White piedra is a relatively rare fungal infection of the hair shaft. It is caused by a yeast-like fungus called Trichosporon. The two types of fungus that cause white piedra are T. inkin and T. ovoides. White piedra is generally not contagious.
The primary symptoms of white piedra are white-to-tan gelatinous, pearly nodules surrounding the hair shaft. These nodules are typically found in facial hair and body hair (for example, in mustaches and beards, on eyelashes and eyebrows, and in armpit and pubic hair). The nodules are about 1mm or greater in diameter and are fairly easy to remove.
Other symptoms of white piedra include:
- Brittle, broken hair
- Hair that feels gritty
- Pain or itching
White piedra | Image source: Photo: dermaamin.com
White piedra can occur in any age group and in both sexes, but young men seem to be most at risk. The condition is most prevalent in humid-to-temperate climates. In the United States, most incidences occur in the South, although some cases have also been documented in the Northeast.
How does it differ from other conditions?
White piedra can be confused with other conditions that affect the hair. Here’s how white piedra differs from other hair or scalp conditions:
Lice vs. white piedra
Lice are small, non-flying insects that attach to the hair shaft and suck blood from the scalp. Lice eggs (called nits) are dark colored, but hatched lice are light in color. Unlike lice, white piedra will not produce a severely itchy sensation or make you feel like something is crawling along your head. White piedra nodules are easy to remove while lice nits are not.
Black piedra vs. white piedra
Black piedra is a cousin to white piedra. The nodules that characterize black piedra are hard, black/brown in color, and difficult to remove. Black piedra is more commonly seen in scalp hair and not facial or body hair.
Tinea versicolor vs. white piedra
Tinea versicolor is a fungal skin infection caused by yeast. People with this condition can get scaly patches anywhere on their body. These patches can be lighter or darker than your natural skin color. Unlike these skin patches, white piedra appears as nodules around the hair shaft that are a white-to-tan in color.
Dandruff vs. white piedra
Dandruff is a condition that affects the scalp, while white piedra affects the hair shaft.
The technical cause of white piedra is a fungus of the trichosporon variety. This fungus is found mostly in soil. It is not clear how people get this infection but it may be that people who get white piedra already have the trichosporon fungus on their skin.
How is it diagnosed?
Doctors diagnose white piedra by examining the hair shaft and the nodules. They may also perform tests on the fungus to help pinpoint their diagnosis.
The first line of treatment is to completely shave off all infected hair. Doing so may be sufficient to rid yourself of the fungus. Other treatment options include antifungal creams, shampoos, and oral antifungal medications.
The most common complication of white piedra is hair loss and/or brittle hair. People who are immunosuppressed (who have HIV or are undergoing chemotherapy), can have pruritic (characterized by a burning sensation) or necrotic (consisting of dead tissue) nodules or papules. These can cause intense itching and discomfort.
While shaving infected hair is the first line of defense, the condition does respond well to topical and oral antifungal treatments, usually used for just a few weeks. For the most part, white piedra is a harmless condition and most people will recover with few if any health consequences. They will also go on to grow healthy hair.