METHODS OF DIAGNOSIS. 267 



owing to failure to cultivate the organism outside the 

 body. 



Methods of Diagnosis. Film preparations should be 

 made with the discharge from any ulcerated nodule which 

 may be present, or from the scraping of a portion of excised 

 tissue, and should be stained as above described. The 

 presence of large numbers of bacilli situated within the 

 cells and giving the staining reaction of leprosy bacilli, 

 is conclusive. It is more satisfactory, however, to make 

 microscopic sections through a portion of the excised tissue, 

 when the structure of the nodule and the arrangement of 

 the bacilli can be readily studied. The points of difference 

 between leprosy and tubercle have already been stated, 

 and in most cases there is really no difficulty in distinguish- 

 ing the two conditions. 



