TUBERCLE 67 



The results obtained by this examination are somewhat un- 

 certain, as some of the other acid-fast bacilli found in milk are 

 almost exactly like the tubercle bacillus, and animal experiments 

 are necessary for definite proof. 



When/tgc« are to be examined, the best plan is to administer 

 opmm in amount sufficient to cause constipation. The surface 

 of the scybalous motions which result are to be scraped off and 

 stained in the usual way. Or the material may be examined by 

 the antiformin method. 



Interpretation of Results. 



The finding of tubercle bacilli in the sputum is conclusive 

 evidence of tuberculosis of the lungs, but no information as to 

 prognosis can be drawn from the numbers which are present; 

 they may occur in great quantities in the sputum from patients 

 who are doing well, and the author has found enormous numbers 

 in the sputum of a person who had presented no symptoms of the 

 disease for eight years, and was apparently cured. But a person 

 in whom the bacilli are present is always in danger of a recru- 

 descence of the disease, and may he a source of infection. Absence 

 of the bacilli does not disprove the diagnosis of tuberculosis; 

 bacilli do not appear in the sputum until the lung-tissue in which 

 they occur breaks down, and are therefore absent in the early 

 stages of acute tuberculosis. 



In some cases of ordinary chronic phthisis bacilli may. occur in 

 the sputum in very scanty numbers, and may be missed unless 

 a very careful search is made. Bacilli should not be considered 

 as being absent until well-stained films have been examined for 

 at least half an hour, and the examination repeated on several 

 occasions. It is in these cases that the carbolic method of 

 examination is so useful. 



The finding of tubercle bacilli in the urine is absolute proof 

 of tuberculosis of some part of the urinary tract, probably the 

 kidneys or bladder. Absence of bacilli implies nothing unless 

 the examination has been made very thoroughly and repeated 

 several times at intervals. Then it affords presumptive evidence 

 that the urinary passages are free from the disease. 



The same is true of the examination of pus. Tubercle bacilli 

 rarely occur in inflammatory exudates except in very small 

 numbers, and can often only be demonstrated by animal experi- 



