Adult black dot tinea capitis caused by Trichophyton tonsurans complicated with herpes zoster

A 53-year-old Chinese female who presented with a 3month history of scalp erythema, scaling, and pruritus visited our department. Physical examination revealed erythema, escharosis, and multiple interspersed alopecia patches across the scalp [Fig. 1A]. The dermatoscopy showed scales and corkscrew hairs broken at a distance of 0.5 to 2.0 mm from the scalp with a black spot appearance [Fig. 1B]. Direct potassium hydroxide examination revealed septate hyphae in the scale samples and endothrix spores [Fig. 1C]. Hair stumps were plated in Sabouraud dextrose agar at 25°C for fungal culturing. On the 7th day, the colonies were round with flat edges, white powder on the surface, and brownish red on the back. We adhered cellophane to the surface of the colonies and observed under the microscope; there were abundant branched mycelia, with numerous cord shapes and a small number of pyriform microconidia, with some expanded into spheres. Macroconidia were typically visible with transverse septa and thin, curved walls [Fig. 1D]. After culturing for 2 weeks, the colony center was slightly convex, and the surface was covered with white villous mycelia with radial furrows [Fig. 1E]. The back was flat with a reddish-brown color [Fig. 1F]. Thick-walled spores were common under the microscope; articular spores were occasionally seen, and racquet hyphae were visible [Fig. 1G]. Microculture was further performed in potato dextrose agar medium at 25°C for 7 days; lateral microconidia and mycelia were observed under the microscope, and thick-walled spores were abundant [Fig. 1H]. The fungal strain was identified by DNA sequence analysis using internal transcribed spacer (ITS)-1 and ITS-4 primers, and the results showed a 98.1% consistency with T. tonsurans (GenBank accession