<i>Microsporum audouinii</i>: Emergence of an etiological agent of tinea capitis in Rio de Janeiro, Brazil (2012–2019)

The etiology of tinea capitis changes over time, mainly due to trends in migration. We report 19 cases of tinea capitis caused by Microsporum audouinii, an uncommon agent in South America, all of them confirmed by molecular methods. All patients were male. The average age was 6.1 years. Fifteen patients were residents of Rio de Janeiro city and four were from neighboring cities. Among the patients submitted to follow-up, griseofulvin was prescribed for eight of them. Due to medication shortages, terbinafine was prescribed for five patients, needing to be switched in three cases, with a bigger total average time until clinical improvement. The study reaffirms the emergence of a new etiological agent in Rio de Janeiro, Brazil.