CSF findings in neonates with seizures; infectious and noninfectious

In order to evaluate parameters of cerebrospinal fluid (CSF) we studied 105 CSF samples of 50 neonates with seizures of unknown origin for cell count and chemistry (protein, albumin, glucose, IgG-index and albumin-ratio). Viral studies for 13 different microbes were performed from serum and CSF. CSF parameters of the babies with a suggested viral infection (n = 13) were compared with those without any viral findings (n = 37), and followed up to the age 45 weeks since conception. CSF mononuclear white blood cell count was < or = 20 x 10(6)/l at the age of < or = 40 weeks since conception, and thereafter i.e. at term it was < or = 10 x 10(6)/l in all neonates without viral infection, whereas mononuclear cell count was above these limits in 8 of 13 neonates with viral infection. The rate of IgG-index remained high only in the neonates with a viral infection when studied at the age of over 43 weeks since conception. We conclude that studies of CSF are a valuable diagnostic aid in CNS viral infections of neonates when evaluated in reference to the age since conception, and the limits of mononuclear white blood cells in normal CSF of neonates are in lower limits than reported before.