If a patient is less than one month old or over 60 years old, which antibiotic is added for meningitis treatment?

In cases of meningitis, particularly in very young infants (less than one month old) and in elderly patients (over 60 years old), the choice of antibiotics must account for specific pathogens that are more likely to cause infection in these age groups.

Ampicillin is the appropriate choice in this scenario because it effectively covers Listeria monocytogenes, which is a common concern in both neonates and older adults. In infants, the most prevalent pathogens include Group B Streptococcus, Escherichia coli, and Listeria, the latter being particularly pertinent since it can cause severe meningitis in both populations mentioned.

In the context of treating meningitis, adding ampicillin to cover for Listeria is critical, especially in age groups that have heightened vulnerability to this pathogen. Thus, when initiating treatment, adding ampicillin ensures broader coverage and helps mitigate the risk of severe outcomes from missed infections involving Listeria.

Other antibiotics like vancomycin are important for covering resistant strains of Streptococcus pneumoniae or Staphylococcus aureus, but they don't specifically address the concern of Listeria. Cefepime and aztreonam have their roles in treating various infections but do not provide the necessary