The types of tubercle bacilli in lupus and scrofulodermia

Abstract

1. Cultures of tubercle bacilli were obtained from 204 cases of lupus.2. According to their cultural characters the strains could be divided into two main groups, one containing 102 strains with the characters of human tubercle bacilli and the other containing 102 strains with the characters of bovine tubercle bacilli.3. Virulence tests were carried out on a large number of animals, and in one instance over 100 animals were used for testing strains from a particular case.4. Of the 102 culturally human strains 41 were highly virulent for the guineapig, and for the monkey when this was tested, producing progressive and rapidly fatal tuberculosis. The remaining 61 strains (59.8%) showed varying degrees of attenuation.5. Of the 102 culturally bovine strains 34 were highly virulent for all the animals tested, producing in them severe and rapidly fatal general tuberculosis identical with that set up by standard bovine bacilli. The remaining 68 (66.7%) were of lower virulence for the rabbit, and for the calf and goat when these animals were tested, than standard bovine strains, but they all produced in one, two, or three of these species more extensive tuberculosis than human bacilli. For the guineapig, and for the monkey when tested, these strains fell below the virulence of standard bovine strains, except for a few whose virulence was only slightly lowered for the rabbit.