BACILLUS OF DUCREY 425 



been demonstrated. Ordinary anilin dyes color the bacilli readily, 

 and the Gram stain is negative. 



Isolation and Culture. Growth occurs only in media containing 

 blood serum or ascitic fluid ; Loffler's alkaline blood serum is a favorable 

 substrate. The colonies on blood serum after twenty-four to forty- 

 eight hours' development at 37 C. are slightly sunken, due to the 

 liquefaction of the medium. After several days the serum is almost 

 completely liquefied. Colonies grown on ascitic agar are small, color- 

 less and transparent even after several days' incubation. Oxygen 

 is essential for the growth of the bacilli; no growth occurs when 

 oxygen is excluded from the media. 



Prognosis of Growth. A proteolytic enzyme which liquefies coagu- 

 lated blood serum is the only enzyme which has been described. No 

 other products of growth are known. 



Pathogenesis. Attempts to reproduce the characteristic subacute 

 conjunctivitis in experimental animals have utterly failed. In man 

 the typical disease is a subacute catarrhal conjunctivitis with com- 

 paratively little pus formation, differing in this respect sharply from 

 the acute conjunctivitis which is produced by the Koch-Weeks bacil- 

 lus. The angles of the eye are inflamed, particularly the caruncles. 

 The organisms are best detected in the secretion which collects during 

 the night. They occur both in pus cells and free, frequently in con- 

 siderable numbers. Morax appears to have reproduced the essential 

 lesions by inoculating a drop of culture upon a healthy conjunctiva. 



BACILLUS OF DUCREY. 



The soft chancre, chancroid, or soft sore must be sharply differen- 

 tiated from the hard chancre with which it has nothing in common. 

 The soft chancre is a non-specific, ulcerating sore common to both 

 sexes, particularly among the unclean. It begins as a small red spot 

 which rapidly develops into a pustule. This pustule soon breaks down, 

 leaving a spreading ulcer in which necrosis is a prominent feature. 

 The ulcer spreads with considerable rapidity and is difficult to control. 

 The adjacent and regional lymph glands usually become involved 

 and they soon soften and ulcerate. 



Ducrey 1 first called attention to a bacillus (which bears his name), 

 which he found regularly in chancroids. In 1900 Besancon, Griffon 

 and Le Sourd 2 succeeded in growing the organism in pure culture upon 



1 Monatsch. f. prakt. Dermat., 1889, ix, No. 9. 



2 Gaz. dcs Hop., 1900, No. 14; Ann. de Dcrmat. et Syph., 1901, ii, 1. 



