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

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.

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.

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.

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.