宏基因组二代测序在恶性血液病并发感染患者中的诊断价值

目的:探讨宏基因组二代测序（mNGS）在恶性血液病并发感染患者中的诊断价值。方法:回顾分析2019年1月—2020年12月就诊于天津市第一中心医院血液科恶性血液病患者190例，对血浆mNGS检测到的致病菌种类、阳性率、检测时间及其与传统检测方法的结果进行分析。应用 SPSS22.0 统计学软件进行数据分析，通过Pearson χ2 检验或McNemar检验对离散变量进行比较分析。结果:血浆mNGS阳性率为77.37%，显著高于血培养（ χ2=13.36，P＜0.01）。细菌是mNGS检出率最高的病原体（43%），最常见的依次为葡萄球菌属、不动杆菌属和肠球菌属。mNGS所需要的时间少于血培养（t =22.37，P＜0.05）。此外，mNGS的敏感性较血培养高（80.25% vs. 8.02%， χ2=10.83，P＜0.01），但特异性低（47.06% vs. 100%， χ2=8.21，P＜0.01）。根据mNGS结果，75例（46.30%）患者调整抗感染治疗方案后，评价有效率为49.30%。结论:血浆mNGS联合传统的检测方法，能够快速且有效地提高对恶性血液病并发感染患者的病原学诊断能力，因而优化抗感染治疗。

Diagnostic value of plasma mNGS in patients with hematological malignancies complicated by infection

Objective: To explore the diagnostic value of metagenomic next-generation sequencing（mNGS）in patients with hematological malignancies complicated by infection. Methods:From January 2019 to December 2020，a total of 190 patients with hematological malignancies who were treated in the Department of Hematology，Tianjin First Central Hospital were retrospectively analyzed. The types of pathogenic bacteria detected by plasma mNGS，positive rate，detection time and the results compared with traditional detection methods were analyzed. SPSS22.0 statistical software was used for data analysis，and discrete variables were compared by Pearson χ2 test or McNemar test. Results:The positive rate of mNGS in plasma was 77.37%，which was significantly higher than that in blood culture（χ2=13.36，P＜0.01）. Bacteria were the pathogens with the highest detection rate in mNGS（43%），and the most common were Staphylococcus，Acinetobacter，and Enterococcus. The time required for mNGS was less than blood culture （t=22.37，P<0.05）. In addition，the sensitivity of mNGS was higher than that of blood culture（80.25% vs. 8.02%，χ2=10.83，P＜0.01），but the specificity was lower （47.06% vs. 100%，χ2=8.21，P＜0.01）. According to the mNGS results，after adjusting the anti-infective treatment regimen in 75 patients（46.30%），the effective rate was 49.3%. Conclusion:Plasma mNGS combined with traditional detection methods can rapidly and effectively improve the etiological diagnosis ability of patients with hematological malignancies complicated by infection，thus optimizing anti-infective treatment.