Analysis of the results of routine lumbar puncture after a first febrile convulsion in Hofuf, Al-Hassa, Saudi Arabia.

Cerebrospinal fluid (CSF) was analysed to determine a lumbar puncture (LP) yield for meningitis in 95 children who presented with their first febrile convulsions between July 1993 and June 1994. There were 52 males and 43 females aged six months to six years with a mean age of 21.9 +/- 13.0 months at presentation. 87(91.6%) had simple febrile convulsions (SFC) while the remaining 8(8.4%) had complex febrile convulsions (CFC). The majority of the subjects presented with a sudden onset of convulsions that were preceded by a day or two history of fever, coryza, cough and respiratory distress while others had their convulsions preceded by fever and passage of bloody stools. The LP yield for meningitis in this series was 6.3%. The CSF analysis revealed six cases of meningitis comprising an eight month old infant with Haemophilus influenzae type B (HIB) meningitis, two partially treated pyogenic meningitis and three aseptic meningitis. All of them had presented with febrile convulsions without signs of meningeal irritation. Excluding aseptic meningitis from this series, a 3.1% LP yield for pyogenic meningitis is significant enough to recommend continued performance of LP in children with first febrile convulsions, especially if under the age of eighteen months.