Determination of dermatophytes isolated from tinea capitis using conventional and ITS-based sequencing methods in...

Tinea capitis is a dermatophyte infection of the scalp and hair that affects a large number of people worldwide. The disease commonly affects children and manifests with varying degrees of hair loss, scalp inflammation, and psychosocial impact. In Nigeria, the burden of tinea capitis is worrisome affecting over 15,000,000 school-age children. Molecular techniques complement the conventional mycological examinations in laboratory diagnosis of tinea capitis. In this study, we identified dermatophytes species causing tinea capitis in Kano, Nigeria, using ITS-based nucleotide sequencing technique in addition to conventional mycological examination.

We collected 112 samples from the scalp of children with clinically diagnosed tinea capitis at the dermatology clinic of Murtala Muhammad Specialist Hospital, Kano, between April and September 2019. The samples were processed and subjected to direct microscopy and mycological culture to isolate dermatophytes species that were identified morphologically and using ITS sequencing.

Out of the 112 patients investigated, the majority (59.8%) were between the ages 6 and 9 years with a mean age of 7.3 ± 1.9 years. Males (79.5%) were predominantly affected. Black dot (46.4%) was the most common clinical type of tinea capitis followed by gray patch (39.3%) and kerion (1.8%). Favus was not observed. Microsporum audouinii (45.7%) was the predominant etiologic agent followed by Trichophyton soudanense (28.6%), T. violaceum (22.9%), and T. tonsurans (2.9%).

The prominence of anthropophilic dermatophytes as the main causes of tinea capitis in our localities suggests that public health interventions to promote health education and good hygiene practices would minimize the transmission rate of tinea capitis among children in the study area.