34 2 Pneumonia 



PNEUMOCOCCUS (FRIEDLANDER*) BACTERIUM PNEUMONIA 

 BACILLUS CAPSULATUS Mucosus 



General Characteristics. An encapsulated, non-motile, non-flag- 

 ellated, non-sporogenous, non-liquefying, aerobic and optionally anaer- 

 obic, non-chromogenic, aerogenic and pathogenic bacillus, staining by 

 ordinary methods, but not by Gram's method. 



This organism was discovered by Friedlander in 1883 in 

 the pulmonary exudate from a case of croupous pneumo- 

 nia, and, being thought by its discoverer to be the cause of 

 that disease, was called the pneumococcus, and later the 

 pneumobacillus. The grounds upon which the specificity of 

 the organism was supposed to depend were soon found to 

 be insufficient, and the organism of Friedlander is at pres- 

 ent looked upon as one whose presence in the lung is, 

 in most cases, unimportant, though it is sometimes asso- 

 ciated with and is probably the cause of a special form 

 of lobular pneumonia, which, according to Stiihlern, is 

 clinically atypical and usually fatal. Frankel points out that 

 Friedlander 's error in supposing his organism to be the chief 

 parasite in pneumonia depended upon the fact that his studies 

 were made by the plate method, which permitted the dis- 

 covery of this bacillus to be made more easily than that of 

 the slowly growing and more delicate pneumococcus. 



Distribution. The organism is sometimes found in 

 normal saliva; it is a common parasite of the respiratory 

 apparatus, not infrequently occurs in purulent accumula- 

 tions, is occasionally found in feces, and sometimes occurs 

 under external saprophytic conditions. Thus it is probably 

 identical with that described as the "capsulated canal- water 

 bacillus" by Mori.|j 



Morphology. Though usually distinctly bacillary in 

 form, the organism is of variable length and when paired 

 sometimes bears a close resemblance to the pneumococcus 

 of Frankel and Weichselbaum. It frequently occurs in 

 chains of four or more elements and occasionally appears 

 elongate. It is these variations in form that have led to the 

 description of the organism by different writers as a coccus, 



* " Fortschritte der Medizin," 1883, 22, 715. 

 f'Spaltpilze," 1885, p. 66. 

 j"Centralbl. f. Bakt.," etc., xn, 1892, p. 304. 



"Centralbl. f. Bakt.," etc. (Originale), Bd. xxxvi, No. 4, p. 493, 

 July 21, 1904. 



|| " Zeitschrift fur Hygiene," iv, 1888, p. 53. 



