cleaning. They should be covered up with makeup, as this can cause irritation; people who find a rodent ulcer unsightly can cover it with a bandage.