White Piedra: Clinical, Mycological, and Therapeutic Experience of Fourteen Cases.

Background: White piedra (WP) is an asymptomatic superficial mycosis that affects the hair stems, forming whitish nodules caused by various species of the genus .

Objective: To present a case series of WP of the head, its epidemiological data, as well as clinical, mycological, and therapeutic experience.

Methods: We conducted a 12-year retrospective and observational study of WP cases tested by dermoscopy, mycological study, and the identification of species through morphology, biochemistry, and proteomics (matrix-assisted laser desorption/ionization time-of-flight mass spectrometry). The treatment was based on ketoco-nazole shampoo as well as keratolytics.

Results: We included 14 cases of WP, all located in the head and 1 case with both head and scrotum affected. Nine cases (64.3%) presented in children aged < 15 years. The majority of the cases (13/14, 92.8%) were women. Two cases were associated with hyperkeratosis and intertrigo. Most patients had long hair and excessive moisture. In all cases hair nodules were observed and (11/14, 78.6%) was usually isolated. Eleven cases (78.6%) were cured by administering 2% ketoconazole shampoo.

Conclusion: WP was observed in school-age girls. The diagnosis was based on the observation of hair nodules and its main etiologic agent was , with good response to treatment in most cases.