SPECIFIC BACTERIAL REACTIONS 



177 



after its subsidence. If no sign of a reaction occurs, 

 the dose may be increased to 1.25 milligrammes on the 

 third day. Again if the typical reaction is not pro- 

 duced and merely suggestive signs appear, the same 

 sized inoculation is repeated, since this may be suffi- 

 cient to provoke a marked reaction after the previous 

 sensitization. In the absence of any reactive phe- 



Fig. 15. — Edward G., aged 77. Tuberculous mastoiditis. Note typical diagnostic 

 tuberculin reaction after second injection of tuberculin. Associated with the febrile 

 rise and general reactions of malaise and headache, was a local reaction of increased 

 pain and discharge from the mastoid. 



nomena after three or four days, an injection of 2.5 

 milligrammes should be given. If this fails to cause a 

 definite response, a final maximum inoculation of 5 

 milligrammes is permissible. In children, under fifteen 

 years of age, Baldwin recommends doses of 0.05, 0.2, 

 0.5 and 1 milligramme. A reaction to be pathogno- 

 monic for any suspected lesion must comprise, in 



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