Treatment of Meningococcal Meningitis with Penicillin Resistance (Neisseria meningitidis MIC ≥0.1 μg/mL)

When Neisseria meningitidis demonstrates a penicillin minimum inhibitory concentration (MIC) of 0.1 μg/mL or higher, the organism is considered penicillin resistant. This finding has direct implications for antibiotic selection — standard penicillin-based therapy is no longer appropriate, and an alternative intravenous regimen is required.

This protocol is indicated when laboratory testing or local epidemiological data suggests that the causative N. meningitidis strain is unlikely to be susceptible to penicillin. Confirmed or suspected penicillin resistance requires prompt selection of an agent with demonstrated in vitro activity, ideally guided by susceptibility testing once available.

Management centres on intravenous administration of a third-generation cephalosporin as the primary approach. For situations where that option is not suitable, additional alternative agents are specified in the full protocol.

Complete antibiotic selection, specific agents, and all other regimen details are available in the structured protocol below.