| objectiveTo observe the drug resistance of tuberculosis in patients in bozhou city Anhui China,and the mutagenesis of related genes in the resistant strains of isoniazid and rifampicin.To analyze the specificity and sensitivity of line probe assay(LPA)in detection of tuberculosis(TB)drug resistant,and provide scientific evidence for the control of tuberculosis epidemic.MethodsSputum specimens were cultured in vitro and drug sensitivity test was conducted by proportion method.The drug resistance test results of 6 kinds of drugs were analyzed,including rifampicin(RFP),isoniazid(INH),streptomycin(SM),ethambutol(EMB),ofloxacin(OFX)and kanamycin(KAM),and drug resistance rate in different group were compared by?~2 test.Extracted DNA and the target genes were amplified to analyze the mutation of INH and RFP resistant genes.Sensitivity and specificity of LPA in the rapid diagnosis of multi-drug resistant tuberculosis(MDR-TB)was caculated.Results1.Epidemiological characteristics of tuberculosis patientsThis study included 251 patients,208 males(82.87%)and 43 females(17.13%)?Initial treatment was performed in 212 patients and retreatment in 39 patients.The oldest was 91 years old,the youngest patient was 15 years old,and the average age was 52.64years old.The age of patients was mainly distributed in middle age and old age.The occupation was mainly farmer,about 232 cases(92.43%).The number of patients whose annual income was less than 20,000 yuan accounts for 64.14%.Poor education lower than junior middle school was majorityabout 231 cases(92.03%)?2.Culture and drug resistance of mycobacterium tuberculosisTotal 266 sputum samples were detected.251 strains were Mycobacterium tuberculosis(MTB),accounting for 94.36%,and 15 strains were Non-tuberculosis Mycobacteria(NTM),accounting for 5.64%.Therefor,251 cases were included.Among the 251 patient,212 cases were initially treated and 39 cases were retreated patients.178patients were sensitive to all 6 drugs,accounting for 70.92%,and 73 patients were resistant to at least one drug.The drug sensitive test shows 73 strains were drug resistant(29.08%),the highest drug-resistant proportions was RFP(16.33%),The order was RFP>INH=SM>OFX>EMB>KAM.The total drug resistance rate of first-line drugs was 27.89%and second-line drugs was 8.37%.The MDR were detected in 31cases(12.35%),and extensive drug resistant tuberculosis(XDR)strains in 3 cases.3.Comparison of drug sensitivity tests between new case and re-treated caseThe results showed that the drug-resistant proportions was 25.94%in new case group,the highest drug-resistant proportions was SM(15.09%).The drug-resistant proportions was 46.15%in re-treated case group,and the highest drug-resistant proportions was RFP(43.59%).The drug-resistant proportions of first-line and second-line drugs in re-treated case group were higher than that in new case group.The drug-resistant proportions of MDR in re-treated case group was significantly more than that in new case group,and the drug-resistant proportions of INH?RFP?OFX in re-treated case group was higher than that in new case group.4.Performance comparison between L-J and LPATake the result of L-J as gold standard,46 samples of RFP or INH resistant strains were detected by LPA.In RFP resistant group,The resuts of LAP showed the sensitivity for drug resistance detection was 97.5%,the specificity was 83.33%and consistency was 0.808.In INH resistant group,The sensitivity of LAP for drug resistance detection was 88.89%,specificity was 90%,and consistency was 0.712.MDR-TB detection had a sensitivity of 83.33%,specificity of 87.50%and consistency of 0.679.The detection of MDR-TB by LPA and L-J had no statistic significant difference(?~2=0.73,P>0.05).5.Condition of genetic mutationOf the 40 rifampicin-resistant strains,the locus of rpoB gene mutation was mainly S531L,with 27 cases(67.5%).The mutation of 33 isoniazid resistant strains was mainly the S315T1 site of KatG gene in 22 cases(66.7%).All the 7 cases of inhA gene mutation were C15T site,and 3 cases of S315T1 site were also changed at the same time.ConclusionThe drug resistance of tuberculosis patients was not optimistic in bozhou.Multi-drug resistant(MDR)in re-treated case group was very serious.The mutation of the resistant gene of RFP and INH was basically consistent with the research in some parts of China,but it still had its own special characteristics.The LPA had high sensitivity and specificity for the drug resistance detection of RFP and INH,whichwill be benefit for clinical application. |
PDF Full Text Request