PATHOGENESIS 47 



tures and thus creates a less favorable con- 

 dition. 



The duration of this stage Hke the former 

 one is variable. If the infection is acute and the 

 cyst wall thin, the abscess may ripen and burst 

 in a few days, while on the other hand if less 

 virulent and incarcerated in a thick wall, point- 

 ing may be delayed for weeks and even months. 

 When the abscess has once found a surface 

 exit and has discharged its contents, the disease 

 has passed into an entirely different stage, and 

 for a time the systemic condition improves. 



3. Fistulous Stage. This is fistula of the 

 withers. Heretofore the condition was fistula 

 only in name, now it is a reality. Heretofore 

 the course of the disease was guided solely by 

 internal influences, now it is exposed also to 

 secondary infections from without. It does not 

 matter whether the pointing was spontaneous 

 or whether an aperture was made artificially, 

 we now have to deal with a deep-seated cavity 

 that communicates freely with the outside 

 where reinfection will continue to occur, and to 

 make matters still worse the drainage is seldom 

 good enough to evacuate the contents entirely. 

 By remaining full of pus the cavity becomes a 

 fertile field for microbian growth and cicatrizes 

 very slowly. The pus-soaked walls of the cav- 

 ity becoming carpeted with undulating indol- 



