Meningitis, acute bacterial

G00

*Notifiable condition. (N. meningitidis and H. influenzae )

This guideline applies to children > 60 days old. For the management of neonates, see Chapter: Prematurity and Neonatal Conditions, Meningitis bacterial, neonatal .

DESCRIPTION

Bacterial meningitis most commonly results from haematogenous dissemination of micro-organisms from a distant site, e.g. the nasopharynx.
In children, S. pneumoniae and N. meningitides are the usual pathogens.

Note:

Tuberculosis, cryptococcal and partially treated acute bacterial meningitis should be considered when the clinical and laboratory features are not typical of pyogenic meningitis, or when there is a slow onset of disease (> 2 days), especially in any high risk settings such as immune suppression, TB contact and malnourished children.

Differentiation of TB or cryptococcal meningitis from acute bacterial meningitis is not always easy on presentation.

Complications include:

  • Raised intracranial pressure due to cerebral oedema, subdural effusion/empyema or hydrocephalus.
  • Other acute complications include:
    • cerebral infarctions,
    • shock,
    • seizures,
    • metastatic infection, e.g. arthritis, pneumonia, pericarditis,
    • disseminated intravascular thrombosis,
    • inappropriate antidiuretic hormone (ADH) secretion.

Long-term neurological sequelae include deafness, blindness, mental retardation and motor paralysis, e.g. hemiparesis.

DIAGNOSTIC CRITERIA

Clinical

  • Fever.
  • Feeding problems.
  • Headache.
  • Irritability.
  • Vomiting.
  • Lethargy.
  • Convulsions
  • Photophobia.
  • Signs of meningeal irritation. In young infants signs of meningism are often absent.
  • Signs of increased intracranial pressure, e.g. bulging anterior fontanel.
  • Papilloedema is not a useful sign in young children with meningitis. It is difficult to elicit and may be absent even with acutely raised ICP.

Investigations

  • Lumbar puncture (LP) – send CSF for biochemistry, microscopy and culture.
    • In typical cases of bacterial meningitis: CSF glucose is low, CSF protein is raised, CSF pleocytosis with neutrophil predominance is found, and bacteria may be visualised on Gram stain. However, many cases do not have these typical CSF findings. All abnormal findings should lead to serious considerations of acute bacterial meningitis.
      If contra-indications to LP are present, defer LP and initiate treatment immediately. For contra-indications to LP see Chapter: The Nervous System, section Lumbar Puncture .
  • Clinical meningococcaemia (septicaemia) with petechiae/purpura.
    • Confirm with skin scrape, Gram stain and blood culture.

GENERAL AND SUPPORTIVE MEASURES

  • Admit to high or intensive care unit, if appropriate.
  • Monitor, where indicated:
    • neurological status,
    • respiration,
    • heart rate,
    • body temperature,
    • blood pressure,
    • haematocrit,
    • acid-base status,
    • electrolytes,
    • blood glucose,
    • blood gases,
    • fluid balance, i.e. hydration,
    • serum and urine osmolality.
  • Ensure adequate nutrition by enteral feeding where possible.
    • Use a nasogastric tube if necessary.
    • If enteral feeding is not possible, give intravenous fluids: paediatric or neonatal maintenance solution with dextrose.

MEDICINE TREATMENT

Antibiotic therapy

Empiric treatment:

  • Ceftriaxone, IV, 50 mg/kg/dose 12 hourly.

Adjust antimicrobial therapy according to culture and sensitivity.

Treatment duration in culture positive meningitis:

  • N meningitides : 5 days
  • S pneumoniae : 10 days
  • H influenza: 10 days
  • Other gram negative bacilli: 21 days

In stable patients with uncomplicated culture-negative meningitis, 5 days is adequate.

In complicated or non-responsive cases, a longer duration of therapy may be required.
Re-assess antimicrobial therapy when blood and CSF culture and sensitivity results become available, or when improvement is not evident within 72–96 hours.

Seek immediate advice on what treatment to start with when ventriculo-peritoneal shunt infection, spread from sinuses, mastoids, or direct penetrating source of infection is present.

For shunts:

  • 3ʳᵈ generation cephalosporin, e.g.:
  • Ceftriaxone, IV, 50 mg/kg/dose 12 hourly.
    PLUS
  • Vancomycin, IV, 15 mg/kg/dose, 6 hourly infused over 1 hour.
    PLUS
  • Rifampicin, IV, 10 mg/kg 12 hourly, do not exceed 600 mg/dose (in patients where TB has been excluded).

Fever and headache:

  • Paracetamol, oral, 15 mg/kg/dose, 6 hourly as required.

Convulsions

See Status epilepticus (convulsive) .

Raised intracranial pressure or cerebral oedema

Elevate head of bed ± 30°.
Maintain PaCO₂ at 4–5 kPa (30–35 mmHg); intubate and ventilate if necessary.
Avoid fluid overload.

  • Mannitol, IV, 250 mg/kg administered over 30–60 minutes.
  • Dexamethasone, IV, 0.5 mg/kg 12 hourly.

Chemoprophylaxis for close contacts

A close contact is defined as someone living in the same household, dormitory, institution, children in the same crèche, or any other “kissing” contact. Health care workers who have intimate contact should receive prophylaxis.

N. meningitidis

  • Ciprofloxacin, oral, as a single dose.
    • If < 12 years of age: 10 mg/kg.
    • If > 12 years of age: 500 mg.

Note:
If < 12 years of age and able to swallow, use a single 250 mg tablet.

OR

  • Ceftriaxone, IM, single dose
    • If < 12 years of age: 125 mg.
    • If > 12 years of age: 250 mg.

Close contacts who are pregnant:

  • Ceftriaxone, IM, 250 mg.

H. influenzae prophylaxis for all contacts under 5 years who are household contacts (including index case) or day care contacts:

  • Rifampicin, oral, 20 mg/kg/dose, once daily for 4 days.
    • Maximum dose: 600 mg
    • Neonatal dose: 10 mg/kg/dose, once daily for 4 days.

Check vaccination status of index case and all contacts; and update if necessary - Refer to Primary Health Care Standard Treatment Guidelines and Essential Medicines List, Immunisation .

REFERRAL

  • Where lumbar puncture is deferred due to suspected raised intracranial pressure and/or localising signs start bacterial and tuberculous meningitis treatment immediately.
  • Meningitis with complications.
  • All cases of suspected shunt infection. Start treatment immediately before referral.