What is the appropriate management and treatment for a patient suspected of having meningitis, considering their immune status and past medical history?

Management of Suspected Meningitis

For any patient with suspected meningitis, immediately administer empiric antibiotics within 1 hour of hospital arrival—do not delay treatment for lumbar puncture or neuroimaging if these procedures cannot be completed promptly. 1, 2, 3

Immediate Actions (First Hour)

Stabilization and Assessment

• Stabilize airway, breathing, and circulation first, then document Glasgow Coma Scale (GCS) score to assess severity and guide subsequent decisions 2
• Obtain blood cultures within the first hour before antibiotics, but never delay antibiotic administration beyond 1 hour to obtain cultures 2, 3
• Assess for contraindications to immediate lumbar puncture including: focal neurological signs, papilledema, continuous/uncontrolled seizures, GCS ≤12, immunocompromised state, history of CNS disease, new seizure within 1 week, signs of severe sepsis/rapidly evolving rash, respiratory/cardiac compromise, coagulopathy, or infection at LP site 1, 2

Critical Care Involvement

• Involve intensive care teams immediately if the patient has: rapidly evolving rash, limb ischemia, cardiovascular instability, acid/base disturbance, hypoxia, respiratory compromise, frequent seizures, or altered mental state 1
• Transfer to ICU if: rapidly evolving rash present, GCS ≤12 (or drop >2 points), requiring monitoring/organ support, or uncontrolled seizures 1, 3
• Strongly consider intubation if GCS <12 1, 3

Empiric Antibiotic Therapy

Standard Regimen by Age and Risk Factors

Adults <60 years (immunocompetent):

• Ceftriaxone 2g IV every 12 hours OR Cefotaxime 2g IV every 6 hours 1, 3, 4
• Add Vancomycin 15-20 mg/kg IV every 8-12 hours if penicillin-resistant pneumococci suspected (recent travel to high-resistance areas) 1, 3

Adults ≥60 years OR immunocompromised:

• Ceftriaxone 2g IV every 12 hours OR Cefotaxime 2g IV every 6 hours 1, 3
• PLUS Amoxicillin 2g IV every 4 hours (for Listeria coverage) 1, 3
• PLUS Vancomycin 15-20 mg/kg IV every 8-12 hours if resistant pneumococci suspected 1, 3

Alternative for penicillin allergy:

• Chloramphenicol 25 mg/kg IV every 6 hours 1
• PLUS Co-trimoxazole 10-20 mg/kg (trimethoprim component) in four divided doses for patients ≥60 years 1

Geographic Considerations

• Check recent travel history (within 6 months) to countries with high pneumococcal resistance rates via European Centre for Disease Prevention and Control or WHO websites 1
• Add Vancomycin 15-20 mg/kg IV every 12 hours OR Rifampicin 600mg IV/PO every 12 hours if patient traveled to high-resistance areas 1, 3

Adjunctive Dexamethasone Therapy

Administer dexamethasone 10mg IV every 6 hours immediately before or simultaneously with first antibiotic dose 1, 3

Continuation Criteria:

• Continue for 4 days if pneumococcal meningitis confirmed or thought probable based on clinical, epidemiological, and CSF parameters 1, 3
• Stop dexamethasone if another cause of meningitis is confirmed or thought probable 1
• Can still initiate dexamethasone up to 12 hours after first antibiotic dose if not given initially 1

Lumbar Puncture Strategy

If NO Contraindications Present:

• Perform LP within 1 hour of hospital arrival after blood cultures obtained 2
• Send CSF for: cell count with differential, glucose, protein, Gram stain, bacterial culture 2, 3

If Contraindications Present:

• Start antibiotics immediately after blood cultures 2, 3
• Obtain urgent CT head to assess for mass effect, significant brain swelling, or midline shift 2
• Perform LP only if CT shows no contraindications to the procedure 3
• If LP performed after antibiotics started, do so within 4 hours of antibiotic initiation when possible to maximize diagnostic yield 1

Critical Pitfall to Avoid:

Never delay antibiotics beyond 1 hour waiting for neuroimaging or LP—delay in treatment is strongly associated with increased mortality and poor neurological outcomes 3, 5, 6

Definitive Therapy (Once Pathogen Identified)

Streptococcus pneumoniae (Pneumococcal Meningitis):

• Continue Ceftriaxone 2g IV every 12 hours OR Cefotaxime 2g IV every 6 hours 1
• If penicillin-sensitive (MIC ≤0.06 mg/L): Benzylpenicillin 2.4g IV every 4 hours is acceptable alternative 1
• If penicillin-resistant but cephalosporin-sensitive: Continue ceftriaxone/cefotaxime 1
• If both penicillin AND cephalosporin-resistant: Continue ceftriaxone/cefotaxime PLUS Vancomycin 15-20 mg/kg IV every 12 hours PLUS Rifampicin 600mg IV/PO every 12 hours 1
• Duration: 10 days if recovered by day 10; 14 days if not recovered or if resistant organism 1, 3
• Continue dexamethasone for full 4 days 1

Neisseria meningitidis (Meningococcal Meningitis):

• Continue Ceftriaxone 2g IV every 12 hours OR Cefotaxime 2g IV every 6 hours 1, 3
• Alternative: Benzylpenicillin 2.4g IV every 4 hours 1
• Add single dose Ciprofloxacin 500mg PO if patient not treated with ceftriaxone (for eradication) 1, 3
• Duration: 5 days if recovered by day 5 1, 3
• Stop dexamethasone once meningococcal etiology confirmed 1

Special Considerations

Neonates (≤28 days):

• Ceftriaxone is contraindicated in premature neonates and in neonates requiring calcium-containing IV solutions due to precipitation risk 4
• If ceftriaxone must be used, administer IV doses over 60 minutes to reduce risk of bilirubin encephalopathy 4
• Never use calcium-containing diluents (Ringer's solution, Hartmann's solution) with ceftriaxone 4

Immunocompromised Patients:

• Always add Listeria coverage with Amoxicillin 2g IV every 4 hours regardless of age 1, 3
• Risk factors for Listeria include: age >50 years, diabetes mellitus, immunosuppressive drugs, cancer, other immunocompromising conditions 3

Outpatient Parenteral Antibiotic Therapy (OPAT):

• Consider OPAT for patients who are: afebrile, clinically improving, able to take oral medications, have reliable IV access, willing to participate, and have no other acute medical needs 1, 3
• Regimen: Ceftriaxone 2g IV twice daily (can switch to once daily after first 24 hours) 1
• Add Rifampicin 600mg PO twice daily if penicillin-resistant pneumococci 1

Monitoring and Complications

Neurological Adverse Reactions:

• Discontinue ceftriaxone immediately if encephalopathy, seizures, myoclonus, or non-convulsive status epilepticus develop 4
• These reactions are reversible and resolve after discontinuation 4
• Make dosage adjustments in patients with severe renal impairment 4

Clostridium difficile-Associated Diarrhea:

• Consider CDAD in all patients who develop diarrhea during or after antibiotic treatment 4
• Discontinue ceftriaxone if CDAD suspected and not directed against C. difficile 4

Hemolytic Anemia:

• Monitor for immune-mediated hemolytic anemia during cephalosporin treatment 4
• Stop ceftriaxone if anemia develops until etiology determined 4

Therapies NOT Recommended

• Glycerol is NOT recommended as adjuvant therapy for community-acquired bacterial meningitis in adults 1
• Therapeutic hypothermia is NOT recommended for adults with bacterial meningitis 1
• Steroids should NOT be used for cerebral malaria (adverse effect on outcome) 7