A Rapid Method of Determining Streptomycin Sensitivity of Mycobacterium tuberculosis

FOR some time now we have been using slide-culture of tubercle bacilli¹ in Youmans medium² as a direct method of testing streptomycin sensitivity of these organisms in sputum. The great advantage of this method over those previously described^3-7 lies in its technical simplicity and rapidity. Giammalvo, Natsios and Elton⁸ have recently described the use of the slide-culture in this connexion; but they worked with pure cultures requiring four to six weeks preparation and involving extensive manipulation of the culture. By contrast, using the method outlined below, a result can be obtained in seven days provided tubercle bacilli can be seen in the untreated specimen (sputum) by direct smear.