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Objective To identify drug resistance status of Mycobacterium tuberculosis (MTB) strains by the GenoType MTBDRplus line-probe assay (LPA),compare its performance with traditional drug susceptibility testing (DST),and to assess its predictive value for the prognosis of patients with drug resistance tuberculosis.Methods Pulmonary tuberculosis patients who visited Zhuji People's Hospital,Zhejiang Province during February 2011 and January 2012 with a positive result of sputum smear at baseline were all recruited.A total of 275 culture positive specimens were collected,then isolated and cultured for Mycobacterium tuberculosis in the laboratory.DST were performed,meanwhile,GenoType MTBDRplus were also applied to detect resistance to isoniazid (INH) and rifampin (RMP).All the tuberculosis patients who were recruited were followed,including sputum culture and chest radiography.Results There were 192 strains showing drug resistance both by DST and MTBDRplus LPA.Fourteen multidrug resistant (MDR),21 INH mono-resistant and 2 RMP mono-resistant strains were detected by DST.As for GenoType MTBDRplus LPA,MDR,INH mono-resistant and RMP mono-resistant strains were 14,18 and 2,respectively.Taken DST as the gold standard,LPA was more accurate in the detection of resistance to RMP,while it failed to detect 23.8% (5/21) of the INH-resistant strains.We analyzed the prognosis of patients with drug resistance by GenoType MTBDRplus LPA,the rates of treatment success were 84 % (110/131),9/15,3/11 in patients infected with susceptible,INH mono-resistant and MDR strains,respectively.For the 2 cases of RMP mono-resistanee,one was cured and the other failed.The predictive value of molecular drug resistance test for treatment failure in INH mono-resistant patients was 40.0 %,while that was 83.5 % for treatment success in INH susceptible patients.The predictive value for treatment failure in RMP mono-resistant patients was 50.0%,while that was 81.5% for treatment success in RMP susceptible patients.The predictive value for treatment failure in MDR patients was 72.7%,while that was 81.1% for treatment success in patients without MDR.Conclusion The GenoType MTBDRplus LPA assay is a rapid and reliable diagnostic test for resistance of MTB,which can be used to predict the prognosis of drug resistant tuberculosis in the clinical practice.
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Objective To compare the efficacy of add-on adefovir dipivoxil (ADV) therapy and switch-to entecavir (ETV) monotherapy in chronic hepatitis B (CHB) patients with suboptimal response to lamivudine (LAM).Methods A prospective study was performed in 120 CHB patients from Zhuji People' s Hospital and the First Affiliated Hospital of Zhejiang University School of Medicine during June 2010 and June 2011.All patients previously received more than 24 weeks LAM treatment,but HBV DNA was still positive.Patients were randomized assigned to two groups:60 patients received add-on ADV therapy and another 60 switched to ETV monotherapy.Both groups were treated for 48 weeks.Liver and kidney function,alpha-fetal protein (AFP),HBV serum markers,HBV DNA and prothrombin time (PT) were examined,and ultrasonography or CT scan of liver was performed every 1-3 months.x2 test was used to compare the HBV DNA negative rates,HBeAg seroconversion rates,resistance rates and adverse reaction at week 48 between two groups.Results Thirty-three out of 38 patients (86.8%) with baseline HBV DNA 103-105 copies/mL became HBV DNA negative after add-on ADV treatment for 48 weeks,twenty-seven out of 39 patients (69.2%) with baseline HBV DNA 103-105 copies/ml became HBV DNA negative after switch-to ETV treatment.There was a statistical difference between two groups (x2 =4.578,P < 0.05).Sixteen out of 22 patients (72.7%) with baseline HBV DNA > 105 copies/mL became HBV DNA negative after add-on ADV treatment for 48 weeks,while only 52.4% (11/21) patients achieved HBV DNA negative in the switch-to ETV group.There was also a statistical difference between two groups (x2 =4.865,P <0.05).None of patients in add-on group developed virological breakthrough and resistance,while 5 patients in switch-to ETV group developed virogical breakthrough and 3 patients developed genetic mutation.Among them,rtM204V + rtL180M + rtS202G mutation was detected in 2 patients,and rtM204V + rtL180M +rtT184A mutation was detected in 1 patient; all mutations happened in the baseline HBV DNA > 105 copies/mL group.Conclusion The add-on ADV therapy is better in viral inhibition than switch-to ETV therapy for CHB patients with suboptimal response to LAM,and it can reduce the occurrence of drug resistance.