Cerebrospinal fluid characteristics of PCR diagnosed enteroviral meningitis (EVM) in children

Distinguishing bacterial from viral meningitis helps prevent unnecessary use of antibiotics and decreases the length of stay.  The distinction may often be blurred by the typical textbook description of viral meningitis which states that mononuclear cells predominate in the cerebrospinal fluid (CSF). The aim of the work is to accurately describe the CSF response in a group of children with enteroviral meningitis proven by the gold standard, polymerase chain reaction (PCR).  A cross sectional study was performed at Sheikh Khalifa Medical City (SKMC), Abu Dhabi, United Arab Emirates (UAE).  We examined retrospectively all children (< 12 years as per hospital definition) who tested PCR positive for enterovirus in the CSF from January 2005 to January 2007. 53 patients with mean age (SD) of 74.8 months (37.8) were included.  There was a statistically significant dominance in polymorphnuclear cells (PMN) in both the CSF (Chi Square statistic 28.78, P < 0.001) and serum, which persisted after 24 h with mononuclear cells and PMN equally represented.  A correlation between CSF and serum PMN% was also detected (Pearson's r = 0.447, P=0.001, 95% CI = 0.196 to 0.643). Our peak season was in spring, there was a male predominance and the median (IQR) length of stay was 48 h (48 -72). The majority of children with aseptic meningitis had PMN predominance in both CSF and serum, which is not limited to the first 24 h. This finding differs from most standard textbook descriptions and may have relevance in using PMN counts to distinguish bacterial from viral meningitis.