The Underemphasized Epidemiology of Non- Dermatophytes in Tinea Capitis: A Study from Tertiary Care Hospital, Karachi

Abstract

Background: Tinea capitis (TC) is a fungal infection that victimizes every age group. The fundamental culprits of TC are dermatophytes and the role of non-dermatophytes (NDM) in pathogenesis is overshadowed. Therefore, the current study was designed to evaluate the epidemiology of non-dermatophytes as the etiologic agent of tinea capitis among local population. Methods: It was a cross sectional descriptive study, which was conducted at the Department of Microbiology, Jinnah Post Graduate Medical Centre Karachi Pakistan, from January 2019 to September 2019. A total of 207 patients diagnosed with tinea capitis were enrolled in the study. The scalp scrapings and hair were collected and processed for Potassium Hydroxide (KOH), Lactophenol Cotton Blue (LPCB) and Calcofluor White (CFW) staining. The specimens were cultured on Dermatophyte Test Medium (DTM) and Sabouraud Dextrose Agar (SDA). The species were identified by slide culture, LPCB staining and biochemical tests. The Chi squared test was used for determining the association between variables. The kappa index was utilized for determining the correlation between the efficacies of tests, provided that p-value lesser than 0.05 was considered statistically significant. Results: Among isolated species, 61(29.5%) were dermatophytes and 45(21.7%) were non-dermatophytes. The most common isolated non-dermatophytes were Aspergillus spp. (n=16, 35.5%), followed by Penicillium spp. (n=7, 15.55%). A significant association was observed between the non-inflammatory type of lesions of TC and non-dermatophytes (p-value=0.000). CFW staining was found to be a better tool in detecting fungal components in the specimen compared to KOH mounts (p-value=0.000). Conclusion: The non-dermatophytes carry substantial importance in causing tinea capitis and related superficial scalp mycoses. Keywords: Aspergillus; Dermatophytes; Tinea Capitis; Epidemiology.