[Skip to Content]
[Skip to Content Landing]
Article
September 16, 1922

A RING OR CONTACT PRECIPITATION TEST FOR SYPHILIS: A MODIFICATION OF THE KAHN TEST

Author Affiliations

CHICAGO
From the John McCormick Institute for Infectious Diseases.

JAMA. 1922;79(12):957-958. doi:10.1001/jama.1922.02640120031011
Abstract

Several precipitation tests for syphilis have been described recently, the latest and simplest being that of Kahn.1 At present I wish to describe briefly a modification of Kahn's test by using the ring or contact method employed with success in the work on specific precipitins in this institute during the last several years.

This ring or contact test for syphilis may be made as follows: A small amount, say 0.1 c.c., of cholesterolized antigen prepared as described by Kahn, diluted 1: 12 with physiologic sodium chlorid solution, is placed in a small glass tube, about 0.5 mm. in diameter and from 3 to 4 cm. in length, by means of a pipet (Fig. 1); approximately the same quantity of the serum to be tested, undiluted and unheated, is then introduced slowly in another pipet at the bottom of the tube so that a precise line of contact forms between

×