Clinical utility of the polymerase chain reaction for diagnosis of enteroviral meningitis in infancy

Objective: To determine the utility of polymerase chain reaction (PCR) assay of cerebrospinal fluid (CSF), serum, and urine for rapid diagnosis of enteroviral meningitis in infants 3 months of age and younger. Study design: We identified prospectively infants 3 months of age and younger coming to the emergency department with fever whose examination included a lumbar puncture, blood culture, or both. Samples of CSF, serum, urine, throat, and stool specimens were collected for vital culture and, with the exception of stool, for PCR assay. Those infants who had not received prior antibiotic therapy and had sterile bacterial cultures of CSF, blood, and urine were selected for the present analysis. Results: A total of 259 specimens for viral culture and 203 specimens for PCR assay were collected from 64 infants. Comparison of results of PCR assay of CSF with viral culture, the gold standard for diagnosis of enteroviral meningitis, demonstrated a sensitivity of 100% and a specificity of 90%. Because enteroviruses are not always detectable by culture, the following modified standard was established to define enteroviral meningitis: either CSF pleocytosis, sterile bacterial cultures and detection of an enterovirus in stool culture or positive vital culture of CSF, or both. With this modified definition, the sensitivity and specificity of the PCR assay of CSF were 92% and 94%, respectively. PCR assay of serum and urine offered no benefit over PCR assay of CSF alone for diagnosis of meningitis. Conclusion: PCR assay of CSF is useful for the rapid and reliable diagnosis of enteroviral meningitis. Application of this technique in the clinical setting can potentially diminish unnecessary hospitalization and use of antibiotics.