DOSAGE OF TUBERCULIN. 45 



Of the three types of reaction the general and focal symptoms are the 

 most constant. Both are so characteristic for the existence of tuberculosis, 

 that their appearance justifies the diagnosis. In practice, however, it is the 

 general reaction, or almost exclusively the manifestation of fever, which is taken 

 as the guiding symptom. 



The focal reaction in all non-visible tubercular lesions is determined by 

 subjective methods, while increase in temperature is alone an objective 

 finding. 



In carrying out the tuberculin test, one must remember several practical 

 points which are of help for the correct interpretation of the results. These 

 may be summed up thus : 



Inasmuch as the rise of temperature is of diagnostic importance, no 

 patient with any fever should be subjected to the inoculation. For several days 

 previous the patient's temperature should be taken every three hours and 

 only if the temperature does not exceed 37 C. per axilla should the tuber- 

 culin diagnosis be undertaken. 



The quantity of tuberculin to be injected is also of the utmost consequence. 

 Too high doses should be avoided, as the specificity of this 



Dosage o reac ti O n, like all other biological reactions, is limited quanti- 

 Tuberculm. . ....... 



tatively. While small doses of tuberculin will give a rise 



of temperature only in tuberculous individuals, larger doses may give 

 the same rise even in healthy people. In addition, too large doses as a rule 

 may produce a general reaction which might be very severe and entirely 

 injurious. 



The dosage advised by Robert Koch for the diagnostic tuberculin reaction is 

 as follows: 



1. o.oooi c.cm. T. (for very weak individuals and children). 



2. o.ooi c.cm. T. 



3. 0.005 c.cm. T. 



4. o.oi c.cm. T. 



5. o.oi c.cm. T. 



The dose chosen at the first injection is as a rule i mg. T. Very weak 

 individuals, i.e., those in an advanced stage of tuberculosis or those who have 

 experienced a recent hemoptysis, as well as children should receive an 

 initial dose of only o.i mg. T. Bandelier and Ropke who have a wide experi- 

 ence in this field, advise 0.2 mg. T. as the primary dose. 



Few patients show a distinctly positive fever reaction even with this 

 small dose; by a positive reaction is meant an increase in the temperature 

 so that the latter is at least 0.5 C. higher than the highest point before the 

 injection. If the temperature has not increased, the reaction is negative, 

 and after an interval of two to three days of normal temperature the second 

 inoculation of 5 mg. T. is given. If it happens occasionally that after first 

 inoculation there is a doubtful reaction, i.e., there is an increase of 0.2 to 



