Meningitis and encephalitis

  • PIC logo
    PIC Endorsed
  • See also

    Fluid management in meningitis 
    Lumbar puncture 
    CSF interpretation

    Acute meningococcal disease 

    Febrile child 
    Afebrile seizures  

    Key points

    1. Symptoms at presentation can be non-specific, so early diagnostic consideration, investigation and empiric treatment is needed
    2. Prompt investigations (including lumbar puncture), together with early antibiotic administration, gives the best outcomes in bacterial meningitis
    3. Herpes Simplex Virus (HSV) encephalitis should be considered in any child with encephalopathy
    4. Aciclovir should be given to children with encephalitis of uncertain aetiology


    • Meningitis is inflammation of the meninges surrounding the brain and spinal cord
    • Encephalitis is inflammation of the brain parenchyma
    • Making a clinical distinction between meningitis and encephalitis is important as the common causative pathogens differ, however initial empiric management often covers both
    • Bacterial meningitis is a medical emergency which requires empiric antibiotic treatment without delay. A high index of suspicion for meningitis is needed in any unwell child, particularly if there is altered mental state or no clear focus
    • Presentation of bacterial meningitis can vary from fulminant (hours) to insidious (days) and can be altered by recent treatment with antibiotics
    • It is difficult to distinguish viral from bacterial meningitis clinically; children with meningitis should be treated with empiric antibiotics until the cause is confirmed
    • Unrecognised HSV encephalitis is a devastating illness with significant morbidity and mortality, however treatment with aciclovir can lead to a full recovery
    • Vaccines have significantly reduced the incidence of bacterial meningitis (Haemophilus influenzae type B (HiB) vaccine, Pneumococcal Conjugate Vaccine, Meningococcal ACWY)


    Red flag features in Red

    Meningitis Encephalitis


    • Fever
    • Immunisation history
    • Recent antibiotic exposure
    • Infant: 
      • minimal or non-specific symptoms
      • irritability
      • lethargy or drowsiness
      • poor feeding
      • hyper or hypotonia
      • vomiting and diarrhoea
      • temperature instability
    • Child, any of the above and/or:
      • headache
      • photophobia
      • nausea
      • altered conscious state  
    • Preceding URTI may be present
    • Seizures
    • Medical condition that may predispose child to meningitis (eg CNS anatomical abnormality or shunt, immunosuppression, immunodeficiency)


      • Fever
      • Features of altered mental state can be subtle and depend on the affected region of the brain:
        • unusual behaviour
        • confusion
        • personality change
        • emotional lability
      • Seizures (common)
      • Headache
      • Nausea and vomiting
      • Consider other causes of encephalopathy eg ADEM, toxins or metabolic
    • Full fontanelle
    • High-pitched cry 
    • Fever or hypothermia
    • Apnoea
    • Neck stiffness (may be absent in infants)
    • Focal neurological signs 
    • Purpuric rash is a late sign suggestive of meningococcal sepsis
    • Pain and involuntary effort to reduce meningeal “stretch” eg Kernig and Brudzinski signs (see Additional notes below)


    • Focal neurological signs


    • Lumbar puncture (LP)
      • Defer if there are focal neurological signs, markedly reduced GCS, cardiovascular compromise or coagulopathy
      • Urgent CSF microscopy and biochemistry (preferably with simultaneous blood glucose)
      • Based on clinical presentation and initial CSF results consider further investigations eg multiplex or specific PCR testing for enterovirus, parechovirus, Neisseria meningitidisStreptococcus pneumoniae or Herpes simplex virus (HSV)
    • FBE (may be normal), Glucose, Serum sodium, Blood cultures
    • Consider venous gas, coagulation studies if shock or coagulopathy suspected
    • Consider LFTs, metabolic and toxicology testing if non-infective cause of encephalopathy is suspected
    • Neuroimaging
      • Indications include:
          • encephalitis
          • focal neurological signs
          • signs of raised intracranial pressure (ICP)
          • diagnostic uncertainty (eg to look for a mass)
        • Is not routine in meningitis but is used to look for complications eg abscess, thrombosis
        • Normal head CT does not exclude raised ICP and should not influence the decision to perform an LP
        • MRI will provide more detailed information to guide diagnosis, but may require general anaesthetic
    • EEG may be helpful in suspected encephalitis


    Antibiotics must not be delayed for more than 30 minutes after the decision to treat is made
    Antimicrobial recommendations may vary according to local antimicrobial susceptibility patterns; please refer to local guidelines
    Suggested antibiotic regimen, if local guidelines not available:

    Age group

    Common organisms

    Empiric antibiotic



    0–2 months

    Group B streptococci (GBS), Escherichia coli, Listeria monocytogenes (rare)

    Benzylpenicillin 60 mg/kg IV 12H (week 1 of life) 6–8H (week 2–4 of life) 4H (>week 4 of life) and cefotaxime 50 mg/kg (max 2 g) IV 12H (week 1 of life), 6–8H (week 2–4 of life), 6H (>week 4 of life)

    Not advised

    ≥2 months

    N meningitidis, HiB,
    S pneumoniae

    Ceftriaxone 50 mg/kg (max 2 g) IV 12H or cefotaxime 50 mg/kg (max 2 g) IV 6H

    Add Vancomycin if Gram-positive cocci on Gram stain

    0.15 mg/kg (max 10 mg) IV 6H for 4 days





    Mycoplasma pneumoniae

    Other viruses: EBV, CMV, HHV6, Influenza

    Aciclovir 20 mg/kg IV 12H (<30 weeks gestation), 8H (>30 weeks gestation to <3 months corrected age)

    500 mg/m2  or 20 mg/kg IV 8H (3 months–12 years)
    10 mg/kg IV 8H (>12 years)

    Consider adding azithromycin

    Not advised


    • Current evidence for steroids in bacterial meningitis in children is mixed, but does suggest that steroids may reduce the risk of hearing loss
    • Steroids are not recommended in neonates due to possible effects on neurodevelopment
    • Give the first dose of IV dexamethasone just before or with the first dose of antibiotics. If giving the first dose of IV dexamethasone after initial antibiotic administration, this should ideally be done within 4 hours and not more than 12 hours after starting antibiotics.

    Ongoing management

    • All seizures in the setting of meningitis or encephalitis should be treated immediately
    • Consult the fluid management in meningitis/encephalitis guideline to assist with fluid balance (restriction is often required)
    • Monitor
        • Weight
        • Head circumference <2 yo
        • Vital signs including HR and BP
        • Electrolytes, urea, creatinine and blood glucose
      • Isolation: droplet precautions in first 24 hours of admission
      • Chemoprophylaxis for contacts

    Directed treatment*
    Antimicrobial recommendations may vary according to local antimicrobial susceptibility patterns; please refer to local guidelines
    Suggested antibiotic regimen, if local guidelines not available:



    Duration (days)

    N meningitidis



    S pneumoniae (penicillin sensitive)



    S pneumoniae (penicillin resistant)









    Organism not isolated


    7 minimum

    GBS, Listeria





    21 minimum

    * consider Infectious Diseases consultation for those with organisms resistant to first line therapy or with immediate hypersensitivity to penicillins/cephalosporins


    • All cases of presumed or confirmed N meningitidis and HiB should be notified to the Health Department immediately
    • Confirmed S pneumoniae is notifiable within 5 days
    • Follow state guidelines


    • Persistent fever after 4–6 days of treatment consider:
      • nosocomial infection
      • subdural effusion or empyema
      • cerebral abscess or parameningeal foci of ongoing infection
      • inadequate treatment
    • Hearing impairment
    • Neurodevelopmental impairment
    • Multi-organ involvement due to primary pathogen or secondary to septic shock (eg hepatic or cardiac)
    • Venous sinus thrombosis
    • Seizures, subsequent epilepsy
    • Permanent focal neurological deficit
    • Hydrocephalus


    • All children with encephalitis or bacterial meningitis should have a formal audiology assessment 6–8 weeks after discharge (earlier if concerns)
    • Neurodevelopmental progress should be monitored in outpatients
    • Consider investigating for complement deficiency if the child has had >1 episode of meningococcal disease

    Consider consultation with local paediatric team 

    • All children with suspected encephalitis or bacterial meningitis
    • All children with concern for non-infectious encephalopathy

    Consider transfer when

    • Haemodynamic or respiratory instability
    • Altered conscious state or focal neurological signs
    • Child requiring care above the level of comfort of the local hospital
    • Complications of meningitis or encephalitis or poor response to treatment

    For emergency advice and paediatric or neonatal ICU transfers, see Retrieval Services

    Consider discharge when 

    Children can complete IV treatment through HITH services if available once haemodynamically stable, afebrile and decision made regarding directed treatment

    Parent information sheet

    Lumbar Puncture
    Meningococcal infection

    Additional notes

    Kernig sign:

    1. Child is supine
    2. One hip and knee are flexed to 90 degrees by the examiner
    3. The examiner then attempts to passively extend child’s knee
    4. Positive if there is pain along spinal cord, and/or resistance to knee extension

    Brudzinski sign:

    1. Child is supine with legs extended
    2. The examiner grasps child’s occiput and attempts neck flexion
    3. Positive if there is reflex flexion of child’s hips and knees with neck flexion  

    Last Updated March, 2020

  • Reference List

    1. Beaman, M 2018 Community acquired acute meningitis and encephalitis: a narrative review, Medical Journal of Australia, viewed February 2020, <>
    2. Britton, P et al 2015, Consensus guidelines for the investigation and management of encephalitis, Medical Journal of Australia, viewed February 2020 < >
    3. Brouwer MC et al 2015, Corticosteroids for bacterial meningitis, Cochrane Library viewed February 2020 <>
    4. Muller M 2019, Pediatric bacterial meningitis, Emedicine Medscape, viewed February 2020 <>
    5. National Institute for Health and Care Excellence 2015, Meningitis (bacterial) and meningococcal septicaemia in under 16s: recognition, diagnosis and management, NICE, viewed February 2020 <>
    6. New South Wales Ministry of Health 2014, Infants and Children: Acute management of bacterial meningitis, NSW Health, viewed February 2020 <>
    7. Ogunlesi TA et al 2015, Use of corticosteroids for treatment of the newborn with bacterial meningitis, Cochrane library, viewed February 2020 <>
    8. Perth Children’s Hospital 2018, Meningitis guideline, viewed February 2020, <>
    9. Starship Child Health 2018, Meningitis guideline, viewed February 2020,  <>
    10. Therapeutic Guidelines 2019, Antibiotic, viewed February 2020<>
    11. Le Saux N 2018, Guidelines for the management of suspected and confirmed bacterial meningitis in Canadian children older than one month of age, Canadian Paediatric Society, viewed February 2020, <>
    12. Hardarson HS 2018, Acute viral encephalitis in children: Clinical manifestations and diagnosis; Pathogenesis, incidence and etiology, Treatment and prevention, UpToDate, viewed February 2020