[On the possibility of a rapid method for sensitivity testing of mycobacteria by determination of H3-uracil incorporation (author's transl)].

Dubos-Tween Albumin cultures (8.0 ml) were set up with 10(6) viable bacteria per ml. After incubation for 48 hours 0.25 muC H3-uracil per ml was added. At the same time the antituberculoticum was introduced. The final concentrations were 1 microgram, 0.25 microgram and 0.025 microgram for INH; 4.0 microgram for SM; 32 microgram and 0.32 microgram for RMP; 2.0 microgram and 1.0 microgram for ETH; 0.5 microgram and 0.25 microgram for PAS. The incorporation rate clearly depended on the degree of sensitivity of the bacteria. Determing the incorporation rate of H3-uracil allowed the result to be read after only one week (fig. 1 and fig. 2) instead of 4 to 6 weeks using the conventional method on solid media. It was also found that turbidity measurements of the cultures (fig. 2) gave an equaly reliable result enabling this latter method to be performed in less well equipped laboratories.