Papers on Medicine, Public He:alth and Sanitation 81 



So far as I could oberve in the making of thousands of 

 examinations, the number of tubercle bacilli present 

 bore no relation whatever to the physical condition of the 

 patient. Thus if the tubercle bacilli were present in the 

 sputum, the patient undoubtedly had tuberculosis. If the 

 tubercle bacilli were not present, the burden of proof 

 must then rest on the other means of diagnosis. 



The second was the skin test of Von Pirquet, in which 

 test, a small amount of Koch's old tuberculin is applied 

 to a scarification of the skin, or by interdermic injections. 

 This test was not used on tuberculous patients. However, 

 some experimental work w^as done on healthy soldiers 

 who volunteered, that we might determine the relation 

 of a positive Von Pirquet to the normal individual. In 

 these tests our observations were, that more than 95 per 

 cent of adults give a positive reaction. There was con- 

 siderable variation in the size and character of the react- 

 ing lesion, and the amount of tuberculin in a small per- 

 centage of cases had to be increased. 



Two conclusions from these experiments could be 

 drawn. First that the Von Pirquet has no diagnostic 

 value in adults and second, the reaction is probably in 

 proportion to the acquired immunity of the indi^ddual 

 against the tubercle bacillus.^* Spolverini applied this 

 test to 900 supposedly non-tuberculous children under 

 one year of age. He obtained a positive reaction in 7 

 per cent, .8 per cent positive at the age of four months, 

 2.4 per cent at six months, and the remainder, six to 

 twelve months. 



Third, the X-ray as a diagnostic means appeared to 

 have much value, not, however, in determining an un- 

 recognized tuberculosis, but in determining the extent 

 of the lesion, its exact location, and its retraction under 

 treatment when plates made at different periods were 

 compared. 



Roubier states in this connection on obserA^ation of a 

 thousand cases of tuberculous suspects, that with an act- 



w Observations which would have a bearing on the age at which the 

 child began to acquire tuberculosis, by L. M. Spolverini in Rivista di 

 Clinica Pediatrica, Florence, 1919. 



