Limitations of polymerase chain reaction testing for diagnosing acute Epstein-Barr virus infections

Clinicians use molecular tests to detect Herpesviridae from blood without fully appreciating limitations of testing. Studies are needed to enhance our understanding of the impact of Herpesviridae latency on molecular testing. We retrospectively performed quantitative Epstein-Barr virus (EBV) on sera from patients between the ages of 1 and 30 who demonstrated serologic evidence of acute EBV (n = 50) or remote EBV (n = 50) infection. Epstein-Barr virus DNA was detected in 70% of acutely infected and 4% of remotely infected patients. Sera from acutely infected patients had higher EBV copy number than convalescent sera. Our results suggest that serology should be performed as the initial diagnostic test for acute EBV. The role for polymerase chain reaction in immunocompromised patients with impaired antibody responses or as a 2nd-line diagnostic test when serologic results are equivocal deserves further study.     

2016-2020年杭州地区单中心EB病毒感染患儿阳性检出率的统计与分析

目的 回顾性分析杭州地区2016年至2020年间儿童EB病毒的感染情况、构成、流行趋势等信息。方法 选取2016年至2020年期间,杭州市儿童医院病原体核酸检测的样本共72526例,将其中EB病毒核酸阳性的1391例纳入统计研究,并分析各年份杭州地区儿童EB病毒感染的人数、感染月份、性别比例及年龄构成等因素。结果 2016-2020年,报告EB病毒核酸阳性检出病例1391例,占全院儿童检测病原体包括肺炎支原体,沙眼支原体,解脲支原体,EBV和人巨细胞病毒等各类DNA病毒的1.92%,五年间EB病毒核酸阳性检出率分别为1.56%,1.81%,1.89%,1.63%和3.11%;性别方面,男性感染患儿的核酸阳性检出778例,女性感染核酸阳性检出613例,男女比例为1.27：1;年龄分布方面,1-6学龄前儿童EB病毒感染患儿核酸阳性检出1184例,占我院1-15岁患儿总检出病例数的85.12%。流行季节方面,夏秋季为感染高峰,冬春季不明显。结论 2016年-2019年,杭州地区EB病毒感染患儿比例相对平稳（x2趋势检验,P>0.05）,但在2020年,阳性检出率明显上升,这可能与新冠疫情有关;学龄前儿童为EB病毒的主要易感者,这与学龄前儿童的免疫水平以及淋巴细胞比例水平可能存在一定相关性,同时男童与女童的阳性检出率存在显著差异（P<0.05）且男童易感率更高,此外EB病毒传播还具有一定季节规律。     

血清学指标CK19-2G2、CyFra21-1及EBVVCA-IgA/EA-IgA与鼻咽鳞癌诊断和近期疗效的价值分析

目的观察鼻咽癌患者血清中细胞角蛋白片段CK19-2G2、CyFra21-1浓度及EB病毒抗体VCA-IgA、EA-IgA滴度水平,评价以上四项肿瘤标志物对鼻咽癌诊断和预后的应用价值。方法分别检测72例正常健康人和47例放疗前后的未分化型非角化性鼻咽癌患者血清CK19-2G2、CyFra21-1浓度和VCA-IgA/EA-IgA滴度,CK19-2G2应用北京同生时代公司的仪器及试剂盒(化学发光法)检测;CyFra21-1应用罗氏电化学发光法检测;VCA-IgA应用免疫酶法检测。结果未分化型非角化性鼻咽癌患者血清CK19-2G2、CyFra21-1和VCA-IgA/EA-IgA的阳性率分别为:32.69%、46.15%、98.08%和71.15%,健康人群以上四项指标的阳性率分别为:9.32%、9.72%、16.67%和0,P<0.01;与病理诊断的一致性检验显示以上四项指标的Kappa值分别为:0.355、0.418、0.78和0.76;四项指标与临床分期有统计学意义(χ2分别为:69.04、28.21、90.36和70.49,P<0.01);未分化型鼻咽鳞癌患者放疗前后CK19-2G2和CyFra21-1阳性率呈下降趋势。结论血清CK19-2G2、CyFra21-1水平在鼻咽鳞癌患者和健康人群中有显著性差异,EBV VCA-IgA/EA-IgA滴度检测对鼻咽癌的诊断有较高准确率;鼻咽鳞癌患者血清CK19-2G2、CyFra21-1水平与病理分期相关;血清CK19-2G2、CyFra21-1的水平可能对鼻咽鳞癌患者的预后评价有一定的价值。     

Comprehensive Evolutionary Analysis of Complete Epstein–Barr Virus Genomes from Argentina and Other Geographies

The sequence variability of the Epstein–Barr virus has been extensively studied throughout previous years in isolates from various geographic regions and consequent variations at both genetic and genomic levels have been described. However, isolates from South America were underrepresented in these studies. Here, we sequenced 15 complete EBV genomes that we analyzed together with publicly available raw NGS data for 199 EBV isolates from other parts of the globe by means of a custom-built bioinformatic pipeline. The phylogenetic relations of the genomes, the geographic structure and variability of the data set, and the evolution rates for the whole genome and each gene were assessed. The present work contributes to overcoming the scarcity of complete EBV genomes from South America and is the most comprehensive geography-related variability study, which involved determining the actual contribution of each EBV gene to the geographic segregation of the entire genome. Moreover, to the best of our knowledge, we established for the first time the evolution rate for the entire EBV genome based on a host–virus codivergence-independent assumption and assessed their evolution rates on a gene-by-gene basis, which were related to the encoded protein function. Considering the evolution of dsDNA viruses with a codivergence-independent approach may lay the basis for future research on EBV evolution. The exhaustive bioinformatic analysis performed on this new dataset allowed us to draw a novel set of conclusions regarding the genome evolution of EBV.