聚合酶链反应检测结核分枝杆菌DNA诊断关节结核的临床评价

目的评价聚合酶链反应(polymerase chain reaction,PCR)检测关节结核标本结核分枝杆菌脱氧核糖核酸(deoxyribonucleic acid,DNA)诊断关节结核的临床价值。方法对20份标准标本(5份结核分枝杆菌标准菌株、5份卡介苗和10份其它细菌标本)分别应用PCR盲法检测结核分枝杆菌DNA。对95例关节结核标本和98例非关节结核标本分别应用PCR检测结核分枝杆菌DNA。应用疾病诊断方法的临床评价原则对PCR诊断关节结核的敏感性、特异性和准确性进行评价。结果 (1)20份标准标本PCR检测中,结核分枝杆菌和卡介苗均为阳性,而其它细菌均为阴性;(2)95例关节结核标本中,PCR阳性78例、阴性17例;98例非关节结核标本中,PCR阳性9例、阴性89例;(3)PCR检测关节结核标本结核分枝杆菌DNA的敏感性为82.11%、特异性为90.81%、准确性为86.60%、阳性预测值为89.80%、阴性预测值为84.00%;(4)PCR整个检测过程自动化控制,可在3~6h内完成。结论 PCR是一种敏感、特异、快速、简便、无创、标本微量的关节结核标本结核分枝杆菌检测方法,对于关节结核的早期、快速诊断与鉴别诊断具有极其重要的临床价值。     

EDTA修复肉芽肿组织中荧光定量PCR检测结核杆菌的应用

目的观察EDTA热修复炎性肉芽肿组织石蜡切片,能否提高荧光定量PCR结核/非结核分枝杆菌的检出率。方法对125例炎性肉芽肿组织石蜡切片结核/非结核分枝杆菌同时进行常规荧光定量PCR检测和EDTA热修复后荧光定量PCR检测。结果常规荧光定量PCR检测检出分枝杆菌75例(60%)阳性,其中结核杆菌74例(59.2%),非结核分枝杆菌1例(0.8%),阳性病例平均阳性基因拷贝数6.35×105/ml/例;EDTA修复后荧光定量PCR检测检出分枝杆菌88例(70.4%),其中结核杆菌83例(66.4%),非结核分枝杆菌5例(4%),阳性病例平均阳性基因拷贝数7.36×106/ml/例。两组间差异均有统计学意义(P0.05,P0.01)。结论 EDTA热修复后荧光定量PCR检测可以大幅度提高炎性肉芽肿组织石蜡切片的结核/非结核分枝杆菌的阳性检出率。     

qPCR检测结核杆菌在肺和胸膜上皮样肉芽肿性疾病诊断中的意义

目的探讨荧光定量聚合酶链反应(Real-time polymerase chain reaction,q PCR)法在诊断及鉴别诊断肺和胸膜结核病和其他肉芽肿性疾病中的意义。方法收集经病理学检查发现上皮样肉芽肿性病变的肺和胸膜活检的石蜡包埋组织142例,应用q PCR法检测结核分枝杆菌DNA,同时行抗酸染色,并与临床资料对比进行回顾性分析。结果在142例肺胸膜活检标本中,60例临床诊断确诊为结核病。采用q PCR法检测结核分枝杆菌DNA阳性者58例,敏感性为96.67%,特异性为100%;抗酸染色阳性者17例,敏感性为28.33%,特异性为97.56%,差异有统计学意义(χ~2=21.47,P0.001)。结论结核分枝杆菌核酸检测有助于在石蜡包埋的肺和胸膜小活检组织中快速、准确的诊断结核病,可用于疑似结核的肉芽肿性病变的鉴别诊断。     

荧光定量PCR检测病理组织中结核分枝杆菌的临床价值

目的探讨应用荧光定量PCR（FQ-PCR）技术在病理组织中检测结核分枝杆菌DNA（TB-DNA）的临床应用价值。方法对196例临床诊断结核的穿刺病理活检标本进行石蜡包埋切片,采用实时荧光定量PCR技术检测TB．DNA,并行抗酸染色及组织病理学检查,对三种检测与临床诊断符合率进行比较。结果在196例临床诊断结核的石蜡包埋组织中,荧光定量PCR检测阳性136例,阳性率为69．39％,抗酸染色检测阳性69例,阳性率为35．20％,组织病理学检查阳性102例,阳性率为52．04％,荧光定量PCR检测阳性率最高。结论荧光定量PCR技术简便、快捷,敏感性强、特异性高,可作为结核病分子病理诊断的重要检测方法,具有较高的临床应用价值。     

PCR法检测结核分枝杆菌DNA在鉴别克罗恩病与肠结核中的价值

 目的：评估聚合酶链反应（PCR）技术检测通过活检或手术获取的肠道组织石蜡标本中结核分枝杆菌（Mycobacterium tuberculosis,MTB）DNA在鉴别克罗恩病（Crohn disease, CD）和肠结核（intestinal tuberculosis, ITB）中的可行性及价值。方法：根据来自MTB的重复插入序列IS6110设计引物,用PCR技术检测CD与ITB肠道组织蜡块标本中MTB DNA,利用基因直接测序法验证结果,分析PCR检测结果与病理特征间的关系。结果：ITB组MTB DNA检出率为32%,CD组MTB DNA检出率为0%,MTB DNA PCR法在ITB和CD鉴别诊断中的灵敏度为32%,显著高于抗酸染色（8%）和干酪样坏死（12%）（P<0.05）。MTB DNA PCR法在ITB和CD鉴别诊断中的特异度为100%,阳性预测值为100%,阴性预测值为59.5%。MTB DNA PCR阳性率在肉芽肿或多核巨细胞病理特征的标本中存在升高趋势,但差异无统计学意义。测序结果与PCR判读的结果相符。结论：PCR法用于MTB DNA检测,有助于ITB确诊,在ITB和CD的鉴别诊断中不失为一种方便快捷的病原学诊断方法。     

结核分枝杆菌稳定L型感染检测方法的研究

目的探讨结核分枝杆菌稳定L型感染标本的病原学的检测方法。方法以非高渗分离培养法诱导并获得结核分枝杆菌稳定L型纯培养物,将其感染豚鼠后进行病原体分离培养．采用PCR方法检测稳定L型培养物的IS986序列并鉴定其性质。结果结核分枝杆菌稳定L型在常规细菌学方法检查中不能发现或鉴定,但采用非高渗分离培养法能够检出,5例动物病变组织有4例检测出稳定L型,PCR直接扩增动物病变组织有3例呈阳性反应。结论采用以非高渗分离培养和基因检测为主要内容的非高渗分离培养法．能够快速的检测出样品中潜伏存在的结核分枝杆菌稳定L型．可提高病原学诊断的阳性率和特异性．     

即时荧光聚合酶链反应对结节病组织中结核杆菌DNA的检测

目的探讨结核分枝杆菌感染与结节病发病的关系。方法用即时荧光聚合酶链反应法检测了22例结节病患者活检样本中特异性结核分枝杆菌复合物IS6110DNA片段。结果22例结节病患者中,检测阳性11例。聚合酶链反应扩增所得到的IS6110DNA片段,经进一步测序证实与结核分枝杆菌基因序列完全一致。结论结核分枝杆菌感染可能是结节病的重要病因之一。     

荧光PCR法检测石蜡标本中结核分枝杆菌的流程改进

<正>结核分枝杆菌的检测对于有肉芽肿性炎特征组织病变的病理诊断具有重要的参考意义。目前,病理科常用的检测方法有基于细菌学的抗酸染色、金胺O荧光染色,基于分子病理学的PCR、Xpert MTB/RIF检测^[1-2]等。其中荧光PCR技术具有敏感性高、特异性好、速度快,且价格实惠的特点,被广泛应用于大中型医院病理科福尔马林固定石蜡包埋（formalin-fixed paraffin-embedded,FFPE）组织的结核分枝杆菌的检测中^[3-6]。由于石蜡组织标本中的病菌分布不稳定,     

恒温扩增检测结核分枝杆菌特异性IS6110片段在肺结核检测中的应用

目的 比较恒温扩增技术检测、抗酸杆菌涂片、结核分枝杆菌培养在肺结核患者检测中的应用.方法 收集2016年1月1日至12月31日我院呼吸科肺结核患者清晨痰液,将标本分为3份,分别进行痰涂片抗酸染色,结核菌培养及恒温扩增检测结核分枝杆菌特异性IS6110片段,统计分析3种方法的检测结果.结果 56例痰标本,恒温扩增检测结核分枝杆菌特异性IS6110片段阳性33例,阳性率为58.93％,抗酸染色阳性15例,阳性率为26.79％,恒温扩增检测结核分枝杆菌特异性IS6110片段阳性率高于抗酸染色方法;结核分枝杆菌培养阳性为35例,阳性率62.50％;恒温扩增检测结核分枝杆菌特异性IS6110片段和结核分枝杆菌培养两种方法检测Kappa系数为0.776,检测一致性较好.结论 恒温扩增检测结核分枝杆菌特异性IS6110片段是一种简便、高灵敏度的检出结核分枝杆菌的方法.     

石蜡包埋组织结核分枝杆菌检测方法的对比分析

结核病是由结核分枝杆菌引起的极具危害性的肉芽肿性病变,以肺结核最为常见.目前,组织病理学检查已成为结核病诊断的重要手段.抗酸染色作为结核病主要辅助检查手段,其灵敏度、特异性均较低[1 -2].《中国结核病病理学诊断专家共识》提出结核病的病理诊断标准:根据结核病的病理变化及结核分枝杆菌基因检测阳性才能作出明确诊断.文献报...     

Diffuse pulmonary disease caused by nontuberculous mycobacteria in immunocompetent people (hot tub lung)

The clinicopathologic spectrum of infections due to nontuberculous mycobacteria (NTM) includes cavitary disease, opportunistic infection, and nodular disease associated with bronchiectasis. We report a less well-described manifestation of NTM infection: 10 immunocompetent patients without preexisting bronchiectasis had radiographic evidence of diffuse infiltrative lung disease. The most common symptoms were dyspnea, cough, hypoxia, and fever. All 10 patients had used a hot tub. Histologic examination revealed exuberant nonnecrotizing, frequently bronchiolocentric, granulomatous inflammation in all cases. In 1 case, necrotizing granulomas were also noted. The inflammation often was associated with patchy chronic interstitial pneumonia and organization. Cultures revealed NTM in all cases (Mycobacterium avium complex in all but 1 case), but staining for acid-fast bacilli was positive in only 1 case. Four patients received corticosteroids alone for presumed hypersensitivity pneumonia, 4 were treated with antimycobacterial therapy, and 2 received both. All patients demonstrated significant improvement at the time of follow-up. These findings suggest that disease due to NTM may manifest as diffuse infiltrates in immunocompetent adults and that hot tub use may be an important risk factor for this disease pattern.     

Application of molecular biology techniques to the diagnosis of nontuberculous mycobacterial infections

A total of 19,723 clinical samples were cultivated for the detection of mycobacteria from January 1995 to March 2001. The 203 strains of nontuberculous mycobacteria isolated were identified with the use of molecular techniques in combination with traditional biochemical tests. The molecular methods applied were PCR-restriction fragment length polymorphism analysis (PRA) alone or in combination with 16S rRNA and 16S-23S spacer sequencing. The patient records of those with specimens positive for mycobacteria were analysed to evaluate the clinical significance of the culture results. Twenty-five of the 124 patients analysed (20%) were regarded as having clinical mycobacteriosis. The main species associated with mycobacteriosis were: Mycobacterium avium (13 cases), M. intracellulare (2 cases), M. kansasii (5 cases), M. chelonae (2 cases), M. malmoense (1 case), M. scrofulaceum (1 case) and M. marinum (1 case). The use of PRA alone or in combination with gene sequencing provided valuable help in discerning mycobacteria at both the intra- and interspecies level, thus contributing to a faster and more efficient diagnosis and epidemiological follow-up.     

Characterization of the first report of Mycobacterium timonense infecting an HIV patient in an Ecuadorian hospital

Mycobacterium timonense is a non-tuberculous mycobacteria (NTM) described in southern France in 2009, and to our knowledge, not reported again as a human pathogen in indexed literature. The aim of this work was to characterize the first clinical isolate of M. timonense in Ecuador. Time of growth, biochemical tests, thin layer growth test, PCR-RFLP analysis of the hsp65 gene and MALDI-TOF spectra analysis were not able to identify the species. The species identification was achieved through sequencing of rrs, hsp65 and rpoB genes. The results highlight the necessity to set up a sequencing method to identify emerging NTM in Ecuadorian clinical facilities.     

Species identification of mycobacteria in paraffin-embedded tissues: frequent detection of nontuberculous mycobacteria.

Diagnosis of infections caused by mycobacteria, especially nontuberculous mycobacteria still represents a difficult task both in microbiology and pathology. The aim of this study was to determine the frequency of mycobacterial DNA detectable by PCR in formalin-fixed paraffin-embedded tissues showing suspicious granulomatous lesions. A total of 190 archival specimens were analyzed, using a nested PCR protocol, which amplifies a fragment of the mycobacterial 65-kDa heat-shock protein gene. Restriction fragment-length polymorphisms and sequencing were utilized to further analyze the obtained PCR products. Corresponding microbiological culture results were available for 41 cases. We detected mycobacterial DNA in 119 cases (63%), of which 71 (60%) were positive for Mycobacterium tuberculosis complex DNA and 41 (34%) for DNA of nontuberculous mycobacteria. Seven cases (6%) could not be subtyped for technical reasons. The largest group of nontuberculous mycobacteria comprised 29 cases (25% of the 119 positive cases), which were assigned to Mycobacterium fortuitum complex. Mycobacterium avium-intracellulare complex was detected in eight (7%) cases, Mycobacterium gordonae in three (2.5%) and Mycobacterium rhodesiae in a single case (0.8%). All cases of Mycobacterium tuberculosis were unequivocally identified by restriction fragment-length polymorphism analysis. In contrast, sequencing provided a gain of information over restriction fragment-length polymorphism analysis in 37% of the nontuberculous mycobacteria cases (15 of 41). Alignment studies on DNA of nontuberculous mycobacteria showed frequent sequence variations, supporting the existence of sequevars. Comparison of molecular data to available results of microbiological culture assays showed a good concordance of 83%. In conclusion, amplification and sequencing of the mycobacterial 65-kDa heat-shock protein gene is an excellent tool for species identification of mycobacteria, especially nontuberculous mycobacteria, in formalin-fixed paraffin-embedded tissues.     

Genitourinary infections caused by nontuberculous mycobacteria at a university hospital in Taiwan, 1996–2008

Genitourinary infections caused by nontuberculous mycobacteria (NTM) are rarely reported. The medical records of all patients with genitourinary NTM infections treated at National Taiwan University Hospital from 1996–2008 were retrospectively reviewed. Fifteen patients were identified, of whom 10 (67%) were male. More than two-thirds of patients had underlying conditions, the most common of which was chronic renal disease. Only one patient had AIDS. Acid-fast smears of urine were negative in all patients. Eleven isolates were available for further confirmation by sequencing of the 16S rRNA gene. Mycobacterium avium complex was the most common (n = 5, 33%), followed by both Mycobacterium abscessus (n = 2; 13%) and Mycobacterium fortuitum (n = 2; 13%). Of the 12 patients receiving anti-NTM treatment, only four received adequate prescribed regimens and none died of NTM infections. Two patients died of refractory urosepsis before the urinary NTM infections were diagnosed. The clinical characteristics of the 15 patients were also compared with 43 previously reported patients with genitourinary tuberculosis. Patients with genitourinary NTM infections were more likely to report constitutional symptoms, seek medical help within 1 month after the onset of symptoms and develop leukocytosis. Patients with genitourinary tuberculosis were more likely to have ureteral strictures and abnormal chest radiographs associated with active or inactive tuberculosis. Although rare, genitourinary NTM infections pose a significant threat to life and should be considered in the differential diagnosis of genitourinary infections, especially when patients are unresponsive to conventional antibiotic treatment.     

Relatively alcohol-resistant mycobacteria are emerging pathogens in patients receiving acupuncture treatment

Acupuncture has been gaining popularity as a form of alternative medicine. In the past, only blood-borne viruses and anecdotal reports of bacterial infections have been associated with acupuncture. We report on four patients with mycobacterial infections complicating acupuncture who were encountered in a 2-year period. All had clinical and/or radiological lesions at acupuncture point- and meridian-specific locations. There was no other history of trauma or other clinical foci of infections, and the chest radiographs were normal. Histological studies of biopsy specimens of all four patients showed changes compatible with chronic inflammation, with granulomatous inflammation present in three patients and acid-fast bacilli present in two. Conventional biochemical tests and whole-cell fatty acid analysis for identification were inconclusive for all four nonpigmented mycobacteria recovered from tissue biopsies. 16S rRNA gene sequencing showed that the strains from two patients were Mycobacterium chelonae and that those from the other two were Mycobacterium nonchromogenicum. Alcohol resistance assay using the quantitative suspension test revealed that all four strains showed prolonged survival in 75% alcohol compared to other skin flora. Mycobacterial infections transmitted by acupuncture are an emerging problem. A high index of suspicion is essential to recognize this clinical syndrome, and strict implementation of proper infection control guidelines for acupuncture is mandatory.     

HAIN基因分型试剂盒鉴定临床非结核杆菌的应用研究

目的 采用HAIN基因分型试剂盒鉴定临床非结核分枝杆菌,评价其优缺点.方法 收集浙江、安徽等地74株临床非结核分枝杆菌,采用HAIN基因分型试剂盒鉴定临床非结核分枝杆菌,并用16S rRNA基因测序方法对其进行比较和评价.结果 74株非结核分枝杆菌HAIN基因分型试剂盒鉴定结果为:31株胞内分枝杆菌,12株脓肿分枝杆菌,8株偶发分枝杆菌,6株堪萨斯分枝杆菌,5株鸟分枝杆菌,3株耻垢分枝杆菌,2株草分枝杆菌,2株瘰疬分枝杆菌,1株戈登分枝杆菌,另外有4株菌株只能鉴定为分枝杆菌属,不能鉴定到种.8株结核分枝杆菌鉴定准确.与16SrRNA基因测序相比较,HAIN基因分型试剂盒除了4株菌株只能鉴定为分枝杆菌属以外,其余70株非结核分枝杆菌均能鉴定到种,鉴定符合率为94.59％;并且它能进一步区分脓肿分枝杆菌和龟分枝杆菌,以及堪萨斯分枝杆菌和胃分枝杆菌.如果单纯鉴定HAIN基因分型试剂盒菌株范围之内的临床最常见非结核分枝杆菌菌株,鉴定符合率为100％.结论 HAIN基因分型试剂盒鉴定临床非结核分枝杆菌时间短、操作简单、结果准确,可在临床推广使用.     

Polyclonal antibodies raised against Bacillus Calmette-Guerin, Mycobacterium duvalii, and Mycobacterium paratuberculosis used to detect mycobacteria in tissue with the use of immunohistochemical techniques.

Commercially available polyclonal antibodies raised against strains of mycobacteria were used to detect organisms in tissue sections from 34 cases of tuberculosis, leprosy, and atypical mycobacteria. Thirty-two cases of fungal infections, granulomatous inflammation, and sarcoidosis were used as negative controls. Sections stained with the use of antibodies raised against Bacillus Calmette-Guerin (BCG), Mycobacterium duvalii (MD), and Mycobacterium paratuberculosis (MP) were compared with Kinyoun and Fite-stained tissue sections. In caseating granulomata, clumps of mycobacterial debris, cells, and cell fragments stained. In histiocytic granulomata of mycobacterial infections, histiocyte cytoplasm contained both organisms and debris. The three antibodies showed cross-reactivity against the four groups of mycobacteria tested. Mycobacterial staining using immunoperoxidase was apparent in most cases at low-power (scanning) magnification. Thirty-two of 34 cases of mycobacterial infection, including all 24 Kinyoun-Fite-positive cases, were positive for immunoreactive organisms and debris using anti-MD, anti-BCG, and/or anti-MP. Eight of ten cases of culture-proven mycobacterial infection, in which Kinyoun and Fite stains were negative, had immunoreactive organisms or antigen with anti-BCG, MD, or MP. The antibodies also stained organisms in five cases of sporotrichosis in which the organisms were identified as yeast forms in tissue sections.     

Diagnosis and treatment of nontuberculous mycobacterial pulmonary diseases: a Korean perspective

The incidence of pulmonary disease caused by nontuberculous mycobacteria (NTM) appears to be increasing worldwide. In Korea, M. avium complex and M. abscessus account for most of the pathogens encountered, whilst M. kansasii is a relatively uncommon cause of NTM pulmonary diseases. NTM pulmonary disease is highly complex in terms of its clinical presentation and management. Because its clinical features are indistinguishable from those of pulmonary tuberculosis and NTMs are ubiquitous in the environment, the isolation and identification of causative organisms are mandatory for diagnosis, and some specific diagnostic criteria have been proposed. The treatment of NTM pulmonary disease depends on the infecting species, but decisions concerning the institution of treatment are never easy. Treatment requires the use of multiple drugs for 18 to 24 months. Thus, treatment is expensive, often has significant side effects, and is frequently not curative. Therefore, clinicians should be confident that there is sufficient pathology to warrant prolonged, multidrug treatment regimens. In all of the situations, outcomes can be best optimized only when clinicians, radiologists, and laboratories work cooperatively.     

Development and evaluation of a molecular assay for detection of nontuberculous mycobacteria by use of the cobas amplicor platform

We have developed and evaluated a semiautomated assay for detection of nontuberculous mycobacteria (NTM) from clinical samples based on the Cobas Amplicor Mycobacterium tuberculosis test (Roche Diagnostics, Switzerland). A capture probe, specific for mycobacteria at the genus level, was linked to magnetic beads and used for the detection of amplification products obtained by the Cobas Amplicor M. tuberculosis assay. We demonstrate that the analytical sensitivity of the genus assay is similar to that of Cobas Amplicor M. tuberculosis detection. Four hundred sixteen clinical specimens were evaluated for the presence of NTM DNA. Sensitivities for smear-positive and smear-negative specimens were found to be 100% and 47.9%, respectively. Specificity was 97.7%, the positive predictive value 84.6%, and the negative predictive value 93.1%. The genus assay is easy to perform, produces reliable results, and was found to be a valuable diagnostic tool for rapid diagnosis of infections with NTM. The genus assay has the potential to detect NTM not routinely recovered by culture and to discover new mycobacterial species.