164 THE RELATIONS OF MICRO-ORGANISMS TO DISEASE. 



with but very slight lesions of the intestinal mucosa, bacteria in large 

 numbers may gain access through this to the liver, where they may be 

 destroyed or under certain conditions eliminated, either through the bile 

 or into the body at large. ' 



Action of Bacteria and their Products in the Body. 



When bacteria do enter and grow in the body, the cells and tissues 

 near them may show very marked alterations, due to their influence. 

 The cells may be swollen, or their nuclei may disappear, and the proto- 

 plasm may be converted into a mass of shining or coarsely granular 

 particles, or may completely disintegrate. The intercellular substance 

 near the bacteria may also soften and disintegrate. In a word, the 

 tissue in their immediate vicinity is often found in a condition of necro- 

 sis of one kind or another. The walls of blood-vessels near which they 

 lie may be damaged and the blood which these carry may form thrombi. 

 The bacteria may themselves enter the vessels and proliferate in the 

 blood ; they may be swept away as emboli to remote parts of the body 

 (Fig. 41, page 113), and establish new foci of bacterial proliferation and 

 tissue necrosis septicaemia. 



Some bacteria, instead of inducing a simple necrosis, incite at the 

 same time, as we have already seen, a more or less intense inflammation 

 (Fig. 42, page 114). This inflammation may be of a simple productive 

 form, similar in its effects to that incited by the presence of any irri- 

 tating foreign body ; or it may be active, progressive, and exudative in 

 character; or the bacteria may determine, in some way as yet unknown 

 to us, very peculiar and characteristic inflammatory changes, which re- 

 sult in the formation of new tissues of various kinds (see Tuberculosis). 

 Some forms of bacteria find in the blood, others in the tissue spaces and 

 lymph-vessels, the conditions most favorable for their proliferation. 



But the presence of micro-organisms themselves is not indispen- 

 sable for the incitement of either local or general pathological processes. 

 These may be induced by various chemical products eliminated or stored 

 up in their protoplasm by the metabolism of the germs. These delete- 

 rious bacterial products may, as we have already seen, be those alkaloidal 

 substances called poisonous ptomains or toxins, or they may be albumi- 

 noid substances toxdfbumins or toxalbumoses* Stored up in the proto- 

 plasm of the germs themselves, this poisonous material has been called 

 bacteria -protein. 



Some of the poisons act locally at or near the seat of their manufac- 

 ture by the growing germs. Others gain access to the body at large and 

 are widely distributed, inducing w r hat may be called the phenomena of 

 septic intoxication toxasmia. 



1 Adami, on "Latent Infection and Subinfection," etc., Journ. of the Amer. Med. 

 Association, December 16th and 23rd, 18U9. 



9 Much of the literature on this subject has been brought together by Vaughan and 

 Novy, "Cellular Toxins." The general chemical relationship of bacterial products to 

 other organic compounds is set forth in Halliburton' s "Text-Book of Chemical Physi- 

 ology and Pathology " ; see also Oppenheimer on " Bacterial Poisons " in Kolle and Was- 

 sermann's "Handbuch der Mikroorganismen," Bd. i., p. 844. 



