Blood Media for Determination of Sensitivity ofMycobacterium tuberculosisto Streptomycin

Abstract

Solid human blood media compare favorably with the Youmans liquid and the Herrold solid media for the detn. of sensitivities of tubercle bacilli to streptomycin. The results with both types of solid media were in closer agreement than those obtained with the liquid one. The tuberculostatic activity of streptomycin was not influenced by the amt. of blood in the medium. Concns. of 1, 5, 15 and 25% blood showed similar sensitivity endpoints and yielded equally good growth. The blood media described should be thoroughly investigated as vehicles for the detn. of the sensitivity of tubercle bacilli to all vars. of antibiotic and chemotherapeutic agents. For this purpose, blood agar base hydrated with approx. 1% glycerol and containing 1- 25% outdated bank blood, not older than 8 wks., is recommended.