496 



THE RESPIRATORY SYSTEM. 



involvement of the bronchial wall in inflammation with a direct exten- 

 sion of the process to the surrounding lung tissue has been urged espe- 



FlG. 276. BROXCHO-PXErMOXIA IX A CHILD. 



The section shows a single lobular area of consolidation with its bronchus whose thickened wall merges with 

 the surrounding zone of exudative pneumonia. 



cially by Delafield as the process to which the term broncho-pneumonia 

 should be par excellence applied. 



Between the consolidated areas there may be atelectasis of lung tissue 

 from the occlusion of the smaller bronchi with exudate. When the con- 

 solidated areas are situated at the surface of the lungs, fibrinous pleuri- 

 tis may be present over the affected regions. 



This form of broncho-pneumonia is frequent in children, sometimes 

 as an independent process, but often associated with or following diph- 

 theria, scarlatina, measles, etc. It oc- 

 curs also in adults, either as a compli- 

 cation of infectious diseases such as 

 typhoid fever, smallpox, influenza, etc., 

 or as a primary process. It may occur 

 in the aged or those enfeebled by chronic 

 wasting diseases. 



Resolution may take place in the 

 areas of broncho-pneumonia by proc- 

 esses of cell degeneration and absorp- 

 tion identical with those through which 

 restoration is secured in lobar pneumo- 

 nia. If, however, resolution in broncho- 

 pneumonia do not presently take place 

 and the lesion persist, dense connective 

 tissue is apt to form about the bronchi and in the interstitial tissue of 

 the lungs, which may lead to induration and distortion of the organs, 

 atelectasis, chronic bronchitis with dilatation of the bronchi, etc. A 



FiG.277. BROXCHO-PNEUMOXIA EXUDATE 

 IN A SIXGLE Am VESICLE. 



