Background and Aim: Time - consuming in reporting the antibiotic determination result is the most challengeable bottleneck based on proportional method in Mycobacterium Tuberculosis diagnosis labs. To overcome this problem, we hypothesized that concentrated s amples (grade from 1+ to 3+) can be applied instead of colonies from same sample.
Methods: In this study 38 positive samples (treatment control and diagnostic group) decontaminated by Petroff method and resulted concentrated samples were used as direct pro portional to antibiotic resistance determination. By inoculation of precipitant to Lowenstein - Jensen Medium containing Isoniazid and rifampin antibiotic, colonies were compared with the lacking - antibiotic blank and rate of resistance calculated at the cr itical point 1%.
Results: Results from comparison of gold standard direct and indirect methods revealed a significant difference for isoniazid and rifampin resistance. Specifity and sensitivity were not significant between two methods. Sample reporting in direct method in diagnostic sample group was between 15 to 25 days and for treatment control group were 20 to 30 days. The expecting time needed for reporting the test reduced up to 50%.
Conclusion: Based on urgent situation, both direct and indirect metho d can be used in parallel in Mycobacterium tuberculosis centers.