White Piedra: An Uncommon Superficial Fungal Infection of Hair

Abstract

White piedra is a superficial fungal infection of hair caused by <i>Trichosporon</i> 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 <i>T. ovoides</i>, 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 <i>Trichosporon</i> contains 6 species of clinical significance viz., <i>T. asahii, T. asteroides, T. cutaneum, T. inkin, T. mucoides</i>, and <i>T. ovoides</i>, 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.

Familial White Piedra Caused by <i>Trichosporon inkin</i>

“…The differential diagnosis of white piedra includes black piedra, trichobacteriosis, pediculosis capitis and hair casts [2].…”

Piedra blanca: micosis superficial en un paciente pediátrico

“…1,2 Se ha designado enfermedad de Beigel, tinea nudosa, tricomicosis nodular, tricosporosis nudosa y piedra alba. 3 Es una infección rara, asintomática y crónica que afecta el tallo pilar externamente, sin invadirlo; aparece en forma de concreciones o nódulos adherentes, blandos y blanquecinos, especialmente en la cabeza y en menor frecuencia en la barba, bigote, pestañas, axilas y pubis. 4,5 En 1865 Beigel reportó el primer caso de piedra blanca en Alemania, a través de observaciones en pelucas naturales.…”

Review Article White Piedra: Review of 131 cases

“…The asymptomatic superficial mycosis caused by yeasts of the genus Trichosporon , is called White Piedra (WP) 1 . Derived from the Greek, Trichos (hair) and sporon (spores), refers to the whitish nodules formed by the genus on the stem hair 1,2 . It especially affects the scalp hair and to a lesser extent other hairy areas 2 .…”

“…1 Derived from the Greek, Trichos (hair) and sporon (spores), refers to the whitish nodules formed by the genus on the stem hair. 1,2 It especially affects the scalp hair and to a lesser extent other hairy areas. 2 For a long time, Trichosporon beigelli was considered the etiological microorganism, further analysis by Guého et al 3 documented other six pathogenic species that affected humans.…”