Meningococcal Septic Shock

Meningococcal septic shock is fulminant bloodstream infection with Neisseria meningitidis causing circulatory collapse, purpura, disseminated intravascular coagulation and multi-organ failure, with or without meningitis. Death can occur within hours.

Epidemiology. Peaks occur in infants, adolescents and young adults. Serogroups B, C, W, Y and A cause most disease, with serogroup A and W epidemics in the African meningitis belt. Case fatality for septicaemia is about 10 to 20% with treatment and is higher in shock.

Risk factors. Complement deficiency (terminal components, properdin), asplenia, HIV, eculizumab or ravulizumab treatment, close contact with a case, crowded settings (students, military recruits), smoking and recent viral infection.

Pathophysiology. Endotoxin (lipo oligosaccharide) and high bacterial load trigger severe inflammation, endothelial injury, capillary leak and DIC with microvascular thrombosis. Myocardial depression and adrenal injury are common.

Presentation is fever, limb pain, cold hands and feet, leg pain, abnormal skin colour (mottling), rapid progression to a non-blanching petechial or purpuric rash, tachycardia, hypotension, tachypnoea, confusion and oliguria. Early signs can be non-specific, with a blanching rash at first. Meningism is often absent in septicaemia.

Red flags.

• Non-blanching rash with fever, in any age.
• Cold extremities, mottled skin, leg pain and delayed capillary refill (over 2 seconds).
• Altered consciousness, hypotension or rapidly spreading purpura.

Never delay antibiotics for tests. Take blood cultures, but also nucleic acid amplification testing on blood (and CSF), full blood count, coagulation, fibrinogen, lactate, glucose, electrolytes, creatinine, liver tests and C-reactive protein. Lumbar puncture is contraindicated with shock, coagulopathy, rash with deterioration or raised intracranial pressure signs. Skin lesion scraping or aspirate Gram stain.

Differential diagnosis. Other septic shock, toxic shock syndrome, Rocky Mountain spotted fever, dengue, viral haemorrhagic fevers, Henoch-Schonlein purpura, immune thrombocytopenia and leukaemia.

Antibiotics within 1 hour. Ceftriaxone 2 g IV every 12 hours (adults; 4 g daily is used for meningitis), children 80 mg/kg once daily (maximum 4 g), or cefotaxime 2 g IV every 6 hours. If cephalosporins cannot be given (severe allergy), chloramphenicol or meropenem 2 g IV every 8 hours. Give benzylpenicillin 1.2 g IV or IM (adult) before hospital arrival. Total duration 5 to 7 days for septicaemia, and 7 days for meningitis.

Fluid and shock. Isotonic crystalloid boluses 20 mL/kg (500 mL in adults), repeated up to 40 to 60 mL/kg or more, with reassessment after each. Start noradrenaline or adrenaline early (0.05 to 1 microgram/kg/min) for fluid refractory shock, and intubate and ventilate early.

Corticosteroid. Dexamethasone 10 mg IV every 6 hours for 4 days (given before or with the first antibiotic dose) when meningitis is present. Hydrocortisone 50 mg IV every 6 hours for refractory shock or suspected adrenal injury.

Correct metabolic problems. Glucose, calcium, potassium, magnesium, phosphate and acidosis.

Coagulopathy. Fresh frozen plasma 10 to 15 mL/kg, cryoprecipitate and platelets for bleeding or procedures. Consider protein C concentrate (specialist) for purpura fulminans.

Limb threat. Monitor perfusion, fasciotomy for compartment syndrome and delayed surgery for necrosis.

Public health. Notify at once. Isolate with droplet precautions for 24 hours after effective antibiotics. Give chemoprophylaxis to close contacts within 24 hours: ciprofloxacin 500 mg orally once (adults), rifampicin 600 mg orally every 12 hours for 2 days (adults; 10 mg/kg for children over 1 month, 5 mg/kg for infants), or ceftriaxone 250 mg IM once (125 mg under 12 years, preferred in pregnancy). Offer vaccination as directed by public health.

Monitoring. Haemodynamics, lactate, urine output, coagulation, glucose, perfusion of limbs and neurological state.

Referral and escalation. Paediatric or adult intensive care, and retrieval team involvement early. Infection specialists and public health.

Special groups. In pregnancy, ceftriaxone is used, and ciprofloxacin is avoided for prophylaxis. In complement deficiency or asplenia, vaccinate and consider long term penicillin.