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Meningococcal Meningitis

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Meningococcal Meningitis, Neisseria Meningitidis, Meningococcus, Meningococcemia, Waterhouse-Friderichsen Syndrome

  • Epidemiology
  1. Most common in young adults and children with bimodal peak
    1. Age under 2 years accounts for 50% of cases
    2. Also peaks in teens
  2. Incidence
    1. Among top 2 causes of Bacterial Meningitis in U.S. (other is streptococcal Pneumoniae Meningitis)
    2. Up to 2800 cases per year per year in the U.S.
    3. One case per 100,000 people
  3. Exposure risks
    1. Sporadic cases are most common
    2. Outbreaks in close quarters (e.g. Dormitory)
  • Pathophysiology
  1. Neisseria Meningitidis is normal oral flora in 10%
  2. Transmission
    1. Respiratory secretions passed via aerosol or contact
  3. Serogroups (13): Disease caused by A, B, C, W-135, Y
  • Risk Factors
  1. Living in dormitory or military barracks
  2. More common in white males
  3. Tobacco use or passive Tobacco exposure
  4. Recent Upper Respiratory Infection
  • Precautions
  • Presentations may be cryptic
  1. Nuchal Rigidity may be absent
  2. Severe Upper Respiratory Infection may be only initial presentation
  3. Petechiae and fever confers a 10-15% risk of Meningococcemia
  4. May present with concurrent other infections (e.g. Otitis Media, Conjunctivitis, Pneumonia)
  • Symptoms
  • Signs
  1. See Meningitis
  2. Fever
  3. Nuchal Rigidity may be absent
  4. Rash (70% of cases)
    1. Centripetal Rash (starts on distal extremities, wrists and ankles)
    2. May start with light pink maculopapular rash (may even blanch initially)
    3. Petechiae (non-blanching) are common
    4. Fulminant Purpura (20% of cases)
      1. Central gun-metal gray center
  • Management
  1. See Bacterial Meningitis Management
  2. If considered, obtain Lumbar Puncture and start empiric antibiotics immediately
  3. Manage shock
    1. See Sepsis (covers fluid boluses and pressor use)
    2. Consider adding Corticosteroids to the antibiotic regimen
      1. Meningococcus may be associated with adrenal infarction Hemorrhage
  • Complications
  1. Waterhouse-Friderichsen Syndrome
    1. Shock, Petechiae and adrenal infarction (bilateral adrenal Hemorrhage)
  • Prevention
  1. See Meningococcal Vaccine
  2. Vaccination does on confer 100% protection (misses some sub-groups)
    1. Known exposures to Meningococcal Meningitis need antibiotic prophylaxis despite Immunization
  1. Indications
    1. Exposure from 7 days before onset of illness until 24 hours after antibiotics initiated AND
    2. Significant exposure (treat if any concern)
      1. Household contacts (up to 800 fold increase in risk, up to 1 in 250 will be infected)
      2. Child care centers
      3. Oral secretion exposure (e.g. health care worker without adequate protection)
      4. Long-distance (>8 hours) travel next to source
  2. Prophylaxis options (pick one): Start as soon as possible (up to 14 days after exposure)
    1. Rifampin
      1. Age <1 month: 5 mg/kg orally every 12 hours for 2 days
      2. Age >1 month: 10 mg/kg (max: 600) orally every 12 hours for 2 days
      3. Adults: 600 mg orally every 12 hours for 2 days
    2. Ciprofloxacin (adults) 500 mg orally for one dose
    3. Ceftriaxone (Rocephin)
      1. Age <15 years: 125 mg IM for one dose
      2. Age >15 years: 250 mg IM for one dose
  3. References
    1. Bilukha (2005) MMWR Recomm Rep 54:1-21 [PubMed]
  • Prognosis
  1. Mortality: Approaches 14% despite treatment
  2. Serious residual morbidity approaches 19%
  • References
  1. Claudius in Majoewsky (2012) EM:Rap 12(11): 8
  2. Kimmel (2005) Am Fam Physician 72:2049-56 [PubMed]