White piedra is an uncommon yeast infection of the hair. Several species of a fungus that live in soil or dirty water can cause white piedra.

Piedra is the Spanish word for stone. White piedra appears as white or light brown stones that loosely attach to the tip of a hair shaft and may group to form clusters. The stones, which people sometimes call concretions or nodules, feel gritty and are easy to remove.

White piedra occurs more often in warm and tropical regions of the world, such as South America, Africa, and the southeastern United States. The infection can affect people of all ages, genders, and ethnicities.

Although white piedra is a relatively harmless condition, without treatment, it can lead to brittle and damaged hair. People can treat it by shaving the affected area and applying an antifungal medication.

In this article, we provide images of white piedra. We also examine the symptoms, causes, and treatment of the condition.

The main symptom of white piedra is the formation of clusters of tiny nodules along the hair shafts.

These rock-like structures appear white, gray, or tan. The stones are soft, feel gritty to the touch, and are easy to remove. However, removal may cause the affected hair shafts to split or break.

White piedra may develop on any area of hair on the body, such as:

  • scalp hair
  • eyebrows and eyelashes
  • beard
  • mustache
  • underarm hair
  • pubic hair

It is easy to confuse white piedra with other skin and hair conditions. However, there are some key differences between them.

  • Head and body lice and their shell casings — known as nits — may resemble white piedra stones. However, nits are not as easy to remove as white piedra stones, and lice cause severe itching while white piedra does not. Also, with a lice infection, small white bugs that resemble crabs may be visible to the naked eye.
  • Ringworm is a fungal infection of the scalp that appears as a scaly, itchy, ring shaped bald patch.
  • Trichomycosis is the colonization of bacteria in the sweat glands. It causes yellow or red concretions with a rancid odor.
  • Monilethrix is a rare genetic hair shaft defect that gives the hair a beaded appearance and results in patches of hair loss.
  • Dandruffcauses a dry, flaky, itchy scalp. White flakes often fall from the scalp onto a person’s face and clothing. Conversely, white piedra remains in the affected area.
  • Black piedra is similar to white piedra, but the stones on the hair shafts are brown-black and challenging to remove. Black piedra mainly affects the hair on the scalp, whereas white piedra can affect all areas of hair on the body.
  • Hair casts are white, narrow, and cylinder-shaped structures. While hair casts encircle the hair shaft, white piedra does not. Hair casts slide easily along the hair shaft and do not result in hair breakage or damage.

A species of fungus called Trichosporon causes white piedra. Trichosporon fungi occur widely in nature, particularly in soil, lake water, and plants. The fungus can also be present in:

  • air
  • rivers or stagnant water
  • vegetation
  • human and animal skin or stool
  • sewage

White piedra can spread to people when they come into contact with contaminated:

  • water
  • soil
  • plants
  • animals

The spread of white piedra directly from person to person is uncommon. However, it is possible to transmit the infection in the genital region through sexual activity.

After a person is exposed, the fungus needs the right conditions to survive and colonize human hair.

Practices that can lead to colonization and result in white piedra infection include:

  • infrequent bathing or poor personal hygiene
  • bathing in stagnant water
  • frequent use of oil applications to the hair
  • irregular combing habits or matted hair
  • covering wet hair with a veil or turban

White piedra is more common in temperate and semitropical climates. These areas include:

  • South America
  • Africa
  • Europe
  • Middle East
  • Southeast Asia
  • India
  • Japan
  • southeastern United States

Additional risk factors for getting a white piedra infection include:

  • inability to wash or bathe frequently
  • working in unsanitary conditions
  • excessive sweating
  • poor personal hygiene
  • long hair

Most reports of white piedra have been in children and young adults, particularly females who regularly wear headbands. Also, women who immediately tie and cover wet hair and their scalp with a veil have a higher chance of developing white piedra.

Individuals who suspect that they have white piedra should see a doctor.

A doctor can diagnose white piedra by conducting a physical examination. They may also recommend microscopic testing of the affected hair to confirm a diagnosis.

Shaving the affected area is the preferred treatment for white piedra. Medicated shampoos and lotions may be effective when shaving is not an option for cosmetic, personal, or cultural reasons.

A person can treat white piedra with antifungal lotions and creams. Options may include:

  • clotrimazole 1%
  • miconazole 2%
  • ketoconazole 2% shampoo or lotion
  • ciclopirox
  • selenium sulfide 2%

Topical medications do not work for some individuals. A doctor may prescribe an oral antifungal medication, such as itraconazole or terbinafine, to treat persistent white piedra infections.

White piedra of the genitals often recurs, so combining shaving with a short course of a topical antifungal is often necessary for a complete cure.

The fungus may remain in clothing and bedding. A person should throw infected underwear away and disinfect other garments, linen, and towels to help prevent reinfection.

Home remedies

There are no effective home remedies for treating white piedra. This type of hair infection requires medical evaluation and antifungal medication.

White piedra infections will often come back, especially when they can pass between family members. Reinfection is usually the result of sharing combs, hair products or accessories, pillows, and linens.

Several measures can help prevent a person from both initial infection and reinfection with white piedra. These measures include:

  • avoiding sharing brushes, combs, and other hair accessories
  • wearing loose cotton underwear and changing twice if prone to excessive perspiration during the summer months or in humid conditions
  • using aluminum chloride hexahydrate (Drysol) to help minimize excessive sweating
  • drying the skin and hair thoroughly after bathing
  • drying the scalp hair completely before tying, wrapping, or covering the hair
  • cleaning all clothing, bedding, and towels that come into contact with the affected areas of hair

White piedra is a rare superficial fungal infection of the hair shaft. It can affect people of any age and tends to occur in temperate regions of the world.

Shaving the affected area and completing a short course of a topical antifungal can treat white piedra.

Following good personal hygiene and hair care practices can help prevent future recurrences of white piedra.