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中国防痨杂志 ›› 2021, Vol. 43 ›› Issue (7): 659-663.doi: 10.3969/j.issn.1000-6621.2021.07.004

• 论著 • 上一篇    下一篇


赵国连(), 谈小文, 崔晓利, 党丽云   

  1. 710100 西安市胸科医院
  • 收稿日期:2021-02-01 出版日期:2021-07-10 发布日期:2021-07-09
  • 通信作者: 赵国连

Analysis of gene polymorphism of Mycobacterium tuberculosis with negative MPT64 antigen in culture filtrate

ZHAO Guo-lian(), TAN Xiao-wen, CUI Xiao-li, DANG Li-yun   

  1. Xi’an Chest Hospital, Xi’an 710100, China
  • Received:2021-02-01 Online:2021-07-10 Published:2021-07-09
  • Contact: ZHAO Guo-lian

摘要: 目的 分析培养滤液MPT64抗原检测阴性结核分枝杆菌(MTB)MPT64的基因多态性。 方法 采用回顾性分析的方法,收集2018年1月至2020年6月于西安市胸科医院经痰液、支气管肺泡灌洗液、胸腹腔积液等标本分枝杆菌BACTEC MGIT 960液体培养(简称“MGIT 960液体培养”)阳性且经分枝杆菌萋-尼抗酸染色镜检确认为阳性,并有MPT64抗原检测(胶体金免疫层析法)、对硝基苯甲酸/噻吩-2-羧酸肼(PNB/TCH)生长试验和分枝杆菌菌种鉴定(DNA微阵列芯片法)结果的1962例患者的分枝杆菌临床分离株。对其中MPT64抗原检测与分枝杆菌菌种鉴定结果不一致的菌株行GeneXpert MTB/RIF和PNB培养检测,并对MPT64抗原检测阴性但菌种鉴定结果为MTB的14株菌株进行MPT64基因测序。 结果 1962株分枝杆菌临床分离株中,88株(4.5%)为非结核分枝杆菌,1874株(95.5%)为MTB,其中经MPT64抗原检测阴性菌株分别为87株(98.9%)和14株(0.7%)。MPT64基因测序结果显示,14株MPT64抗原检测阴性的MTB临床分离株发生MPT64蛋白基因第197~259位核苷酸缺失突变致第66~86位氨基酸缺失者达92.9%(13/14);另1株MPT64蛋白基因在第587位点插入了1361 bp的IS6110基因片段。 结论 MPT64蛋白基因第197~259位核苷酸缺失突变可能是导致MTB菌株MPT64抗原检测出现假阴性的主要原因,而IS6110片段的插入也可能导致MTB菌株MPT64抗原检测出现假阴性。

关键词: 分枝杆菌, 结核, 抗原, 细菌, 多态性, 单核苷酸, 细菌蛋白质类

Abstract: Objective To analyze the gene polymorphism of Mycobacterium tuberculosis (MTB) with negative MPT64 antigen in culture filtrate. Methods A total of 1962 mycobacteria clinical isolates were collected from Xi’an Chest Hospital between January 2018 and June 2020 were retrospectively analyzed. The samples were from sputum, bronchoalveolar lavage fluid and pleural effusion, positive in BACTEC MGIT 960 and confirmed by Ziehl-Neelsen anti-acid dyeing method. They were also tested by MPT64 antigen detection (colloidal gold immune-chromatography), p-nitrobenzoic acid/thiophene-2-carboxylic acid hydrazide (PNB/TCH) growth test and mycobacterial species identification (DNA microarray chip method). When results of MPT64 antigen test and the mycobacterial species identification was not inconsistent, GeneXpert MTB/RIF and PNB culture test were performed. MPT64 gene sequencing was performed on 14 strains identified as MTB but negative in MPT64 antigen test. Results Among the 1962 clinical isolates of mycobacteria, 88 (4.5%) were NTM and 1874 (95.5%) were MTB. By MPT64 antigen detection, 87 non-tuberculous mycobacteria (98.9%) and 14 MTB (0.7%) were negative. The results of MPT64 gene sequencing showed that 92.9% (13/14) of the 14 MTB clinical isolates negative in MPT64 antigen detection had mutations in nucleotides 197-259 and amino acid deletions at positions 66-86 of the MPT64 protein gene, and the other one had an IS6110 gene fragment of 1361 bp inserted at position 587. Conclusion The main reason for the false negative detection of the MTB strain in MPT64 antigen test might be the deletion mutation of nucleotides 197-259 of the MPT64 protein gene, and the insertion of IS6110 fragment might also cause the false negative detection.

Key words: Mycobacterium tuberculosis, Antigens, bacterial, Polymorphism, single nucleotide, Bacterial proteins