Dermoscopy in tinea capitis: a prospective study on 43 patients Dermatoscopia en tiña de la cabeza: un estudio prospectivo en 43 pacientes

Introduction: For tinea capitis, «comma hairs» and «corkscrew hairs» have been described as dermoscopic patterns by some authors; others have reported small groups of patients diagnosed with tinea capitis with positive dermoscopy; however, there is no data about the sensitivity of dermoscopy in the diagnosis of tinea capitis. We sought to report the results of dermoscopy in a large group of patients with tinea capitis in order to stablish the specificity of dermoscopic examination. Material and methods: Fourty three patients with tinea capitis were evalu- ated clinically and with dermoscopy during a 2 months period in 2011. Direct examination with potassium hydroxide and culture was performed to all patients. Results: Direct examina- tion with potassium hydroxide was positive in all cases and 17 had culture positive for Trichophyton tonsurans, Microsporum canis or Microsporum audouinii. Thirty one patients had positive dermoscopy. «Comma hairs» were found in the seven patients in whom Microsporum canis or Microsporum audouinii were confirmed by culture and in six of the 10 patients in whom Trichophyton tonsurans was isolated.«Corkscrew hairs» were found in three patients with Microsporum canis or Microsporum audouinii and in three patients with Tricophyton tonsurans infection. Comment: «Comma hairs» are not specific for Microsporum or Trichophyton and «corkscrew hairs» are not specific for Trichophyton soudanense, they can be found in other species of Trichophyton and Microsporum. A limitation in our study is the lack of positive cultures in a considerable percentage of potassium hydroxide (KOH) direct examination positive patients. Further studies are needed. RESUMEN