Z Li1, L Pan1, L Lyu1, J Li2, H Jia1, B Du1, Q Sun1, Z Zhang3. 1. Beijing Key Laboratory for Drug Resistant Tuberculosis Research, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China. 2. People's Liberation Army 263 Hospital, Beijing, China. 3. Beijing Key Laboratory for Drug Resistant Tuberculosis Research, Beijing Chest Hospital, Capital Medical University, Beijing Tuberculosis and Thoracic Tumor Research Institute, Beijing, China. Electronic address: zzd417@ccmu.edu.cn.
Abstract
OBJECTIVES: Tuberculous meningitis (TBM) is difficult to diagnose. Digital PCR (dPCR) is a novel method which can quantify trace nucleic acids. This study sought to evaluate the diagnostic accuracy of dPCR analysis of cerebrospinal fluid (CSF) for TBM. METHODS: We collected CSF specimens from hospitalized TBM and non-TBM patients. Total CSF DNA was purified and the concentrations of Mycobacterium tuberculosis insert sequence 6110 (IS6110) and gyrase subunit B (gyrB) were quantified using droplet dPCR. The receiver operating characteristic curves of dPCR were established and the diagnostic performances were obtained. We also compared the sensitivity of dPCR with routine diagnostic tests. RESULTS: A total of 101 patients were recruited, 68 of whom suffered from TBM (26 definite, 34 probable and eight possible TBM) and 33 from non-TBM. The sensitivity of IS6110-dPCR assay for total TBM was higher than that of gyrB-dPCR assay (57.4% (44.8-69.3%) vs. 22.1% (12.9-33.8%)), and there was no significant difference for specificity between them (97.0% (84.2-99.9%) vs. 100% (89.4-100.0%)). The sensitivity of IS6110-dPCR in definite TBM was higher than that in probable and possible TBM (73.1% vs. 52.9% and 25.0%, respectively). IS6110-dPCR assay showed a higher sensitivity than smear microscopy (53.3% vs. 6.7%), mycobacterial culture (50.0% vs. 12.5%), IS6110-quantitative PCR (53.1% vs. 21.9%) and Xpert MTB/RIF (70.4% vs. 29.6%). Long anti-tuberculosis treatment time was found to be significantly associated with negative dPCR results. CONCLUSION: CSF IS6110-dPCR assay is a rapid and sensitive molecular test, which has the potential to be used to enhance the diagnosis of TBM.
OBJECTIVES:Tuberculous meningitis (TBM) is difficult to diagnose. Digital PCR (dPCR) is a novel method which can quantify trace nucleic acids. This study sought to evaluate the diagnostic accuracy of dPCR analysis of cerebrospinal fluid (CSF) for TBM. METHODS: We collected CSF specimens from hospitalized TBM and non-TBM patients. Total CSF DNA was purified and the concentrations of Mycobacterium tuberculosis insert sequence 6110 (IS6110) and gyrase subunit B (gyrB) were quantified using droplet dPCR. The receiver operating characteristic curves of dPCR were established and the diagnostic performances were obtained. We also compared the sensitivity of dPCR with routine diagnostic tests. RESULTS: A total of 101 patients were recruited, 68 of whom suffered from TBM (26 definite, 34 probable and eight possible TBM) and 33 from non-TBM. The sensitivity of IS6110-dPCR assay for total TBM was higher than that of gyrB-dPCR assay (57.4% (44.8-69.3%) vs. 22.1% (12.9-33.8%)), and there was no significant difference for specificity between them (97.0% (84.2-99.9%) vs. 100% (89.4-100.0%)). The sensitivity of IS6110-dPCR in definite TBM was higher than that in probable and possible TBM (73.1% vs. 52.9% and 25.0%, respectively). IS6110-dPCR assay showed a higher sensitivity than smear microscopy (53.3% vs. 6.7%), mycobacterial culture (50.0% vs. 12.5%), IS6110-quantitative PCR (53.1% vs. 21.9%) and Xpert MTB/RIF (70.4% vs. 29.6%). Long anti-tuberculosis treatment time was found to be significantly associated with negative dPCR results. CONCLUSION: CSF IS6110-dPCR assay is a rapid and sensitive molecular test, which has the potential to be used to enhance the diagnosis of TBM.
Authors: Yean K Yong; Hong Y Tan; Alireza Saeidi; Won F Wong; Ramachandran Vignesh; Vijayakumar Velu; Rajaraman Eri; Marie Larsson; Esaki M Shankar Journal: Front Microbiol Date: 2019-12-18 Impact factor: 5.640