Abstract
We encountered a 10-month-old girl who developed refractory black-dot ringworm of the head caused by Trichophyton tonsurans. The source of infection was her mother, who had played judo until 3 years before marriage. The present case raised the following issues: the oral administration of antimicrobial agents to infants aged 10 months was limited; we hesitated to administer oral therapy, considering the risk of a side effect-related lawsuit; her mother had been an asymptomatic carrier over 3 years; her father was also infected, and all 3 family members developed this disorder; and the reliability of fungus identification by the clinical laboratory was low. Trichophyton tonsurans infection spreads not only among judo practitioners but also to their families via vertical infection. The important point in Trichophyton tonsurans or Microsporum canis infection control is to pursue the source of infection and prevent its transfer to a new population. An education program to improve dermatologists'; ability to identify fungus must be developed as soon as possible. It is important to promote the role of dermatologists in society via preventive medicine-based activities. In patients with alopecia of the head, black-dot ringworm should always be considered. On consultations, it must be recognized that judo practitioners consist of both males and females. (Online only)
