16S DNA用于结核性胸膜炎的快速诊断

目的建立聚合酶链反应—毛细管电泳（PCR-CE）的方法直接检测结核性胸膜炎患者胸水中的结核分枝杆菌,以达到快速诊断结核性胸膜炎的目的。方法在大连市结核病医院收集2006年11月至2007年2月结核性胸膜炎患者的胸水120份,所有标本都经过结核分枝杆菌抗酸染色镜检和结合菌培养,其中115份为阴性标本,5份为阳性标本。利用16S DNA集保守性和变异性于一体的特点,设计合成通用引物G1：5′-FAM-GGC GGACGG GTG AGTAA-3′,G2：5′-ROX-GGA CTG CTG CCTCCC GTA G-3′,然后将标本进行DNA提取并进行PCR扩增,扩增产物用限制性内切酶HaeⅢ消化,用毛细管电泳来检测结核分枝杆菌。结果115份阴性标本中检测出结核分枝杆菌的有19份,未检测出结核分枝杆菌的有96份,其阳性率为16.52%;5份阳性标本中检测出结核分枝杆菌的有5份,阳性率为100%。结论PCR-CE方法检测结核分枝杆菌具有快速、准确、灵敏的特点,可用于结核性胸膜炎的快速诊断。     

复治肺结核患者结核分枝杆菌L型培养结果分析

目的:了解复治肺结核患者的结核分枝杆菌L型培养情况,探讨结核分枝杆菌L型阳性与耐多药的关系。方法:选择180例肺结核患者的痰标本进行结核分枝杆菌培养和结核分枝杆菌L型培养,同时对110例复治组中培养阳性的标本行耐药监测。结果:复治组的L型阳性率为43.6%,初治组的L型阳性率为15.7%,复治组显著高于初治组(P<0.01);菌阳复治组的L型阳性率50%,菌阴复治组的L型阳性率39.4%,菌阳组明显高于菌阴组(P<0.05);L型菌阳性患者的耐药率显著高于L型菌阴性组(P<0.05)。结论:结核分枝杆菌L型阳性是引起结核病复发、耐药的重要原因;MDR-TB与结核分枝杆菌L型感染有关。     

复治肺结核患者结核分枝杆菌L型培养结果分析

目的：了解复治肺结核患者的结核分枝杆菌L型培养情况,探讨结核分枝杆菌L型阳性与耐多药的关系。方法：选择180例肺结核患者的痰标本进行结核分枝杆菌培养和结核分枝杆菌L型培养,同时对110例复治组中培养阳性的标本行耐药监测。结果：复治组的L型阳性率为43．6％,初治组的L型阳性率为15．7％,复治组显著高于初治组（P〈0．01）;菌阳复治组的L型阳性率50％,菌阴复治组的L型阳性率39．4％,菌阳组明显高于菌阴组（P〈0．05）;L型菌阳性患者的耐药率显著高于L型菌阴性组（P〈0．05）。结论：结核分枝杆菌L型阳性是引起结核病复发、耐药的重要原因;MDR-TB与结核分枝杆菌L型感染有关。     

3种检测分枝杆菌方法的比较及应用价值分析

目的:比较并评价涂片抗酸染色法(涂片法)、L-J培养法和基因芯片法在分枝杆菌检测中的应用价值。方法:对241例需查抗酸杆菌的临床标本,采用涂片法、L-J培养法和基因芯片法检测分枝杆菌,3种方法检测结果存在分歧的标本再进行DNA测序,以培养鉴定结果阳性或DNA测序得到分枝杆菌序列为确诊标准。结果:241例标本,涂片法、L-J培养法和基因芯片法的检测阳性率依次为18.7%、12.0%、15.8%,经卡方检验三者阳性率的差异没有统计学意义(P0.05);检测灵敏度依次为85.4%、70.7%、93.0%,经卡方检验三种方法的灵敏度总体来说有差别(χ2=7.24,P0.05),涂片法与L-J培养法以及涂片法与基因芯片法的灵敏度差异没有统计学差异,基因芯片法的灵敏度高于涂片法(χ2=6.61,P0.05);检测特异性依次为95.6%、100.0%、100.0%。38例基因芯片检测阳性患者中有28例为结核分枝杆菌,10例为非结核分枝杆菌。结论:与涂片法及培养法相比较,基因芯片法能够鉴别分枝杆菌菌种,同时具有快速、可靠、准确度高的特点,在分枝杆菌感染的早期诊断和抗菌治疗上具有重要的临床价值。     

3种方法检测艾滋病患者血和脑脊液中隐球菌的结果分析

目的比较真菌培养、墨汁染色、侧向免疫层析法(LFA)检测艾滋病患者脑脊液和血标本中隐球菌的阳性率差异,以期为临床医生提供隐球菌感染理想的检测方法。方法采用回顾性分析,收集2017年本院就诊的1 049例AIDS患者的血液和脑脊液标本,进行真菌培养、侧向免疫层析法和脑脊液墨汁染色。数据分析应用SPSS 14.0软件。结果 1 049例AIDS患者,其血培养、隐球菌抗原检测、脑脊液培养和墨汁染色阳性率分别为2.8%(19/688)、10.96%(115/1 049)、9.18%(29/316)、17.99%(59/328),其中201例患者同时做了脑脊液和血标本的隐球菌抗原检测,阳性率分别为27.86%和37.31%,差异有统计学意义(P0.05)。292例AIDS患者同时做了脑脊液的墨汁染色和隐球菌抗原检测,阳性率分别为19.52%和23.97%,隐球菌抗原检测的阳性率大于墨汁染色法,差异无统计学意义(P0.05)。结论 3种方法检测结果显示侧向免疫层析法阳性率最高,比较脑脊液和血标本侧向免疫层析法阳性率,血标本阳性率较高,所以血标本侧向免疫层析法检测是诊断AIDS是否合并隐球菌感染的理想方法之一。     

DNA微阵列芯片在皮肤分枝杆菌感染中的早期诊断价值

目的研究DNA微阵列芯片在皮肤分枝杆菌感染早期诊断中的临床应用价值。方法应用传统方法(包括病理学以及培养和测序鉴定)和DNA微阵列芯片技术对6例临床疑似皮肤分枝杆菌感染患者的皮肤组织进行检测。结果 6例患者的发病诱因多有海鲜接触史或外伤史,表现为单发或是呈淋巴管样排列模式;传统的细菌培养有5例患者阳性,经过测序鉴定分别为海分枝杆菌4例、龟分枝杆菌1例;DNA微阵列芯片技术检测6例患者均为阳性,其中海分枝杆菌5例,龟分枝杆菌1例;DNA微阵列芯片技术阳性率(6/6)高于传统的培养技术(5/6),此外检测时间也远低于传统培养技术。结论DNA微阵列芯片技术具有简便、快速、高敏感等特点,可鉴定皮肤分枝杆菌感染的致病菌种,为临床做出早期诊断和治疗提供依据。     

应用PCR技术检测结核分枝杆菌的临床分析

采用聚合酶链反应（Ｐｏｌｙｍｅｒａｎｓｅ Ｃｈｉａｎ Ｒｅａｔｉｏｎ,即ＰＣＲ）技术检测结核分枝杆菌Ｍｙｃｏｂａｃｔｅｒｉｕｍ ｔｕｂｅｒｃｕｌｏｓｉｓ,一年多来共检测了１００例结核（肺、肾结核）患者的痰和尿液标本,结果ＰＣＲ检出阳性率为８１％,对照用储菌涂片抗酸染色法,阳性率为５８％,用常规培养法阳性率为２０％。而对５０例非结核患者的痰和尿液标本的检测,ＰＣＲ法仍有６％的阳性率,而用涂片或常规培     

时间对微生物标本检验阳性率的影响分析

目的:对不同检验时间的临床微生物标本的阳性率进行探讨。方法:回顾性分析我院2013年12月至2014年5月间住院治疗的2106例患者在不同检验时间进行临床微生物检验的临床资料。结果:第一时间血培养标本、非呼吸道标本的阳性检出率明显高于第二时间(10.23%/6.25%、35.16%22.14%),差异有统计学意义(P0.05);且第一时间呼吸道标本阳性率明显低于第二时间呼吸道标本的阳性率(28.92%/36.29%),差异有统计学意义(P0.05);但两时间粪便标本阳性率相同,均为2.40%。结论:对于临床微生物标本应尽量做到立即送检,以减少微生物繁殖、厌氧菌的过度生长等对微生物检验准确性的影响;同时,要加强临床检验人员专业素养、提升技术水平,从而提高微生物检验质量,为感染性疾病的诊治提供有利依据。     

应用基因芯片快速检测分枝杆菌

目的:将临床疑似分枝杆菌感染患者的标本用基因芯片方法进行分枝杆菌菌种鉴定,并将基因芯片检测的结果与传统的抗酸染色方法进行对比。方法:采用基因芯片PCR扩增、分子杂交、微阵列芯片扫描的方法检测379例临床疑似标本。结果:基因芯片阳性检出率为16.3%(62/379),涂片抗酸染色法阳性检出率为15.3%(58/379),两者差异无统计学意义(χ2=0.16,P>0.05);62例基因芯片检测阳性患者中有52例为结核分枝杆菌,另有10例为非结核分枝杆菌(其中3例偶然分枝杆菌,1例龟/脓肿分枝杆菌,1例堪萨斯分枝杆菌,4例浅黄分枝杆菌,1例海分枝杆菌)。结论:结合临床病例分析结果显示,基因芯片检测对鉴别结核分枝杆菌和非结核分枝杆菌分型具有快速、特异性高的特点,在分枝杆菌感染的早期诊断和治疗上具有重要的临床价值,值得推广和应用。     

浅部真菌病1948份临床标本的真菌学分析

目的 通过对浅部真菌病患者临床送检标本的病原真菌菌种进行系统分析,了解感染及病原真菌的分布情况。方法 采用直接镜检、培养及真菌鉴定等方法对临床送验标本进行检验和鉴定,大部分标本鉴定到种。结果 1948份临床送验标本中,直接涂片镜检阳性率53．41％,培养阳性率40．28％,而镜检＋培养的阳性率为66．98％。对上述3种方法的真菌检出率进行比较,均存在显著差异（χ^2检验P均〈0．005）。在培养的1944份标本中,共分离出18个属,36种真菌,其中,红色毛癣菌24．52％、须癣毛癣菌16．48％、白念珠菌12．64％。结论 ①镜检结合培养的阳性率显著高于单一的镜检或培养的阳性率。②在患者即时的真菌镜检阴性时,应选择培养方法进一步检测,不轻易排除浅部真菌病感染可能。③皮肤癣菌居患者浅部真菌病致病菌首位,而白念珠菌及酵母类菌也是重要病原菌。     

牛型纯化蛋白衍生物皮内变态反应试验阳性牛中分枝杆菌的分离与鉴定

为评价牛分枝杆菌纯化蛋白衍生物(purified protein derivative,PPD)单纯颈部皮内变态反应试验(single intradermal cervical tuberculin,SICT)在奶牛结核病检测中的特异性,采集54头SICT阳性牛的118份组织样品进行病原分离和鉴定。结果显示,14头SICT阳性牛样品中分离到抗酸阳性菌,占SICT阳性牛总数的25.9%(14/54)。其中,10头阳性牛样品中分离到分枝杆菌,占18.5%(10/54);1头阳性牛样品中分离到牛分枝杆菌,占1.9%(1/54)。从118份组织样品中分离到16株抗酸阳性菌,其中12株为分枝杆菌,分枝杆菌分离率为10.2%(12/118)。12株分枝杆菌中,1株为牛分枝杆菌,其余11株为禽分枝杆菌、土地分枝杆菌等非结核分枝杆菌。牛分枝杆菌与非结核分枝杆菌分别占分枝杆菌分离株的8.3%(1/12)和91.7%(11/12)。病原分离和鉴定结果表明,SICT阳性牛的牛分枝杆菌分离率较低,为确保检测结果的准确性,有必要采用其他检测方法进行验证。同时,可将分枝杆菌快速分离培养及菌种鉴定检测技术引入对皮内变态反应试验阳性牛的实验室诊断,进一步提高牛结核病检测的特异性。     

Predictive value of the acid fast smear for detection of Mycobacterium tuberculosis in respiratory specimens in a reference center of HIV/AIDS in Rio de Janeiro, Brazil

In order to evaluate the predictive value of acid fast bacilii (AFB) smear for the diagnosis of Mycobacterium tuberculosis in respiratory specimens in a setting with a high prevalence of AIDS and an unknown prevalence of nontuberculous mycobacteria (NTM), we retrospectively examined specimens cultured for mycobacteria between 1 September 1993 and 30 September 1994 and medical records of patients with positive culture in a General Hospital, AIDS reference in Rio de Janeiro, Brazil. Seventy three per cent (1517/2077) of samples were respiratory specimens and mycobacteria were recovered from 20.6% (313/1517) of these. M. tuberculosis was identified in 94.2% (295/313) and NTM in 5.8% (18/313). The yield of positive AFB smear and of positive culture was 6.1% (93/1517) and 20.6% (313/1517), respectively. The positive predictive value (PPV) of AFB for M. tuberculosis was 98.4% in expectorated sputum and 96.4% in bronchoalveolar lavage. Forty four percent (130/295) of specimens with positive culture for M. tuberculosis and 66.7% (12/18) for NTM were from patients HIV positive. The conclusion was that in our study population, the PPV of AFB for M. tuberculosis in respiratory specimens was high and the prevalence of NTM was low despite the high prevalence of HIV positive.     

2018—2020年平顶山地区非结核分枝杆菌菌种鉴定及耐药性分析

本文旨在观察2018—2020年河南省平顶山地区非结核分枝杆菌(nontuberculous mycobacteria,NTM)的菌种分布及耐药情况。收集2018年1月—2020年12月平顶山市传染病医院分离到的326株NTM,采用DNA微阵列芯片鉴定菌种,改良罗氏培养基比例法进行药敏试验。结果显示,从61～80岁患者中分离的NTM菌株最多,其次是41～60岁患者。共鉴定出8个NTM菌种,分别为胞内分枝杆菌(35.28%)、龟/脓肿分枝杆菌(24.85%)、鸟分枝杆菌(18.40%)、偶然分枝杆菌(5.21%)、戈登分枝杆菌(1.23%)、堪萨斯分枝杆菌(12.58%)、浅黄分枝杆菌(1.53%)、瘰疬分枝杆菌(0.92%)。NTM对异烟肼的耐药率最高,为97.85%。除戈登分枝杆菌外,其他NTM菌种对异烟肼的耐药率均＞94%;胞内分枝杆菌对丙硫异烟胺的耐药率(8.70%)相对较低,鸟分枝杆菌对丙硫异烟胺的耐药率为10.00%;龟/脓肿分枝杆菌对异烟肼、利福平、链霉素、乙胺丁醇、阿米卡星的耐药率均＞95%;偶然分枝杆菌对左氧氟沙星的耐药率为35.29%,堪萨斯分枝杆菌对左氧氟沙星的耐药率最低(7.32%);戈登分枝杆菌对异烟肼、乙胺丁醇、链霉素、对氨基水杨酸的耐药率均≥50%;浅黄分枝杆菌对乙胺丁醇、左氧氟沙星、阿米卡星、卡那霉素的耐药率均＜50%;瘰疬分枝杆菌对阿米卡星和丙硫异烟胺的耐药率为0。结果提示,2018—2020年河南省平顶山地区鉴定出的8个NTM菌种中,胞内分枝杆菌占比最高,不同菌种对不同抗结核药物的耐药性差异较大,因此菌种鉴定对临床治疗有重要意义。     

EVALUATION OF CORD FORMATION IN KINYOUN-STAINED SMEARS OF MGIT CULTURES AS A RAPID IDENTIFICATION METHOD FOR MYCOBACTERIUM TUBERCULOSIS COMPLEX

Tuberculosis (TB) is a major cause of morbidity and mortality worldwide. One hundred and nineteen acid-fast bacilli-positive smears for Mycobacterium Growth Indicator Tube cultures from 119 patients were examined by microscopy for the presence of cord formation. The results were compared with those of the traditional TB identification method, IS6110 polymerase chain reaction (PCR) , and the Capilia TB assay which uses a monoclonal antibody to identify. With the traditional TB identification method, 57 of these 119 specimens were determined to be positive for Mycobacterium tuberculosis complex, and the organisms in the remaining 62 specimens were identified as non-tuberculosis mycobacteria (NTM). Both IS6110 PCR and the Capilia TB assay yielded results identical to those of the traditional method with 57 true TB and 62 NTM. For the cord formation assay, all 62 NTM cultures were negative, but 54 of the 57 true TB cultures were positive. Therefore, the cord formation method had a sensitivity of 94.74% (54/57), specificity of 100% (62/62), negative predictive value of 95.38% (62/65) and positive predictive value of 100% (54/54) for identification of M. tuberculosis complex. The cord formation method is less expensive and 3–5 weeks quicker than the biochemical tests in the identification of M. tuberculosis.

PRACTICAL APPLICATIONS

Due to the slow growth of Mycobacterium tuberculosis bacilli, delays in the detection of TB infection may occur in clinical TB laboratories when only conventional methods for recovery of mycobacteria are used. This problem can be supported by other techniques, such as cord formation in Kinyoun-stained smears of Mycobacterium Growth Indicator Tube cultures and molecular biology-based systems, which can be used in combination to obtain accurate results in a much shorter period of time.     

Non‐Tuberculosis mycobacterium speciation using HPLC under Revised National TB Control Programme (RNTCP) in India

Aims

Non‐Tuberculous Mycobacteria (NTM) are ubiquitous in nature. The data on prevalence of NTM under the RNTCP is scarce. Many NTM species have clinical significance, and hence their identification and speciation are important.

Methods and Results

It is a cross‐sectional study conducted at the five RNTCP accredited culture and drug susceptibility testing (CDST) laboratory. The culture isolates from AFB positive but Immunochromatographic test negative samples were taken for identification and speciation using HPLC. Of the total 266 isolates only 164 isolates had a second sample received at the laboratory. The speciation was done using HPLC for those isolates. The type of species identified are: 26·8% (44) were Mycobacterium chelonae, 12·8% (21) were Mycobacterium fortuitum, 9% (15) were Mycobacterium gordonae, 9% (15) were Mycobacterium tuberculosis complex, 6·1% (10) were Mycobacterium kansasii, 4·9% (8) were Mycobacterium simiae, 2·4% (4) were Mycobacterium thermophile, 1·2% (2) were Mycobacterium gastri, 0·6% (1) were Mycobacterium scrofulaceum, 0·6% (1) were Mycobacterium avium and 4·9% (8) isolates had chromatogram which was un‐interpretable.

Conclusion

Identification and its speciation of NTM are not routinely done under TB control programme. Since HPLC could identify 95% of isolates belonging to 10 species, the speciation of NTM using HPLC should gain importance in the diagnosis of disease caused by NTM.

Significance and Impact of Study

NTM are emerging as important causative agents of pulmonary and extra pulmonary disease, the ability to recognize disease caused by NTM and subsequently treat such disease has become increasingly important. The identification of NTM up to its species level should gain importance in all TB reference Laboratories.     

利用rpoB基因芯片技术进行快速分枝杆菌菌种鉴定

利用rpoB基因芯片技术快速进行分枝杆菌菌种鉴定.以分枝杆菌rpoB基因编码序列为靶基因,用基因芯片技术检测21种分枝杆菌标准株;8种其它细菌标准株;126株临床分离株.分枝杆菌与其它细菌标准株经PCR扩增后,分枝杆菌标准株均扩增出360 bp DNA片段,在其它细菌中,除甲型溶血性链球菌和假白喉棒状杆菌出现同样片段外,其它细菌均未见扩增.21种寡核苷酸探针除海分枝杆菌与偶然分枝杆菌的探针有交叉杂交外,其余均为特异性杂交.对126株临床分离株进行鉴定,89株为结核分枝杆菌,占70.6%(89/126),非结核分枝杆菌(NTM)占9.2%(9/98).应用rpoB基因芯片技术鉴定分枝杆菌菌种,是一种快速、准确的方法,具有较高的临床应用价值.     

利用rpoB基因芯片技术进行快速分枝杆菌菌种鉴定

利用rpoB基因芯片技术快速进行分枝杆菌菌种鉴定。以分枝杆菌rpoB基因编码序列为靶基因, 用基因芯片技术检测21种分枝杆菌标准株;8种其它细菌标准株;126株临床分离株。分枝杆菌与其它细菌标准株经PCR扩增后, 分枝杆菌标准株均扩增出360 bp DNA片段, 在其它细菌中, 除甲型溶血性链球菌和假白喉棒状杆菌出现同样片段外, 其它细菌均未见扩增。21种寡核苷酸探针除海分枝杆菌与偶然分枝杆菌的探针有交叉杂交外, 其余均为特异性杂交。对126株临床分离株进行鉴定, 89株为结核分枝杆菌, 占70.6％(89/126), 非结核分枝杆菌(NTM)占9.2％(9/98)。应用rpoB基因芯片技术鉴定分枝杆菌菌种, 是一种快速、准确的方法, 具有较高的临床应用价值。     

Comparison of NaOH-N-acetyl cysteine and sulfuric acid decontamination methods for recovery of mycobacteria from clinical specimens

We compared the NaOH-N-acetyl cysteine (NaOH-NALC) and the sulfuric acid decontamination procedure in the detection of mycobacteria using the Mycobacteria Growth Indicator Tube (MGIT). In total 219 sputum specimens were collected from 142 Zambian patients and subjected to mycobacterial culture. One half of the specimen was decontaminated with NaOH-NALC and the other half was decontaminated with sulfuric acid. From the 438 samples a total of 261 (60%) cultures yielded growth of mycobacteria, consisting of 22 different species. The sulfuric acid method was more successful than the NaOH-NALC method in recovering mycobacteria in MGITs (146 versus 115 respectively, p = 0.001). Of the 146 positive mycobacterial cultures recovered after sulfuric acid decontamination 28 were Mycobacterium tuberculosis, 84 nontuberculous mycobacteria (NTM) and 34 acid fast bacterial isolates which could not be identified to the species level. The 115 mycobacteria recovered by the NaOH-NALC method consisted of 34 M. tuberculosis strains, 55 NTM and 26 acid fast bacteria that could not be identified. The most frequently isolated NTM were Mycobacterium lentiflavum and Mycobacterium intracellulare. Comparing the two decontamination methods the recovery of NTM in the sulfuric acid group was significant higher than in the NaOH-NALC group (p = 0.001). In contrast, no significant difference was found for the recovery of M. tuberculosis. These results show that the decontamination method used affects the recovery of nontuberculous mycobacteria in particular.     

2019—2020年上海地区儿童幽门螺杆菌感染及其耐药性分析

为分析2019—2020年上海地区儿童幽门螺杆菌感染及其对4种常用抗菌药物的耐药状况,本研究收集了2019年1月—2020年10月于复旦大学附属儿科医院就诊且经胃镜检查、快速尿素酶试验阳性的患儿1605例,取胃黏膜样本进行幽门螺杆菌分离培养及鉴定,采用E-test法进行体外药敏试验,分析不同年龄组患儿幽门螺杆菌耐药状况...     

Distribution of non-tuberculosis mycobacteria strains from suspected tuberculosis patients by heat shock protein 65 PCR–RFLP

The genus Mycobacterium contains more than 150 species. Non-tuberculosis mycobacteria (NTM) often cause extrapulmonary and pulmonary disease. Mycobacteria detection at species level is necessary and provides useful information on epidemiology and facilitates successful treatment of patients. This retrospective study aimed to determine the incidence of the NTM isolates and Mycobacterium tuberculosis (Mtb) in clinical specimens collected from Iranian patients during February 2011–December 2013, by PCR–restriction fragment length polymorphism analysis (PRA) of the hsp65 gene. We applied conventional biochemical test and hsp65–PRA identification assay to identify species of mycobacteria in specimens from patients suspected of having mycobacterial isolates. This method was a sensitive, specific and effective assay for detecting mycobacterial species and had a 100% sensitivity and specificity for Mtb and Mycobacterium avium complex (MAC) species. Using PRA for 380 mycobacterial selected isolates, including 317 Mtb, four Mycobacterium bovis and of the 59 clinical isolates, the most commonly identified organism was Mycobacterium kansasii (35.6%), followed by Mycobacterium simiae (16.9%), Mycobacterium gordonae (16.9%), Mycobacterium fortuitum (5.1%), Mycobacterium intracellulare (5.1%), Mycobacterium avium (5.1%), Mycobacterium scrofulaceum (3.4%), Mycobacterium gastri (3.4%), Mycobacterium flavescens (3.4%), Mycobacterium chelonae (3.4%) and Mycobacterium nonchromogenicum (1.7%). PRA method, in comparison with classical methods, is rapid, useful and sensitive for the phylogenetic analysis and species detection of mycobacterial strains. Mycobacterium kansasii is the most common cause of infection by NTM in patients with non-HIV and HIV which demonstrated a high outbreak and diversity of NTM strains in our laboratory.