On the Virulence of Atypical Acid- Fast Bacilli for Mice and Guinea pig

The existance of acid-fast bacilli producing pulmonary disese in humans, but differing from Mycobacterium tuberculosis in cultural characteristics and in failure to produce progressive disease in the guinea pig, has been reported sporadically for many years in other countries than Korea, but recently this has come to be reported with increasing frequency and interest. In Korea, the existence and biological characteristics of this so called atypical acid-fast bacilli has been first reported by Dr. K.s. Kim at the 12th Annual Meeting of Tuberculosis Association. Here. this writer intended to study the virulence of atypical acid-fast bacilli for guinea pig and mice for further knowledge successively.1) The virulence for mice and guinea pig with three atypical acid-fast bacilli strains was demonstrated. Photochromogens, nonphotochrmogens and scotochromogens were the used strains and among them the photochromogens were proved to be strongly virulent for mice.2) Tuberculin test was done to the whole used animals and the majority of mice showed positive reaction to O.T.(1:100), while guinea pig remained negative.3) Repeated isolation from lesions was possible and microscopic section of the lesion in the lyver, spleen and lung showed so-called the young epithelioid tubercle which was histopathologically indistinguishable from tuberculosis.