Tinea nigra is an infection of the skin. It affects the outermost layer of skin. The infection will cause a black or brown patch on the skin. Except for the dark patch, tinea nigra is a harmless condition.
Tinea nigra usually affect the palms of the hands or soles of the feet. It may also appear on the neck or trunk.
|Cross-Section of Skin|
|Tinea nigra affects the outermost layer of skin.|
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Tinea nigra is caused by a fungus. The type of fungus that causes this infection is most often found in rotting wood, soil, compost, or sewage. The fungus may enter your body through a break in your skin.
You are more likely to develop tinea nigra if you have been living or traveling in tropical or subtropical areas, such as:
- South Africa
- Puerto Rico
- Coastal areas along the southeastern United States
Tinea nigra causes a brownish-black patch on the skin that:
- Has an irregular shape with a darker border
- May be itchy or scaly
- Tends to expand over time
A tinea nigra patch may be mistaken for a type of skin cancer. Talk to your doctor about any skin growth or changes.
Your doctor will ask about your symptoms and medical history. A physical exam will be done. You may need to see a skin specialist for tests, diagnosis, and treatment.
Tinea nigra is diagnosed by scraping a small sample of the affected skin. The sample is examined under a microscope.
Tinea nigra is usually treated with an antifungal medication. The medication is placed on the skin as creams or ointments.
To help reduce your chance of tinea nigra:
- Use care when traveling in high-risk areas.
- Avoid contact with potentially infected material, such as rotting wood, dirt, sewage, or compost.
- If you must work with any of the materials listed above, take the proper safety steps. Wear gloves and other protective gear.
American Academy of Dermatology https://www.aad.org
Family Doctor—American Academy of Family Physicians https://familydoctor.org
Health Canada https://www.canada.ca
The College of Family Physicians of Canada http://www.cfpc.ca
Gupta AK, Chaudhry M, Elewski B. Tinea corporis, tinea cruris, tinea nigra, and piedra. Dermatol Clin. 2003;21(3):395-400.
Mandel GL, Bennett JE, et al. (eds). Principles and Practice of Infectious Diseases. 6th ed. Philadelphia, PA: Elsevier, Inc.; 2005.
Tinea nigra. DermNet New Zealand website. Available at: https://www.dermnetnz.org/topics/tinea-nigra. Accessed December 5, 2017.
- Reviewer: EBSCO Medical Review Board David L. Horn, MD, FACP
- Review Date: 11/2018
- Update Date: 12/20/2014