Key Points
- Stabilize ABCs; begin targeted evaluation without delaying life-saving therapy.
- Use system-specific risk tools to guide testing and disposition.
- Order high-yield tests first; escalate imaging when indicated.
- Start evidence-based initial therapy and reassess frequently.
Algorithm
- Primary survey and vitals; IV access and monitors.
- Focused history/physical; identify red flags and likely etiologies.
- Order system-appropriate labs and imaging (see Investigations).
- Initiate guideline-based empiric therapy (see Pharmacology).
- Reassess response; arrange consultation and definitive management.
Clinical Synopsis & Reasoning
Suspect bacterial meningitis in acute febrile encephalopathy with meningeal signs or unexplained sepsis; do not delay therapy for diagnostics in unstable patients. Check glucose and electrolytes, obtain blood cultures, and perform head CT prior to LP only with focal deficits, seizures, immunocompromise, or altered consciousness suggesting mass effect. CSF analysis (cell count, glucose, protein, Gram stain, PCR) directs pathogen‑specific management.
Treatment Strategy & Disposition
Give empiric, age‑adjusted IV antibiotics and dexamethasone when pneumococcal disease is suspected, ideally before or with the first antibiotic dose. Tailor coverage as culture/PCR results return, manage complications (seizures, raised ICP), and implement droplet precautions for meningococcal disease. Admit to ICU when neurologic monitoring, airway protection, or vasopressors are required; arrange prophylaxis for close contacts when indicated.
Epidemiology / Risk Factors
- Hypertension, AF, atherosclerosis; prior stroke/TIA
Investigations
| Test | Role / Rationale | Typical Findings | Notes |
|---|---|---|---|
| CT Head (NC) | Hemorrhage exclusion | Acute blood | First-line |
| Glucose (POC) | Exclude hypoglycemia | Low | Treat promptly |
| MRI Brain (selected) | Ischemia/structural | Diffusion restriction |
Empiric Therapy (Adults)
| Scenario | Regimen |
|---|---|
| 18–50 y, community-acquired | Ceftriaxone (or cefotaxime) + vancomycin |
| >50 y or immunocompromised | Ceftriaxone + vancomycin + ampicillin |
| Severe beta-lactam allergy | Moxifloxacin + vancomycin ± TMP-SMX for Listeria |
Pharmacology
| Medication | Mechanism | Onset | Role in Therapy | Limitations |
|---|---|---|---|---|
| Ceftriaxone + vancomycin | β-lactam + glycopeptide | Hours | Empiric adult therapy | Allergy; nephrotoxicity (vanc) |
| Ampicillin (add >50 or immunocompromised) | β-lactam | Hours | Listeria coverage | Allergy |
| Dexamethasone | Glucocorticoid | Hours | Adjunct for S. pneumoniae | Hyperglycemia |
Prognosis / Complications
- Outcome tied to time-to-reperfusion; aspiration/DVT risks
Patient Education / Counseling
- Explain red flags and when to seek emergent care.
- Reinforce medication adherence and follow-up plan.
Notes
Prophylaxis for close contacts in N. meningitidis (rifampin, ciprofloxacin, or ceftriaxone). Continue dexamethasone if S. pneumoniae confirmed.