PATHOGENIC BACTERIA 153 



Autopsy shows greatly enlarged spleen and myriads of bacilli 

 in the blood and viscera, the lungs not especially affected. If 

 injected into the trachea, a pneumonia occurs. In man they 

 are found in 90 per cent, of croupous pneumonia, and usually 

 only during the existence of the rusty sputum, i. e., the first 

 stage. 



The bacilli have also been found in pleuritis, peritonitis, peri- 

 carditis, meningitis, and endocarditis. They stand in some 

 intimate relation to all infectious inflammations of the body. 

 Their presence in healthy mouth secretion does not speak 

 against this, it requiring some slight injury to allow this ever- 

 present germ to develop into disease. 



Antitoxin of Pneumonia (Klemperer) . The injection 

 of very diluted cultures of the virulent bacilli intravenously 

 has produced an immunity in rabbits and guinea-pigs. The 

 serum of such artificially immune animals when filtered through 

 a Chamberland filter and injected into a rabbit suffering with 

 pneumonia, cured the same; or when injected into a susceptible 

 animal, produced in it immunity very quickly. This principle 

 is ascribed to an antitoxin formed in the tissues by the diluted 

 proteids, and this antitoxin neutralizes the toxicity of the strong 

 virus. The attempt to treat with antitoxins has been aban- 

 doned, the disease ending so rapidly by crisis that it is difficult 

 to trace any curative effect from remedies. 



Opsonins.-^-Tbt opsonic index in the studies so far made 

 does not show any marked change from the normal. 



Virulent pneumococci are insusceptible to phagocytosis. 



Bacillus of Rhinoscleroma (Frisch, 1882). It was found 

 in the tissue of a rhinoscleroma, but resembles the Friedlander 

 bacillus in nearly every respect, and as the disease rhino- 

 scleroma is not reproduced by the inoculation of the bacillus 

 in animals, it can be considered identical. The growth, cul- 

 tures, and properties are the same as the pneumobacillus of 

 Friedlander. 



Diplococcus Intracellularis Meningitidis (Weichsel- 

 baum) . Origin. Found by Weichselbaum in epidemic cere- 

 brospinal meningitis in 1887. 



