INFLAMMATION. 61 



What is diphtheritic inflammation of mucous surfaces ? 



By some this form is regarded as the same as the croupous 

 variety. 



The hypersemia seems more intense, the infiltration more ex- 

 tensive, the fibrinous exudation more abundant and granular; great- 

 er changes take place in the epithelial and tissue cells, the membra- 

 nous exudation cannot be removed without a loss of substance, and 

 multitudes of bacteria, especially the micrococci, are found on the 

 surface and in the infiltrated tissues beneath. Sometimes the press- 

 ure is so great as to cut off the nutrition, the part dying and slough- 

 ing away. 



What is meant by a parenchymatous inflammation ? 



In this form the cells proper of the organs — that is, the cells 

 which perform the function — are the parts affected. 



In acute parenchymatous inflammations what takes 

 place ? 



If mild, the cells increase in size, are granular, opaque, and 

 their functional activity is increased; the blood-vessels contain more 

 blood, the stroma is infiltrated with serum, and the affected organ 

 is slightly increased in bulk, which, however, returns to the normal 

 if resolution takes place. 



If the inflammation be intense in character and prolonged, 

 the cells are destroyed, the circulation checked, the stroma is in- 

 filtrated with serum and pus, the organ increased in size, of a 

 purplish color, and the functional activity arrested. Fatty change 

 takes place and the cells disintegrate, the walls of the blood-vessels 

 become thicker, the calibre lessened or obliterated, the stroma 

 increased on account of the new tissue being formed, the function 

 becomes impaired and never returns to the normal, owing to the 

 permanent changes. 



Describe an interstitial inflammation. 



The connective tissue of the organ becomes affected. If acute, 

 suppuration usually occurs, which is limited to small areas, or it 

 may be diffused. If only a few pus-cells form, resolution is pos- 

 sible, while if many pus-cells are present abscesses develop which 

 have firm walls. If chronic, which is generally the case, it ends in 

 induration and cirrhosis by the formation of new connective tissue 

 without the formation of pus. The new tissue corresponds in kind 

 to the original stroma of the organ, and is permanent, the affected 

 organ never returning to the normal. 



