584 TREPONEMATA, SPIEONEMATA, LEPTOSPIRATA 
the cerebral cortex of many cases of general paresis, and Renter^ has 
found the organisms in the walls of the larger bloodvessels in an 
individual infected with syphilitic aortitis. The Treponemata are 
present in enormous numbers in the liver, spleen and internal organs 
of cases of congenital syphilis. 
Bacteriological Diagnosis. — Co//prf?'on of Material.— The distribution 
of the organism in syphilitic tissues is quite irregular, the organisms 
being very numerous in some cases; in other, apparently similar cases 
so few in number that they may be readily overlooked. In congenital 
s>TDhilis the organisms are extremely numerous; in the lesions of 
acquired syphilis the organisms are best observed either in the primary 
or secondary stages. 
It is very important to make an early diagnosis. This may be accom- 
plished readily by a dark-field illumination of freshly drawn fluid from 
the suspected lesion. 
Primary Lesion.— Chan the surface of the chancre with brisk rub- 
bing, then make an abrasion in the skin deep enough so that there 
is an exudation of serum. J'ilms are prepared from this exudate. 
Secondary Lesion; Mncous Patches and Papvles. — Material is 
removed from the mucous patch after cleaning the surface, or from 
the papule by slight curetting. If the material thus obtained is too 
dense to spread readily it may be macerated in a drop or two of sterile 
ascitic fluid. 
1. Morphology.— The organisms may be seen in the living state 
with the dark-ground illuminating apparatus. The juice of a mucous 
patch or primary lesion is examined directly and the organisms appear 
on a black background as light yellowish closely coiled spirals, which 
are actively motile. The presence of Spironema (Treponema) refrin- 
gens must be borne in mind, this organism being frequently associated 
with Treponema pallidum. The former is thicker than Treponema 
pallidum, and the spirals are less numerous and coarser. The use of 
local antiseptics must, of course, be guarded against if an examination 
of the organisms in the living state is to be made. 
India Ink Method. ^The juice of a chancre or mucous patch is 
intimately mixed with India ink^ and a cover glass placed over the 
mixture. The organisms appear as white spirals against a black 
background. 
Other Staining Methods.— The material collected as above is spread 
on slides in thin layers and stained either by Schaudinn and Hoftmann's 
original method or by the silver impregnation method. (See Fontana 
stain, p. 200.) 
Method of Schaudinn and Hoffmann.— The films are fixed for fifteen 
to thirty minutes in absolute methyl alcohol or for a few seconds 
in the vapor of osmic acid, then they are stained from one to three 
1 Ztschr. f. Hyg., 1906, 54, 49. 
- Burri: Das Tuschverfahren, Jena, 1909. Hecht and Wilenko: Wien. klin. 
Wchnschr., 1909. 22, 932. 
