Simultaneous recovery of bacterial and viral pathogens from cerebrospinal fluid

Mixed bacterial infection in meningitis is well-documented, but there have been few previous reports of mixed viral-bacterial meningitis. A retrospective analysis of the bacterial and viral cerebrospinal fluid (CSF) cultures from a 1-year period in a 315-bed children's hospital revealed 5 patients with mixed viral-bacterial meningitis among 276 patients with viral and/or bacterial culture-positive meningitis. These 5 accounted for 2.8% of the patients with positive CSF viral cultures and 4.8% of those with positive CSF bacterial cultures. All of the viruses were identified as enteroviruses, and the bacteria were Group B Streptococcus, Group D Salmonella, Streptococcus pneumoniae, Haemophilus influenzae type b and Staphylococcus aureus. The ages of the patients ranged from 10 days to 22 years. The clinical course of each of the illnesses was typical of bacterial meningitis. This relatively high frequency of mixed viral-bacterial meningitis could affect the utility of rapid viral diagnostic tests for CSF viruses.