Introduction. Meningitis is the most important differential diagnosis in children with a febrile seizure, and lumbar puncture for cerebrospinal fluid (CSF) collection may be a necessary procedure for establishing a diagnosis. The objective of this study was to evaluate the profile of children with a febrile seizure submitted to CSF collection.

Methods. A cross-sectional, descriptive study in which the records of children of 6 months to 5 years of age presenting with a febrile seizure and submitted to CSF collection were analyzed.

Results. A total of 126 patients were included. In 72 children (57.14%), the seizure occurred in the first 24 hours of fever. Signs of meningeal irritation were rare, with neck stiffness being found in 4 patients (3.17%) and headache in 3 (2.38%).  CSF findings were normal in 128 children (99.21%) and only one patient presented with viral meningitis.

Discussion.In the present study, 77% of the patients had a simple febrile seizure.  CSF examination was normal in 99.20% of the patients, with results compatible with viral meningitis in only one child.

As shown in the literature, the risk of bacterial meningitis associated with a simple febrile seizure when clinical examination is normal is extremely low.  Therefore, lumbar puncture is of little use in these children.

Conclusion. These results emphasize that in children with a febrile seizure, clinical observation could reduce the practice of unnecessary lumbar puncture for CSF collection.