<i>Trichophyton mentagrophytes</i> Genotype <scp>VII</scp> : Sexually Transmitted Infection Beyond <scp>MSM</scp>

Trichophyton mentagrophytes is a zoophilic dermatophyte causing superficial fungal infection. Among its variants, Trichophyton mentagrophytes genotype VII (TMVII) has been recently recognised as a distinct genotype and has been increasingly linked to sexually transmitted infections [1]. While the earliest reports of TMVII infections in Europe mainly involved patients who had had contact with commercial sex workers in Southeast Asia [2], more recent evidence indicates that TMVII is circulating across the continent, particularly among men who have sex with men (MSM) [3-6]. In a previous study, we documented the first confirmed cases of sexually transmitted TMVII infection in Italy, all occurring in MSM patients and manifesting as tinea barbae. Here, we report a more recent case series collected at our Dermatology Unit between October 2024 and December 2025, which shows a more heterogeneous patient population. Epidemiological and clinical data are summarised in Table 1. The diagnosis of T. mentagrophytes infection was established through mycological cultures, and genotyping of the ITS1–2 region confirmed the presence of TMVII. Patients were treated with oral terbinafine 250 mg daily or itraconazole 200 mg daily for 4 weeks in combination with topical antifungal therapy. Treatment was effective in all patients, with no evidence of recurrence or antifungal resistance. Following the first reports of autochthonous sexually transmitted TMVII infections in France [3, 4] and Italy [5], increasing evidence has documented the spread of this infection across several European countries and worldwide [2]. While early reports described cohorts composed exclusively of men who have sex with men (MSM) [3-6], subsequent studies have identified TMVII infections in heterosexual individuals of both sexes [1, 7, 8]. In our cohort, more than 60% of patients (8/13) reported heterosexual orientation and about 23% (3/13) were women. TMVII is not restricted to a specific sexual related anatomical site (e.g., beard or pubo-genital area) but may involve multiple body regions, such as arms and legs [1]. Many of our patients showed atypical presentations of tinea corporis, including painful erythematous plaques, pustules and nodules, occasionally progressing to granulomatous lesions or erosive lesions with eschar formation [2]. Although TMVII is transmitted through anthropophilic contact, its close genetic relationship with zoophilic genotypes within the T. mentagrophytes complex may account for the marked inflammatory response observed [7]. Interestingly, more inflammatory lesions predominantly involved hair-bearing areas, such as the beard and pubic region, whereas lesions on the trunk or shaved perigenital skin more often displayed the classical ringworm morphology. Two patients in our cohort were stable partners presenting with matching lesions (tinea cruris in the female partner and tinea barbae in the male partner) following reported oral–genital contact, further supporting sexual transmission as a likely route of infection [9]. Four of 13 patients presented with concomitant sexually transmitted infections (STIs), underscoring the importance of routine screening for other STIs in patients with fungal infections suspected to be sexually transmitted [1]. One patient concurrently showed cutaneous manifestations of both TMVII infection and mpox (Figure 1d). Mixed cutaneous lesions caused by different conditions should therefore be considered, as they may complicate clinical assessment [2]. No obvious STI risk factors were identified in 6 of 13 cases: the hypotheses considered include indirect environmental contamination, direct human-to-human transmission through non-sexual contact, and unreported heterosexual or same-sex sexual relationships. The diagnosis of sexually transmitted TMVII infection relies on a high index of clinical suspicion and molecular confirmation through PCR amplification of the ITS1–2 region. However, this test is not universally available and is not routinely performed, suggesting that the number of confirmed cases may underestimate the true burden of this infection [10]. Supporting this hypothesis, in a retrospective study Maci et al. reported 107 cases of sexually transmitted dermatophytosis (STD) diagnosed at their dermatology clinic in Milan between 2010 and 2023, with half of the cases occurring in 2022–2023 alone [11]. In conclusion, TMVII infection is increasingly recognised as an emerging sexually transmitted infection (STI) with a growing global distribution. Unlike other emerging strains causing tinea genitalis, such as T. Indotinae, no specific antifungal resistance has been reported for TMVII [9]. Dermatologists should maintain clinical awareness, as it may affect the broader sexually active population. The authors have nothing to report. Open access publishing facilitated by Universita degli Studi di Milano, as part of the Wiley - CRUI-CARE agreement. The authors have nothing to report. The authors declare no conflicts of interest. The data that support the findings of this study are available from the corresponding author upon reasonable request.