Extra-Scalp Black Dot Ringworm Caused by Trichophyton tonsurans Among Contact Sports Players

• Published in: Mycopathologia (1975) Vol. 173; no. 4; pp. 241 - 244
• Main Authors: Mochizuki, Takashi, Kawasaki, Masako, Anzawa, Kazushi, Kojima, Kiyoto, Hatta, Junko, Tababe, Hiroshi, Higaki, Shuichi, Fujita, Shigeru
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.04.2012; Springer; Springer Nature B.V
• Subjects: Adolescent; Adult; Antifungal Agents - therapeutic use; Biomedical and Life Sciences; Dartrose; Erythema; Eukaryotic Microbiology; Fungal infections; Fungi; Hair; Health aspects; Humans; Life Sciences; Male; Martial Arts; Medical Microbiology; Microbial Ecology; Microbiology; Patients; Plant Sciences; Polymorphism; Ribosomal DNA; Ringworm; Scalp; Skin; Sports; Terbinafine; Tinea capitis; Tinea Capitis - drug therapy; Tinea Capitis - microbiology; Tinea corporis; Trichophyton - isolation & purification; Trichophyton tonsurans; Venus; Japan; Hairy skin; Black dot ringworm; Tinea corporis
• ISSN: 0301-486X; 1573-0832
• DOI: 10.1007/s11046-011-9501-z

We describe here two patients with tinea corporis exhibiting black dot ringworm (BDR). A cluster of black dots was observed on the extensor surfaces of the extremities of two rather hairy male patients, a 15-year-old judo practitioner and a 26-year-old combined martial arts fighter, during treatment of tinea corporis with topical antimycotics. Direct KOH examination showed that the black dots were composed of degenerated hair with numerous arthroconidia and were indistinguishable from BDR of tinea capitis. Trichophyton tonsurans was isolated from the dots of both patients. Although they were diagnosed with tinea corporis, they required 2–3 months of treatment with oral terbinafine. Dermatologists should be aware that BDR can appear on areas of the skin other than the scalp.