746 Tuberculosis 



sible to prepare homogenized cultures of the tubercle bacil- 

 lus, and saw them agglutinated by the serum of immu- 

 nized animals and by the serum of tuberculous patients. 

 The subject was investigated by Koch,* who carefully 

 reviews the details of technic and investigates the method, 

 which, he concludes, is valueless for the diagnosis of human 

 infection, though a good guide to the extent of immunization 

 achieved by the therapeutic administration of tuber culin-R. 

 Thellingf has also shown the reaction to be too irregular 

 to be of practical diagnostic importance. 



The technic of the agglutination test as given by KochJ 

 is as follows : 



Any culture of the tubercle bacillus can be made useful by the fol- 

 lowing treatment: Collect the bacillary masses upon a filter-paper 

 and press between layers of filter-paper to remove the fluid. Weigh 

 out, say, 0.2 gm. of the solid mass and rub it in an agate mortar, adding, 

 drop by drop, a ^V normal sodium hydroxid solution until the proportion 

 of i part of the culture to 100 parts of the solution is reached. 



It is necessary that the rubbing be thorough in order that the firm 

 connection between the bacilli shall be broken up and the organisms 

 distributed throughout the fluid. The operation usually lasts fifteen 

 minutes. The fluid is then placed in a hand centrifuge and whirled 

 for six minutes, then pipeted off, and rendered feebly alkaline by adding 

 diluted hydrochloric acid solution. The fluid thus obtained is too con- 

 centrated to be used in this form, so must be diluted with 0.5 per cent, 

 carbolic acid in 0.85 per cent, sodium chlorid solution. This solution 

 should be repeatedly filtered before receiving the bacillary suspension. 

 The quantity of bacillary suspension to be added should make the final 

 product a 3000 dilution of the original. It should look like water by 

 transmitted light, but slightly opalescent by reflected light. 



The serum to be tested is added in proportions of i : 10, i : 25, i : 50, 

 i : 75, i : 100, i : 200, i : 300, etc., and is to stand for twenty-four hours. 

 By inclining the tube and looking through a thin stratum of the fluid 

 the agglutinations can be at once detected. 



Antitubercle Serums. Tizzoni and Centanni, Bern- 

 heim,|| Paquin,** Viqueratff and others have experimented 

 in various ways, hoping that the principles of serum therapy 

 might apply to tuberculosis. Nothing has, however, been 

 achieved. Maragliano's|t antitubercle serum has been used 



* "Deutsche med. Wochenschrift," 1901, No. 48, p. 829. 



f Loc. cit. 



t "Deutsche med. Wochenschrift," 1901, No. 48, p. 829. 



"Centralbl. f. Bakt.," etc., Bd. xi, p. 82, 1892. 



|| Ibid., Bd. xv, p. 654, 1894. 

 ** "New York Med. Record," 1895. 



ft "Zur Gewinnung von Antituberkulin, Centralbl. f. Bakt.," etc., 

 Nov. 5, 1896, xx, Nos. 1 8, 19, p. 674. 



it "Berliner klin. Wochenschrift," 1895, No. 32. 



