Bacillus Pneumoniae, Friedlander (1883). 



FKIEDLANDEE'S PNEUMOCOCCUS, OB PNEDMO-BACILLUS. 



Origin. — It is frequently found in normal saliva; also- in the lung's 

 and in the "rusty " sputum of pneumonia. May occur elsewhere as in 

 otitis. It has been found in the air and in water. 



Form. — In the exudates from the body it may appear as an oval 

 coccus, but in reality it is a short, thick rod, which may grow in pairs 

 and even in short threads. In the animal body it is enveloped by a 

 well-marked capsule. This is not present in artificial cultures. 



Motility. — It has no motion. 



Sporulation. ^Spores have not been observed. Cultures retain 

 their vitality for many months. 



Anilin dyes.— 'ifhe cell is stained readily but the capsule remains 

 colorless. The bacillus is not stained by Gram's method — distinction 

 from Frankel's diplococcus. 



Growth. — Is rapid and abundant. 



Plates.^ — On gelatin plates it develops rapidly. The deep colonies are round or oval, 

 sharply bordered; finely granular and yellowish. The surface colonies are quite character- 

 istic and appear as thiols, moist, glistening, white masses which do not tend to spread but 

 rather tend to become convex and raised! This appearance is more marked when grown 

 at 15° than when developed at25°. In the latter case, they may be flat and irregular. No 

 liquefaction. 



Stab culture. — Growth takes place along the entire line of inoculation and is espec- 

 ially developed on the surface forming a " naif-shaped " culture. As the culture becomes 

 old the gelatin near the surface becomes brownish ra color and small gas bubbles may form. 



Streak culture. — On agar, it forms a thick, mucus-like, whitish or transparent, moist, 

 slimy growth. On blood-serum develops as a grayish, slimy mass. On fotato it forms a 

 thick, yellowish, sticky growth, which shows gas bubbles. A diastatic ferment is present. 



Bouillon is rendered diffusely cloudy. 



Milk is not coagulated, or but rarely. Indol is not produced. 



Oxygen requirements. — It is a facultative anaerobe. 

 Temperature. — It grows rapidly even at low temperatures, 16-20°; 

 best growth in the incubator. 



Behavior to gelatin.— It does not liquefy. 



Aerogenk.sis. — Abundant production of gas in 4 per cent, gelatin. 

 Potato cultures grown in the incubator also give rise to gas. . 



Pathogenesis. — It is pathogenic for mice and young rats. Guinea- 

 pigs, rabbits and dogs are less susceptible. The virulence varies 

 considerably. 



The Friedlander bacillus is unquestionably capable of inducing 

 pneumonia. However, it is only in a relatively small percentage of 

 cases that it may be looked upon as the cause. It is frequently asso- 

 ciated with the diplococcus pneumoniae, thus giving rise to a mixed 

 infection. This organism is, moreover, an etiological factor at times 

 in other inflammatory diseases, such as angina, pleuritis, pericarditis, 

 endocarditis, otitis, suppurative peritonitis, etc. 



Diagnosis. — The bacillus pneumonias resembles very closely that 

 of ozena, and of rhinoscleroma. Moreover, it must be carefully 

 distingushed from certain varieties of the colon bacillus (B. aero- 

 genes). Glycerin agar plates, grown at 37°, should be resorted to for 

 the detection of the Friedlander and Friinkel germs in suspected 

 material. 



1 Make gelatin plates and cover-glass preparations from the lungs and blood of a 

 voung rat which has received an intrapleural injection. 



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