SPIROCH^TiE. 381 



remaining indolent for several weeks. The neighboring lymph 

 glands become swollen. The secondary manifestations occur 

 about a month later as a generfil macular or sometimes papular 

 eruption on the skin, together with sore throat and ulcerated 

 patches in mouth. The skin eruption does not itch. Subsequent 

 to this stage there may be local necrptic lesions (gummata) in 

 various parts of the body, or low-grade inflammatory changes in 

 the meninges and central nervous system. Bacteriological 

 methods of diagnosis are of assistance in some cases in all the 

 various stages of syphilis. Early in the disease the spirochetes 

 are relatively numerous, in certain locations at any rate, while 

 later the parasites may be so few as to render their detection 

 practically hopeless for diagnostic purposes. In these later 

 stages, however, the presence of specific and other antibodies in 

 the body fluids of the patient may often be recognized and this 

 recognition employed as an aid in diagnosis. 



Microscopic examination of a primary ulcer is best done by 

 means of the dark-field illumination. For this purpose the ulcer 

 (which should not have been treated with mercurials) is carefully 

 cleansed and a few drops of freshly exuded serum collected in a 

 glass capillary, and the usual slide-cover-glass preparation is made 

 with this fluid. Permanent preparations are made most easily 

 by mixing such serum with India ink on a slide and spreading 

 the mixture in a very thin layer. Collargol, one part in nineteen 

 parts of water, gives even more satisfactory preparations^ than 

 India ink. It is used in the same way. Thin films of the serum 

 on slides or cover-glasses may be stained as directed above. Micro- 

 scopic examination of fluid obtained by gland puncture or from 

 secondary lesions on the skin or mucous membranes is carried 

 out in the same way_. Serious confusion in the recognition of the 

 spirochete is likely to arise in the case of lesions in the mouth or 

 pharynx, inasmuch as some of the normal mouth spirochetes are 

 very similar in form to Sp. pallida. The presence of typical 

 spirochetes in the juice aspirated from a lymph gland is practically 

 ' Harrison: Journ. Roy. Army Med. Corps, 191 2, Vol. XIX, p. 749. 



