Evaluating the Role of Antifungal Resistance in Treatment Failure of Dermatophytosis: A Systematic Review
Antifungal Resistance and Treatment Failure in Dermatophytosis
Keywords:
Antifungal Resistance, Dermatophytosis, SQLE Gene Mutations, Trichophyton Indotineae, Terbinafine ResistanceAbstract
Background: The antifungal resistance during the treatment of dermatophytosis is becoming a global concern. Recently, the new dermatophyte strains, most significantly, Trichophyton indotineae (formerly T. mentagrophytes genotype VIII) has shown increased resistance against the antifungal medications in South Asia and other close regions. Henceforth, this review aims to systematically analyse current evidence regarding antifungal resistance in dermatophytes and evaluate its impact on treatment outcomes in patients with superficial fungal infections of skin.
Methodology: A systematic review was performed by searching PubMed/MEDLINE and Scopus using keywords ‘dermatophytosis’, ‘antifungal-resistant dermatophytes’, ‘failed treatments’ and ‘recurrence’. During the search, 3,205 records were screened, and nine studies were included. Researchers extracted data on study designs, sample, fungal infections, resistance mechanisms, treatments and outcomes. The risk of bias of the included studies was assessed using Cochrane RoB2 and Newcastle–Ottawa Scales (NOS), and the findings were considered during the interpretation of the results.
Results: Terbinafine resistance was highest in T. indotineae, with 70% of isolates showing MICs of ≥0.5 mg/L. In North India, 60% of dermatophyte isolates were resistant to terbinafine and 85.6% to fluconazole, whereas itraconazole, ketoconazole and griseofulvin remained active. Higher terbinafine MICs were linked to slower cure and the need to switch to itraconazole, and itraconazole cured 92.5% of patients with terbinafine-resistant T. indotineae when serum levels exceeded 0.2 µg/mL. Where resistance was not tested, a two-week terbinafine course gave sustained cure in only 43% of patients. Most studies were observational, and few related MICs directly to clinical response.
Conclusion: Nevertheless, the preponderance of data suggests that antifungal resistance is indeed hindering effective therapy of dermatophytosis, especially where resistant T. indotineae dominates. Moreover, it is recommended that physicians should anticipate resistance in intractable cases, perform appropriate susceptibility testing, and consider strong antifungal options including itraconazole or other alternatives.
DOI: https://doi.org/10.59564/amrj/04.04/011
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