176 APPLIED IMMUNOLOGY 



The various methods utilized for the application of 

 tuberculin diagnostically comprise, (1) subcutaneous 

 injection, (2) intradermic injection, (3) cutaneous 

 scarification, (4) percutaneous anointment, and (5) 

 mucous membrane instillation. 



Method of Subcutaneous Injection, — First prac- 

 ticed by Koch, it supersedes in reliability any other 

 method of tuberculin application. Carelessness may 

 render it the most dangerous method, but properly 

 carried out it is absolutely harmless. It has been 

 variously modified as to size and interval of dosage. 

 Old tuberculin (O. T.) is the preparation of choice. 

 Koch stipulated that doses up to 250 milligrammes 

 could be administered to perfectly normal individuals 

 without reaction, but advised a limit of 10 to 25 milli- 

 grammes in practice. We feel that such doses are en- 

 tirely too large, and, with few exceptions, agree with 

 Roth-Schultz respecting the technic of inoculations. 

 The subcutaneous tuberculin test is best carried out 

 with the patient in bed or at rest. His temperature 

 and pulse should be recorded every two or three hours 

 for two or three days, also all clinical signs and symp- 

 toms must be noted prior to starting the first inocula- 

 tion. The primary injection given is 0.5 milligramme. 

 Should the slightest indication of a reaction, either 

 general, focal, or local (see page 174), supervene, the 

 same sized dose is to be repeated two or three days 



