[Questionnaire investigation of incidence of Trichophyton tonsurans infection in dermatology clinics in the Kanto area].

We conducted a questionnaire investigation to learn the incidence of T. tonsurans infection. Subjects of this investigation were 1,060 dermatologists in 1,060 dermatology clinics in the Kanto area to whom questionnaires were mailed. We asked each dermatologist whether he/she had experienced T. tonsurans infection cases (including suspected cases) and if so, we further asked; a. time of onset, b. number of cases, c. sexuality of the patient, d. club that the subject had joined (judo club, wrestling club or other), e. age of the subject, and f. number of cases suspected of having familial infection, the response rate was 47.5% (504 of the 1060 doctors), and 25.8% (130 of the 504) had handled T. tonsurans infection cases. The total number of patients was 707 (657 males and 50 females), with 400 (56.6%) of those in the 18 high-ranking clinics. The number of cases had increased rapidly from around 2002; 72.9% of the patients were students in high schools and universities and in 8 cases familial infection was suspected. 96.5% of the patients were in a judo or wrestling club. Our investigation revealed that this infectious disease had spread more than we had expected. It is important to develop more reliable infection control measures and to determine the actual conditions of this infection using mycological examinations.