THE INFECTIOUS DISEASES. 



243 





when tubercle bacilli in moderate numbers lodge and develop in the liv- 

 ing body one of the early local effects is a proliferation of the connective- 

 tissue and endothelial cells. 1 These 



. become larger and polyhedral, with 



, '" s 'V * ". *\. conspicuous nuclei (Fig. 117). 



( \ '\ A new reticulum or stroma may 



form hand-in-hand with the growth of 

 these new cells, or the old stroma may 

 persist, adapting itself in form and 

 arrangement to the new conditions. 



Either after the connective-tissue 

 cell proliferation or hand-in-haud with 

 it," or preceding it, or altogether inde- 

 pendently of it, emigration of leuco- 

 cytes and extravasation of serum may 

 take place from blood-vessels in the 

 vicinity of the germs. During the 

 more or less active cell proliferation 

 which occurs under the influence of 

 the tubercle bacillus multinuclear cells 



giant cells may be formed (Fig. 118), either by persistent nuclear 

 division in growing protoplasmic masses which do not divide into sepa- 

 rate cells, or by the coalescence of the bodies of cells already formed. 





FIG. 117. A SMALL MILIARY TUBERCLE. 



This is growing in the liver ; is composed 

 mostly of new-formed polyhedral cells closely 

 packed with little intercellular stroma. At 

 the centre coagulation necrosis is commenc- 

 ing. 



FIG. 118. A MILIARY TUBERCLE WITH GIANT CELLS. 



Tnis tubercle is of the conglomerate type, made up of four granula, the larger one showing coagulation 

 necrosis in the central portion. From the peritoneum. 



More or less new tissue with numerous small spheroidal monouuclear 

 cells and little stroma may form in and about the tuberculous foci. 



1 The studies of Wechsberg indicate that in some cases at least the first effect of the 

 tubercle bacillus upon the living tissue is destructive, so that the characteristic cell pro- 

 liferation which follows may not be altogether due to a direct formative stimulus to cell 

 proliferation furnished by the bacillus. See Wechsberg, " BeitrRge zur Lehr. v. d. primaren 

 Einwirkung des Tuberkelbacillus," Ziegler's Beitrage zur path. Anat., Bd. xxix., 1901. 

 See further Herxheimer, Ziegler's Beitr., Bd. xxxiii., p. 363, Bibl. 



