Specific detection of Coxsackie viruses A by the polymerase chain reaction

Background: Most of the Coxsackie virus A strains are difficult to identify using traditional diagnostic methods such as virus isolation followed by neutralization with type-specific antisera. For the laboratory diagnoses of infections with Coxsackie viruses A, inoculation into newborn mice has traditionally been the method of choice. However, such investigations are complicated and time-consuming. Objectives: To develop a reverse transcriptase (RT) and polymerase chain reaction (PCR) assay for specific detection of Coxsackie viruses A. Study design: A total of 43 clinical specimens containing Coxsackie viruses A, B or echoviruses were investigated retrospectively. Nineteen samples were Coxsackie virus A positive, whereas 24 samples were positive for Coxsackie viruses B or echoviruses. Thirteen non-typable specimens from eight patients were also included, since they were characterized as enterovirus-like by electron microscopy. Results: All the specimens containing Coxsackie virus A were positive with the Coxsackie virus A PCR assay. In addition, five out of eight samples characterized as enterovirus-like by electron microscopy were PCR positive. The PCR assay did not amplify Coxsackie viruses B or echoviruses identified in our laboratory. Conclusion: The RT-PCR protocol established here should provide a useful alternative to the complicated and time-consuming diagnostic method based on live animals.