THE TUBERCLE BACILLUS 611 



agent to early cases. No two institutions use tuberculin in exactly the 

 same manner, and it is, therefore, impossible to do more than outline the 

 general scheme of treatment. It must never be forgotten, however, 

 that all forms of tuberculin treatment consist in an " active immuniza- 

 tion " in which, for the time being, the toxemia of the patient is increased 

 rather than neutralized. It is obvious, therefore, that only cases in 

 which the process is not a very acute one, are at all suitable for treat- 

 ment. The general principle of modern tuberculin therapy seems to lie 

 in choosing doses so small that no marked general reaction shall follow. 

 The preparations most frequently employed are Koch's "Alttuber- 

 culin," his "TR," his "Neu Tuberkulin-Bazillen Emulsion/' and the 

 Bouillon filtre of Denys. Initial doses of Alttuberculin range from 0.1 

 to 0.01 of a milligram. In case of complete absence of a reaction, 

 the injection may be repeated, gradually increasing, about twice a week. 

 The occurrence of a reaction should be the signal for a longer interval 

 and a slower advance in the size of the dose. 



The initial dose of "TR" is, as advised by Koch, 64 about 0.002 mgm. 

 This usually causes no reaction. The dose is doubled, at reasonable 

 intervals, up to 1 mgm. After this, further increase is carefully gauged 

 by the clinical indications. The maximum dose is about 20 mgm. 



"Neu Tuberkulin-Bazillen Emulsion," 65 is begun with a dose of 

 0.001 mgm. Gradual increase as with the other preparations is then 

 practiced. The maximum dose is about 10 mgm. 



Bouillon filtre has been used chiefly by Denys 66 who claims ex- 

 cellent results. Denys is very emphatic in advising the absolute 

 avoidance of any reaction. He begins with a millionth or even the 

 tenth of a millionth of a cubic centimeter of the bouillon and increases 

 with extreme caution. His dilutions are made with glycerin broth. 



Active immunization with tubercle bacilli of reduced virulence has 

 been suggested and attempted at various times but, so far, without 

 definite success. No strikingly favorable results can be justly claimed 

 for any of these preparations. 



Passive Immunization in Tuberculosis. Numerous attempts have been 

 made to immunize tuberculous subjects with the sera of actively immune 



64 Koch, Deut. med. Woch., xiv, 1897. 



83 Bandelier and Eoeplce, "Lehrb. d. specifisch, Tub. Ther,/ 7 Wurzburg, 1908; 

 Koch, Deut. med. Woch., 1901. 



88 Denys, ' ' Le Bouillon filtre, ' ' Louvain, 1905. 



