Pathogenesis 717 



Inoculation has, so far, failed to reproduce the disease either in 

 man or in the lower animals. 



Pathogenesis. The bacillus is said to be pathogenic for man only, 

 producing granulomatous formations of the skin and mucous 

 membranes of the anterior and posterior nares. These vary in 



* * *~ * X fc 



*\V / "- 1 ^4^- 



Fig. 294. Bacillus rhinoscleromatis. Pure culture on glycerin agar-agar. Mag- 

 nified 1000 diameters (Migula). 



structure according to age. The young nodes consist of a loose 

 fibrillar tissue composed of lymphocytes, fibroblasts, and fibers. 

 Some of the cells are large and have a clear cytoplasm and are 

 known as the cells of Mikulicz. In and between them the bacilli 

 are found in considerable numbers. The older lesions consist of a 

 firm sclerotic cicatricial tissue. 



