You are here: 
text zoom : S | M | L
Printer Friendly Version
Further Enquiries

School of Molecular & Biomedical Science
The University of Adelaide
AUSTRALIA 5005

Contact:
Dr David Ellis
Email


White piedra

Description:

White piedra is a superficial cosmetic fungal infection of the hair shaft caused by Trichosporon beigelii. Infected hairs develop soft greyish-white nodules along the shaft. Essentially no pathological changes are elicited. White piedra is found worldwide, but is most common in tropical or subtropical regions.

Clinical manifestations:

Infections are usually localised to the axilla or scalp but may also be seen on facial hairs and sometimes pubic hair. White piedra is common in young adults. The presence of irregular, soft, white or light brown nodules, 1.0-1.5 mm in length, firmly adhering to the hairs is characteristic of white piedra.

Laboratory diagnosis:

1. Clinical Material: Epilated hairs with white soft nodules present on the shaft.

2. Direct Microscopy: Hairs should be examined using 10% KOH and Parker ink or calcofluor white mounts. Look for irregular, soft, white or light brown nodules, 1.0-1.5 mm in length, firmly adhering to the hairs.

3. Culture: Hair fragments should be implanted onto primary isolation media, like Sabouraud's dextrose agar. Colonies of Trichosporon beigelii are white or yellowish to deep cream colored, smooth, wrinkled, velvety, dull colonies with a mycelial fringe.

4. Serology: Not required for diagnosis.

5. Identification: Characteristic clinical, microscopic and culture features.

Causative agents:

Trichosporon beigelii

Management:

Shaving the hairs is the simplest method of treatment. Topical application of an imidazole agent may be used to prevent reinfection.

Further reading:

Ajello L and R.J. Hay. 1997. Medical Mycology Vol 4 Topley & Wilson's Microbiology and Infectious Infections. 9th Edition, Arnold London.

Kwon-Chung KJ and JE Bennett 1992. Medical Mycology Lea & Febiger.

Rippon JW. 1988. Medical Mycology WB Saunders Co.