244 



OTHER ORGANISMS IN PNEUMONIA 



Friedliinder'n pncumobacillus. — This organism does, not occur alone in 

 more than about one per cent, of cases of pneumonia. In the sputum it 

 may appear as a very short diplobacillus possessing a capsule, but it also 

 frequently is seen in the form of long rods (Fig. 62). It stains by 

 ordinary methods, but loses the stain in Gram's method. 



It can be easily isolated on agar plat> s, on which it forms large whitish 



s ' > ,«&' +* ;iA 





Fig. 64. — Friedliinder's pneumobacillus, 1 

 from a young culture on agar, showing 

 some rod-shaped forms. 

 Stained with thionin-blue. x 1000. 



moist colonies resembling knobs of ivory. 

 On gelatine stabs, at the site of the puncture 

 the growth is sometimes heaped up above the 

 level of the medium, and along the needle 

 track there is a white granular appearance, 

 so that the 'whole may resemble a white 

 round-headed nail driven into the gelatin 

 (Fig. 63), but this appearance is not so fre- 

 quent as it is often stated to be. The gelatin 

 is not liquefied. The organism grows well 

 on all ordinary media, and on these its 

 bacillary nature is in marked evidence (Fig. 

 64). It may form capsules in sernm bouillon. 

 It is non-motile. It ferments glucose, lactose, 

 maltose, and mannite with acid and gas 

 formation ; the amount of acid formed from 

 lactose is often insufficient to clot milk. It usually can form indol from 

 peptone. The pneumobacillus is probably closely related to the b. coli. 

 When injected into mice and guinea-pigs it originates a septicaemia and 



1 The apparent size of this organism, on account of the nature of its sheath, 

 varies much according to the stain used. If stained with a strong stain, e.g., 

 carbol-fuchsin, its thickness appears nearly twice as great as is shown in the 

 figure. 



Fig. 63.— Stab culture of 

 Friedlander's pneumo- 

 bacillus in peptone 

 gelatin, showing the 

 nail-like appearance ; 

 ten days' growth. 

 Natural size. 



