54 



TUBERCULIN DIAGNOSIS. 



In regard to the specificity of the ophthalmo reaction, the condi- 



, tions here are more favorable than in both of the preceding 



of Ophthalmo A , 

 Reaction tuberculin tests. The following short chart is explanatory. 



Positive reactions were obtained in 



Calmette's preparation, 



i% old tuberculin. 



It is evident from the above figures that by the use of the i per cent, tuber- 

 culin a grade of specificity is reached which can be considered quite high, as 

 the non-tuberculous react only in a very small percentage of cases, while existing 

 tuberculosis is detected in 80 per cent, of the subjects. Clinical examinations 

 of the positive reacting patients show that the latter belong to the group of 

 active tuberculosis. Absolute reliance, however, in the determination as 

 to whether the positive reaction given is due to an active or latent tuberculosis, 

 cannot even be placed upon the ophthalmo reaction. 



According to several authors, it is claimed that typhoid fever, rheumatism, and 

 syphilis (in the stage of eruption) are very prone to give a positive ophthalmo reaction, 

 without the presence of a simultaneously existing tuberculosis. 



In conclusion, therefore, the author finds it difficult to make any general 

 statement as to the preference of one or the other reaction test for diagnostic 

 purposes. 



In children, however, it may be said that the application of the Pirquet 

 reaction, in adults, the ophthalmo reaction, are given preference to Koch's 

 reaction, provided no contraindications exist against the former, and that 

 treatment with tuberculin is not to be undertaken. In the latter instance, 

 the recurrent ophthalmo reaction when the tuberculin therapy is instituted, 

 authorizes the use of Koch's subcutaneous diagnostic method. 



Mallein, Trichophytin. 



Similar to old tuberculin, the Mallein (Helmann and Kelning) has been obtained 

 from cultures of Glanders bacilli and the Trichophytin (Plato) has been isolated from 

 the Trichophyton fungi. Mallein has already attained a place in practical application 

 for the diagnosis of glanders in veterinary medicine. Like tuberculin it is harmless in 

 normal organisms, but brings about temperature and a local reaction at the site of the 

 injection when inoculated into glanders stricken animals. Various general symptoms 

 may also appear. Its employment in a manner analogous to the ophthalmo reaction 

 is also possible. 



