Find information on medical topics, symptoms, drugs, procedures, news and more, written in everyday language.

* This is the Consumer Version. *

Overview of Fungal Skin Infections

by Denise M. Aaron, MD

Fungi usually make their homes in moist areas of the body where skin surfaces meet: between the toes, in the genital area, and under the breasts. Common fungal skin infections are caused by yeasts (such as Candida—see Candidiasis) or dermatophytes, such as Epidermophyton, Microsporum, and Trichophyton (see Overview of Dermatophytoses (Ringworm, Tinea)). Many such fungi live only in the topmost layer of the epidermis (stratum corneum) and do not penetrate deeper. Obese people are more likely to get these infections because they have excessive skinfolds. People with diabetes tend to be more susceptible to fungal infections as well.

Strangely, fungal infections on one part of the body can cause rashes on other parts of the body that are not infected. For example, a fungal infection on the foot may cause an itchy, bumpy rash on the fingers. These eruptions (dermatophytids, or identity or id reactions—see Dermatophytid Reaction) are allergic reactions to the fungus. They do not result from touching the infected area.

Doctors may suspect a fungal infection when they see a red, irritated, or scaly rash in one of the commonly affected areas. They can usually confirm the diagnosis by scraping off a small amount of skin and having it examined under a microscope or placed in a culture medium where the specific fungus can grow and be identified (see Culture).