Clinical spectrum and mycological delineation of Tinea incognito using matrix assisted laser desorption / ionisation - Time of flight (MALDI-TOF)Technology

Dermatophytosis is a superficial fungal infection of keratinized tissue caused by keratinophilic fungi called dermatophytes. Dermatophytes metabolize dead keratin and evoke an eczematous response. This response leads to a poor supply of keratin to the fungus, thereby limiting the infection. Immunosuppressants such as steroids suppress this protective eczematous response, enhancing fungal growth. Clinically, these lesions have a less raised margin, and are not as scaly as classic dermatophytosis. They tend to be extensive, pruritic, erythematous and pustular, and may mimic other skin diseases.The unregulated sale and erratic , unsupervised use of topical steroids and fixed dose combination creams (FDC) containing steroids are considered prime culprits in the unprecedented epidemic of recalcitrant dermatophytosis on the indian subcontinent as well as in the middle eastern countries.Most FDCs are combinations of two, three, and even four drugs viz. one  antifungal agent like, miconazole, clotrimazole, ketoconazole; a potent corticosteroid, the commonest being clobetasol propionate; and one or two antibacterial agents like neomycin, gentamycin etc. A new diagnostic approach using the matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF) mass spectrometry (MS)-based strategy has facilitated the effective identification of clinical dermatophyte isolates.