A 9-month-old infant treated with oral amoxicillin for 3 days for otitis media now has a brief generalized seizure with fever. He appears well afterwards with a normal neurological examination. According to standard guidance, lumbar puncture should be performed primarily because:

• A He is younger than 12 months of age
• B Otitis media always accompanies bacterial meningitis
• C Any seizure with fever requires CSF examination at any age
• D Prior antibiotic therapy can mask meningitis and produce misleading CSF findings ✓

Explanation

Guidelines recommend that LP be strongly considered in a child under 12 months with fever and seizure who has received prior antibiotics, because antibiotics partially treat meningitis, blunting clinical meningeal signs and altering CSF so it may appear aseptic despite bacterial infection. Age below 12 months alone is only a relative consideration when unimmunized or ill-appearing, and a well child returning to baseline without pretreatment does not require LP.

Reference: Nelson Textbook of Pediatrics, 21st ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.