[Results of initial bacteriology of pulmonary tuberculosis among male NTT employees in the Tokyo area--annual transition and influence of fiberoptic bronchoscopy].

A study was made on the annual changes in the positive rate for acid-fast bacilli (AFB) at the initial bacteriological examination of newly detected pulmonary tuberculosis among male NTT (Nippon Telegraph and Telephone Corporation) employees in the Tokyo area during a period of 32 years from 1960 through 1991. The influence on the changes of recent introduction of fiberoptic bronchoscopy for obtaining the specimen was also analyzed, and the following results were obtained. 1. Results obtained by the conventional bacteriological method using expectorated sputum or aspirated gastric juice as the specimens. (1) The annual incidence of bacteriologically positive (smear and/or culture positive) cases constantly decreased and reached the lowest in 1981, then ceased to decline and remained at the level of 1981. (2) The annual ratio of AFB positive by smear and the ratio of smear and/or culture positive cases to the newly detected cases of pulmonary tuberculosis were constant during the entire observation period. (3) The ratio of AFB positive by smear to the newly detected cases annually increased but did not increase when the observation period was limited to within 1976 to 1991. 2. Results obtained by fiberoptic bronchoscopy in combination with conventional bacteriological methods. (1) Both the annual incidence of smear and/or culture positive cases and the ratio of these cases to the newly detected cases of pulmonary tuberculosis showed a tendency to increase in both the 80's and 90's.(ABSTRACT TRUNCATED AT 250 WORDS)