CORYNEBACTERIUM DIPHTHERIA. 397 



mtains living diphtheria bacilli (except from a moment- 

 ary contamination by the coughing of the patient — Flugge). 



(6) In healthy body : Sometimes found in the mouth and 

 nasal cavities, also in the conjunctival sac of healthy per- 

 sons, especially in those coming in contact with diphtheria 

 cases. In a diphtheria epidemic in a barracks, Aaser 

 found diphtheria bacilli in the throats of 19% of the occu- 

 pants who were healthy. 



(c) In diseased human organism : Are found without ex- 

 ception on the outer side (the side toward the cavity of 

 the mouth) of the diphtheritic membranes 1 of recently 

 affected men, and with more difficulty and less regularly 

 in chronic cases. 



Principal localizations : Throat, nose, larynx, trachea ; 

 more rarely, stomach, defects in skin and muscle (wounds), 

 and vagina. 



The wide-spread assumption that the diphtheria bacilli 

 are to be found only at the local seat of disease is un- 

 founded. Lately they have been found rather frequently 

 (also in man) in the blood and internal organs, especially 

 the spleen and kidney (Frosch, Z. H. xiii, 49; Nowak, 

 C. B. xix, 982). Recently also rhinitis fibrinosa, conjunc- 

 tivitis crouposa (severe and very mild forms), and many 

 middle- ear suppurations have been traced to the diph- 

 theria bacillus. 



Almost regularly the Streptococcus pyogenes accom- 

 panies the diphtheria bacillus (Loftier) and in the patho- 

 logic process plays a synergistic role. 



Regarding the significance of mixed infection, Bernheim 

 has ascertained : 



1. The metabolic products of the streptococci favor the 

 growth of diphtheria bacilli and increase the virulence ; 

 also the production of toxin by the diphtheria bacillus is 

 increased (Hilbert, Z. H. xxix, 157). 



1 Diphtheritic angina also occurs without formation of membrane. 

 On the other hand, not rarely clinical " diphtheria cases," in spite of 

 a perfectly typical local symptom-complex, present no diphtheria 

 bacilli (according to Escherich, in Gratz about 25%). A number of 

 other organisms (for example, streptococci) can cause the symptoms of 

 diphtheria of mucous membranes. The mortality in these cases is 

 minimal. Also "wound diphtheria" may depend upon streptococci 

 or Bact. coli, 



