NONSPECIFIC INFLAMMATION 313 



using aeid production in various sugars as a basis for this 

 classification. 



Pathogenesis. — Various strains of Streptococcus pyo- 

 genes show very great differences in their ability to produce 

 infection. Some strains are rleatively nonvirulent, others 

 are highly virulent. Some when inoculated into the body 

 tend to grow best in the blood stream, others grow in the 

 joints or in some particular organ of the body. In general 

 the disease produced is a more or less diffused inflammation. 

 In general infections with Streptococcus pyogenes are 

 somewhat more serious than those with staphylococci. 

 Apparently it is somewhat more difficult for the body to rid 

 itself of these organisms than of the other nonspecific pyog- 

 enic types. 



Focal Infections. — Streptococcus pyogenes when grow- 

 ing in the body is apt to develop in some particular tissue 

 or organ producing in it either an acute or chronic inflam- 

 mation. As will be noted below, organisms from such 

 chronic inflammations not infrequently pass to other parts 

 of the body, being carried there by the blood stream. A 

 few of the more important focal infections will be noted 

 briefly. 



Streptococci not infrequently produce chronic inflam- 

 mation of the tonsils (tonsilitis). From these they may 

 spread to neighboring lymph glands causing their enlarge- 

 ment or inflammation, sometimes resulting in the condition 

 known as quinsy. Chronic tonsilitis (as is true in chronic 

 inflammation of any part of the body) usually leads to the 

 formation of more or less cicatricial or scar tissue, the ton- 

 sils becoming hardened, and local areas of inflammation per- 

 sist. Occasionally the organisms pass to the middle ear, 

 probably by way of the Eustachian tube, causing the con- 

 dition known as otitis media. From this location the organ- 

 ism may also occasionally pass to the interior of the mastoid 

 bone (or rather the mastoid process of the temporal bone) 



