Tuberculosis. 



309 



situation and there caused the disease. Generally the whole 

 path traversed hy the l)acilli is mapped out l)y foci of the 

 disease, first the primary local focus and after it the neighl^oring 

 regional infection, then the secondary tuberculosis of the lymph 

 glands which receive the lymph from the afifected part. From the 

 latter along the lymphatics or, as above mentioned, by the chylous 

 route, the germs find their way into the blood or may directly pene- 

 trate through the walls of the blood vessels in the course of the tu- 

 berculous proliferation ; and then, depending upon whether many or 

 only isolated bacilli are carried to the various organs, there is pro- 



Uteriiit^ tuliorcuUisis, from cow. 



duced a iiictastafic, hccmafogciifliis, embolic, multiple or dissemi- 

 nated miliary tuberculosis of the lungs, brain, liver, kidneys, etc. 

 Muscle (meat) shows the greatest degree of resistance, usually only 

 the intermuscular lymph nodes being affected. This general inva- 

 sion of the tuberculous virus with its resulting tuberculous foci is 

 spoken of as general tuberculosis. The metastatic miliary nodules 

 of course increase in size, and by confluence and advancing casea- 

 tion cause progressive extension of the tuberculous destructive 

 changes. Finally, too, contact infection along mucous membranes 

 occurs from the convection of the germs over the surface with its 

 fluid secretion, as infection of the larynx from the lungs, of the 

 vulva from the uterus, etc. 



