Abstract
The pulmonary disease caused by unclassified mycobacteria has been reported in industrial zone where many people worked, but it was not found in rural area, whereas the authors originally found three cases of the disease in NAGANO-ken.
All three patients were male and over forty years old. Two of them have had a chance to inhale a great deal of dust under their circumstances for a long time.
Nonphotochromogen in the culture examination were positive in two of them and scotochromogen in the third case. In all cases roentgenographic findings revealed cavities in their lungs. The susceptibility of unclassified mycobacteria to the antituberculous drugs was much lower than that of human tuberculous bacilli. In the most interesting case human tuberculous bacilli were positive in the culture examination of this sputum. The bacilli were negative in the examination, however, according to the administration of antituberculous drugs for five months. He had the unclassified mycobacteria in his sputum seven months after antituberculous therapy.
We would like to say that in this case the unclassified mycobacteria grew on in the lungs instead of human tuberculous bacilli. That would be, so-called “alternating phenomenon of bacilli”.
