| Objective Analyze the detection effect of drug-resistant tuberculosis(TB)under different screening modes in different periods in Jiaxing city from 2015 to 2020.To study the differential protein expression of extensively drug-resistant Mycobacterium tuberculosis(XDR-TB)by proteomics,analyze the possible drug resistance mechanism,and provide a basis for the prevention and control of drug-resistant tuberculosis in our city.Methods 1)The TB management information and TB laboratory test results registered in Jiaxing during the Global Fund project period from 2015 to 2017 and the Middle Gate TB project period from 2018 to 2020 were selected to obtain the annual TB pathogen detection,drug resistance screening,screening methods,the number of confirmed drug resistance and the time required for drug sensitivity diagnosis during the study period.The drug resistance detection performance of different screening modalities was analyzed.2)At the same time,the consistency of phenotypic drug susceptibility and molecular detection results of tuberculosis was compared,and the reasons for the inconsistency were analyzed.3)To analyze the differential protein expression between XDR strains and standard H37RV strains by proteomic analysis.Results 1)Comparison of the positive detection rate of pathogens,drug resistance screening rate,total drug resistance rate and rifampin resistance rate under different screening modes in different periods of Jiaxing city from 2015 to 2020.Under the screening mode during the China Cover project period(2018-2020),The positive rate of pathogens was 55.96%(2400/4289),which was higher than that of 44.58%(2297/5153)during the Global Fund period(2015-2017)(χ2=121.281,p<0.05).The screening rate of drug resistance(90.25%vs63.69%)was higher in the period of China CAP program than that in the period of Global Fund,and the difference was statistically significant(2=471.230,p<0.05).Compared with the total drug resistance rate,the drug resistance rate of tuberculosis during the China CAP project period(6.05%,131/2166)was lower than that during the Global Fund period(18.66%,273/1463)(2=140.399,p<0.05).The rifampicin resistance rate 3.55%(77/2166)was also lower than that of the global Fund period 5.47%(80/1463),and the differences were statistically significant(2=7.723,p<0.05).During the project period,107 initial drug resistance patients and 24 retreatment patients were detected,and the number of initial drug resistance patients was 4.46 times that of retreatment patients.Comparing the use of molecular and phenotypic drug susceptibility testing methods under different screening modes,the utilization rate of molecular testing methods was 89.80%in the period of China CAP Project,which was significantly higher than 7.59%in the period of Global Fund(2=2403.168,p<0.05).The average time for diagnosis of rifampicin-resistant TB was 2.4 days by rapid molecular detection,which was significantly shorter than 35.2 days by traditional phenotypic drug resistance detection(Z=-41.206,p<0.05).In terms of testing cost,the molecular detection methods selected during the China Cover Project period were more expensive than the traditional detection during the Global Fund period(501vs144 yuan/case).2)Comparison of the results of molecular drug resistance test and phenotypic drug sensitivity test:the consistency rate of rifampicin(RFP)resistance test was 96.62%(1478 cases of sensitive,64 cases of resistant),and the inconsistency rate was 3.38%;The consistent rate of isoniazid(INH)was 95.24%(1465 sensitive cases and 55 resistant cases),and the inconsistent rate was 4.76%.The reasons for the inconsistent results of the two tests were analyzed:inconsistent test samples,detection technology limitations,different mutation types,silent mutations,heterogeneous drug resistance and other drug resistance mechanisms.3)Using 2-DE and iTRAQ proteomics,a total of 212 differentially expressed proteins with consistent changes were identified in the 2 clinical XDR resistant strains,with H37Rv as the control.Seven proteins related to drug targets were found,including 2 up-regulated proteins(Rv2245,Rv3423c proteins)and 5 down-regulated proteins(Rv1484,Rv0667,Rv3794,Rv3795,Rv2981c proteins).There were 4 proteins related to cell wall signaling pathway synthesis,Rv2682c,Rv3582c and Rv3423c proteins were up-regulated,and Rv2981c protein was down-regulated.These up-regulated or down-regulated proteins were partially related to the molecular mechanism of drug resistance.The B cell,CTL cell and TH cell epitopes of Rv2682c protein were predicted and verified at the protein expression level.Conclusion 1)The positive detection rate of pulmonary tuberculosis pathogens and the drug resistance screening rate in Jiaxing City from 2015 to 2020 showed an overall upward trend,while the total drug resistance rate and rifampicin resistance rate showed an overall downward trend.Different drug resistance screening strategies have their own characteristics.It is appropriate to optimize the process and expand the screening strategy,not only for high-risk groups,but also for all smear-positive patients.2)Gene Xpert MTB/RIF assay combined with phenotypic drug susceptibility testing is a suitable screening technique.3)Analysis of differential protein expression by proteomics technology is worthy of further exploration for the mechanism of XDR. |
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