HAMBURGER'S LOCAL REACTION 47 



[The local reaction has been recently advocated by Hamburger as a 

 very delicate diagnostic method. He carries out the test as follows: 

 i/io c.cm. of a i: 10,000 dilution of tuberculin is injected just beneath 

 the skin of the forearm or back. The needle should be of fine caliber and 

 the syringe should never have been used for more concentrated solutions 

 of tuberculin. If the reaction is positive a subcutaneous infiltration 

 appears within twenty-four hours. Furthermore, there is a reddening 

 at the site where the point of the needle rested (" Depot reaction" of 

 Hamburger). 



If there is no reaction within twenty-four hours, i/io c.cm. of a dilu- 

 tion i : 100 should be injected. 



This subcutaneous local reaction may also be carried out in the form 

 of an intracutaneous test (see later)]. 



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 in Koch's subcutaneous method. 



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 subcutaneous 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 

 osage o reac tion, like all other biological reactions, is limited quanti- 

 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 

 produce a general reaction which might be very severe and 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. 



