ABSTRACT
Objective To determine the genotype and clustering characteristics of multidrug-resistant (MDR) mycobacterium tuberculosis in Wuhan City. Methods A total of 149 mycobacterium tuberculosis strains from MDR tuberculosis (MDR-TB) patients were genotyped by DTM-PCR, mycobacterial interspersed repetitive unit–variable number tandem repeat typing (MIRU-VNTR) and sequencing of drug-resistant associated genes. The Hunter-Gaston discriminatory index (HGDI), clustering rate and recent minimum estimated infection rate were calculated. Results The cumulative HGDI of all MIRU loci was 0.9944. Gene locus with the highest HGDI（0.6467）was QUB11b. Combing MIRU-VNTR and DTM-PCR, 111 unique genotypes and 11 clustered genotypes（38 strains）from 149 isolates were identified. The clustering rate was 25.50%, and the recent minimum infection rate was estimated to be 18.12%. After further genotyping by sequencing of drug-resistant associated genes, the results showed that 17 (44.74%) strains in each cluster shared the same mutation sites, while the other strains had different mutation sites. Conclusion The combination of DTM-PCR, 24 locus MIRU-VNTR typing and drug resistance gene sequencing demonstrates a relatively high discriminatory power, which is suitable for the genotyping of multi drug resistant mycobacterium tuberculosis in Wuhan. The epidemic of MDR-TB in Wuhan is mainly caused by reactivation, and the recent transmission rate is not high.
ABSTRACT
Objective@#To investigate the survival time of multidrug-resistant tuberculosis (MDR-TB) patients and the influential factors in Wuhan.@*Methods@#The relevant information were collected from TB management information system, cause of death reporting system and medical records by trained doctors. The univariate and multivariate Cox proportional hazards model were applied to analyze the factors affecting survival time of patients.@*Results@#A total of 552 patients with MDR-TB were included in the analysis. After the diagnosis of MDR-TB, the cumulative survival rates from the first year to the third year were 0.94, 0.88, and 0.80, respectively. The mortality density of MDR-TB patients was 6.52/100 person-years, and the median survival time was (89.52±1.85) months. Kaplan-Meier analysis showed that the cumulative survival rate of the standardized treatment group was significantly higher than that of the non-standardized treatment group (Log rank=101.070, P<0.001). Compared with the patients aged <30 years, the HR of the patients aged 30-years and ≥60 years were 2.987 (95%CI: 1.268-7.036), 4.957 (95%CI: 1.942-12.653). Compared with the patients with the education level of high school and above, the HR of the patients with education level of junior high school/primary school and below were 1.908 (95%CI: 1.152-3.160), 1.681(95%CI: 1.033-2.735). Compared with the patients without diabetes, the HR of the patients with diabetes was 1.961(95%CI: 1.347-2.854). Compared with the patients without other serious diseases, the HR of the patients with other serious diseases was 2.597 (95%CI: 1.820-3.706). Compared with the patients who had been treated less than one time, the HR of the patients having previous treatment with more than 2 times was 1.611 (95%CI: 1.077-2.409). Compared with patients receiving standard MDR regimen treatment, the HR of the patients receiving no standard MDR regimen treatment was 3.155 (95%CI: 2.132-4.670).@*Conclusions@#The cumulative survival rate of MDR-TB patients without standard treatment was significantly lower than that of patients with standard treatment. Older age, low educational level, diabetes mellitus, other serious diseases, more than two times treatment in the past, and receiving no multi-drug resistance regimen treatment were the risk factors affecting the survival of MDR-TB patients.
ABSTRACT
Objective To analyze the clinical characteristics and therapy of levofloxacin-induced prolonged Q-T interval in patients with multi-drug resistant tuberculosis ( MDR-TB) . Methods Clinical materials of 6 patients with MDR-TB who developed prolonged Q-T/QTc interval caused by levofloxacin therapy were analyzed. Those cases were collected from the Tuberculosis Prevention and Control of Wuhan City form April 2010 to August 2014. Results The proportion of patients with levofloxacin-induced prolonged Q-T interval was approximately 3.0%.The condition occurred 2-8 months after the administration. The initial value of QTc interval ranged from 397 ms to 439 ms, while the average was (410.17±14.62) ms.The value of QTc interval was extended to 470-486 ms after treatment of levofloxacin, while the average was (476.33±6.16) ms.The increase of QTc interval was 47-85 ms, while the average was ( 66 ± 11. 48 ) ms. None of them developed Tdp. Conclusion The application of high dosage and long treatment course of levofloxacin in patients with MDR-TB could result in the extension of the Q-T/QTc interval, which should arouse our serious attention. In order to detect the abnormal Q-T/QTc interval in early stage, electrolyte level examination as well as ECG examination should be considered as routine tests before initiation of treatment and during the follow-up treatment.