Antimicrobial Resistance and Microbiological Gap Analysis for Central Nervous System Infections Bacterial Pathogens in Nigeria

Background

Despite extensive vaccine efforts, central nervous system (CNS) infections remain a significant cause of morbidity and mortality in the African meningitis belt. This is increasingly complicated by the rising antimicrobial resistance (AMR) in pathogens not covered by the vaccine. We mapped pathogen-specific AMR profiles and diagnostic gaps in CNS bacterial pathogens to inform precision microbiological-based interventions for improved surveillance and empiric therapy in Nigeria.

Methods

We conducted a retrospective analysis of a three year national AMR surveillance data, focusing on CNS bacterial pathogens. Data from 25 sentinel laboratories were extracted, analysed and interpreted per CLSI/GLASS standards. AMR profiles and diagnostic gaps were assessed using descriptive statistics and Chi-square tests for demographic and temporal comparisons.

Results

Among all 84,548 valid cultures from over 26,000 patients, culture positivity rate was higher in females (35.1%) and older adults (>65 years, 40.0%, p < 0.001 ). CSF specimens were underrepresented, while species-level ambiguity was high for CNS-associated infections. Staphylococcus aureus , Escherichia coli and Klebsiella species were the dominant isolates, while Pseudomonas aeruginosa and Acinetobacter species showed persistent low-level presence. Alarmingly, Streptococcus pneumoniae showed rising penicillin resistance, reaching 100% by 2018. Other pathogens, including Klebsiella species , E. coli , and Pseudomonas aeruginosa showed high AMR across multiple drug classes. Gap analysis scored all CNS associated bacterial pathogens at maximum clinical risk (5/5), with major deficits in detection and the laboratory capacity. A precision-targeted recommendation map tailored microbiological interventions, such as neonatal AST protocol for E. coli and ICU infection registries for Pseudomonas species .

Conclusion

Species-level identification gaps and high AMR in CNS infections bacterial pathogens demand targeted microbiological-led diagnostics to include expanded CSF testing and AST-guided empiric therapy in resource-limited settings.

Highlights

• First national AMR gap analysis for CNS pathogens across 84,000 cultures in Nigeria

• Links resistance trends with diagnostic gaps for tailored stewardship interventions

• Introduces scalable microbiology-driven precision surveillance for LMIC settings

• Informs treatment protocols, lab policies and strategies for high-risk CNS infections