KOCHS TUBERCULIN TREATMENT 149 



w^as then evaporated down to one-tenth of its bulk on a 

 water-bath. The result was tuberculin, and would contain 

 the bacterial products such as would not be destroyed at 

 100° C. 



The injection of 0'25 c.c. of tuberculin into a healthy 

 individual induces in three or four hours laboured breath- 

 ing, malaise, and moderate pyrexia, all of which effects pass 

 off in twenty-four hours. The injection, however, of as 

 little as O'Ol c.c. into a tubercular person gives rise to 

 similar symptoms in a very much more aggravated form, 

 great inflammatory reaction and necrosis occurring round 

 the tubercular focus, resulting in a casting off of the 

 tubercular mass. This is well seen in the case of lupus. 



The publication of Koch's results in 1890 raised great 

 hopes that a means of combating tuberculosis had been 

 discovered, and in the case of lupus the treatment certainly 

 appeared to be attended with some success. This remedy, 

 although it has not fulfilled what was expected of it, has at 

 any rate been the means of bringing to notice the possibility 

 of combating disease by injecting into the patient toxins 

 ready-made which are liberated in the ordinary course of 

 disease, and has led the way to the investigation of anti- 

 toxin treatments in diphtheria, cholera, etc. 



It has also been found of use in the diagnosis of tubercle. 

 If, however, it be injected into a patient in whom phthisis 

 is dormant, it is very apt to cause the old trouble to break 

 out afresh. 



In the diagnosis of tuberculosis in cattle it is very 

 valuable, the failures being only about 2 per cent. The in- 

 jection of O'OS c.c. causes a rise of temperature of 2° to 3° F. 

 above the normal in from eight to twelve hours. 



Koch has recently (April, 1897) published the results of 

 his later researches on tuberculosis. He found that tubercle 

 bacilli contain two fatty acids of different solubility in 



