Etiological prevalence and antifungal sensitivity patterns of dermatophytosis in India – A multicentric study

Abstract

Background: The prevalence of dermatophytes varies with season, geographical area, socio-economic factors and effective management strategies. Aims: The aim of the study was to assess the prevalence of pathogenic dermatophytes, clinical types of dermatophyte fungal infection, and in vitro antifungal drug susceptibility testing against dermatophytes. Methods: Three hundred and ninety five patients with dermatophytosis were enrolled from five cities (Mumbai, Delhi, Lucknow, Kolkata and Hyderabad) across India. All patients were subjected to clinical examination and investigations, including potassium hydroxide microscopy, fungal culture and antifungal drug susceptibility testing. Results: Trichophyton rubrum was the most common species identified (68.4%), followed by T. mentagrophytes (29.3%). Within species, T. mentagrophytes was prevalent in humid environmental conditions (Mumbai and Kolkata), whereas T. rubrum was prevalent in noncoastal areas (Delhi, Lucknow and Hyderabad). Tinea corporis (71.4%) and tinea cruris (62.0%) were the common clinical types observed. antifungal drug susceptibility testing data indicated that minimum inhibitory concentration required to inhibit the growth of 90% of organisms (MIC-90) was lowest for griseofulvin (0.25–3.0 μg/mL). Among oral antifungals, the mean MIC of itraconazole was within the range (0.84 [0.252] μg/ mL), whereas high mean MIC values were reported for terbinafine (0.05 [0.043] μg/mL). Among topical agents, lowest mean MIC values were reported for luliconazole (0.29 [0.286] μg/mL), eberconazole (0.32 [0.251]) μg/mL and amorolfine (0.60 [0.306]) μg/mL. Limitations: Lack of correlation between in vitro antifungal susceptibility and clinical outcome and absence of defined MIC breakpoints. Conclusion: T. rubrum was the most common, followed by T. mentagrophytes as an emerging/codominant fungal isolate in India. Tinea corporis was the most common clinical type of dermatophytosis. Mean MIC of terbinafine was above the reference range, while it was within the range for itraconazole; griseofulvin had the lowest mean MIC. Luliconazole presented the lowest mean MIC values across cities.

A clinical prevalence of dermatophytic mycoses with an assessment of its clinical manifestations in a tertiary care hospital at Salem, South India

“…This study didn't come across any cases of tinea capitis which involves the scalp region which is more commonly seen in children and also tinea manuum which involves one or both hands. The previous studies have also concluded that other than tinea incognita, tinea corporis is the most prevalent type compared to the other clinical types of dermatophytoses 5,32–34 …”

“…The previous studies have also concluded that other than tinea incognita, tinea corporis is the most prevalent type compared to the other clinical types of dermatophytoses. 5,[32][33][34] In the analysis of KOH mount and culture findings, out of all the sample specimens, there were 89% KOH mount, and 81% were culture isolates positive for dermatophytosis. In this present study, T. rubrum (61%) was the most predominant dermatophyte isolated also described by this studies.…”

Evaluation of the benefit of the addition of 1% topical luliconazole versus topical bland emollient to the systemic itraconazole therapy for the management of disseminated dermatophytosis: A randomised control trial

“…Moreover, one of these studies shows no effect on relapse rate between 100 mg, 200 mg or 400 mg per day regime of ITZ. The majority of recent studies suggest MIC for ITZ against the trichophyton group of fungi remains low well within the upper normal limit of wild‐type strains 19,20 . Study by Khurana et al 21 .…”

“…The majority of recent studies suggest MIC for ITZ against the trichophyton group of fungi remains low well within the upper normal limit of wild-type strains. 19,20 Study by Khurana et al 21 demonstrated that plasma levels of ITZ above 0.2 μg/mL are consistently associated with therapeutic success which can be easily achieved with 100 mg/day doses of the drug. Dose of ITZ (200 mg/ day), recommended by various guidelines and routinely prescribed by dermatologist in India is well above this threshold.…”

IADVL SIG Recalcitrant Dermatophytosis Position Statement on Super Bioavailable Itraconazole

“…Available studies from India and abroad suggest that the prevalent species of the present epidemic of dermatophytosis in India exhibits low MIC for ITZ as yet. [ 15 16 ] There are no widespread reports of increase in MIC or any genetic mutation linked to reduce the susceptibility of Trichophyton genera of dermatophytes to ITZ.…”