人副肠孤病毒与儿童脓毒症和中枢神经系统感染的相关性

Human parechovirus associated sepsis and central nervous system infections in hospitalized children

目的 了解疑似中枢神经系统（CNS）感染患儿中人副肠孤病毒（HPeV）的感染状况及脓毒症感染的关系.方法 回顾性收集2012年因疑似CNS感染而在首都儿科研究所附属儿童医院住院患儿的脑脊液标本.采用针对HPeV基因组相对保守的5＇端非编码区和变异显著的衣壳蛋白基因3和1交界区的通用引物和分型引物,分别对脑脊液标本核酸进行反转录巢式PCR （RT-nPCR）扩增.阳性标本的PCR产物直接进行核苷酸序列测定,与GenBank中的序列进行比对分析并建立系统进化树.对HPeV筛查阳性的脑脊液标本进行肠道病毒（EV）、EB病毒（EBV）和人巨细胞病毒（HCMV）的检测.同时收集HPeV筛查阳性患儿的其他类型标本（包括血清、鼻咽洗液、粪便标本等）进行上述检测.结果 577份脑脊液标本中检测到18份HPeV阳性标本,检出率为3.1％.阳性患儿中男12例,女6例,年龄范围为15 d～14岁,其中3个月以下患儿最多,占7例;其次是3个月～1岁年龄组5例;另有3例阳性患儿＞9岁.对分型成功的10份脑脊液标本中HPeV的序列分析显示7份为HPeV 3型,3份为HPeV 1型.18份HPeV筛查阳性的脑脊液标本中EV、EBV和HCMV检测均为阴性.脑脊液HPeV筛查阳性患儿的其他类型标本中,8份血清标本中检出2份阳性（均为HPeV3）,其中1份与脑脊液标本检出及分型结果一致,而另1份对应脑脊液标本筛查为阳性,但未分出型别;2份粪便标本中检出1份阳性（HPeV1）,但对应脑脊液标本未分出型别.HPeV阳性患儿临床诊断主要是脓毒症（7/18）和CNS感染（4/18）.其中6例（6/8） HPeV3阳性患儿诊断为脓毒症.HPeV3感染多集中于8月份,而HPeV1则集中于1月份.结论 HPeV与北京儿童脓毒症和CNS感染性疾病相关.1岁以下儿童为易感人群.HPeV3型为脑脊液中主要的检出型别.

Objective Human parechovirus （HPeV） is a single-stranded,positive sense RNA virus in the Parechovirus genus within the large family of Picornaviridae.As a possible new pathogen of neonatal sepsis,meningoencephalitis and other infections in young children,HPeV gets more and more attention.This study aimed to better understand the association of HPeV with central nervous system （CNS） infectious diseases and sepsis among hospitalized children in Beijing.Method A total of 577 cerebrospinal fluid （CSF） samples were retrospectively collected from 557 children suspected of CNS infections in 2012.Three hundred and fifty-one of them were male and 206 were female.HPeV was screened by reverse transcription-nested PCR （RT-nPCR） with the universal primers which target the highly conserved 5＇UTR.The positive samples were genotyped by amplifying and sequencing for the VP3/VP1 junction region.The sequences were compared with the HPeV sequences from GenBank and performed phylogenetic analysis.Some samples other than CSF from HPeV positive children,including serum,nasopharyngeal aspirate and stool,were collected and carried out screening for HPeV.Result With the RT-nPCR by universal primers,HPeVs were detected in 18 out of 577 CSF samples obtained from 18 children with a positive rate of 3.1%.The ratio of male and female was 2 ∶ 1.There were no statistically significant differences on infection rate between boys （12/351,3.4%） and girls （6/206,2.9%）.All of 18 positive CSF samples were negative for enterovirus,Epstein-Barr virus （EBV）,human cytomegalovirus （HCMV）,and herpes simplex virus 1 and 2 （HSV）.HPeVs from 10 positive CSF samples were genotyped successfully,consisting of 7 HPeV3 and 3 HPeV1.In addition,2 of 8 serum samples were positive for HPeV3 and 1 of 2 stool samples were positive for HPeV 1.HPeVs were identified in CSF from children aged from 15 days to 14 years,in which 7 cases were infants younger than 3 months and 5 cases were infants from 3 months to one year.Three children older than the age of 9 years （9,13 and 14 years） were positive for HPeV.Most of the children （6/8） infected with HPeV3 were younger than 3 months and were diagnosed as sepsis,while the rest of HPeV3 positive children were diagnosed as meningitis and bronchopneumonia.HPeV3 infection clustered in August,while HPeV1 in January.Conclusion HPeVs were associated with CNS infections and sepsis in hospitalized children in Beijing,especially in children younger than one year.HPeV3 was the predominant type identified in CSF.