Xinling Pan, Sujuan Zhou, Lulu Jin, Songjun Ji, Xingxing Lou, Bin Lu, Jin Zhao
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引用次数: 0
Abstract
Background: MPT64 protein is an effective marker for detecting Mycobacterium tuberculosis (MTB) in liquid culture and clinical tissue samples. However, some MTB clinical isolates test negative for this antigen because of varied mutation types across different regions.
Methods: DNA samples of MPT64 antigen assay-negative MTB strains were collected from a tertiary hospital from January 2016 to January 2024, and mpt64 gene mutations were detected by sequencing. Clinical records of patients with negative MPT64 antigen results were collected and compared with those of patients with positive results. The global distribution of mpt64 gene mutations was analyzed using MTB genome sequences from the National Center for Biotechnology Information (NCBI) database.
Results: Among 821 mycobacterial specimens with negative MPT64 antigen assay results, 77 MTB strains were collected from 73 patients. Compared with MPT64-positive patients (n = 301), a higher percentage of MPT64-negative patients had a history of anti-tuberculosis therapy (n = 7, 11.1%; P = 0.01). Moreover, MPT64-negative patients demonstrated a lower percentage of positive Gene Xpert results than MPT64-positive patients (73.8% vs 95.1%, P < 0.001). Several gene mutations were detected in the MPT64-negative MTB strains, including 63 bp deletion, single nucleotide mutations, and IS6110 insertion. Among 7,324 MTB genomes from the NCBI database, 87 strains had mutations in the mpt64 gene sequence, with four common mutation sites causing single amino acid changes, including G34A (8.0%), A103G (27.6%), T128A (9.2%), and C477A (24.1%).
Conclusion: A negative MPT64 antigen result in MTB cultures can be attributed to mutations in the mpt64 gene, and infections caused by these strains are more likely to be misdiagnosed.
期刊介绍:
Frontiers in Medicine publishes rigorously peer-reviewed research linking basic research to clinical practice and patient care, as well as translating scientific advances into new therapies and diagnostic tools. Led by an outstanding Editorial Board of international experts, this multidisciplinary open-access journal is at the forefront of disseminating and communicating scientific knowledge and impactful discoveries to researchers, academics, clinicians and the public worldwide.
In addition to papers that provide a link between basic research and clinical practice, a particular emphasis is given to studies that are directly relevant to patient care. In this spirit, the journal publishes the latest research results and medical knowledge that facilitate the translation of scientific advances into new therapies or diagnostic tools. The full listing of the Specialty Sections represented by Frontiers in Medicine is as listed below. As well as the established medical disciplines, Frontiers in Medicine is launching new sections that together will facilitate
- the use of patient-reported outcomes under real world conditions
- the exploitation of big data and the use of novel information and communication tools in the assessment of new medicines
- the scientific bases for guidelines and decisions from regulatory authorities
- access to medicinal products and medical devices worldwide
- addressing the grand health challenges around the world