Studies on the lung disease due to non-tuberculous mycobacteria in Japan (report of the year 1982 of the Mycobacteriosis Research Group of the Japanese National Chest Hospitals)

In the period of one year from the 1st January 1982 to the 31st December 1982, 3,257 patients with mycobacterial lung disease were admitted to tuberculosis departments of participating hospitals. Of these, 111 were those with non-tuberculous lung mycobacteriosis. The ratio of patients with non-tuberculous lung mycobacteriosis against the total number of patients including tuberculosis was 3.4%. From this ratio and the prevalence rate of active lung tuberculosis in 1982, 48.5 per 10 super(5) population, the prevalence rate of non-tuberculous lung mycobacteriosis was estimated as 1.65 per 10 super(5) population. The prevalence rate of active lung tuberculosis is continuously decreasing from the year 1971 to the year 1982. In contrast, the prevalence rate of non-tuberculous lung mycobacteriosis is almost constant, 1 to 2 per 10 super(5) population during the same period. The ratio of non-tuberculous lung mycobacteriosis in the total number of hospitalized patients with lung disease is contiuously increasing.