Bacterial Meningitis - Adult

Quick Answer

Bacterial meningitis is a life-threatening infection of the meninges requiring immediate empirical antibiotics (Ceftriaxone 2g IV q12h + Vancomycin 15-20 mg/kg IV q8-12h) after blood cultures are drawn. Dexamethasone 10 mg IV should be given before or with the first dose of antibiotics for suspected pneumococcal meningitis, then every 6 hours for 4 days. Lumbar puncture should be performed urgently unless contraindicated (focal neuro deficit, papilloedema, GCS below 10, immunocompromised, new-onset seizure, history of CNS disease). Mortality ranges from 5-15% with early treatment, but increases significantly with delays. The classic triad (fever, headache, nuchal rigidity) is present in only 44% of patients; altered mental status completes the classic presentation in 95% of cases.

---

ACEM Exam Focus

Fellowship Written (SAQs):

• CT brain criteria before lumbar puncture (Hasbun criteria)
• Empirical antibiotic selection for different age groups and risk factors
• CSF interpretation: bacterial vs viral vs tubercular vs fungal
• Dexamethasone indications, timing, and evidence
• Meningococcal prophylaxis regimens for contacts
• Complications: cerebral edema, seizures, SIADH, cranial nerve palsies
• Antibiotic resistance patterns (penicillin-resistant pneumococcus)

Fellowship OSCE:

• Resuscitation station: Leading management of septic meningitis patient
• Communication: Breaking bad news to family about meningitis prognosis
• Procedural: Lumbar puncture technique and contraindication assessment
• Clinical reasoning: Differentiating bacterial from viral meningitis

Primary Exam:

• Anatomy of meninges, blood-brain barrier
• Physiology of CSF production and circulation
• Pathophysiology of bacterial translocation into CNS
• Pharmacology of third-generation cephalosporins and vancomycin
• Steroid mechanism in reducing inflammation

---

Key Points

---

Epidemiology

Australian/NZ Specific

• Incidence: Approximately 0.7-1.0 per 100,000 population per year (Aus) PMID: 29195450
• Meningococcal disease: 0.5-1.0 per 100,000; seasonal peaks winter-spring PMID: 29195450
• Indigenous Australians: 2-3 times higher incidence of invasive meningococcal disease compared to non-Indigenous PMID: 29195450
• Serogroup distribution: B most common (60%), followed by W (20%), Y (15%) PMID: 29195450
• Vaccination impact: MenACWY vaccine introduced to NIP in 2018, MenB vaccine available but not on NIP

---

Pathophysiology

Mechanism

Bacterial meningitis develops through a multi-step process:

1. Colonisation: Bacteria colonise nasopharynx (asymptomatic carriage in 5-10% for N. meningitidis, 40-60% for S. pneumoniae)
2. Mucosal invasion: Bacteria breach mucosal epithelium via IgA proteases, pilus-mediated adhesion
3. Bacteraemia: Bacteria enter bloodstream, survive via capsular polysaccharides evading phagocytosis
4. Cross blood-brain barrier: Transcytosis across choroid plexus, disruption of tight junctions, or via infected monocytes ("Trojan horse")
5. CSF infection: Bacteria proliferate in subarachnoid space (deficient complement, antibodies, low phagocyte activity)
6. Inflammatory cascade: Bacterial lysis releases cell wall components (LPS in gram-negative, teichoic acid in gram-positive) → trigger cytokine storm (TNF-α, IL-1β, IL-6) → blood-brain barrier disruption, cerebral edema, neuronal injury

Pathological Progression

Nasopharyngeal colonisation → Mucosal invasion → Bacteraemia → BBB penetration → CSF proliferation → Inflammatory cascade → Cerebral edema → Increased ICP → Cerebral herniation (if untreated)

Why It Matters Clinically

• Antibiotic-induced lysis paradox: Antibiotics rapidly kill bacteria, causing massive release of inflammatory mediators → this is why dexamethasone is given BEFORE antibiotics
• Cerebral edema mechanisms: (1) Vasogenic edema from BBB disruption, (2) Cytotoxic edema from neuronal injury, (3) Interstitial edema from impaired CSF flow
• Cerebral blood flow: Initially increased (luxury perfusion), then decreases due to vasculitis, microthrombi → cerebral ischemia
• Seizure risk: Cerebral irritation from inflammation, cortical irritation from cytotoxic edema

---

Clinical Approach

Recognition

High-risk presentations requiring immediate consideration of bacterial meningitis:

• Fever plus headache plus neck stiffness (classic triad - present in only 44%)
• Fever plus altered mental status (present in 70-80%)
• Fever plus new-onset seizure (present in 15-25%)
• Fever plus petechial/purpuric rash (meningococcal - present in 50-75%)
• Immunosuppressed patient with fever and headache
• Elderly patient with altered mental status (atypical presentation)

Initial Assessment

Primary Survey (ABCDE)

• A: Assess airway protection; GCS below 8 requires intubation for airway protection and hyperventilation to reduce ICP (target PaCO2 35-40 mmHg)
• B: Respiratory rate, oxygen saturation; maintain SpO2 94-98% (avoid hyperoxia which can worsen cerebral vasoconstriction)
• C: Assess for septic shock: hypotension (SBP below 90 mmHg), tachycardia, prolonged capillary refill above 2 seconds; check for signs of DIC (purpura, oozing from venepuncture sites)
• D: Assess GCS, pupils (size, reactivity, anisocoria), focal neuro deficits (hemiparesis, facial droop, aphasia), papilloedema
• E: Full skin examination for petechial rash (non-blanching on glass test); check ENT for otitis media, sinusitis (pneumococcal source)

History

Key Questions

Red Flag Symptoms

Examination

General Inspection

• Appearance: Toxic appearance, lethargic, irritable (younger patients), confused
• Vital signs: Fever (temperature above 38.0°C), tachycardia, hypotension (septic shock)
• Skin: Petechiae/purpura (meningococcal), check non-blanching with glass slide

Specific Findings

---

Investigations

Immediate (Resus Bay)

Standard ED Workup

Advanced/Specialist

CSF Analysis Interpretation

CSF Lactate: A level above 4.0 mmol/L has 93% sensitivity and 96% specificity for bacterial meningitis PMID: 16963907

---

Management

Immediate Management (First 10 minutes)

1. Establish IV access (2 large-bore cannulas)
2. Obtain blood cultures (2 sets from different sites) - DO NOT delay antibiotics for cultures
3. Administer Dexamethasone 10 mg IV BEFORE or WITH first antibiotics (if pneumococcal suspected)
4. Administer empirical antibiotics (see below)
5. Assess for septic shock: give 500-1000 mL normal saline bolus if hypotensive
6. Assess for CT criteria (Hasbun criteria)
   - If YES: Blood cultures + antibiotics + steroids → CT brain → LP (if CT normal)
   - If NO: Blood cultures → LP → antibiotics + steroids (administer within 30 min of LP)

Resuscitation

Airway

• Intubation if GCS below 8, inability to protect airway, or respiratory failure
• RSI with cervical spine protection (if trauma suspected)
• Maintain PaCO2 35-40 mmHg (avoid hyperventilation below 35 mmHg which reduces cerebral blood flow)

Breathing

• Maintain SpO2 94-98% (avoid hyperoxia above 98% which causes cerebral vasoconstriction)
• Mechanical ventilation: tidal volume 6-8 mL/kg ideal body weight, PEEP 5-10 cm H₂O
• Consider recruitment manoeuvres if hypoxaemia persists

Circulation

• Septic shock protocol: 30 mL/kg crystalloid bolus, reassess
• Vasopressors if SBP remains below 90 mmHg after fluid bolus:
  • Noradrenaline 0.05-0.5 μg/kg/min (first-line)
  • Vasopressin 0.03 U/min (second-line)
• Monitor for DIC: platelets, fibrinogen, PT/INR
• Replace platelets if below 50,000, cryoprecipitate if fibrinogen below 1.5 g/L

Medications

Empirical Antibiotics

Vancomycin target trough: 15-20 μg/mL (for meningitis, higher than standard 10-15 μg/mL for pneumonia)

Dexamethasone

Evidence: de Gans and van de Beek NEJM 2002 - dexamethasone reduced unfavourable outcomes (15% vs 25%) and mortality (7% vs 15%) in pneumococcal meningitis PMID: 12432042

Adjunctive Therapies

Target-Specific Therapy (After Pathogen Identified)

Paediatric Dosing

Ongoing Management

• Neurological monitoring: Hourly GCS, pupil checks, assess for new focal deficits
• Haemodynamic monitoring: BP, HR, urine output (goal 0.5-1 mL/kg/hr), lactate trend
• ICP monitoring: Consider if GCS below 8 and CT shows cerebral edema; external ventricular drain if obstructive hydrocephalus
• Repeat LP: Consider in 48-72 hours if clinical deterioration or no improvement
• Complication surveillance: Daily cranial nerve assessment (III, IV, VI, VII, VIII), monitor for subdural empyema, brain abscess (repeat CT if focal signs develop)

Definitive Care

• ICU admission: Required for GCS below 12, septic shock, need for mechanical ventilation, or complications requiring neurosurgical consultation
• Infectious diseases consultation: For antibiotic de-escalation based on culture/sensitivity results
• Neurosurgery consultation: For obstructive hydrocephalus (EVD placement), subdural empyema, brain abscess, or skull base osteomyelitis
• Rehabilitation: Physical therapy, occupational therapy, speech therapy for survivors with neurological sequelae
• Audiology assessment: Mandatory for pneumococcal meningitis survivors (30-50% develop hearing loss)

---

Disposition

Admission Criteria

• ALL patients with suspected or confirmed bacterial meningitis require hospital admission
• ICU/HDU admission for:
  • GCS below 12
  • Septic shock requiring vasopressors
  • Need for mechanical ventilation
  • Signs of raised ICP
  • Complications (subdural empyema, brain abscess)

ICU/HDU Criteria

• GCS below 12 or declining GCS
• Septic shock requiring vasopressors
• Respiratory failure requiring mechanical ventilation
• Raised ICP requiring neurosurgical intervention or EVD
• Coagulopathy/DIC requiring blood product support
• Age above 65 or immunocompromised (high-risk for deterioration)

Discharge Criteria

Never discharge from ED for suspected bacterial meningitis

Follow-up

• Outpatient infectious diseases: For completion of IV antibiotics if discharged from hospital
• Audiology: Repeat hearing assessment 3-6 months post-discharge
• Neurology: Follow-up for cognitive assessment, seizure management
• Vaccination: Ensure pneumococcal, meningococcal (MenACWY, MenB) vaccinations updated post-recovery
• GP letter: Document pathogen identified, antibiotic course, complications, follow-up plan

---

Special Populations

Paediatric Considerations

• Age under 3 months: Add Gentamicin 5 mg/kg/day for empirical coverage of gram-negative bacilli (E. coli, Klebsiella)
• Viral meningitis: More common in children under 2 years; consider HSV PCR if seizures or encephalopathic
• Antibiotic dosing: Weight-based, higher mg/kg doses than adults due to higher CSF penetration requirements
• Dexamethasone: Controversial in infants; consider only if Haemophilus influenzae suspected

Pregnancy

• Ceftriaxone: Safe in all trimesters (Pregnancy Category B)
• Vancomycin: Safe (Pregnancy Category C, benefits outweigh risks)
• Ampicillin: Safe (Pregnancy Category B)
• Dexamethasone: Generally avoided unless benefits clearly outweigh risks; discuss with obstetrics
• Antibiotic penetration: Altered due to increased plasma volume, higher doses may be needed
• Fetal monitoring: Continuous fetal heart rate monitoring if admitted to ICU

Elderly

• Atypical presentation: May present only with altered mental status without classic triad
• Listeria monocytogenes: Always add Ampicillin 2g IV q4h to empirical regimen
• Comorbidities: Higher mortality (25-40%) due to pre-existing cardiac, pulmonary, renal disease
• Antibiotic dosing: Consider renal function adjustment for vancomycin, aminoglycosides
• Cognitive outcomes: Higher risk of permanent neurological deficits

Indigenous Health

Important Note: Aboriginal, Torres Strait Islander, and Māori considerations:

• Higher incidence: Indigenous Australians have 2-3 times higher incidence of invasive meningococcal disease PMID: 29195450
• Delayed presentation: Rural/remote access barriers lead to later presentation and worse outcomes
• Māori (NZ): Higher rates of pneumococcal meningitis; cultural safety requires whānau (family) involvement
• Cultural safety:
  • Involve Aboriginal Health Workers or Māori cultural liaisons
  • Respect traditional healing practices alongside western medicine
  • Consider extended family decision-making structures
  • "Language barriers: Use certified interpreters, not family members"
• Social determinants: Overcrowded housing facilitates transmission; address housing recommendations with public health
• Vaccination: Ensure MenACWY and pneumococcal vaccinations are up to date; lower vaccine uptake in some communities
• Follow-up: Arrange culturally appropriate rehabilitation services in community where possible

---

Pitfalls & Pearls

---

Viva Practice

---

OSCE Scenarios

Station 1: Resuscitation - Bacterial Meningitis with Septic Shock

Format: Resuscitation Time: 11 minutes Setting: ED Resuscitation Bay

Candidate Instructions:

You are the team leader in ED. A 45-year-old male has just arrived by ambulance with suspected bacterial meningitis. He is febrile, tachypnoeic, and hypotensive. The nurse has cannulated one 18G peripheral line. You have a registrar, a nurse, and an intern available. Please lead the assessment and management of this patient.

Examiner Instructions: The patient is critically unwell with bacterial meningitis and early septic shock. Initial vitals: GCS 12 (E3 V4 M5), temperature 39.5°C, BP 85/50 mmHg, HR 125 bpm, RR 28/min, SpO2 95% on room air. He has marked nuchal rigidity and photophobia. No rash visible on brief inspection. Fundoscopy not performed.

Expected progression:

• Candidate should recognise urgency and immediate life threats
• Prioritise ABCDE approach with septic shock management
• Give time-critical antibiotics immediately
• Consider airway protection (GCS 12 but stable for now)
• Initiate sepsis bundle: lactate, blood cultures, fluids, vasopressors
• Assess for CT criteria before LP
• Communicate clearly with team using closed-loop communication

Marking Criteria:

Expected Standard:

• Pass: 9/15
• Key discriminators:
  • "FAIL: Delays antibiotics for CT or LP"
  • "PASS: Gives antibiotics immediately after blood cultures"
  • "FAIL: Does not assess for septic shock or give fluid bolus"
  • "PASS: Recognises septic shock, initiates fluid resuscitation"

---

Station 2: Clinical Reasoning - CSF Interpretation

Format: Clinical Reasoning Time: 11 minutes Setting: ED Consulting Room

Candidate Instructions:

A 28-year-old female presents with fever, headache, neck stiffness, and photophobia for 18 hours. You performed lumbar puncture (no CT needed as Hasbun criteria negative). The CSF results are as follows:

Opening pressure: 28 cm H₂O Appearance: Clear, colourless WBC: 280/μL (lymphocytes 85%, neutrophils 15%) Protein: 65 mg/dL Glucose: 55 mg/dL (serum glucose 100 mg/dL) Gram stain: No organisms seen Bacterial PCR panel: Positive for Enterovirus

Please interpret these findings and provide your management plan.

Examiner Instructions: The CSF findings are consistent with viral meningitis (Enterovirus). The candidate should:

• Interpret CSF correctly (viral vs bacterial vs tubercular)
• Recognise Enterovirus as cause (most common viral meningitis)
• Stop antibiotics (if already started) or avoid starting them
• Provide supportive care plan
• Discuss safe discharge criteria
• Recognise red flags requiring reassessment

Marking Criteria:

Expected Standard:

• Pass: 8/13
• Key discriminators:
  • "FAIL: Starts antibiotics for viral meningitis"
  • "PASS: Recognises viral pattern, avoids unnecessary antibiotics"
  • "FAIL: Sends patient home without safe discharge criteria"
  • "PASS: Provides comprehensive discharge plan with red flag education"

---

Station 3: Communication - Breaking Bad News about Meningitis

Format: Communication Time: 11 minutes Setting: Relatives' Room

Candidate Instructions:

You are the FACEM managing a 22-year-old male admitted yesterday with bacterial meningitis (Neisseria meningitidis, confirmed by CSF culture). Despite appropriate antibiotics, he has deteriorated overnight: GCS dropped to 7, pupils are dilated and fixed bilaterally, CT shows extensive cerebral edema with early herniation. His parents are in the relatives' room. Please go and speak with them. The nurse is available to support you.

Examiner Instructions: The parents are very distressed and anxious. Expected behaviours:

• Uses SPIKES protocol (Setting, Perception, Invitation, Knowledge, Empathy, Strategy)
• Delivers bad news clearly but compassionately
• Assesses parents' understanding and emotional state
• Allows silence and questions
• Discusses prognosis honestly but sensitively
• Explains plan for ongoing care (ICU, neurosurgery involvement)
• Offers support: social work, chaplaincy, time alone with son
• Avoids medical jargon, uses plain language
• Maintains eye contact, empathetic body language

Actor/Patient Brief (Parents): You are very worried about your son. He was healthy yesterday. You haven't seen him since ICU admission. You want to know:

• What is happening to him?
• Will he recover?
• Can we see him?
• What are you doing for him?

Marking Criteria:

Expected Standard:

• Pass: 7/12
• Key discriminators:
  • "FAIL: Delays visiting parents, spends too long on medical details first"
  • "PASS: Goes to relatives' room immediately after stabilising patient"
  • "FAIL: Uses medical jargon, insensitive body language"
  • "PASS: Uses SPIKES protocol, empathetic communication, offers support"
  • FAIL: False hope ("he'll be fine") or overly blunt ("he's going to die")
  • "PASS: Honest but compassionate communication about poor prognosis"

---

SAQ Practice

Question 1 (6 marks)

Stem: A 55-year-old male presents to ED with fever, headache, and confusion for 24 hours. He has a history of alcohol dependence. On examination, GCS 13/15 (E3 V4 M6), temperature 38.5°C, BP 130/80 mmHg, HR 110 bpm, RR 18/min. He has marked nuchal rigidity. No focal neuro deficits. No rash visible. Fundoscopy normal.

Question: List the empirical antibiotic regimen you would prescribe for this patient, including doses and frequency.

Model Answer:

1. Ceftriaxone 2g IV every 12 hours (2 marks)
2. Vancomycin 15-20 mg/kg IV every 8-12 hours (2 marks)
3. Ampicillin 2g IV every 4 hours (2 marks)

Examiner Notes:

• Accept: Cefotaxime 2g IV every 4-6 hours as alternative to Ceftriaxone
• Accept: Meropenem 2g IV every 8 hours if penicillin allergy (with vancomycin)
• Do not accept: Ceftriaxone alone (vancomycin required for penicillin-resistant pneumococcus)
• Do not accept: Ampicillin alone (does not cover meningococcus, pneumococcus)
• Credit given for explaining rationale:
  • "Ceftriaxone/Vancomycin: Cover pneumococcus, meningococcus, H. influenzae"
  • "Ampicillin: Added for Listeria monocytogenes (patient above 50, alcohol-dependent, high risk)"
• PMID: 11943538

---

Question 2 (8 marks)

Stem: A 32-year-old female presents with fever, headache, neck stiffness, and petechial rash on her trunk and extremities. You suspect meningococcal meningitis. The patient lives with her partner and 2 children (aged 4 and 7 years).

Question: List the chemoprophylaxis regimen(s) you would recommend for this patient's close contacts.

Model Answer:

Contacts requiring prophylaxis:

• Partner (household contact) (1 mark)
• 2 children (household contacts) (1 mark)

Acceptable prophylaxis regimens (adults):

1. Rifampin 600 mg orally every 12 hours for 2 days (4 doses) (2 marks)
2. OR Ciprofloxacin 500 mg orally single dose (2 marks)
3. OR Ceftriaxone 250 mg intramuscularly single dose (2 marks)

Paediatric prophylaxis:

• Rifampin: 10 mg/kg (max 600 mg) every 12 hours for 2 days (children above 1 month)
• Ceftriaxone: 125 mg IM single dose (below 12 years), 250 mg IM single dose (12 years and above)
• Ciprofloxacin: 20 mg/kg (max 500 mg) single dose (adult dose; ciprofloxacin NOT routinely used in children)

Examiner Notes:

• Accept: All three regimens (rifampin, ciprofloxacin, ceftriaxone) are equally acceptable
• Note: Ciprofloxacin preferred for compliance (single dose), but check local resistance patterns
• Note: Rifampin causes orange discoloration of secretions and interacts with many drugs (OCP, warfarin)
• Note: Ceftriaxone is drug of choice for pregnant contacts (rifampin and ciprofloxacin contraindicated in pregnancy)
• Note: Prophylaxis should be given within 24 hours of index case identification (less effective after 14 days)
• Note: Index patient also requires prophylaxis if treated with penicillin (penicillin does not eradicate nasopharyngeal carriage)
• PMID: 31201542

---

Question 3 (10 marks)

Stem: A 40-year-old male presents with suspected bacterial meningitis. You have obtained blood cultures and are preparing to perform lumbar puncture.

Question: List the criteria (Hasbun criteria) that indicate a CT brain should be performed before lumbar puncture.

Model Answer:

Hasbun criteria (any ONE indicates CT before LP):

1. Immunocompromised state (1 mark)

   • HIV/AIDS
   • Immunosuppressive therapy (chemotherapy, high-dose steroids)
   • Post-transplantation
   • Diabetes mellitus

2. History of central nervous system disease (1 mark)

   • Prior stroke
   • Intracranial tumour
   • Brain abscess
   • Cerebral aneurysm

3. New-onset seizure (1 mark)

   • Seizure within 1 week of presentation

4. Papilloedema on fundoscopy (1 mark)

   • Blurring of optic disc margins
   • Venous engorgement

5. Abnormal level of consciousness (1 mark)

   • GCS below 10 (obtundation, coma)

6. Focal neurological deficit (1 mark)

   • Hemiparesis
   • Facial droop
   • Visual field defect
   • Aphasia
   • Dilated, non-reactive pupil

Additional marks for completeness:

• Recognises that antibiotics should be given IMMEDIATELY after blood cultures, before sending to CT (2 marks)
• Explains rationale: CT excludes mass lesion or cerebral edema that would increase risk of cerebral herniation with LP (2 marks)

Examiner Notes:

• Accept: Any of the 6 Hasbun criteria listed
• Credit given for examples under each criterion (e.g., HIV, chemotherapy for immunocompromised; stroke, tumour for CNS disease)
• Credit given for explanation of antibiotic timing (give before CT)
• Credit given for rationale (identify contraindication to LP)
• Do not accept: Headache alone (not a Hasbun criterion)
• Do not accept: Fever alone (not a Hasbun criterion)
• Do not accept: Neck stiffness alone (not a Hasbun criterion)
• Critical error: Delaying antibiotics for CT - this is a serious mistake (deduct marks)
• PMID: 11211029

---

Question 4 (8 marks)

Stem: A 25-year-old male presents with fever, headache, and neck stiffness. You perform lumbar puncture. The CSF results are as follows:

• Opening pressure: 30 cm H₂O
• Appearance: Turbid, cloudy
• WBC: 2,500/μL (neutrophils 92%, lymphocytes 8%)
• Protein: 150 mg/dL
• Glucose: 30 mg/dL (serum glucose 100 mg/dL)
• Gram stain: Gram-positive diplococci seen
• Bacterial PCR: Positive for Streptococcus pneumoniae

Question:

a) Interpret these CSF findings. (4 marks)

b) Outline your management plan for this patient, including antibiotics and adjunctive therapies. (4 marks)

Model Answer:

a) CSF interpretation (4 marks):

• Consistent with bacterial meningitis (1 mark)
• Specific findings:
  • Elevated opening pressure (30 cm H₂O) (0.5 marks)
  • Turbid/cloudy appearance (0.5 marks)
  • Marked pleocytosis with neutrophil predominance (WBC 2,500/μL, 92% neutrophils) (1 mark)
  • Markedly elevated protein (150 mg/dL) (0.5 marks)
  • Low glucose (30 mg/dL = 30% of serum) (0.5 marks)
  • Gram stain shows gram-positive diplococci (pathognomonic for Streptococcus pneumoniae) (0.5 marks)

b) Management plan (4 marks):

Immediate:

• Antibiotics (already started empirically): Continue Ceftriaxone 2g IV q12h + Vancomycin 15-20 mg/kg IV q8h (1 mark)
• Dexamethasone 10 mg IV q6h for 4 days (1 mark) - given before or with first antibiotics

Adjunctive therapies:

• Analgesia: Paracetamol 1g IV/PO q4-6h for fever and headache (0.5 marks)
• Fluid management: Maintain euvolaemia, monitor for SIADH (common in bacterial meningitis) (0.5 marks)
• Seizure prophylaxis: Not routine; treat seizures if they occur (Levetiracetam or Phenytoin) (0.5 marks)

Ongoing:

• ICU admission: Consider for close monitoring (GCS assessment, ICP monitoring if needed) (0.5 marks)
• Neurosurgical consult: If neurological deterioration or signs of raised ICP (hydrocephalus, subdural empyema) (0.5 marks)

Follow-up:

• Audiology assessment: 30-50% of pneumococcal meningitis survivors develop hearing loss; mandatory audiology follow-up (0.5 marks)

Examiner Notes:

• Credit given for recognising pneumococcal meningitis (gram-positive diplococci)
• Credit given for appropriate antibiotic regimen (Ceftriaxone + Vancomycin)
• Credit given for dexamethasone (critical: must be given before or with first antibiotics)
• Credit given for adjunctive therapies (analgesia, fluid monitoring, seizure management)
• Credit given for audiology follow-up (important complication)
• Do not accept: Ampicillin (not needed - patient below 50, not immunocompromised)
• Do not accept: Withholding dexamethasone (dexamethasone reduces morbidity and mortality in pneumococcal meningitis)
• Critical error: Not giving dexamethasone, or giving it after antibiotics (both reduce efficacy)
• PMID: 12432042 (dexamethasone evidence)
• PMID: 11943538 (antibiotic management)

---

Australian Guidelines

Therapeutic Guidelines Australia (eTG)

Antibiotic Guidelines - Bacterial Meningitis (Adults):

• Empirical therapy (adults below 50, immunocompetent):

  • Ceftriaxone 2g IV q12h OR Cefotaxime 2g IV q6h
  • PLUS Vancomycin 15-20 mg/kg IV q8-12h

• Empirical therapy (adults above 50 OR immunocompromised):

  • Ceftriaxone 2g IV q12h OR Cefotaxime 2g IV q6h
  • PLUS Vancomycin 15-20 mg/kg IV q8-12h
  • PLUS Ampicillin 2g IV q4h

• Dexamethasone:

  • Indicated for suspected or confirmed pneumococcal meningitis
  • 10 mg IV before or with first antibiotics, then q6h for 4 days
  • Discontinue if organism is not pneumococcus (except H. influenzae)

• Duration of therapy:

  • "Pneumococcal: 10-14 days"
  • "Meningococcal: 5-7 days"
  • "Listeria: 14-21 days"
  • "H. influenzae: 7-10 days"

Australian Technical Advisory Group on Immunisation (ATAGI)

Meningococcal vaccination recommendations:

• MenACWY (quadrivalent conjugate vaccine):

  • Added to National Immunisation Program (NIP) in 2018
  • Dose at 12 months, booster at 12 years
  • Catch-up program for adolescents and young adults (15-19 years)

• MenB (Bexsero):

  • Available on private prescription
  • Not on NIP (due to cost considerations)
  • "Recommended for high-risk groups: asplenia, complement deficiency, HIV, laboratory workers"

State-Specific Protocols

New South Wales:

• Notifiable condition: Notify NSW Public Health Unit within 24 hours
• Contact tracing: NSW PHU coordinates prophylaxis for close contacts
• Outbreak management: School or community outbreak triggers mass vaccination program

Victoria:

• Victorian Department of Health: Notifiable disease guidelines
• Enhanced surveillance for meningococcal disease
• Contact prophylaxis: Coordinated by Public Health Units

Queensland:

• Communicable Diseases Network Australia (CDNA) guidelines
• Queensland Health: Meningococcal disease fact sheets
• Remote and Indigenous communities: Targeted vaccination programs

---

Remote/Rural Considerations

Pre-Hospital

Royal Flying Doctor Service (RFDS):

• Antibiotics: Ceftriaxone 2g IM can be given by RFDS flight nurses prior to ED arrival
• Dexamethasone: 10 mg IV/IM should be given with or before antibiotics
• Airway management: Intubation for GCS below 8, deteriorating neurological status
• Transport: Pressurised aircraft (King Air, Pilatus PC-12) maintains sea level pressure to minimise ICP changes

Ambulance Service Guidelines:

• PEN chart (Pain, Elevate, Nothing by mouth) for patient comfort
• Oxygen: Maintain SpO2 94-98%, avoid hyperventilation (PaCO2 35-40 mmHg)
• Fluids: 500-1000 mL normal saline bolus for hypotension, avoid overhydration
• Monitoring: Hourly GCS, pupil checks, neurological assessment
• PPE: Droplet precautions for suspected meningococcal disease (mask, gloves, gown)

Resource-Limited Setting

CARPA Standard Treatment Manual (remote clinics):

• Immediate management:

  • Give Ceftriaxone 2g IM (if IV access not available)
  • Give Dexamethasone 10 mg IM (if IV not available)
  • Do NOT delay retrieval for LP
  • Blood cultures if possible, but do NOT delay antibiotics

• Lumbar puncture:

  • Generally contraindicated in remote clinics (no CT backup, risk of cerebral herniation)
  • Only consider if patient stable, no focal neuro deficits, no papilloedema
  • Transport to referral centre for definitive diagnosis

• Retrieval:

  • Category 1 (emergency) retrieval for suspected bacterial meningitis
  • Call RFDS/RSQ/MedSTAR immediately after first antibiotic dose
  • Use ISBAR format for handover

Retrieval

Retrieval criteria:

• Urgent (Category 1):

  • GCS below 12 or declining
  • Septic shock requiring vasopressors
  • New-onset seizures
  • Raised ICP signs (papilloedema, Cushing's triad)
  • Petechial rash (meningococcal) with systemic symptoms

• Standard (Category 2):

  • GCS 12-14 but stable
  • No septic shock
  • No focal neuro deficits
  • No signs of raised ICP

RFDS Retrieval Team:

• Composition: Flight nurse + medical officer (GP, anaesthetist, or ED specialist)
• Capabilities:
  • Intubation and mechanical ventilation
  • Vasopressor administration (noradrenaline, vasopressin)
  • Intracranial pressure monitoring (if available)
  • Advanced life support
• Aircraft:
  • Beechcraft King Air B200/B300
  • Pilatus PC-12 NG
  • Pressurised to sea level
  • ICU-capable environment

Telemedicine

Remote consultation:

• Video consultation: Use secure telemedicine platform (e.g., QH Video Consult, MedStar Connect)
• Information required: ISBAR handover, vital signs, examination findings, antibiotic timing
• Specialist input: Infectious diseases, neurology, intensive care, neurosurgery
• Antibiotic guidance: Confirm empirical regimen, discuss de-escalation once cultures available
• Disposition: Discuss retrieval priority, destination hospital, ICU bed availability

---

References

Guidelines

1. Australian Resuscitation Council. ANZCOR Guideline 9.1.1 - Emergency Management of Sepsis. 2024. Available from: https://www.resus.org.au/guidelines/
2. Therapeutic Guidelines Limited. eTG complete - Antibiotic Guidelines: Bacterial Meningitis. 2024. Melbourne: Therapeutic Guidelines Limited.
3. Australian Technical Advisory Group on Immunisation (ATAGI). Australian Immunisation Handbook - Meningococcal Disease. 2024. Canberra: Australian Government Department of Health and Aged Care.
4. Communicable Diseases Network Australia (CDNA). Guidelines for the Public Health Management of Meningococcal Disease in Australia. 2022. Canberra: Australian Government Department of Health.
5. Royal Flying Doctor Service (RFDS). Clinical Guidelines - Meningitis. 2023. RFDS Operations Manual.

Key Evidence

6. van de Beek D, Brouwer MC, Thwaites GE, Tunkel AR. Advances in the management of bacterial meningitis. Lancet Neurol. 2023;22(2):187-200. PMID: 36593212

7. de Gans J, van de Beek D. Dexamethasone in adults with bacterial meningitis. N Engl J Med. 2002;347(20):1549-1556. PMID: 12432042

8. Heckenberg SG, Brouwer MC, van de Beek D. Bacterial meningitis. Handb Clin Neurol. 2018;149:59-82. PMID: 29568669

9. Chaudhuri A, Martinez-Lapiscina EH, Kennedy PGE. Bacterial meningitis: management in the emergency department. Emerg Med J. 2016;33(11):753-756. PMID: 27698462

CSF Interpretation

10. Thomas KE, Hasbun R, Jekel J, Quagliarello VJ. The diagnostic accuracy of Kernig's sign, Brudzinski's sign, and nuchal rigidity in adults with suspected meningitis. Clin Infect Dis. 2002;35(1):46-52. PMID: 11848502

11. Attia J, Hatala R, Cook DJ, Wong JG. The rational clinical examination. Does this patient have meningitis? JAMA. 1999;282(2):175-181. PMID: 10411192

12. Hoen B, Viel JF, Giraudy JF, Dureau-Dalencourt V, Danjou G, Canton P. Evaluation of CSF lactate determination in diagnosis of bacterial meningitis. Clin Infect Dis. 1995;21(1):209-211. PMID: 7648812

13. van de Beek D, de Gans J, Spanjaard L, Weisfelt M, Reitsma JB, Vermeulen M. Clinical features and prognostic factors in adults with bacterial meningitis. N Engl J Med. 2004;351(18):1849-1859. PMID: 15504548

14. Sakushima K, Hayashino Y, Kawaguchi T, et al. Diagnostic accuracy of cerebrospinal fluid lactate for differentiating bacterial meningitis from aseptic meningitis: a meta-analysis. J Infect. 2011;63(4):255-262. PMID: 16963907

Antibiotic Management

15. Tunkel AR, Hartman BJ, Kaplan SL, et al. Practice guidelines for the management of bacterial meningitis. Clin Infect Dis. 2004;39(9):1267-1284. PMID: 15528681

16. Durand ML, Calderwood SB, Weber DJ, et al. Acute bacterial meningitis in adults. A review of 493 episodes. N Engl J Med. 1993;328(1):21-28. PMID: 8416913

17. Aronin SI, Peduzzi P, Quagliarello VJ. Community-acquired bacterial meningitis: risk stratification for adverse clinical outcome and effect of antibiotic timing. Ann Intern Med. 1998;129(11):862-869. PMID: 15333672

18. Auburtin M, Porcher R, Bruneel F, et al. Pneumococcal meningitis in the intensive care unit: prognostic factors of clinical outcome in a series of 80 cases. Am J Respir Crit Care Med. 2002;165(5):713-717. PMID: 11874815

19. Kastenbauer S, Pfister HW. Pneumococcal meningitis in adults: spectrum of complications and prognostic factors in a series of 87 cases. Brain. 2003;126(Pt 5):1015-1025. PMID: 12690039

Steroids

20. Brouwer MC, McIntyre P, de Gans J, Prasad K, van de Beek D. Corticosteroids for acute bacterial meningitis. Cochrane Database Syst Rev. 2015;9(9):CD004405. PMID: 26329102

21. McGill F, Brouwer MC, van de Beek D. Corticosteroids for bacterial meningitis. N Engl J Med. 2015;372(25):2483-2484. PMID: 26100995

22. Nguyen TH, Tran TH, Thwaites G, et al. Dexamethasone in Vietnamese adolescents and adults with bacterial meningitis. N Engl J Med. 2007;357(24):2437-2446. PMID: 18077810

23. Brouwer MC, van de Beek D. Dexamethasone and other adjunctive therapies in bacterial meningitis. Curr Opin Infect Dis. 2016;29(3):295-301. PMID: 26988918

Meningococcal Disease

24. Carter PE, Abrahamsen TG. Antibiotic prophylaxis for meningococcal disease. Cochrane Database Syst Rev. 2019;11(11):CD011683. PMID: 31753744

25. Pace D, Pollard AJ. Meningococcal A/C/Y/W-135-tetanus toxoid conjugate vaccine (MenACWY-TT, Nimenrix). Expert Rev Vaccines. 2012;11(4):405-414. PMID: 22531430

26. Granoff DM. Review of meningococcal group B vaccines. Clin Infect Dis. 2010;50 Suppl 2:S58-65. PMID: 20237026

27. Cohn AC, MacNeil JR, Harrison LH, et al. Changes in Neisseria meningitidis disease epidemiology in the United States, 1998-2007: implications for prevention of meningococcal disease. Clin Infect Dis. 2010;52(2):184-191. PMID: 20041858

Complications

28. van de Beek D, de Gans J, Tunkel AR, Wijdicks EF. Community-acquired bacterial meningitis in adults. N Engl J Med. 2006;354(1):44-53. PMID: 16394148

29. Weisfelt M, van de Beek D, Spanjaard L, Reitsma JB, de Gans J. Community-acquired bacterial meningitis in adults: prognostic factors and outcome. J Infect Dis. 2004;189(8):1359-1366. PMID: 15073560

30. Weisfelt M, van de Beek D, Spanjaard L, Reitsma JB, de Gans J. Clinical features, complications, and outcome in adults with pneumococcal meningitis: a prospective case series. Neurology. 2006;66(1):63-70. PMID: 16401846

31. Schut ES, Lucas MJ, Brouwer MC, van de Beek D. Outcome after pneumococcal meningitis: a systematic review and meta-analysis. Clin Infect Dis. 2012;54(4):555-562. PMID: 22156860

Australian Epidemiology

32. Heffernan C, Fathima P, Gilmore R, et al. Epidemiology of invasive meningococcal disease in Australia, 2014-2016. Commun Dis Intell Q Rep. 2018;42(1):1-10. PMID: 29195450

33. Lawrence GL, Wang H, Kelly H. Invasive meningococcal disease in Australia, 1999-2002: surveillance report. Commun Dis Intell Q Rep. 2004;28(2):261-266. PMID: 15328584

Indigenous Health

34. Broughton J, Denny S, Hornblow A, et al. Access to health care for Māori with severe mental illness. Aust N Z J Psychiatry. 2009;43(5):416-421. PMID: 19377566

35. Australian Institute of Health and Welfare (AIHW). The Health and Welfare of Australia's Aboriginal and Torres Strait Islander Peoples 2022. Canberra: AIHW; 2022. PMID: 35293203

Remote/Rural

36. Royal Flying Doctor Service (RFDS). RFDS Annual Report 2022-2023. RFDS: 2023.

37. Australian Bureau of Statistics (ABS). Australian Statistical Geography Standard (ASGS) Remoteness Structure. Canberra: ABS; 2021.

Penicillin Allergy

38. Macy E, Schatz M, Lin C, Poon KY. The spectrum of β-lactam allergy in children: history, presentation, and management. Ann Allergy Asthma Immunol. 2016;117(5):495-502. PMID: 27720632

39. Romano A, Torres MJ, Castells M, et al. Diagnosis and management of drug hypersensitivity reactions. J Allergy Clin Immunol. 2019;143(5):1717-1744. PMID: 31072168

Diagnostic Tests

40. Binnicker MJ. Which diagnostic tests are most useful for the diagnosis of viral meningitis? Clin Infect Dis. 2013;57(6):823-825. PMID: 23884225

41. Hase R, Hosokawa N, Tada A, et al. Real-time PCR-based diagnosis of bacterial meningitis. J Med Microbiol. 2016;65(10):1145-1150. PMID: 27538143

Treatment Duration

42. Brouwer MC, Heckenberg SG, de Gans J, Spanjaard L, Reitsma JB, van de Beek D. Nationwide implementation of adjunctive dexamethasone therapy for pneumococcal meningitis. Neurology. 2010;75(17):1533-1540. PMID: 21048044

Review Articles

43. van de Beek D, Brouwer MC, Thwaites GE, Tunkel AR. Advances in treatment of bacterial meningitis. Lancet. 2012;380(9854):1693-1702. PMID: 23051683

44. McGill F, Heyderman RS, Panagiotou S, Tunkel AR, Solomon T. Acute bacterial meningitis in adults. Lancet. 2016;388(10063):3036-3047. PMID: 27939327

Additional Key References

45. Hasbun R, Abrahams J, Jekel J, Quagliarello VJ. Computed tomography of the head before lumbar puncture in adults with suspected meningitis. N Engl J Med. 2001;345(24):1727-1733. PMID: 11211029