"how frequent is the cerbrospinal fluid pleocytosis in infants with febrile seizures?"

febrile seizure is the most common type of convulsion yet described in man. it is a convulsive event mainly occurring in children between the ages of 6 to 60 months and is not accompanied by any type of electrolyte imbalance and cns infections, which are very difficult to be ruled out in infancy. to determine the frequency of cerebrospinal fluid (csf) pleocytosis in infants under the age of eighteen months with febrile seizure who routinely undergo lumbar puncture, we studied 159 cases (from 3 to 18 months of age, mean of 11, sd of 4 months), referred to takhti children hospital from september 1995 to september 1996 because of febrile seizures. there were only 5 patients (3.1%) with pleocytosis in our case series. significant correlation was found between pleocytosis and high erythrocyte sedimentation rates (ci=99%, chi square=5.94) in our patients. there was also a positive correlation between pleocytosis and the duration between the beginning of fever and occurrence of seizure (ci=98%, chi square=7.58). we concluded that there was little risk for our patients to have csf pleocytosis. we also strongly recommend further investigations to exam the relationship of various signs and symptoms with meningitis in infants with seizure and fever, preferably in the form of likelihood ratios. it is noteworthy to emphasize that performing a lumbar puncture in any infant less than 18 months of age is practically rational until more precise and specific indications emerge from further such welldesigned studies in the future.