THE RESPIRATORY SYSTEM. 497 



photograph of a section of such a chronic or "persistent" oroncho- 

 pneunionia is reproduced in Fig. 279. 



Other Forms of Lobular and Broncho-Pneumonia. There are forms or 

 types of lobular pneumonia in which serum and epithelial cells with 

 more or less fibrin and leucocytes collect in the air spaces of a limited 

 region without primary bronchitis and without involvement of the walls 

 of the bronchi and air spaces. 



In one type of lobular pneumonia and broncho-pneumonia the exu- 

 date may consist largely of pus cells which infiltrate the walls of the air 

 spaces and bronchi as well as fill the air spaces themselves. This type 

 of inflammation may be induced by the aspiration in feeble persons of 

 irritating substances or bacteria-containing material of various kinds, 



FIG. 278. BRONCHO-PNEUMONIA CHILD. 



Showing slight change in the epithelum of the bronchus ; a purulent exudate in the lumen ; thickening of 

 the wall of the small bronchus, and exudate in the adjacent air vesicles. 



particles of food, saliva, etc. This is called aspiration pneumonia and 

 may result in uecrotic or gangrenous processes in the involved regions 

 of the bronchi and lungs. Again there may be circumscribed areas of 

 exudative pneumonia, often suppurative in type and involving the walls 

 of the air spaces, which originate through the transportation by the 

 blood-vessels of various forms of bacteria, especially the Streptococcus 

 and Staphylococcus pyogenes, as in pyaemia ; this is called lobular pneu- 

 monia of heematogenous origin or pycemic pneumonia. Thus abscesses of the 

 lungs may be formed. 



In the lobular pneumonia of bubonic plague the exudate is said to 

 contain few leucocytes and epithelial cells and to consist largely of blood 

 and plague bacilli. l 



In the aged or those long in bed in an enfeebled condition, hyperse- 



1 Consult Flexner, Trans. Assn. Am. Phys., vol. xvi., 1901 

 32 



