There’s a Fungus Among Us: Fungal Infections in Pets

While a toadstool may come to mind when you think about fungus, most of the fungal organisms around us are actually microscopic. While many are harmless, sometimes fungal infections in pets can turn serious. Read on to learn about what happens when fungus becomes a problem.

On the Surface

One of the most common places that we run into fungus in our pet patients is on the skin. Yeast and other fungi actually live in small amounts on our pet’s skin (and ours). This is normal, as they are part of the healthy skin flora.

Any time the skin’s normal function is disrupted, however, changes in the flora occur. This can result in an overgrowth or an opportunity for an infectious fungus to make its way in. These fungal infections can occur anywhere on the skin or in the ears. Yeast, in particular, often carries a characteristic odor.

Common fungal infections we see on the skin include:

Malassezia dermatitis – This yeast organism lives on our pet’s skin all the time, but may spiral out of control in the right conditions. Malassezia overgrowth is often itchy and smelly. It most often occurs in the external ear canal as part of an ear problem, but can affect any part of the body. Chronic yeast overgrowth often results in thick, elephant-like skin.

Ringworm – Ringworm is not actually a worm at all, but rather a fungus. There are several types of ringworm, which can be picked up from an infected, shedding animal or in the environment. These do not often itch, but can result in hair loss and scales on the skin.

Treating a fungal infection on the skin is often twofold. If there is an underlying cause for the overgrowth, such as a skin allergy or immunosuppressive condition, we will need to treat it appropriately. After that, we must also do our best to control the fungal growth. Topical therapies like antifungal lotions or shampoos may be helpful in some instances, whereas systemic medications may be needed in others, such as with widespread ringworm infection.

Systemic Fungal Infections in Pets

While fungus can be normal on the skin, it is never normal inside the body. Systemic fungal infections in pets can be quite serious. There are several that can occur, but the ones that we see most commonly in Texas include:

Valley Fever – This infection, caused by the soil-dwelling fungus Coccidiodes immitis, occurs when the fungal spores are inhaled, often leading to a lung infection. In some pets the fungal infection may travel to other parts of the body. This can lead to a wide range of symptoms, from joint problems to fever, and even seizures.

Histoplasmosis – Histoplasma capsulatum is a fungal organism found in bird and bat droppings. When the spores are inhaled, the lungs and local lymph nodes can become infected. Histoplasmosis also often affects the gastrointestinal system.

Cryptococcosis – This systemic fungal infection, caused by Cryptococcus neoformans found in pigeon droppings, can be contracted through inhalation or entry through wounds. It can spread throughout the body, but most often causes neurologic or ocular problems.

Systemic fungal diseases are quite harmful and notoriously difficult to treat. Aggressive treatment with systemic antifungals is the cornerstone of therapy.

Fungal infections in pets can range from easily treated to life-threatening. At Leon Valley Veterinary Hospital, we are equipped to help your pet no matter how big or small the problem. If you have concerns about your pet, please let us know right away.