Associations of Mycobacterium tuberculosis genotypes with different ethnic and migratory populations in Taiwan

The distribution of human Mycobacterium tuberculosis (MTB) genotypes is reportedly associated with geography, ethnicity and population migrations. Three groups of 208 patients with tuberculosis in Taiwan were sampled to test this observation: (1) 41 aborigines of Austronesian ethnicity, who have been inhabiting in Taiwan for more than 500 years; (2) 58 veterans of Han Chinese origin, who moved as the first generation from Mainland China to Taiwan 55-60 years ago; and (3) 109 patients representing the general Taiwanese population of Han Chinese whose ancestors migrated to Taiwan around 200-400 years ago. A total of 208 MTB isolates, one per patient, were analyzed by spoligotyping and mycobacterial interspersed repetitive unit (MIRU) typing. Beijing ancient strains and Haarlem strains predominated among aborigines, while Beijing modern strains were common among veterans and the general population. All Beijing strains were further analyzed by typing the NTF loci and RD deletion. Results suggest a chronological trend among Beijing isolates from the three groups: isolates from the aborigines had signatures compatible with ancient lineages, and those from veterans and the general population were more contemporary. Our data indicate that the distribution of MTB genotypes/strains in Taiwan is associated with different populations whose migratory activities occurred between 55 and 500 years ago. These results suggest that transmission of MTB may have been relatively restricted to close contacts.     

Hepatitis C virus genotypes in southern Taiwan: prevalence and clinical implications

The role of hepatitis C virus (HCV) genotypes in the development of hepatocellular carcinoma (HCC) is still controversial. To determine the distribution and clinical implications of HCV genotypes in southern Taiwan, we analysed 418 patients with chronic HCV infections. HCV genotypes were determined using an HCV Line Probe Assay. The predominant HCV genotype was 1b (45.5%), followed by 2a/2c (30.9%) and 2b (6.9%). The prevalence of genotype 1b in HCC patients (60.3%) was significantly higher than in those with liver cirrhosis (38.7%) and chronic hepatitis (38.7%) (P=0.003 and P<0.001, respectively). Patients with chronic HCV 2a/2c infection had higher alanine aminotransferase (ALT) levels than those with chronic HCV 1b infection (P<0.001). Univariate analysis revealed that disease severity was significantly correlated with older age, genotype 1b, lower ALT levels and lower viral load. Based on multiple logistic regression analysis, after adjusting for age and serum HCV RNA levels, HCV 1b infection was still a significant risk factor for HCC. In conclusion, the predominant genotypes in southern Taiwan were 1b and 2a/2c, and disease severity was associated with genotype 1b.     

Factors associated with genotype clustering of Mycobacterium tuberculosis isolates in an ethnically diverse region of southern California,United States

Mycobacterium tuberculosis (Mtb) isolates with identical genotypes, found in different patients, are most likely the result of recent transmission. Mtb strains with closely related genotypes, called clonal complexes, are most likely derived from one another. We examined Mtb genotypes from southern California TB patients from 2005 through 2008 to complete the first comprehensive molecular epidemiology analysis of this complicated and ethnically diverse region. Mtb genotypes were characterized with spoligotype and MIRU-12 typing. MIRU-VNTRplus was utilized to assign genotypes to global lineages and complete cluster analyses. Associations between patient characteristics and genotype clustering and clonal complexes were evaluated using logistic regression and frequency analysis. Of 832 Mtb isolates analyzed, 480 (58%) fell into 94 strain clusters. The majority of isolates were identified as being in the EA1 (31%), LAM (17%) and Haarlem (15%) lineages, but 13 different lineages were found in this region. TB patients with clustered isolates were more likely to be homeless (AOR 3.44, 95% CI 1.65, 7.18) and male (AOR 1.57, 95% CI 1.17, 2.10). Of the 480 clustered strains, 388 aggregated into six clonal complexes.Over 45% of reported TB cases were clustered and likely resulted from recent transmission events. Patients with clustered Mtb isolates that were grouped into clonal complexes had unique socio-demographic characteristics. These data suggest that TB is being transmitted in relatively insular community networks defined by race/ethnicity and country of origin. The addition of clonal complex analysis to simple cluster analysis provides important public health insights into the local transmission of TB in ethnically diverse regions with diverse Mtb genotypes.     

Genotypes and genetic characters of Mycobacterium tuberculosis from Myanmar using three typing methods

Knowledge on basic characteristics of Mycobacterium tuberculosis (MTB) is helpful to understand the disease epidemiology and support the prediction of clinical outcome of the disease. The aim of this study was to detect the genotypes and genotypic characters of clinical Mycobacterium tuberculosis (MTB) isolates from new and retreatment rifampicin-resistant patients using three different genotyping methods. Mycobacterial interspersed repetitive units-variable number tandem repeat (MIRU-VNTR) typing was used to determine the diversity of 222 clinical isolates. Spoligotyping and IS6110-restriction fragment length polymorphism (RFLP) typing were also used to investigate the genetic characters of 105 MTB strains. Among the 15 genotypes detected by MIRU-VNTR, Beijing strains were the most prevalent of all strains (54.8%); new cases (40.5%) and retreatment cases (69.4%), followed by EAI strain. Spoligotyping categorized the strains into 11 lineages and 13 orphans whereas 96 different IS6110 patterns were identified using RFLP method. The mode number of IS6110 was 18 and 20. Higher band numbers were found in Beijing genotype (p < 0.001). Clustering rates by spoligotyping, MIRU-VNTR and IS6110-RFLP typing were 0.714, 0.004 and 0.085, respectively. Discriminatory powers of spoligotyping, MIRU-VNTR typing and IS6110-RFLP typing were 0.637, 1.000 and 0.997, respectively. Dominant Beijing genotype in both new and retreatment cases denoting that prevailing tuberculosis in Myanmar changed from EAI to Beijing lineage.     

70株浙江省结核分枝杆菌临床分离株Spoligotyping基因分型研究

目的了解结核分枝杆菌临床分离株相关基因型的分布情况，并分析北京家族菌株与耐药的相关性。方法收集浙江省结核分枝杆菌临床分离株，常规罗氏培养基培养，应用Spoligotyping进行基因分型研究，聚类分析采用BioNumerics软件，统计学分析采用卡方检验。结果70株浙江省结核分枝杆菌临床分离株可分为2个基因群，即北京家族（Beijing family）和非北京家族（Non-Beijing family），分别占70％（49／70）和30％（21／70），18种基因型，其中12株为独特类型，剩余58株分为6簇。北京家族菌株中，89．8％（44／49）为典型北京家族（typical Beijing family），非北京家族菌株表现为高度的基因多态性，可分为13个基因型，9株为独特的基因型。北京家族菌株中表现为全敏感者71．4％（35／49），表现为耐药者为28．6％（14／49）；而非北京家族菌株中表现为全敏感者为66．7％，表现为耐药者为33．3％，经卡方检验，两者问的差异无统计学意义（X^2=0．158，P〉0．05）。结论北京家族菌株为浙江的流行优势菌株。北京基因犁与耐药无明显相关性。     

宁波市90株结核分枝杆菌临床分离株MLVA基因分型研究

目的研究宁波市结核分枝杆菌的可变数目串联重复序列(VNTR)的分型及分布特征。方法随机选取宁波市结核分枝杆菌临床分离株,常规培养,提取菌体基因组DNA,通过聚合酶链反应(PCR)对15个VNTR位点进行检测,采用BioNumerics软件进行基因分型的聚类分析。结果 90株结核分枝杆菌临床分离株的VNTR位点检测结果显示出明显的基因多态性,基因分型经聚类分析,分为4个基因群(Ⅰ群、Ⅱ群、Ⅲ群、Ⅳ群),84个基因型。Ⅰ群占11.1%,含有10个基因型,Ⅱ群占17.8%,含15个基因型,Ⅲ群占65.6%,含54个基因型,Ⅳ群占5.6%,含5个基因型。结论宁波市结核分枝杆菌VNTRs基因存在明显多态性得到初步证实,至少存在4个VNTR型,主要流行型为Ⅲ型。     

天津市北京基因型结核分枝杆菌流行特征及与耐药表型关系研究

目的 了解北京基因型结核分枝杆菌在天津市人群中的分布、流行特征及其与耐药表型的关系.方法 收集2008年1月至2009年6月天津市结核病控制中心和10个区(县)结核病防治机构肺结核患者中初次分离培养的结核分枝杆菌656株及患者管理信息、临床信息和实验室信息.菌株对利福平、异烟肼、链霉素和乙胺丁醇的药物敏感性试验采用比例...     

多位点可变串联重复序列技术用于西藏地区结核分枝杆菌基因分型的初步研究

目的初步探讨多位点数目可变串联重复序列(MLVA)技术在西藏地区结核分枝杆菌基因分型中的应用和初步了解西藏地区结核分枝杆菌数目可变串联重复序列(VNTR)基因型种类及其分布。方法在拉萨、山南、林芝、日喀则、那曲、昌都6个地区结核病防治中心收集结核分枝杆菌临床分离菌株,设计引物,采用PCR和琼脂糖凝胶电泳技术对结核分枝杆菌20个VNTR位点进行检测,并通过BioNumerics 4.5软件进行DNA指纹图谱多态性分析。结果共收集到217株结核分枝杆菌,分为19个不同的VNTR基因型,其中以Ⅺ型为主要基因型占87.6%(属于北京家族),其次Ⅵ型、ⅩⅤ型、ⅩⅥ型各占1.38%,Ⅰ型、Ⅶ型、ⅩⅢ型各占0.92%,12株结核分枝杆菌为单一的基因型。不同地区之间,以Ⅺ型为主要基因型,分别占各地区的86.8%、91.3%、78.95%、88.2%、95.05、89.3%。结论西藏地区的结核分枝杆菌存在明显的基因多态性,主要流行型为VNTRⅪ型(即北京家族基因型),初步研究结果显示北京家族基因型与卡介苗接种和耐药性无相关性。MLVA分型方法简单、快速,可以有效地用于结核分枝杆菌的基因分型和病原监测。     

厦门市临床分离的466株结核分枝杆菌基因分型研究

目的 了解厦门市结核分枝杆菌基因类型分布及主要流行基因群情况,并建立分型数据库。方法 采用实时荧光PCR法对厦门市2013 - 2015年分离到的466株结核分枝杆菌临床分离株进行菌株确认,然后采用间隔区寡核苷酸分型方法（spoligotyping）对其进行基因分型。分型结果与SpolDB4数据库进行比对,并使用Bionumeric6.6.4软件进行基因聚类分析。结果 466株菌均为结核分枝杆菌,基因分型分成96种基因型别,62种数据库中有相应的SIT编号,34种为新的型别。97.64%(455/466)的菌构成了15个基因簇。466株菌属于7个基因家族及未定义家族,排在前三的分别为:Beijing（北京）家族60.09%（280/466）、T家族21.03%(98/466)、H家族5.58%(26/466)。结论 厦门市结核分枝杆菌基因型别呈现多样性,北京家族为主要的流行基因群。     

Discordant results between genotypic and phenotypic assays (Xpert MTB/RIF vs. BACTEC MGIT 960 system) for detection of RIF-resistant Mycobacterium tuberculosis isolates in a high burden region

Clinical isolates with discordant phenotypic and genotypic results were submitted to DNA sequencing to identify which were genuinely resistant to rifampin and determine the frequency of silent and disputed mutations in our region. We present the retrospective analysis of all the culture-proven TB cases tested with the Xpert®MTB/RIF assay at the Tuberculosis Clinic and Laboratory of the Tijuana General Hospital, Mexico. Clinical isolates showing a discrepancy between phenotypic and molecular tests were analyzed by DNA sequencing. Thirteen isolates tested as rifampin susceptible on the MGIT system were rifampin-resistant according to Xpert®MTB/RIF assay. DNA sequencing showed that seven (53.8%) isolates had a silent (P514P) mutation; three isolates showed different missense (L511P, D516Y, and S531L) mutations. Three isolates showed no mutations.The existence of heteroresistance and silent or disputed mutations warrants that all rifampin-resistance cases diagnosed with the Xpert®MTB/RIF should be referred to specialized centers for DNA sequencing.     

结核分枝杆菌利福平分子药敏结果与其表型药敏差异的研究

目的 分析结核分枝杆菌利福平耐药的分子药敏(Xpert MTB/RIF)检测与在表型药敏(Bactec MGIT 960)检测结果不一致的机制。 方法 从2015年10月－2018年4月在长沙医学院第一附属医院进行 Xpert MTB/RIF 检测的8 274位患者中筛选出 Xpert MTB/RIF 检测利福平耐药而 Bactec MGIT 960 利福平敏感的患者39例,以及Xpert MTB/RIF 检测利福平敏感而 Bactec MGIT 960 利福平耐药的患者7例,共46例患者标本复苏其分离株,然后提取基因组DNA并进行rpoB的利福平耐药决定区域(rifampicin resistance determining region, RRDR)测序,同时对所有复苏的分离株进行最低抑菌浓度(minimum inhibitory concentration, MIC)测定,观察不同突变菌株的耐药程度。 结果 46例患者中有2例菌株复活失败、2例菌株丢失,剩下42例菌株完成测序,其余有5株菌株RRDR区未发生突变,剩余的37株在rpoB基因的RRDR区有不同位点及不同类型的变异,其中有2株在508和509位点发生缺失突变,其它突变的位点有511、516、526、531、533。多数突变位点集中在526位,突变类型包括His526Asn、His526Leu、His526Gly、His526Cys四种,其余位点突变形式为Leu511Pro、Asp516Tyr、Leu533Pro。在511、516、526、533位点突变中,MIC测定除了一株突变类型为His526Leu的菌株为32 μg/ml外,其余位点突变均表现为低水平耐药或敏感,而531位点突变中Ser531Trp、Ser531Leu均表现为高水平耐药。 结论 基于rpoB测序和MIC测定的结果显示特定rpoB基因突变可能导致结核分枝杆菌利福平耐药水平的改变,结核分枝杆菌利福平耐药(Xpert MTB/RIF)检测与(Bactec MGIT 960)检测结果不一致。     

中国西北部两省区结核分枝杆菌临床分离株Spoligotyping分型初步分析

目的初步了解新疆和甘肃结核分枝杆菌的基因型、主要流行型及其分布特点,比较两省区之间基因型分布。方法采用随机抽样的方法挑选新疆地区结核分枝杆菌临床分离株179株,甘肃地区结核分枝杆菌临床分离株176株,采用间隔寡核苷酸分型(Spoligotyping)技术对所收集的临床分离株进行分型研究,分析我国西北部相邻的两省区结核分枝杆菌的基因型分布、主要流行型及其地区特征。结果新疆地区菌株分为47个基因型,其中28个基因型为新的型别,新疆菌株中北京家族占68.72%(123/179),其次为T家族(6.70%,12/179),H家族(3.91%,7/179)和CAS家族(2.23%,4/179);甘肃地区菌株分为29种基因型,其中10个基因型为新的型别,甘肃菌株中北京家族占86.93%(153/176),其次为T家族(4.55%,8/176),H家族(1.14%,2/176),MANU2(1.14%,2/176)和CAS(0.57%,1/176)。结论北京基因型菌株在新疆和甘肃地区均为主要流行株,但甘肃地区北京基因型菌株比例明显高于新疆地区。     

Genotype analysis of Mycobacterium tuberculosis isolates from a sentinel surveillance population

As part of the National Tuberculosis and Genotyping Surveillance Network, isolates obtained from all new cases of tuberculosis occurring in seven geographically separate surveillance sites from 1996 through 2000 were genotyped. A total of 10883 isolates were fingerprinted by the IS6110-restriction fragment length polymorphism method, yielding 6128 distinct patterns. Low-copy isolates (those with six or fewer bands) were also spoligotyped. The distribution of specific genotype clusters was examined. Databases were also examined for families of related genotypes. Analysis of IS6110 patterns showed 497 patterns related to the W-Beijing family; these patterns represent 946 (9%) of all isolates in the study. Six new sets of related fingerprint patterns were also proposed for isolates containing 6-15 copies of IS6110. These fingerprint sets contain up to 251 patterns and 414 isolates; together, they contain 21% of isolates in this copy number range. These sets of fingerprints may represent endemic strains distributed across the United States.     

浙江地区耐多药结核分枝杆菌基因突变特征分析

目的 分析浙江地区耐多药结核分枝杆菌(M.tuberculosis complex,MTBC)异烟肼(isoniazid,INH)和利福平(rifampicin,RIF)耐药相关基因突变特征.方法 对患者痰标本阳性培养物进行菌种鉴定,提取耐多药菌株DNA,应用PCR法对inhA、katG和rpoB RRDR区进行扩增,...     

河南省结核菌分离株26位点MIRU-VNTR和Spoligotyping分子分型及耐药分析

目的 探讨河南省结核杆菌的遗传多样性。方法 使用26位点（经典24位点和其他2位点）的分支杆菌散在重复单元中数目可变串联重复序列（mycobacterium interspersed repetitive unit-variable number tandem repeat,MIRU-VNTR）和间隔区寡核苷酸分型（spoligotyping）对来自2015年期间河南省不同地区的668株结核杆菌分离株进行分型分析。对结核菌spoligotype类型和耐药表型的相关性进行分析。结果 Spoligotyping分析表明668株结核杆菌被分到10个不同的基因簇中。北京家族基因型是河南地区结核杆菌中的优势菌株。北京家族基因型菌株对四种一线药全耐药以及耐多药菌株比例明显高于非北京型菌株。668株结核杆菌通过26位点VNTR被分为567个不同的基因型。26个位点中15个位点具有高度或适中的分辨能力。10个分辨能力最强位点的组合分辨力能与26位点相当。结论 北京家族是河南省最流行的结核杆菌基因型。10位点VNTR和spoligotyping相结合可有效地用于河南省结核杆菌进化遗传学研究。     

Molecular epidemiology of tuberculosis in a sentinel surveillance population

We conducted a population-based study to assess demographic and risk-factor correlates for the most frequently occurring Mycobacterium tuberculosis genotypes from tuberculosis (TB) patients. The study included all incident, culture-positive TB patients from seven sentinel surveillance sites in the United States from 1996 to 2000. M. tuberculosis isolates were genotyped by IS6110-based restriction fragment length polymorphism and spoligotyping. Genotyping was available for 90% of 11923 TB patients. Overall, 48% of cases had isolates that matched those from another patient, including 64% of U.S.-born and 35% of foreign-born patients. By logistic regression analysis, risk factors for clustering of genotypes were being male, U.S.-born, black, homeless, and infected with HIV; having pulmonary disease with cavitations on chest radiograph and a sputum smear with acid-fast bacilli; and excessive drug or alcohol use. Molecular characterization of TB isolates permitted risk correlates for clusters and specific genotypes to be described and provided information regarding cluster dynamics over time.     

71株浙江省结核分枝杆菌临床分离株MLVA基因分型研究

目的初步探讨浙江省结核分枝杆菌的数目可变串联重复序列（VNTR）的分型及分布特征。方法随机选取浙江省结核分枝杆菌临床分离菌株，常规培养，收集菌体，提取基因组DNA，采用聚合酶链反应（PCR）分别对VNTR位点进行检测分析，基因分型聚类分析采用BioNumerics软件。结果对71株结核分枝杆菌临床分离株的15个VNTR位点进行检测。结果显示明显的基因多态性。经基因聚类分析，可分4个基因群（I群、Ⅱ群、Ⅲ群、Ⅳ群），58个基因型。分别为I群占8．5％，含5个基因型，Ⅱ群占18．3％，含13个基因型，Ⅲ群占70．4％，含38个基因型，Ⅳ群占2．8％，含2个基因型。结论初步证实浙江省结核分枝杆菌VNTRs基因存在明显的多态性，至少存在4个VNTR型，主要流行型为Ⅲ型。     

Spatio-temporal distribution analysis of circulating genotypes of dengue virus type 1 in western and southern states of India by a one-step real-time RT-PCR assay

Dengue virus type 1 (DENV-1) Asian and American/African (AM/AF) genotypes were reported to be co-circulating in southern and western states of India based on envelope (E) gene sequencing of few representative samples. The objective of the present study was to develop a one-step real-time RT-PCR to discriminate between Asian and AM/AF genotypes of DENV-1 and investigate the spatio-temporal distribution of the DENV-1 genotypes in southern and western states of India. A one-step real-time RT-PCR to discriminate the Asian and AM/AF genotypes of DENV-1 was developed and validated using 40 samples (17 Asian and 23 AM/AF), for which the envelope (E) gene sequence data was available. DENV-2, DENV-3 and DENV-4 isolates, one each and DENV negative samples (n = 17) were also tested by the assay. Additional 296 samples positive for DENV-1 from selected Southern and Western states of India were genotyped using the real-time RT-PCR assay. Among the samples used for validation, the genotyping results were concordant with sequencing results for 39 samples. In the one discordant sample which was positive for AM/AF by sequencing, the genotyping assay tested positive for both Asian and AM/AF genotype. DENV-2, DENV-3 and DENV-4 isolates were not reactive in the assay. None of the DENV negative samples were positive (sensitivity 100% and specificity 98.2%). A total of 336 samples (40 samples with sequence data and 296 samples without sequence data) were used for spatio-temporal distribution analysis. The results revealed that the Asian genotype was the predominant genotype in Tamil Nadu and Kerala, the southern states. The AM/AF genotype was the predominant genotype in Maharashtra, a western state of India. In Nashik district of Maharashtra, Asian genotype was observed in 32.6% of DENV-1 samples during 2017 while the same decreased to 7.3% during 2018. In Pune district, Asian genotype was observed in 40.0% of DENV-1 samples during 2018 only. To conclude, a one step real-time RT-PCR has been developed for discriminating Asian and AM/AF genotypes of DENV-1. This assay can act as a complement to sequencing but not a substitute and can be utilized in resource limited settings for molecular surveillance of DENV-1. DENV-1 Asian genotype was the dominant genotype in South India while, AM/AF genotype was dominant in Western India.     

感染乙型肝炎病毒不同基因型和亚型患者的临床特点分析

目的明确乙肝病毒不同基因型和亚型在国内的分布及其与病情的相关性。方法收集来自国内8个地区884例慢性乙型肝炎病毒感染者的血清和临床资料,用PCR-RFLP方法鉴定病毒基因型和亚型,分析不同基因(亚)型与病情间的相关性。结果乙肝病毒B(20.77%)和C (78.22%)基因型为最常见,仅1例为D基因型;所有B基因型均为Ba亚型,C基因型中仅发现C2和C1亚型。北方地区患者多感染C基因型(83.62%)/C2亚型(90.32%)。B基因型患者的年龄明显小于C基因型患者(P<0.000)。不同年龄段B基因型和C基因型比较发现,感染B基因型的患者在30岁以下、30～50岁和50岁以上年龄段中所占比例逐渐下降,感染C基因型的患者比例呈现相反趋势(P=0.000)。C1和C2亚型患者的年龄相近。各基因型在肝硬化、慢乙肝和无症状携带者中的分布无差别。B和C基因型(C1和C2亚型)患者的病毒量之间无差别。B基因型患者的肝脏炎症和纤维化评分明显低于C型患者(P<0.05)。结论北方地区以C基因型和C2亚型为主。B基因型患者的年龄明显小于C基因型。B和C基因型(C1和C2亚型)患者的肝脏炎症和病毒量之间无差别。B基因型患者的肝脏炎症和纤维化评分明显小于C型患者。     

Pandrug-resistant Acinetobacter baumannii causing nosocomial infections in a university hospital,Taiwan

The rapid emergence (from 0% before 1998 to 6.5% in 2000) of pandrug-resistant Acinetobacter baumannii (PDRAB) was noted in a university hospital in Taiwan. To understand the epidemiology of these isolates, we studied 203 PDRAB isolates, taken from January 1999 to April 2000: 199 from 73 hospitalized patients treated at different clinical settings in the hospital and 4 from environmental sites in an intensive-care unit. Pulsed-field gel electrophoresis analysis and random amplified polymorphic DNA (RAPD) generated by arbitrarily primed polymerase chain reaction of these 203 isolates showed 10 closely related genotypes (10 clones). One (clone 5), belonging to pulsotype E and RAPD pattern 5, predominated (64 isolates, mostly from patients in intensive care). Increasing use of carbapenems and ciprofloxacin (selective pressure) as well as clonal dissemination might have contributed to the wide spread of PDRAB in this hospital.