Mods Applied Research In Culture And Drug Sensitivity Determination Of Mycobacterium Separation

Mycobacterium tuberculosis grows faster in liquid medium than in solid medium; and which will show the characteristic cord formation in the fluid medium,we will see it clearly by invert microscope with lower magnification. MODS,which use the invert microscope to decide the positive for M. tuberculosis cultures through observing the distinct hypha in the drug-free wells,and decide the drug susceptibility through contrasting the growth condition of M. tuberculosis in the drug-free wells and drug-containing wells.In this work,we assessed the MODS clinical value of diagnosis,treatment and patients'management during the M. tuberculosis isolated cultures and drug susceptibility assay. The research cultured 113 patients'sputum specimen,and the positive specimen were directly detected of drug-susceptibility on isoniazid,rifampicin,streptomycin and ethambutol simultaneously. The results were analyzed contrasted with conventional culture on LÇ’wenstein-Jensen(L-J) medium and absolute concentration method on drug susceptibility testing of M. tuberculosis,and further detected the drug susceptibility with analyzing the drug resistance gene sequencing.The data manifested the positive rates of MODS and conventional culture on LÇ’wenstein-Jensen(L-J) medium were both 83.2%,the coincidence rate was 93.6%(kappa value: 0.75),the contaminated rate was 0% and 2.7%,both were no significant difference. The sensitivity and specificity of MODS were 95.7% and 81.3% respectively. The median time to culture positivity of MODS was 10 days(the 95% percentile was 21.5 days) and LJ was 25 days(the 95% percentile was 39.3days). The detection rate of persister on MODS and indirect absolute concentration were 49.5% and 47.8% respectively,the coincidence rate was 95.5%(kappa value: 0.91),and the detection coincidence has high concordance in different smear samples. The sensitivity and specificity of MODS were 97.7% and 93.3%,and the sensitivity,specificity and coincidence of it on INH,RFP,SM,EMB were 100%,84.5%,89.8%,100%,100%,100%,94.6%,98.0%,96.6%,100%,73.8%,75.0% respectively. The two detections of drug susceptibility had high concordance on RFP and SM,but low on INH and EMB.The results indicated MODS is a kind of detection method on the diagnosis and drug susceptibility with simple operation,low cost,rapid analysis and high sensitivity. So it is suitable for the diagnosis of tuberculosis and management,especially in the developing country and undeveloped district.