196 BACILLUS TUBERCULOSIS. 



however, that children born of tubercular parents, or of a 

 tubercular father or mother, are predisposed to tuberculosis 

 because of the lack of sufficient vitality to resist that or any 

 other infection. 



Baumgarten believes that the disease is inherited directly, 

 but that the great vitality of the tissues of the developing 

 child inhibits the growth of the tubercle bacillus, so that the 

 germ remains latent in the bone-marrow, lymph-glands, and 

 other parts of the body until such time when, either through 

 traumatism or disease, the natural barriers to infection are 

 removed. He and others have found living but inactive 

 tubercle bacilli in the organs of babies born of tubercular 

 mothers. Gsertner is of the opinion that the bacillus is not 

 transmitted to the foetus by the mother, but that during par- 

 turition the bacillus may, in consequence of tears in the pla- 

 centa, be conveyed to the child. This is the most plausible 

 explanation of those infrequent cases of primary tuberculosis 

 of the skin, bones, joints, liver and other organs, which occur 

 in young children who' present no other evidence of tubercu- 

 losis. 



Mixed infection : The occurrence of mixed infection in 

 tuberculosis is quite common, and materially lessens the 

 chances of recovery from the original infection. This is 

 especially true in pulmonary tuberculosis when a septicaemia 

 is added to the tuberculosis. The organisms which are most 

 frequently associated with the tubercle bacillus are the strep- 

 tococcus, staphylococcus, Micrococcus tetragenus, pneumococ- 

 cus, influenza bacillus, and Bacillus pyocyaneus. 



Demonstration of the bacillus : Sputum : The demonstration 

 of the bacillus in the tubercular material or tissue is positive 

 evidence of the existence of the disease. Failure to find the 

 germ in stained specimens is not positive evidence of the non- 

 existence of the disease. It should be borne in mind that 

 frequently, especially in the incipient stages of tuberculosis 

 repeated examinations must be made before it is possible to 

 find the organism. It is always well to make five or six 

 stained specimens, and if the bacillus is not found in these, 

 several more should be prepared, and finally the microscopic 

 finding should be substantiated by the injection of guinea-pigs. 



