What are the signs and treatment of meningitis?

Signs and Treatment of Meningitis

The classic signs of meningitis include fever, headache, neck stiffness, and altered mental status, though less than 50% of patients present with all these symptoms simultaneously, making rapid recognition and treatment with appropriate antibiotics essential to reduce mortality and morbidity. 1

Clinical Signs and Symptoms

Common Presenting Features

• Fever (present in 74-84% of cases) 1, 2
• Headache (present in 84% of cases) 2
• Neck stiffness (present in 74% of cases) 2
• Altered mental status (median Glasgow Coma Scale score of 11) 2
• Nausea (62% of cases) 2
• Vomiting 1
• Seizures 1
• Rash (particularly with meningococcal infection) 1

Important Clinical Considerations

• Up to 95% of patients will have at least two of the four cardinal symptoms: fever, nuchal rigidity, altered mental status, and headache 3
• The "classic triad" of neck stiffness, fever, and altered consciousness is present in less than 50% of cases 1
• Kernig's and Brudzinski's signs should not be relied upon for diagnosis due to low sensitivity (as low as 5%) despite high specificity (up to 95%) 1
• Elderly patients often present atypically with more altered mental status and less neck stiffness or fever 1

Meningococcal Sepsis Signs

• Purpuric rash (when present with meningitis, 92% of cases are caused by N. meningitidis) 1
• Signs of shock (hypotension, poor capillary refill) 1
• Limb ischemia 1
• Rapidly evolving rash 1

Diagnostic Approach

Initial Assessment

• Document presence or absence of headache, altered mental status, neck stiffness, fever, rash, seizures, and signs of shock 1
• Consider meningitis even when classic signs are absent, especially in elderly or immunocompromised patients 1
• All patients with suspected meningitis should be referred to hospital for evaluation and consideration of lumbar puncture 1

Diagnostic Testing

• Lumbar puncture is the gold standard for diagnosis 3
• Brain imaging (CT or MRI) before lumbar puncture is indicated in patients with:
  • Focal neurological deficits (excluding cranial nerve palsies)
  • New-onset seizures
  • Severely altered mental status (GCS <10)
  • Severely immunocompromised state 1
• If lumbar puncture is delayed, blood cultures should be obtained and empiric antibiotics started immediately 1

Treatment

Immediate Management

• Antibiotics should be started as soon as possible, ideally within 1 hour of clinical suspicion 1
• If lumbar puncture is delayed, empiric treatment must be started immediately upon clinical suspicion 1

Empiric Antibiotic Therapy

• Adults aged 18-50 years: Ceftriaxone or cefotaxime plus vancomycin or rifampicin 1
• Adults >50 years or immunocompromised: Ceftriaxone or cefotaxime plus vancomycin or rifampicin plus ampicillin/amoxicillin/penicillin G (to cover Listeria) 1
• Dosing:
  • Ceftriaxone: 2g q12h or 4g q24h 1, 4
  • Cefotaxime: 2g q4-6h 1, 5
  • Vancomycin: 10-20 mg/kg q8-12h (to achieve trough levels of 15-20 μg/mL) 1
  • Rifampicin: 300 mg q12h 1
  • Ampicillin: 2g q4h 1

Adjunctive Therapy

• Dexamethasone should be used in patients with bacterial meningitis but stopped if Listeria monocytogenes is confirmed 2
• Patients with severe sepsis should be managed in a critical care setting according to surviving sepsis guidelines 1

Critical Care Considerations

• Intensive care referral is indicated for patients with:
  • Rapidly evolving rash
  • GCS ≤12 (or drop >2 points)
  • Cardiovascular instability
  • Respiratory compromise
  • Frequent seizures
  • Altered mental state 1
• Intubation should be strongly considered for GCS <12 1
• Maintain euvolemia with crystalloids as initial fluid of choice 1
• Target mean arterial pressure ≥65 mmHg 1

Complications and Sequelae

Acute Complications

• Neurological deficits (occur in 50% of adults) 1
• Seizures 1
• Hydrocephalus 1
• Cerebrovascular complications (infarctions, hemorrhage, venous sinus thrombosis) 1
• Hemodynamic or respiratory insufficiency (occurs in 33% of patients) 1

Long-term Sequelae

• Hearing loss (occurs in 5-35% of patients) 1
• Cognitive deficits 1
• Seizures (13% of children) 1
• Motor deficits (12% of children) 1
• Visual disturbances 1

Follow-up Care

• All patients should be assessed for potential long-term sequelae before discharge 1
• Hearing tests should be performed if hearing loss is suspected, or if the patient lacks capacity to report hearing loss 1
• Hearing testing should occur before discharge or within 4 weeks 1
• Patients with severe to profound deafness should be offered fast-track assessment for cochlear implant 1
• Post-hospital follow-up should be offered to all patients with confirmed or probable bacterial meningitis 1

Prevention

• Chemoprophylaxis for close contacts of meningococcal meningitis patients 1
• Vaccination with pneumococcal vaccine for patients after pneumococcal meningitis and persons with CSF leakage 1

Common Pitfalls

• Relying on the presence of the classic triad for diagnosis (present in <50% of cases) 1
• Delaying antibiotic treatment while waiting for diagnostic confirmation 1
• Failing to recognize atypical presentations in elderly patients 1
• Overlooking the need for ampicillin in older adults to cover Listeria 1
• Neglecting to assess for hearing loss and other sequelae before discharge 1