Significance of neutrophils in cerebrospinal fluid samples processed by cytocentrifugation

We reviewed medical records of 155 pediatric patients whose cerebrospinal fluid (CSF) samples contained an increased proportion of neutrophils when processed by cytocentrifugation, despite normal CSF total white blood cell count. It was determined that these CSF findings occurred more commonly in patients with bacteremia, peripheral leukocytosis, and increased numbers of red blood cells in the CSF. Pulmonary infiltrates in infants and otitis media in children were also significantly associated. Cytocentrifugation allows the identification of neutrophils in the CSF, even in the absence of central nervous system infection. Infants and children with more than 10 per cent neutrophils in CSF require evaluations for focal and bacteremic infections.