White Piedra, a Rare Superficial Mycosis: an Update

Antifungal susceptibility profile of Trichosporon inkin: About three cases of White Piedra

Trichosporon spp. usually cause systemic or superficial infections. Three cases of White Piedra produced by Trichosporon inkin are described. The in vitro antifungal activity to fluconazole, amphotericin B, ketoconazole and caspofungin against the three clinical isolates were evaluated. Sensitivity to fluconazole and ketoconazole was evidenced. However, the treatment of this mycosis is still a challenge.

White Piedra: An Uncommon Superficial Fungal Infection of Hair

White piedra is a superficial fungal infection of hair caused by Trichosporon species. It presents clinically as white nodules encasing the hair shafts and may lead to increased fragility. It can usually be differentiated easily from clinically similar conditions based on clinical and microbiologic features. We report a case of white piedra of scalp hair in a 32-year-old female caused by T. ovoides, diagnosed using clinical, trichoscopic, microbiologic and molecular methods. In this case, trichoscopy acted as an interface between clinical and microbiologic examination, obviating the need for hair shaft microscopy. The genus Trichosporon contains 6 species of clinical significance viz., T. asahii, T. asteroides, T. cutaneum, T. inkin, T. mucoides, and T. ovoides, which cannot be differentiated based on their morphologic characteristics. A genotypic identification using molecular methods helped determine the causative species. It was treated successfully with oral itraconazole and topical ketoconazole.

Efficacy of topical vs combined oral and topical antifungals in white piedra of the scalp

BACKGROUND

Topical antifungals are the most commonly used therapy in white piedra of the scalp. However, persistence and relapse of infection still pose a significant challenge. Systemic antifungals have been recommended to enhance the therapeutic response.

AIMS

To compare the efficacy of topical antifungal alone versus combined topical and oral antifungals in the treatment of white piedra of the scalp.

METHODS

Sixty patients with white piedra of the scalp were divided into 3 groups, each containing 20 patients. Group A received topical clotrimazole, group B received combined topical clotrimazole and oral itraconazole, and group C received combined topical clotrimazole and oral terbinafine. The treatment was continued until clearance of infection was confirmed by dermoscopic and mycological examination. Positive responders were followed up for 3 months after treatment.

RESULTS

All the patients achieved complete clearance of infection. The median treatment time in group B was significantly shorter than group A (P < .001) and group C (P < .001), respectively. In addition, the median treatment time in group C was significantly shorter than group A (P = .002). No recurrence of infection was noted during follow-up period.

CONCLUSION

The three modalities were effective in the treatment of white piedra of the scalp. The most rapid response was observed with the combined use of topical and oral azoles.