Staining 705 



5. Wash quickly in water. 



6. Dry. 



7. Mount. 



The entire process takes about three minutes. The tubercle bacilli alone 

 remain red. 



The possible relation that the number of bacilli in the expectora- 

 tion of consumptives might bear to the progress of the disease was 

 investigated by Nuttall.* 



But a glance down the columns of figures in the original article 

 is sufficient to show that accident may cause wide variations in the 

 quality of the sputum and the number of bacilli it contains. 



Staining the Bacillus in Urine. — The detection of tubercle bacilli 

 in the urine is sometimes easy, sometimes difficult. The centrifuge 



Fig. 278. — Bacillus tuberculosis in sputum, stained with carbolic fuchsinand 

 aqueous methylene-blue. X 1000 (Ohlmacher). 



should be used and the collected sediment spread upon the glass. 

 If there be no pus or albumin in the urine, it is necessary to add a 

 littie white of egg to secure good fixation of the urinary sediment 

 to the glass. The method of staining is the same as that for sputum 

 but as the smegma bacillus (q.v.) is apt to be present in the urine, 

 the precaution should be taken to use Pappenheim's solution for 

 differentiation or to wash the stained film with absolute alcohol, 

 that it may be decolorized and confusion avoided. 



Staining the Bacillus in Feces. — It is difficult to find tubercle 

 bacilli in the feces because of the relatively small number of bacilli 

 and large bulk of feces. 



* "Bull, of the Johns Hopkins Hospital," May and June, 1891, 11, 13- 

 4S 



