A Simplified Serological Test for Tuberculosis.

Abstract

Montank, 1 in 1924, reported before this Society the results of precipitation tests with tricresol on tuberculous serum. Vernes, 2 in 1923, applied his flocculation test to the study of tuberculosis and in 1926 published 3 the results obtained with the use of a resorcine reagent.

Prior to a description of the present test two points should be stressed: first, that it is based on the Vernes 4 principle of a periodic sinusoidal curve of precipitate; second, that it lacks the precision of the Vernes test and is in this way comparable to the Kahn test in its relation to other luetic reactions.

For the test, 0.5 cc. of centrifugalized blood serum, obtained from patient 3 hours after eating, is placed in a small clean tube and an equal quantity of a 1.25% aqueous solution of chemically pure resorcine in a duplicate tube. The contents of the tubes are then mixed rapidly, first pouring the resorcine on the serum. The tube containing the final mixture is securely stoppered and allowed to remain at an approximate temperature of 25° C. for 4 hours, followed by an over-night refrigeration. The following morning the test is read by inspection. According to the volume and character of the precipitate, results are expressed as minus, plus-minus, plus, 2-plus, 3-plus and 4-plus. There is also an atypical result observed in other pathological conditions, with or without concomitant tuberculosis, which is readily recognized by the large flakes of precipitate, different in character from the typical 4-plus reaction. The resorcine solution must be perfectly colorless, but hemolytic or slightly turbid serum may be successfully tested. During a period of 2 years 290 patients have been examined by this technic in conjunction with the more elaborate Vernes test.