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1.
Article in English | WPRIM | ID: wpr-887737

ABSTRACT

Objective@#To evaluate multidrug resistant loop-mediated isothermal amplification (MDR-LAMP) assay for the early diagnosis of multidrug-resistant tuberculosis and to compare the mutation patterns associated with the @*Methods@#MDR-LAMP assay was evaluated using 100 @*Results@#The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of MDR-LAMP were 85.5%, 93.6%, 96.7%, and 74.4% for the detection of resistance to isoniazid and rifampicin, respectively, and 80.5%, 92.3%, 98.6%, and 41.4% for the detection of @*Conclusion@#MDR-LAMP is a rapid and accessible assay for the laboratory identification of rifampicin and isoniazid resistance of


Subject(s)
Antitubercular Agents , Bacterial Proteins/genetics , Catalase/genetics , DNA, Bacterial/analysis , DNA-Directed RNA Polymerases/genetics , Drug Resistance, Multiple, Bacterial/genetics , Isoniazid , Molecular Diagnostic Techniques/methods , Mutation , Mycobacterium tuberculosis/isolation & purification , Nucleic Acid Amplification Techniques/methods , Oxidoreductases/genetics , Phenotype , Rifampin , Whole Genome Sequencing
2.
Article in English | WPRIM | ID: wpr-690649

ABSTRACT

<p><b>OBJECTIVE</b>We determined the genetic diversity of Mycobacterium tuberculosis (MTB) in a remote mountainous area of southwest China and evaluated the resolving ability of single nucleotide polymorphism (SNP) genotyping combined with variable number tandem repeat (VNTR) genotyping for Beijing family strains in association with drug resistance status.</p><p><b>METHODS</b>Three hundred thirty-one MTB strains were isolated from patients living in mountainous regions of southwest China, and 8-loci SNP, VNTR-15 genotyping assays, and drug susceptibility testing of 9 drugs were performed.</p><p><b>RESULTS</b>A total of 183 [55.29% (183/331)] strains were classified into the Beijing family. Of the 183 strains, 111 (60.66%) were defined as modern Beijing strains. The most predominant modern Beijing sub-lineage and ancient Beijing sub-lineage were Bmyc10 [39.34% (72/183)] and Bmyc25 [20.77% (38/183)], respectively. Of the isolates, 19.64% (65/331) were resistant to at least 1 of the 9 anti-TB drugs and 17 [4.98% (17/331)] MTB isolates were multi-drug resistant tuberculosis (MDR-TB). Two hundred sixty-one isolates showed a clustering rate of 14.18% (37/261) and a discriminatory index of 0.9990. The Beijing lineage exhibited a significantly higher prevalence of MDR-TB, as well as resistance to isoniazid (INH), rifampin (RIF), and para-aminosalicylic acid (PAS) when analyzed independently (P = 0.005, P = 0.017, P = 0.014, and P = 0.006 respectively). The Beijing lineage was not associated with genetic clustering or resistance to any drug. In addition, genetic clustering was not associated with drug resistance.</p><p><b>CONCLUSION</b>MTB strains demonstrate high genetic diversity in remote mountainous areas of southwest China. Beijing strains, especially modern Beijing strains, are predominant in remote mountainous area of China. The combination of 8-loci SNPs and VNTR-15 genotyping is a useful tool to study the molecular epidemiology of MTB strains in this area.</p>


Subject(s)
Antitubercular Agents , Pharmacology , China , Epidemiology , Cluster Analysis , Drug Resistance, Bacterial , Genotype , Humans , Mycobacterium tuberculosis , Genetics , Phylogeny , Polymorphism, Single Nucleotide , Tuberculosis , Epidemiology , Microbiology
3.
Article in English | WPRIM | ID: wpr-311402

ABSTRACT

We performed molecular identification of clinical isolates of Mycobacterium fortuitum (M. fortuitum) and conducted drug susceptibility testing to analyze the in vitro susceptibility of clinical M. fortuitum isolates and potential molecular mechanism conferring resistance to fluoroquinolone and macrolide drugs. The results showed that moxifloxacin had the highest in vitro activity against M. fortuitum, and most M. fortuitum isolates were resistant to clarithromycin and linezolid in China. The loss of genetic mutation in clarithromycin- and amikacin-resistant isolates indicates that some other intrinsic mechanism conferring clarithromycin and amikacin resistance plays an essential role in M. fortuitum infection.


Subject(s)
Antitubercular Agents , Pharmacology , China , Drug Resistance, Bacterial , Microbial Sensitivity Tests , Mycobacterium fortuitum
4.
Article in English | WPRIM | ID: wpr-311400

ABSTRACT

China has a double burden of diabetes mellitus and tuberculosis, and many studies have been carried out on the mutual impact of these two diseases. This paper systematically reviewed studies conducted in China covering the mutual impact of epidemics of diabetes and tuberculosis, the impact of diabetes on multi-drug resistant tuberculosis and on the tuberculosis clinical manifestation and treatment outcome, the yields of bi-directional screening, and economic evaluation for tuberculosis screening among diabetes patients.


Subject(s)
China , Epidemiology , Coinfection , Epidemiology , Microbiology , Diabetes Mellitus , Epidemiology , Epidemics , Mass Screening , Economics , Prevalence , Tuberculosis , Epidemiology , Microbiology , Tuberculosis, Multidrug-Resistant , Epidemiology , Microbiology
5.
Article in English | WPRIM | ID: wpr-311384

ABSTRACT

<p><b>OBJECTIVE</b>Mycobacterium avium (M. avium) and Mycobacterium intracellulare (M. intracellulare) are the major causative agents of nontuberculous mycobacteria (NTM)-related pulmonary infections. However, little is known about the differences in drug susceptibility profiles between these two species.</p><p><b>METHODS</b>A total of 393 NTM isolates were collected from Shanghai Pulmonary Disease Hospital. Sequencing of partial genes was performed to identify the strains at species level. The minimum inhibitory concentration (MIC) was used to evaluate the drug susceptibility against 20 antimicrobial agents. Variable number of tandem repeat (VNTR) typing was conducted to genotype these two species.</p><p><b>RESULTS</b>A total of 173 (44.0%) M. avium complex (MAC) isolates were identified, including 41 (10.4%) M. avium isolates and 132 (33.6%) M. intracellulare isolates. Clarithromycin and amikacin were the two most effective agents against MAC isolates. The Hunter-Gaston Discriminatory Index (HGDI) values for VNTR typing of M. avium and M. intracellulare isolates were 0.993 and 0.995, respectively. Levofloxacin resistance was more common among the unclustered strains than among the clustered strains of M. intracellulare.</p><p><b>CONCLUSION</b>M. intracellulare was the most common NTM species in China. Clarithromycin and amikacin had high antimicrobial activities against MAC. VNTR typing of MAC isolates revealed a high discriminatory power. Levofloxacin resistance was associated with unclustered strains of M. intracellulare.</p>


Subject(s)
Anti-Bacterial Agents , Pharmacology , Drug Resistance, Bacterial , Genotype , Humans , Mycobacterium avium Complex , Genetics , Mycobacterium avium-intracellulare Infection , Epidemiology , Microbiology
6.
Article in English | WPRIM | ID: wpr-258848

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the prevalence of primary drug-resistant tuberculosis (TB) and associated risk factors in China. We also explored factors contributing to the transmission of multidrug-resistant tuberculosis (MDR-TB).</p><p><b>METHODS</b>A total of 2794 representative, Mycobacterium tuberculosis isolates from treatment-naive patients were subjected to drug susceptibility testing, and risk factors for drug-resistant TB were analyzed. We also analyzed MDR-TB strain sublineages, drug-resistance-conferring mutations, and risk factors associated with clustered primary MDR strains.</p><p><b>RESULTS</b>Among 2794 Mycobacterium tuberculosis isolates from treatment-naive patients, the prevalence of any resistance to first-line drugs was 33.2% and the prevalence of MDR-TB was 5.7%. We did not find any risk factors significantly associated with resistance to first-line drugs. The 93 primary MDR-TB isolates were classified into six sublineages, of which, 75 (80.6%) isolates were the RD105-deleted Beijing lineage. The largest sublineage included 65 (69.9%) isolates with concurrent deletions of RD105, RD207, and RD181. Twenty-nine (31.2%) primary MDR strains grouped in clusters; MDR isolates in clusters were more likely to have S531L rpoB mutation.</p><p><b>CONCLUSION</b>This study indicates that primary drug-resistant TB and MDR-TB strains are prevalent in China, and multiple measures should be taken to address drug-resistant TB.</p>


Subject(s)
Adolescent , Adult , Aged , Aged, 80 and over , China , Epidemiology , Drug Resistance, Multiple, Bacterial , Genetics , Female , Humans , Male , Middle Aged , Prevalence , Risk Factors , Tuberculosis, Multidrug-Resistant , Epidemiology , Young Adult
7.
Article in English | WPRIM | ID: wpr-258826

ABSTRACT

<p><b>OBJECTIVE</b>To compare the performance of MTBDRplus V2 and Xpert MTB/RIF for detecting smear negative pulmonary tuberculosis (PTB).</p><p><b>METHODS</b>Clinical PTB suspects were enrolled consecutively in Anhui Chest Hospital and Xi'an Chest Hospital from January to December in 2014. The sputum samples of smear negative PTB suspects were collected and decontaminated. The sediment was used to conduct MTBDRplus V2, Xpert MTB/RIF and drug susceptibility test (DST). All the samples with discrepant drug susceptibility result between molecular methods and phenotypic method were confirmed by DNA sequencing.</p><p><b>RESULTS</b>A total of 1973 cases were enrolled in this study. The detection rates of Mycobacterium tuberculosis complex (MTBC) by MTBDRplus V2 and Xpert MTB/RIF were 27.67% and 27.98%, respectively. When setting MGIT culture result as a gold standard, the sensitivity and specificity of MTBDRplus V2 were 86.74% and 93.84%, and the sensitivity and specificity of Xpert MTB/RIF were 86.55% and 93.43%, respectively. For the detection of the resistance to rifampin, the sensitivity and specificity of MTBDRplus V2 were 94.34% and 96.62%, and the sensitivity and specificity of Xpert MTB/RIF were 88.68% and 95.96%, respectively. For the detection of the resistance to isoniazid, the sensitivity and specificity of MTBDRplus V2 were 77.38% and 98.02%, respectively.</p><p><b>CONCLUSION</b>MTBDRplus V2 and Xpert MTB/RIF can be used to detect MTBC in smear negative samples with satisfactory performance.</p>


Subject(s)
Antitubercular Agents , Pharmacology , Bacteriological Techniques , Methods , Drug Resistance, Bacterial , Humans , Isoniazid , Pharmacology , Mycobacterium tuberculosis , Sensitivity and Specificity , Tuberculosis, Pulmonary , Diagnosis , Microbiology
8.
Article in English | WPRIM | ID: wpr-264560

ABSTRACT

In order to evaluate the performance of a molecular Hain line probe assay (Hain LPA) for rapid detection of rifampicin and isoniazid resistance of Mycobacterium tuberculosis in China, 1612 smear positive patients were consecutively enrolled in this study. Smear positive sputum specimens were collected for Hain LPA and conventional drug susceptibility testing (DST). The sensitivity and specificity of Hain LPA were analyzed by using conventional DST as golden reference. The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for rifampicin resistance detection were 88.33%, 97.66%, 81.54%, and 98.62%, respectively. The sensitivity, specificity, PPV and NPV for isoniazid resistance detection were 80.25%, 98.07%, 87.25%, and 96.78%, respectively. These findings suggested that Hain LPA can be an effective method worthy of broader use in China.


Subject(s)
China , Genotyping Techniques , Methods , Humans , Isoniazid , Pharmacology , Mycobacterium tuberculosis , Genetics , Rifampin , Pharmacology , Tuberculosis, Multidrug-Resistant , Diagnosis , Microbiology
9.
Article in English | WPRIM | ID: wpr-264626

ABSTRACT

Sputum transportation from county-level to prefecture-level is an ideal strategy to cover the shortage of the laboratory capability in the resource-poor setting. Here, we firstly evaluated the feasibility of sputum transportation system in China by analyzing the culture and molecular diagnosis results from 1982 smear-positive patients with different delay in processing for culture. In this study, the total contamination rate was 2.32% and the total smear positive/culture negative (S+/C-) rate was 7.57%. We found that sputum specimens refrigerated for no more than 7 d before mycobacterial detection did not affect culture significantly. In addition, the invalid result rates among 0-3 d, 3-7 d, and 7+ d group were 3.63%, 3.14%, and 12.48%, respectively. Statistic analysis revealed that molecular diagnostic results while the invalid result rate of genechip for the specimen with more than 7 d delay was significantly higher (P<0.001). The refrigerators equipped in county laboratories, transport at low temperature and frequent transport services once a week will ensure the feasibility of sputum transportation system in China.


Subject(s)
China , Feasibility Studies , Humans , Mycobacterium , Specimen Handling , Sputum , Microbiology , Transportation
10.
Chinese Journal of Epidemiology ; (12): 168-172, 2013.
Article in Chinese | WPRIM | ID: wpr-327650

ABSTRACT

<p><b>OBJECTIVE</b>To study the tuberculosis clustering areas and the changing trend, from 2008 to 2010, so as to provider the reference for tuberculosis control.</p><p><b>METHODS</b>Global spatial autocorrelation and SaTScan methods were used to detect and analyse the spatial clustering of total tuberculosis notification rate and the new smear-positive pulmonary tuberculosis notification rate, at the provincial level from 2008 to 2010.</p><p><b>RESULTS</b>The spatial clustering (SC) phenomenon was significant on total notification rate and new smear-positive pulmonary tuberculosis notification rate from 2008 to 2010 (P < 0.01). The coverages of clustering areas on total notification rate showed a reduction from 19 provinces to 14 provinces, distributed in the south, west and north-east areas of China. The coverages of clustering areas on new smear-positive pulmonary tuberculosis notification rate concentrated in 14 provinces which covered the south and north-east of China.</p><p><b>CONCLUSION</b>The disease burden and the risk of transmission in the clustering areas of tuberculosis both located in the south and the north-east of China. The disease burden of tuberculosis was high in the west of China, but not the areas with high risk of transmission.</p>


Subject(s)
China , Epidemiology , Cluster Analysis , Humans , Statistical Distributions , Tuberculosis , Epidemiology
11.
Chinese Journal of Epidemiology ; (12): 1167-1170, 2012.
Article in Chinese | WPRIM | ID: wpr-289559

ABSTRACT

Objective To preliminarily understand the genotyping characteristics regarding the variable number tandem repeats (VNTR) of Mycobacterium tuberculosis clinical isolates so as to provide evidence for the development of tuberculosis control and prevention programs in Fujian province.Methods Fifteen VNTR locus sets were used to detect the clinical isolates from the fifth surveillance project on tuberculosis resistance,in Fujian province.BioNumerics version 4.5 were used to analyze the cluster from the results generated by genotyping.Results 313 Mycobacterium tuberculosis isolates were divided into 9 clusters,including Ⅰ,Ⅱ,Ⅲ,Ⅳ,Ⅴ,Ⅵ,Ⅶ,Ⅷ and Ⅸ,with the number of 220,9,48,2,1,3,10,10,10 isolates,respectively.Cluster Ⅰ was the major lineage,accounting for 70.3% (220/313) of the total.Resistance rates of cluster Ⅰ isolates to isoniazid,streptomycin,ethambutol and multi-drug-resistaut were not statistically different from other clusters (P>0.05).However,resistance rate to rifampicin (RFP) was significantly higher than that of other isolates of the clusters,33.2% (73/220) vs.20.4% (19/93) (P<0.05).Conclusion The strains isolated from Fujian province showed significant polymorphism on genotyping.Cluster Ⅰ seemed to be the dominant,calling for the close monitoring program on cluster Ⅰ strains.Results from our initial studies demonstrated the existence of significant correlation between cluster Ⅰ strains and drug resistance to RFP.

12.
Chinese Medical Journal ; (24): 184-187, 2010.
Article in English | WPRIM | ID: wpr-266003

ABSTRACT

<p><b>BACKGROUND</b>An increasing incidence of disease caused by nontuberculous mycobacteria (NTM) is being reported. The purpose of this study was to determine the isolation rates of NTM from various clinical specimens, and their antimicrobial susceptibility patterns, over a 4-year period in Shanghai.</p><p><b>METHODS</b>All NTM isolated between 2005 and 2008 at Shanghai Pulmonary Hospital, a key laboratory of mycobacteria tuberculosis in Shanghai, China, were identified with conventional biochemical tests and 16S rRNA gene sequencing. Antimicrobial susceptibility for all NTM was determined using the BACTEC MGIT 960 system.</p><p><b>RESULTS</b>A total of 21,221 specimens were cultured, of which 4868 (22.94%) grew acid fast bacilli (AFB), and 248 (5.09%) of the AFB were NTM. The prevalence rate of NTM was determined as 4.26%, 4.70%, 4.96% and 6.38% among mycobacteria culture positive samples in years 2005, 2006, 2007 and 2008 respectively. These data indicated that the prevalence rate has continuously increased. Sixteen different species of NTM were identified, the most commonly encountered NTM in Shanghai were M. chelonae (26.7%), followed by M. fortuitum (15.4%), M. kansasii (14.2%), M. avium-intracellulare complex (13.1%) and M. terrae (6.9%). The rare species identified were M. marinum, M. gastri, M. triviale, M. ulcerans, M. smegmatis, M. phlci, M. gordonae, M. szulgai, M. simiae, M. scrofulaceum and M. xenopi. The five most commonly identified NTM species showed high drug resistance to general anti-tuberculosis drugs, particularly, M. chelonae and M. fortuitum appear to be multi-drug resistance.</p><p><b>CONCLUSIONS</b>The prevalence of NTM in Shanghai showed a tendency to increase over the course of the study. The five most commonly isolated NTM species showed high drug resistance to first line anti-tuberculosis drugs.</p>


Subject(s)
Antitubercular Agents , Pharmacology , China , Epidemiology , Drug Resistance, Bacterial , Mycobacterium , Physiology , Mycobacterium Infections , Epidemiology , Microbiology , Mycobacterium chelonae , Physiology , Mycobacterium fortuitum , Physiology , Mycobacterium kansasii , Physiology , Mycobacterium marinum , Physiology , Mycobacterium xenopi , Physiology , Nontuberculous Mycobacteria , Physiology , Prevalence
13.
Article in Chinese | WPRIM | ID: wpr-301678

ABSTRACT

<p><b>OBJECTIVE</b>To investigate the distribution of the Beijing genotypes of Mycobacterium tuberculosis (M. tuberculosis) and the relationships between Beijing genotype strains and drug-resistant phenotypes in China.</p><p><b>METHODS</b>Clinical isolates were collected during a 9-month research period from April to December in 2008 in six geographic regions of China. One isolate that had been biochemically confirmed to be a member of the M. tuberculosis complex was collected from each patient. The demographic data of the patients (eg. sex, age, and history of tuberculosis) as well as the drug resistance patterns and sources of the clinical isolates were collected. Drug susceptibility testing was performed using proportion method. Beijing genotypes of M. tuberculosis were identified by spacer oligonucleotide typing or insertion of IS6110 in the genomic dnaA-dnaN locus.</p><p><b>RESULTS</b>Among the 410 M. tuberculosis clinical isolates, 67.1% (275/410) isolates were Beijing genotypes of M. tuberculosis. Significantly larger proportions of tuberculosis patients were infected with Beijing genotypes in the northeastern regions of China than that of in the central-western regions (chi2 = 20.50, P = 0.000). No significant associations were found either between Beijing genotype strains and patients' age, sex, or treatment history. Multidrug-resistant isolates and rifampin-resistant isolates were more common among Beijing genotype strains than among non-Beijing strains (P = 0.002, P = 0.005).</p><p><b>CONCLUSIONS</b>About two third of the clinical isolates of M. tuberculosis in China are Beijing genotypes. Beijing genotype strains are not correlated with patients' age, sex, treatment history. People living in the northeastern regions of China are more susceptible to Beijing genotypes than those living in the central-western of China. Beijing genotype strains tend to be rifampin-resistant or multidrug-resistant.</p>


Subject(s)
Antitubercular Agents , Pharmacology , China , Genotype , Humans , Mycobacterium tuberculosis , Classification , Genetics , Phenotype , Rifampin , Pharmacology , Tuberculosis , Drug Therapy , Tuberculosis, Multidrug-Resistant , Genetics
14.
International Eye Science ; (12): 433-435, 2005.
Article in Chinese | WPRIM | ID: wpr-641796

ABSTRACT

· AIM: To study the clinical characteristics of metastatic bacterial endophthalmitis.endophthalmitis were retrospectively studied.manifestation was found in 17 cases (77%), iridal purulent nodules in 2 cases and retinal purulent embolism In 3 cases. The total number of leucocytes and neutrophilic granulocytes was elevated markedly, while lymphocyte count was reduced significantly in early stage. Positive rate of bacterial cultivation was 36%.dophthalmitis often have apparent extraocular infected situation before eye Is involved. Ocular appearance and laboratory examination have some specificity in early stage, while bacterial cultivation, as a golden standard,needs to be further improved.

15.
Article in Chinese | WPRIM | ID: wpr-278866

ABSTRACT

Hematopoiesis undergoes several migrations from yolk sac to liver and spleen, and finally bone marrow until the end of life. A number of investigations have demonstrated that the hematopoietic microenvironment plays very important role in this process. However, the exact mechanisms remain unknown. In order to systematically analyze and understand the role of hematopoietic microenvironment in the regulation and control of hematopoiesis, a microarray containing 588 complementary DNAs was used to compare the gene expressions between those in murine fetal liver and bone marrow cells. The results obtained from array hybridization were analyzed and reconfirmed by using bioinformatics and RT-PCR as well as Northern blot. The results showed that 65 and 131 genes were relatively high expressed in bone marrow and fetal liver cells respectively among 588 known genes in the array-membrane. According to the survey in the PubMed, 39 out of bone-marrow-expressed genes and 71 in fetal-liver-expressed genes were closely related to the hematopoiesis. Further reconfirmation by RT-PCR or Northern blot has demonstrated that CD18, CD44 an d PSGL-1 genes chosen for analysis were highly expressed in adult bone marrow, but unexpressed or lower expressed in fetal liver cells, resulting in high similarity to the array results. Moreover, the expressions of CD18 and CD44 in fetal liver were down-regulated with the increment of gestational age. In conclusion, the gene expressions in bone marrow and fetal liver cells are obviously different, some of the genes are down-regulated at the different stages of ontogeny. The different gene expression levels between bone marrow and fetal liver, especially those genes closely related to the hematopoiesis, may be the molecular basis for the explanation of why hematopoietic stem cells derived from different tissues have different characterizations as well as the differences from the beginning and terminating of fetal liver hematopoiesis, and why hematopoietic stem cells derived from fetal liver is tremendously difficult to be grafted in bone marrow.


Subject(s)
Animals , Bone Marrow , Metabolism , Female , Fetus , Metabolism , Gene Expression Profiling , Hematopoiesis , Hepatocytes , Metabolism , Male , Mice , Oligonucleotide Array Sequence Analysis
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