IlXL'LAMMATlON. lOj 



sues in general are subject, arc common in inflamed tissues. 

 I'he following are the principal unes that have Ijeen descriljed. 



1. Parenchymatous degeneration (clondv swelling), is the most 

 common type in acute inflammatory tissues. It is indeed rare 

 to examine sections of tissue aitected with acute inflammation 

 and not find this degeneration. The presence of ])arcnchvmatous 

 degeneration is an additional factor freciuently resurted to in diff- 

 erential diagnosis ui inflammation. Tliis type of degeneration 

 occurs in all tissues, but more especially in glandular structures. 



2. Fatty degeneration does not occur as frc(|ucntly as paren- 

 chymatous degeneration. Like parenchymatous degeneration, 

 it occurs in tissues aliected with acute inflammation. It in- 

 variably occurs in combination with parenchymatous degenera- 

 tion and is usually a secjuel of the latter. The presence of fatt}' 

 degeneration in inflammatory tissue may cause confusion in 

 microscopic diagnosis, especially if the degeneration is exten- 

 sive. The degeneration is common in epithelium (glandular), 

 muscular tissue and connective tissue. 



3. Mucoid degeneration is quite common is inflamed tissues. 

 It is characteristic of catarrhal inflammation. This degenera- 

 tion affects the intercellular substance as well as the cells. 

 Mucus is bactericidal, therefore it is protectant and beneficial, 

 unless produced in suflftcient quantity to induce mechanical in- 

 jury. Epithelium and connective tissue are most frequently 

 affected by this degeneration. 



4. Serous degeneration, or more properly infiltration, is char- 

 acteristic of tissues affected with inflammatory oedema or other 

 inflammations in which there is excessive serous exudation. 

 This condition results from the passage into the cells of extra- 

 cellular serous fluid. The infiltrated fluid mechanically inter- 

 feres with the activity of the cell. It occurs most frequently 

 in muscular and connective tissue and occasionally in epi- 

 thelium. 



5. Hyaline degeneration is of common occurrence in tissues 

 affected with chronic inflammation. It is the conversion of the 

 tissue into a clear, waxy substance. It is common in the mus- 

 cular tissue of blood vessels in chronic inflammatory foci as 

 well as in fibrous tissue resulting from proliferative inflamma- 

 tion. 



6. Amyloid degeneration has been observed in chronic inflam- 

 matory tissues (Adami), although this is not a common sequel 

 of inflammation. 



An intercellular degeneration specifically affecting the ce- 

 ment substances between the myocardial cells has frequently 



