5 Things to Know About Antimicrobial-Resistant Tinea (Ringworm)

In the past decade, an epidemic of severe antimicrobial-resistant tinea has emerged in certain South Asian and Middle Eastern countries.^[1,2] This is thought to be because of inappropriate use and overuse of topical antifungals and corticosteroids.^[3,4,5] Antimicrobial-resistant tinea infections are frequently caused by the novel dermatophyte species Trichophyton indotineae (formerly known as Trichophyton mentagrophytes ITS genotype VIII).^[6,7]T indotineae infections are characterized by widespread inflamed or dry and scaly pruritic plaques of tinea corporis, cruris, or faciei.^[4,8]

Recently, T indotineae infections have been reported in the United States. Infections have also been reported in Europe and Canada.^[1] Topical antifungals and oral terbinafine are frequently ineffective against T indotineae infections. Other oral antifungal drugs, including fluconazole, griseofulvin, and ketoconazole are also frequently ineffective.^[9] Antimicrobial-resistant tinea caused by the dermatophyte Trichophyton rubrum and azole-resistant dermatophytes are also growing public health concerns.^[10,11]

Here are five things to know about antimicrobial-resistant tinea:

1) Be on the lookout for antimicrobial-resistant tinea.

Healthcare providers should consider T indotineae infection in patients with widespread tinea, particularly when lesions do not improve with first-line topical antifungal agents or oral terbinafine. The lesions of T indotineaeinfection are often widespread annular scaly plaques that are highly pruritic and inflamed. Healthcare providers should ask their patients about travel history.