[Role of lumbar puncture for febrile seizure among infants under one year old].

Background: Febrile seizure is a frequent cause of hospitalization. Its management remains problematic. According to the American Academy of Pediatrics, lumbar puncture, which is not devoid of risk, is strongly recommended in infants under 1 year.
Aim: to define the utility of lumbar puncture in the management of febrile seizures in infants under 12 months and to identify risk factors of meningitis and to respond to this question: "lumbar punction should be done in which infant with febrile seizure?"
Patients and Methods: This retrospective study was conducted in the department of pediatrics B in the Children Hospital of Tunis on eight-year period (2000-2008). In all statistical tests, significance level was set at 0.05.
Results: One hundred and six cases were collected during the period of study. Seizures related to bacterial meningitis were seen in 11 cases (10%). We have separated two groups: GI infants presented bacterial meningitis, and G2 infants with febrile seizure. The comparison between the two groups G1 and G2 showed the following predictors factors of meningitis: age < or = 7 months (p = 0.035), partial seizure (p = 0.028), duration of seizure > 5 min (p < 0.001), recurrence of seizure in the same day(p = 0,006), neurological abnormalities p < 0.001), CRP > 20 mg/l (p = 0.03), hyponatremia < or = 125 mmol/l (p = 0.01). The risk of meningitis is very low: 3.1 x 10 -3, if this condition is met: infants older than 7 months, having a unique and short seizure < or = 5 min, and with a CRP < or = 20mg/l.
Conclusion: If the infant is older than 7 months, presenting a unique, febrile and short (< or = 5 min) seizure, having a normal neurological examination with CRP < or = 20 mg/l, lumbar puncture should be discussed a case by case but an hospitalization for 24 hours is required for monitoring.