What Is Trichomycosis?

Medically Reviewed by Carol DerSarkissian, MD on February 20, 2024
3 min read

Trichomycosis is a common bacterial infection that affects your skin and hair. It often goes unnoticed because it has no obvious symptoms and doesn’t cause pain.

This skin condition is most likely to begin in your armpit. But it may flare up in any area of the body where hair grows, like your scalp or genitals. 

You’ll probably smell it before you see it. You might find yourself scratching or feeling uncomfortable in the affected area, too.

Trichomycosis doesn’t present a serious health threat. But you should take steps to deal with it to prevent any side effects or long-term discomfort.

In trichomycosis, a white or yellow substance — or red or black in more extreme cases — covers individual hairs. It may also change the texture of the affected hairs.

The substance forms a film that feels almost wax-like. It’s made up of bacteria that stick to each hair — starting at the base and then covering it completely.

If you notice a strange odor, color change, or textured hair follicles in the area, see a doctor.

Your dermatologist can tell whether you have the condition by using several methods, including:

  • Wood’s light. If you have trichomycosis, the bacteria glow when the affected part is exposed to a UV light.
  • Direct microscopy. Samples from the infection site are viewed under a microscope.
  • Dermoscopy. Using a magnifying lens, your doctor examines the surface of your skin.

A few possible causes of trichomycosis have been identified.

Poor hygiene, obesity, and excessive sweating are common contributors to trichomycosis. Generally, any circumstance or habit that allows bacteria to build up on the hair follicles can cause or worsen the infection.

Because women tend to remove more hair (by shaving, waxing, etc.) than men, trichomycosis is more often seen in men.

Young adults and people who live in humid, tropical climates have a higher chance of getting trichomycosis.

Trichomycosis is often found along with conditions called erythrasma and pitted keratolysis, which can both increase discomfort in the affected areas.

Erythrasma. Erythrasma is another skin condition commonly found in humid climates, often among people with poor hygiene, obesity, and excessive perspiration. The infection is not related to hair, but it is often found in skin folds where trichomycosis happens, like the armpit and inner thigh. Erythrasma appears as pink, red, or brown patches that become scaly and wrinkly over time.

Pitted keratolysis. Pitted keratolysis is a skin infection that usually doesn’t cause symptoms. Small indentations, or “pits,” appear in areas where the condition has settled, and you may have itching or tenderness. Its causes include extreme sweating combined with tight-fitting clothing, like wearing tight socks while running.

Treating trichomycosis can be difficult because of how easily it spreads. Infection happens when bacteria come into contact with hair follicles. The bacteria stick to the surface of new pieces of hair, forming a strong connection that can’t be broken using plain water or common cleansers.

Regular hair removal, like shaving or waxing, in the affected area for at least two to three weeks can stop the bacteria from spreading and help remove it from your body. The infection can also be treated with medicated creams or body washes containing certain ingredients, such as sulfur soap.