[A case report of pulmonary Mycobacterium kansasii infection found regular medical examination in our medical college of nursing].

A 20-year-old female was checked by chest X-ray film just before starting practical nurse training in the hospital. She was diagnosed as tuberculosis in the initial phase of treatment. In Japan, the number of newly registered tuberculosis has been increasing since 1997, and the stop-tuberculosis campaign is organized by the Ministry of Health and Welfare. The incidence rate of tuberculosis announced officially by the Ministry of Public Welfare was 33.9 per 100,000 in 1997, while that of nontuberculous mycobacteriosis has been increasing year by year, and it was 2.45 in 1997. The one out of 4 nontuberculous mycobacteriosis is caused by M. kansasii. Six colonies of Mycobacterium kansasii were detected by gastric juice culture from this patient. Untreated strains of M. kansasii are susceptible to rifampicin, isoniazid, ethambutol, ethionamide, streptomycin and cycloserine at concentrations readily available in the serum with usual therapeutic doses. Isolates are usually resistant to available serum level of pyrazinamide. The patient was treated with rifampicin, isoniazid and ethambutol for 6 months. Pyrazinamide was stopped at 1 month and 10 days treatment due to liver dysfunction and resistance to the organism. Pulmonary infiltration with cavity disappeared during follow-up examination. Nowadays we must take into account not only tuberculosis but also primary nontuberculous mycobacteriosis at regular medical check of young female.