CHAPTER XV 



DIPHTHERIA 



THE diphtheria bacillus was discovered by Klebs, and 

 first isolated in pure culture by Loffler. It is, therefore, 

 usually spoken of as the Klebs-Loffler bacillus. It 

 is rather long and thin, frequently somewhat clubbed 

 at the ends, and possesses peculiar staining properties. 

 It is a non-motile, Gram-positive, strictly aerobic 



Fig. 28. Bacillus of diphtheria, fifteen-hour serum culture. Loffler's 

 methylene-blue; X 2000 (Denny, Journal of Medical Research). 



organism, and produces a powerful poison, diphtheria 

 toxin, when grown in broth cultures. 



The regions most frequently invaded by the diph- 

 theria bacillus are the tonsils and palate, the nasal 

 passages, and the larynx. The characteristic feature of 

 the inflammation produced by this bacillus is the forma- 



