CHAPTER V. 



PNEUMONIA. 







THE term "pneumonia," while generally understood 

 to refer to the lobar disease particularly designated as 

 croupous pneumonia, is a vague one, really comprehend- 

 ing a variety of inflammatory conditions of the lung 

 quite dissimilar in character. This being true, no one 

 should be surprised to find that a single organism cannot 

 be described as "specific" for all. Indeed, pneumonia 

 must be considered as a group of diseases, and the various 

 microbes found associated with it must be described suc- 

 cessively in connection with the peculiar phase of the 

 disease in which they occur. 



i. Lobar or Croupous Pneumonia. The bacterium, 

 which can be demonstrated in at least 75 per cent, of the 

 cases of lobar pneumonia, which is now almost uni- 

 versally accepted as the cause of the disease, and about 

 whose specificity very few doubts can be raised, is the 

 pneumococcus of Frankel and Weichselbaum. 



Priority of discovery in the case of the pneumococcus 

 seems to be in favor of Sternberg, who as early as 1880 de- 

 scribed an identical organism which he secured from his 

 saliva. Curiously enough, Pasteur seems to have cap- 

 tured the same organism, also from saliva, in the same 

 year. The researches of the observers whose names are 

 attached to the organism were not completed until five 

 years later. It is to Frankel, Telamon, and particularly 

 to Weichselbaum, however, that we are indebted for the 

 discovery of the relation which the organism bears to 

 pneumonia. 



The organism (Fig. 98) is variable in its morphology. 

 When grown in bouillon it is oval, has a pronounced dis- 



345 



