Background: Dermatophytosis is a prevalent superficial infection caused by filamentous fungi, primarily affecting the skin and/or its appendages. In recent years, there has been a notable increase in mycotic strains resistant to standard antifungal therapies, including Trichophyton indotineae, a dermatophyte of the Trichophyton mentagrophytes complex. This review aims to provide a comprehensive overview of the treatment options for T. indotineae, elucidating their effectiveness in managing this challenging mycotic infection. Methods: For this review, a search was conducted in the PubMed, Scopus, Web of Science, Embase, and Google Scholar databases, encompassing all published data until March 2024. English-language articles detailing therapy outcomes for patients confirmed to be affected by T. indotineae, identified through molecular analysis, were included. Results: Itraconazole was shown to be a good therapeutic choice, particularly when administered at a dosage of 200 mg/day for 1–12 weeks. Voriconazole was also demonstrated to be effective, while terbinafine exhibited a reduced response rate. Griseofulvin and fluconazole, on the other hand, were found to be ineffective. Although topical treatments were mostly ineffective when used alone, they showed promising results when used in combination with systemic therapy. Mutational status was associated with different profiles of treatment response, suggesting the need for a more tailored approach. Conclusions: When managing T. indotineae infections, it is necessary to optimize therapy to mitigate resistances and relapse. Combining in vitro antifungal susceptibility testing with mutational analysis could be a promising strategy in refining treatment selection.

In recent years, there has been a concerning increase in a challenging‐to‐treat dermatophyte lineage of the Trichophyton mentagrophytes complex, known as Trichophyton indotineae. We report the first case of resistant T. indotineae bearing a double mutation in the squalene epoxidase gene (SQLE), isolated in Italy from a 26 ‐year‐old Nepali woman affected by a persistent tinea corporis. Topical terbinafine yielded minimal to no improvement while itraconazole provided partial relief but failed to eradicate the infection. Molecular identification through Sanger sequencing of the internal transcribed spacer region confirmed T. indotineae and sequencing of the SQLE gene revealed the presence of a double mutation (Phe397Leu/Ala448Thr) associated with antifungal resistance. Broth microdilution susceptibility testing demonstrated resistance to fluconazole, but susceptibility to itraconazole. Ultimately complete cure was achieved with prolonged high‐dose itraconazole therapy.

Melanoma is known to have a high prevalence of somatic mutations, leading to a wide range of clinical and histological variability. This genetic plasticity can result in the partial or total loss of typical diagnostic clinical and immunohistochemical features of melanoma. Undifferentiated melanoma (UM) and dedifferentiated melanoma (DM) pose a significant diagnostic challenge due to their histological atypia and the absence of conventional melanocytic markers, often making them indistinguishable from pleomorphic dermal sarcoma (PDS). Accurate differentiation, however, is critical as UM and DM, unlike PDS, display a higher metastatic potential. Molecular analysis plays a crucial role in accurate diagnosis, particularly through the detection of mutations such as BRAF and NRAS, which are rarely found in true sarcomas. We present 2 cases of primary cutaneous UM initially misdiagnosed as PDS and later reclassified based on molecular findings. A comprehensive review of the literature was performed of reported cases of primary cutaneous undifferentiated and DM. Timely diagnosis is vital to allow access to effective targeted therapies, such as immune checkpoint inhibitors and BRAF/MEK inhibitors, which have shown promising responses, suggesting that undifferentiated and DM respond similarly to conventional melanoma despite their atypical presentation.