CHAPTER X 

 CHANCROID 



Bacillus Ducreyi 



General Characteristics.^ — A small, ovoid streptobacillus, with rounded, deeply 

 staining ends, non-motUe, non-flagellate, non-sporogenous; aerobic and optionally 

 anaerobic, non-chromogenic, staining by ordinary methods, but not by Gram's 

 method, cultivable on special media only and pathogenic only for man and certain 

 monkeys. 



The chancroid, soft chancre, or non-specific sore, as it is called, 

 is a common venereal affection of both sexes, most frequent among 

 those who give little attention to cleanliness. It is characterized 

 by the appearance of a soft reddish papule, which makes its appear- 

 ance usually upon the gen'ital organs, rarely upon other parts of the 

 body, soon after the infection, and soon becomes transformed to an 

 ugly ulceration whose usual tendency is toward slow and persistent 

 enlargement, though in different cases it may be indolent, active, 

 phagedenic, or serpiginous. The inguinal or other nearby lymph- 

 nodes early enlarge, and soon soften and ulcerate. The disease is, 

 therefore, extremely destructive to the tissues invaded, though no 

 constitutional involvement ever takes place. 



Specific Organism. — In 1889 Ducrey* described a peculiar organ- 

 ism whose presence he was able to demonstrate with gre^t con- 

 stancy, sometinies in pure culture, in the lesions of chancroid, and 

 which he believed to be the specific organism of the affection. Unnaf 

 later described an organism resembling that of Ducrey, and the later 

 observations of Krefting,J Peterson, § Nicolle,|| Cheinisse,** and 

 Davis ft have abundantly confirmed the observations of Ducrey and 

 Unna, and proved the identity of the two micro-organisms and 

 their specificity for the disease. 



Morphology. — The organism is commonly described as a "strepto- 

 bacillus." It is very small, short, and ovoid in shape, and occurs 

 habitually in longer or shorter chains. Each organism measures 

 about 1.5 X 0.5 ij.. The ends are rounded and stain deeply. In 

 pure cultures long undivided filaments, at least twenty times as 

 long as the individual bacilli, are not uncommon. There seems to be 



*"Congres. Inter, de Dermatol, et de Syphilog.," Paris, 1889; "Compt- 

 rendu," p. 229. 



fMonatschr. f. praktische Dermatologie," 1892, Bd. xiv, p. 485. 

 X "Archiv. f. Dermatol, u. Syphilol.," 1897, p. 263; 1897, p. 41. 

 § "Centralbl. f. Bakt.," etc., 1893, xra, p. 743. 

 I] "Med. Moderne," Paris, 1893, iv, p. 735. 

 ** "Ann. de Dermat. et de Syphil.," Par., 1894, p. 272. 

 tt "Jour. Med. Research," 1893, ix, p. 401. 



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