In empiric meningitis therapy, when should ampicillin be added?

• A. Young healthy adults
• B. Older adults or immunocompromised
• C. Never
• D. Only in neonates

Answer: (B)

Ampicillin is added to empiric meningitis therapy to cover Listeria monocytogenes, a pathogen that is more likely in older adults and in people who are immunocompromised. Cephalosporins alone don’t reliably cover Listeria, so in these at‑risk groups the regimen includes ampicillin in addition to the usual vancomycin and a third‑generation cephalosporin. In contrast, young healthy adults have a low risk of Listeria, so ampicillin isn’t routinely needed for them. Neonates also require ampicillin as part of their empiric therapy, but that doesn’t mean it’s limited to neonates alone.