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Post-neurosurgical meningitis; gram negative bacilli vs. gram positive cocci
Mehdi Zeinalizadeh1, Roya Yazdani2, Mohammad Mehdi Feizabadi3
1Department of Neurosurgery, Brain and Spinal Cord Injury Research Center, Imam Khomeini Hospital, Tehran University of Medical Sciences, Tehran, Iran.
Background:
Post-neurosurgical meningitis is a significant cause of mortality and morbidity. In this study we aimed to compare the differences of clinical, laboratory features and outcomes between the post-neurosurgical meningitis caused by gram-negative bacilli (GNB) and gram-positive cocci (GPC).
Methods:
Cases of post-neurosurgical meningitis (with positive CSF culture) were included. After classifying patients as GNB and GPC groups, clinical and paraclinical data were compared.
Results:
Out of 2667 neurosurgical patients, CSF culture was positive in 45 patients. 25 (54.3%) were GNB, 19 (41.3%) GPC. The most common microorganisms were Klebsiella pneumoniae (n=14, 31.1%), Coagulase negative staphylococcus (n=8, 17.8%), Staphylococcus aureus (n=6, 13.3%), Acinetobacter baumannii (n=4, 8.9%), Pseudomonas aeruginosa (n=2, 4.4%), and Escherichia coli (n=2, 4.4%). There were no correlation between CSF Leakage, Surgical site appearance, presence of drain, Age and GCS between two groups (P=0.11, P=0.28, P=0.06, P=0.86, P=0.11 respectively). The only different laboratory indexes were ESR (86.8 mm/h vs. 59.5 mm/h, P=0.01) and PCT (13.1 ng/ml vs. 0.8 ng/ml, P=0.02) which were higher in GNB cases. 20% (n=5) of patients with GNB meningitis received preoperative corticosteroid, while none of GPC cases received (P=0.03). The median length of hospitalization for GNB and GPC cases was 56 and 44.4 days respectively (P=0.3).
Conclusion:
The GNB antibiotic coverage should be designed more carefully in post-neurosurgical meningitis especially in patients with recent corticosteroid therapy and elevated ESR and procalcitonin.
Insights
Post-neurosurgical meningitis caused by gram-negative bacilli (GNB) presents with higher inflammatory markers like ESR and procalcitonin compared to gram-positive cocci (GPC). Careful antibiotic selection is crucial for GNB meningitis, particularly with corticosteroid use.
Area of Science:
- Infectious Diseases
- Neurosurgery
- Microbiology
Background:
- Post-neurosurgical meningitis is a serious complication following neurosurgery.
- It significantly contributes to patient mortality and morbidity.
- Understanding causative pathogens is key to effective treatment.
Purpose of the Study:
- To compare clinical, laboratory, and outcome differences.
- To differentiate post-neurosurgical meningitis caused by Gram-negative bacilli (GNB) versus Gram-positive cocci (GPC).
Main Methods:
- Retrospective analysis of 45 post-neurosurgical meningitis cases with positive CSF culture.
- Patients classified into GNB and GPC groups.
- Comparison of clinical data, laboratory indexes, and outcomes.
Main Results:
- Gram-negative bacilli (GNB) accounted for 54.3% of cases, with Klebsiella pneumoniae being most common.
- Elevated Erythrocyte Sedimentation Rate (ESR) and Procalcitonin (PCT) were observed in GNB meningitis.
- Preoperative corticosteroid use was more frequent in GNB cases (20% vs 0%).
Conclusions:
- Gram-negative bacilli (GNB) meningitis shows distinct laboratory findings, including higher ESR and PCT.
- Empirical antibiotic strategies for GNB meningitis require careful consideration.
- Elevated inflammatory markers and prior corticosteroid use may indicate GNB etiology.
