摘要
Hand,foot and mouth disease(HFMD)is a major public health problem among children in the Asia-Pacific region.The optimal specimen for HFMD virological diagnosis remains unclear.Enterovirus A71(EV-A71)neutralizing antibody titres detected in paired sera were considered the reference standard for calculating the sensitivity,specificity,positive and negative predictive value of throat swabs,rectal swabs,stool,blood samples and cerebrospinal fluid(CSF)by RT-PCR or ELISA assay.In this study,clinical samples from 276 HFMD patients were collected for analysing the sensitivity of different kind of specimens.Our results showed that stool had the highest sensitivity(88%,95%CI:74%–96%)and agreement with the reference standard(91%).The order of diagnostic yield for EV-A71 infection was stool samplerectal swab>throat swab>blood sample>CSF sample,and using a combination of clinical samples improved sensitivity for enterovirus detection.The sensitivity of ELISA for IgM antibody detection in sterile-site specimens was significantly higher than that of RT-PCR(serum/plasma:62%vs.2%,CSF:47%vs.0%)(P<0.002).In conclusion,our results suggest that stool has the highest diagnostic yield for EV-A71-infected HFMD.If stool is unavailable,rectal swabs can be collected to achieve a similar diagnostic yield.Otherwise,throat swabs may be useful in detecting positive samples.Although IgM in blood or CSF is diagnostically accurate,it lacks sensitivity,missing 40%–50%of cases.The higher proportion of severe cases and shorter interval between onset and sampling contributed to the increase in congruency between clinical testing and the serological reference standard.
基金
supported by the National Natural Science Fund for Distinguished Young Scholars of China(No.81525023)
in whole or in part,by a Wellcome Trust fellowship awarded to LT[205228/Z/16/Z]
supported by the National Institute for Health Research Health Protection Research Unit in Emerging and Zoonotic Infections(grant no.NIHR200907)at University of Liverpool in partnership with Public Health England(PHE),in collaboration with Liverpool School of Tropical Medicine and the University of Oxford.LT is based at the University of Liverpool.