Emergence of Difficult-to-Treat Tinea Corporis Caused by Trichophyton mentagrophytes Complex Isolates, Paris, France

Abstract

We describe 7 cases of extensive tinea corporis since 2018 in a hospital in Paris, France, after failure to cure with terbinafine. Molecular analysis indicated Trichophyton mentagrophytes internal transcribed spacer type VIII ( T. indotineae ). This strain, which has mutations in the squalene epoxidase gene, is spreading on the Indian subcontinent.

Trichophyton mentagrophytes ITS genotype VIII and Trichophyton indotineae: A terminological maze, or is it?

“…5,6 The logical term, Trichophyton mentagrophytes ITS genotype VIII, found its place in mycology literature. [7][8][9][10][11] Amid this, a group from Japan described terbinafine resistance in two strains from an Indian and a Nepali patient, based on multigene phylogeny using high mobility group (HMG) and α box genes in addition to the Internal Transcribed Spacer genes used by Nenoff. They introduced these strains, molecularly identical to Trichophyton mentagrophytes ITS genotype VIII, as a new species by the name Trichophyton indotineae.…”

“…9 The highest numbers are found in Germany with stray reports from France, Belgium and Switzerland. 8,9,[26][27][28] Its presence has been noted in China too. 29 Indian dermatologists in certain parts of the country see many Indian patients coming from Africa and a majority of them give a history of steroid misuse as steroid-antifungal fixed dose combination creams are freely available over the counter there, as is seen in the Indian subcontinent and in the Middle East Asian countries.…”

Trichophyton indotineae—An Emerging Pathogen Causing Recalcitrant Dermatophytoses in India and Worldwide—A Multidimensional Perspective

“…Within Europe, the majority of non-Indian patients with tinea caused by this species have been reported in Germany ( Figure 2 ) [ 7 ]. Furthermore, dermatophytoses due to T. indotineae has been described in France [ 8 , 9 ], Belgium [ 10 ], Switzerland [ 11 ], Greece [ 12 ], Denmark [ 13 ], China, Australia, Canada [ 14 , 15 ], and recently, in Vietnam [ 16 ].…”

Terbinafine Resistance in Dermatophytes: A French Multicenter Prospective Study

“…Afterwards, population flows, associated with increased travel and migration, have allowed the spread of TerR isolates to different European countries [ 20 , 21 , 22 ] altering the local epidemiology of dermatophytes [ 23 ]. We and others have recently reported a series of TerR dermatophytoses due to T. indotineae in France [ 24 , 25 ] but the current relative frequency of TerR and of T. indotineae isolates remains unknown. Therefore, we conducted a prospective multicenter study to (i) determine the relative frequency in the Paris area, in France, of TerR clinical isolates implicated in onychomycosis, tinea pedis, cruris and corporis, (ii) gain insights into the current epidemiology of T. interdigitale , T. mentagrophytes , and T. indotineae and (iii) determine their susceptibility to four antifungal agents (terbinafine, itraconazole, amorolfine and voriconazole).…”