Can Trichoscopy Suggest the Agent in Tinea Capitis?

Abstract

Introduction: Direct mycological examination and culture are the gold standard methods for diagnosing tinea capitis (Tc) despite 4-6 weeks of culture time. Meanwhile, specific trichoscopy patterns may be helpful in its diagnosis.

Methods: This retrospective, cross-sectional, observational study included 31 patients among 110 records from children with presumable clinical and trichoscopic Tc diagnosis, from two dermopediatrics centers, within 10 years. After trichoscopy, skin scraping from the patients was taken for direct mycological examination with 10% KOH and cultures in Sabouraud and Mycosel media; patients with positive cultures for M. canis and T. tonsurans were selected. The association between the trichoscopic and etiological findings of Tc was statistically evaluated using Fisher's exact test.

Results: Some trichoscopy findings, such as perifollicular desquamation and broken hair, were nonspecific to determine the Tc agent. The presence of Morse code (barcode-like) whitish sheath was more common in M. canis infection, even in the small number of patients of our sample. In contrast, comma hairs and black dots were more common in T. tonsurans infection.

Conclusion: The trichoscopy findings suggest the pathophysiology of tinea infection according to the type of parasitism: ectothrix or endothrix and can be a useful tool where there are limited facilities.