A 2-month-old infant has a single febrile seizure with fever 39.6 C and bulging tympanic membrane. The next most appropriate step is to:

• A. Perform a Lumbar Puncture
• B. Order X-ray Studies of the Skull
• C. Obtain an Electroencephalogram
• D. Send Home with Antibiotics and an Anticonvulsant

Answer: (A)

In a 2-month-old with fever and a seizure, ruling out meningitis is essential because infants can present with nonspecific signs and serious CNS infections can progress quickly. A lumbar puncture provides direct analysis of the CSF to detect meningitis (through cell count, glucose, protein, culture, and Gram stain) and guides immediate treatment. The bulging tympanic membrane indicates otitis media but does not exclude meningitis, so relying on an ear infection alone isn’t enough. Imaging the skull, doing an electroencephalogram, or sending the child home with antibiotics and an anticonvulsant wouldn’t adequately evaluate for meningitis or ensure safe management. Perform LP to determine if meningitis is present and tailor therapy accordingly.