Pet Files: Get active in ridding ringworm in your pet

West Ridge's own Dr Deb Singleton, wrote the following article about ringworm for the Greeley Tribune:

Ringworm is a fungal infection affecting the hair, nails and the superficial layers of the skin. The condition is called “ringworm” because of the classic red, circular lesions of hair loss that appear on the skin. Another name for the condition is “dermatophytosis,” which is a description of the type of fungus involved in the infection.

Exposure to the fungus usually occurs via the environment (soil or living area), or exposure to a carrier animal. Exposure does not necessarily lead to an infection. An affected animal that does not show signs may remain an inapparent carrier for a long period of time. Lack of good immune system function can lead to an infection. The condition is more common in long-haired cats and young animals. High population density, poor nutrition and poor environmental management can increase the risk of ringworm infection.

Lesions on the skin may begin as a poor appearance to the hair coat and progress to circular areas of hair loss. Scales, redness and increased black pigmentation of the skin, as well as itchiness may also be seen. Humans are also susceptible to ringworm infection, and may develop similar red, circular lesions on the skin.

Diagnosis of a ringworm infection may be difficult. The best method of confirming a diagnosis is to culture hairs plucked from the edge of an area of hair loss; these are placed on a special gel media. The media will change color from yellow to red with the growth of a fungus. This process generally takes two to three weeks. Hair examined with a special UV light may glow green, increasing the suspicion of ringworm, but this test is not diagnostic, as skin flakes and sebum may also produce a false positive glow. Rarely, a skin biopsy may be required.

Many short-haired cats and dogs will undergo spontaneous remission or cure of the condition. Treatment may be frustrating and somewhat expensive in multi-animal households or recurrent cases. Environmental treatment is important; cleansing with diluted bleach (90 seconds with water) is an effective method of disinfecting surfaces and bedding.

Medical treatment may range from topical solutions and shampoos to oral medications. Generally, mild cases will be treated by cleansing the animal with miconazole (anti-fungal) shampoo and applying a topical anti-fungal medication with gloves to the lesions. It is important not to apply any medication with bare hands, or to handle the animal unnecessarily, as this will increase the likelihood of spread of the infection to humans.

Oral anti-fungal medications may be used in more severe or generalized cases. These include itraconazole, ketoconazole and griseofulvin. These medications should be given with a meal to improve absorption. They may have side effects, ranging from mild stomach upset to severe liver or bone marrow reactions, so they are used cautiously. Your veterinarian may require blood testing to ensure that your animal is able to take these medications safely.

A negative subsequent dermatophyte culture is the only way to ensure a response to therapy. Many animals will appear to improve, but remain positive on culture. Treatment is generally continued until at least one culture is negative.

Please speak with your veterinarian if you have questions about ringworm infection in your pet. If you suspect that a family member may have ringworm, please consult your medical doctor.

Debra Singleton is a veterinarian practicing in Greeley. She is a graduate of Colorado State University specializing in the treatment of dogs, cats and exotic animals.