[Comparison of susceptibility testing results of M. tuberculosis by different methods].

ABSTRACT

OBJECTIVE: To compare the susceptibility testing results of M. tuberculosis detected with different standards and methods. METHOD: 158 strains of M. tuberculosis isolated from clinical patients were detected for the drug sensitivity by Chinese standard and method (absolute concentration method), 1% resistance ratio and absolute concentration method of WHO/IUATLD standard. RESULTS: The drug-resistant rate detected by the standard of WHO/IUATLD was 53.8%(85/158), while by the Chinese standard 50.0%(79/158). The drug-resistant rates to INH, SM, EMB and RFP by WHO/IUATLD standard were 41.8%(66/158), 34.2%(54/158), 22.1%(35/158) and 27.8%(44/158) respectively, whereas by the Chinese standard 34.2%(54/158), 30.4% (48/158), 18.4%(29/158) and 27.2%(43/158) respectively. There was no significant difference between the results detected with WHO/IUATLD and Chinese standard, except for the results of INH. There was no significant difference between the results detected with WHO/IUATLD standard by 1% resistant ratio and absolute concentration methods. CONCLUSION: The results of drug-sensitivity were interfered by the detected standards but not by the tested methods.