ABSTRACT
Objective To understand the recent transmission of Mycobacterium tuberculosis (MTB),and to identify the influencing factors of recent transmission among pulmonary tuberculosis (TB) patients in Jing'an district,Shanghai.Methods The genotypes and drug resistances of MTB isolated from TB patients registered in the TB designated hospitals in Jing'an district during 2010-2015 were analyzed through 12-loci Mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR)(QUB1 lb,QUB18,Mtub21,Mira26,QUB26,Mtub04,Miru31,Miru40,VNTR2372,VNTR3820,3232,4120),and tested for drug susceptibility as well.With the results of field epidemiological investigation,univariate and multivariate analyses were performed to analyze the distribution of the clusters and influencing factors on recent transmission.Results This study enrolled 80 TB patients,23 (28.75％) had a resistance to at least one anti-TB drug,and the prevalence of multidrug-resistant tuberculosis (MDR-TB) was 16.25％.A total of 65 genotypes were identified with 58 (72.50％,58/80) being unique and 7 clusters with 2-10 isolated in each cluster.The proportion of clustering was 27.50％ (22/80).Results from the multivariate analysis revealed that multidrug-resistance (OR=35.799,95％CI:4.239-302.346) and having comorbidity with TB (0R=7.695,95％CI:1.421-41.658) were independently associated with the clustering,which suggesting a recent transmission.The field investigation to the clustered cases proved that the patients in two clusters had epidemiological links,one was between family members,and the other contained 10 MDR-TB patients with 9 knowing each other which have a definite connection and 1 having the possible connection with them.Conclusion Recent transmission of tuberculosis happened among TB patients in Jing'an district,with high risks among the MDR-TB patients.
ABSTRACT
Objective To understand the recent transmission of Mycobacterium tuberculosis (MTB),and to identify the influencing factors of recent transmission among pulmonary tuberculosis (TB) patients in Jing'an district,Shanghai.Methods The genotypes and drug resistances of MTB isolated from TB patients registered in the TB designated hospitals in Jing'an district during 2010-2015 were analyzed through 12-loci Mycobacterial interspersed repetitive unit-variable number tandem repeat (MIRU-VNTR)(QUB1 lb,QUB18,Mtub21,Mira26,QUB26,Mtub04,Miru31,Miru40,VNTR2372,VNTR3820,3232,4120),and tested for drug susceptibility as well.With the results of field epidemiological investigation,univariate and multivariate analyses were performed to analyze the distribution of the clusters and influencing factors on recent transmission.Results This study enrolled 80 TB patients,23 (28.75％) had a resistance to at least one anti-TB drug,and the prevalence of multidrug-resistant tuberculosis (MDR-TB) was 16.25％.A total of 65 genotypes were identified with 58 (72.50％,58/80) being unique and 7 clusters with 2-10 isolated in each cluster.The proportion of clustering was 27.50％ (22/80).Results from the multivariate analysis revealed that multidrug-resistance (OR=35.799,95％CI:4.239-302.346) and having comorbidity with TB (0R=7.695,95％CI:1.421-41.658) were independently associated with the clustering,which suggesting a recent transmission.The field investigation to the clustered cases proved that the patients in two clusters had epidemiological links,one was between family members,and the other contained 10 MDR-TB patients with 9 knowing each other which have a definite connection and 1 having the possible connection with them.Conclusion Recent transmission of tuberculosis happened among TB patients in Jing'an district,with high risks among the MDR-TB patients.
ABSTRACT
Objective To investigate the prevalence and risk factor of Ofloxacin resistance among the tuberculosis patients in Shanghai.Methods Totally 447 isolates resistant to anyone of first-line drug (Isoniazid,Rifampicin,Streptomycin and Ethambutol) and 151 randomly selected isolates susceptible to all above drugs were collected from district tuberculosis(TB) hospitals in Shanghai during 2009 to 2010.All 598 isolates were subject to Ofloxacin sensitive test.Logistic regression analysis was conducted to determine risk factors of Ofloxacin resistance.DNA sequencing was applied to study the mutation characteristics in gyrA and gyrB among Ofloxacin resistant isolates.Results Seventy-two(16.1%) of the 447 drug-resistant isolates were found resistant to Ofloxacin,and the Ofloxacin resistant rate among multiple drug-resistant (MDR) isolates was 39.6%(44/111).Ofloxacin resistance was also found in 4(2.6%) of the 151 drug sensitive isolates.Logistic regression analysis showed that first-line drug-resistance MDR(resistant to at least rifampin and isoniazid) and poly-drug resistance(resistance to two or more first-line drugs but not MDR) had significant effect on Ofloxacin resistance(OR = 19.5、5.6,95% CI:6.4 - 59.4、1.7 - 18.1,all P＜ 0.05);re-treatment(OR = 2.3,95 % CI:1.2 -4.0,P＜ 0.05),and a higher age(OR = 1.03,95 % CI:1.0 1 - 1.05,P＜ 0.05)were also significantly associated with Ofloxacin resistance.Resistance mutations in the gyrA and gyrB genes were detected in 62 of 76(81.6%) isolates with phenotypic Ofloxacin-resistance. Conclusions The Ofloxacin resistance rate in Shanghai MDR-TB patients is significantly higher than the pan-susceptible TB patients.Risk factors of ofloxacin resistance are MDR,poly-resistant,retreated patients,age.Among them,MDR has the highest strength of association.