CHAPTER XVI 

 PNEUMONIA 

 LOBAR OR CROUPOUS PNEUMONIA 



DiPLOCOCCus Pneumoniae (Weichselbaum) 



Synonyms. — Micrococcus pasteuri, Diplococcus lanceolatus, Streptococcus 

 lanceolatus, Streptococcus mucosus, Bacterium pneumoniae, Bacillus septicus 

 sputigenus. 



Gener^ Characteristics. — A minute, spheric, slightly elongate or lancet- 

 shaped, non-motile, non-flagellate, non-sporogenous; aerobic and optionally 

 anaerobic, non-chromogenic, non-liquefying diplococcus, pathogenic for man and 

 the lower animals, staining by ordinary methods and by Gram's method. 



The micro-organism, that can be demonstrated in at least 90 per 

 cent, of cases of lobar pneumonia, which is almost universally ac- 

 cepted to be the cause of the disease, and about whose specificity 

 very few doubts can now be raised, is the Diplococcus pneumoniae 

 or, as it is most commonly called, the pneumococcus, of Frankel and 

 Weichselbaum. 



Priority of discovery of the pneumococcus seems to be in favor 

 of Sternberg,* who as early as 1880 described an apparently identical 

 organism which he secured from his own saUva. Pasteur f seems to 

 have cultivated the same micro-organism, also from saliva, in the 

 same year. Telamon,J Frankel, § and Weichselbaum, || however, 

 discovered the relation which the organism bears to pneumonia. 



Distribution.- — The pneumococcus is present in the lungs, sputum, 

 and'blood in croupous pneumonia. It is also found in the saliva 

 of a large number of healthy persons (Parke and Williams**), espe- 

 cially during the winter months (Longcope and Fox f t) , and the inocu- 

 lation of human sahva into rabbits frequently causes septicemia 

 in which the pneumococci are abundant in the blood and tissues. 

 Its frequent occurrence in the sahva led Fliigge to describe it as 

 Bacillus septicus sputigenus. It is occasionally found in inflamma- 

 tory lesions other than pneumonia, as will be pointed out below. 

 . Morphology.- — ^The organism is variable in morphology according 

 to the conditions under which it is examined. In the fibrinous 

 exudate from croupous pneumonia, in the rusty sputum, in the 



* "National Board of Health Bulletin," 1881, vol. 11. 



t " Compte-rendus Acad, des Sciences," 1881, xcii, p. 159- 



t "Compte-rendus de la Soci6t6 d' anatom. de Paris," Nov. 30, 1883. 



§ "Deutsche med. Wochenschrift," 188s, 31. 



II "Wiener med. Jahrbuch," 1886, p. 483. 

 ** "Jour. Exp. Med.," Aug. 7, 1905, vii, p. 403. 

 tt Ibid., p. 430. 



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