Summary

Bacterial Meningitis is a life-threatening medical emergency caused by bacterial infection of the leptomeninges (arachnoid and pia mater) and subarachnoid space. The classic triad of fever, neck stiffness, and altered mental status is present in <50% of adults; sensitivity increases with headache and photophobia. The most common pathogens in adults are Streptococcus pneumoniae and Neisseria meningitidis. Mortality remains high (10-30%) despite antibiotics. Immediate treatment involves empirical IV Ceftriaxone (plus Amoxicillin if Listeria risk) and Dexamethasone (to reduce neurological sequelae). Lumbar Puncture (LP) is diagnostic but must be deferred if signs of raised intracranial pressure (ICP) are present.

Key Facts

• Mortality: 10% for Meningococcal; 30% for Pneumococcal.
• Time-Critical: Delay in antibiotics > 1 hour increases mortality significantly.
• Classic Signs: Kernig's and Brudzinski's signs have low sensitivity (5-30%) but high specificity.
• Rash: Non-blanching petechial/purpuric rash suggests Meningococcal cause (not seen in Pneumococcal).
• Prophylaxis: Ciprofloxacin for close contacts of N. meningitidis.
• Steroids: Dexamethasone MUST be given with or just before first antibiotic dose to be effective.

Clinical Pearls

"Don't wait for the rash": The rash is a late sign of septicaemia. If you suspect meningitis, treat immediately.

"CT before LP?": You only need a CT head before LP if: GCS < 12, Focal Neuro Signs, Seizures, or Immunocompromised. Otherwise, LP immediately (don't delay for scan).

"The Golden Hour": If there is any delay in hospital transfer (>30-60 mins) in suspected meningococcal disease, give IM Benzylpenicillin in the community.

"Treat the Contacts": One case of meningococcal meningitis in a student halls of residence is a public health emergency. Prophylax the corridor/flatmates.

         SUSPECTED BACTERIAL MENINGITIS
                     ↓
        ASSESS AIRWAY, BREATHING, CIRCULATION
        - High flow oxygen
        - IV Access x 2
                     ↓
        CONTRAINDICATIONS TO IMMEDIATE LP?
        (GCS<12, Focal signs, Shock, Rash)
           /                   \
        YES                     NO
         ↓                       ↓
    START ANTIBIOTICS       LUMBAR PUNCTURE
    + STEROIDS NOW               ↓
         ↓                  START ANTIBIOTICS
      CT HEAD               + STEROIDS
         ↓
    LP IF SAFE LATER

1. Acute Medical Management

• First Line: IV Ceftriaxone 2g BD (or Cefotaxime 2g QDS).
  • Crosses BBB effectively.
• Add Amoxicillin 2g 4-hourly: If age > 50, pregnant, or immunocompromised (Covers Listeria monocytogenes).
• Add Dexamethasone 10mg QDS:
  • Give WITH or 15 mins BEFORE first antibiotic dose.
  • Continue for 4 days if Pneumococcal confirmed.
  • Stop if Meningococcal (less benefit, but usually given initially).
• Fluid Resuscitation: Treat septic shock aggressively.

2. Prophylaxis for Contacts

Indicated for close contacts (household, kissing contacts) of patients with Meningococcal disease (Not Pneumococcal).

• Ciprofloxacin 500mg PO stat dose (Adults).
• Rifampicin 600mg BD for 2 days (Alternative).
• Ceftriaxone 250mg IM stat (Pregnancy).

3. Public Health

• Notification: Bacterial Meningitis is a Notifiable Disease in the UK. Inform UKHSA immediately.

For Parents and Clinicians. Meningococcal septicaemia causes a non-blanching rash due to bleeding into the skin (vasculitis).

• Technique: Press a clear glass tumbler firmly against the rash.
• Blanching: If the redness disappears under pressure -> Viral/Heat rash.
• Non-Blanching: If you can still see the red spots through the glass -> Medical Emergency.
• Locations: Check everywhere, including soles of feet, palms, and conjunctiva.
• Note: In dark skin, the rash may be harder to see. Look at lighter areas (palms/soles).

Why do they go deaf? Bacteria spread from the subarachnoid space into the inner ear via the cochlear aqueduct. This causes suppressive labyrinthitis, ossification of the cochlea, and permanent deafness.

• Incidence: 30% of Pneumococcal meningitis survivors.
• Prevention: Dexamethasone reduces risk significantly.
• Screening: All patients requires Audiology assessment (Pure Tone Audiometry) within 4-6 weeks of discharge.
• Management: Cochlear implants if profound loss (Must be done quickly before cochlear ossification makes it impossible).

Key Guidelines

• NICE NG240 (Meningitis): Comprehensive guideline (2024 update).
• Joint Specialist Societies: UK Guideline for Adult Meningitis.

Key Trials

• De Gans et al. (NEJM 2002): Dexamethasone in Pneumococcal Meningitis.
  • Reduced mortality (15% vs 34%).
  • Reduced hearing loss.
  • Established steroids as standard of care.

What is Meningitis?

It is the swelling of the protective lining around the brain and spinal cord, usually caused by a bacteria or virus. Bacterial meningitis is much more dangerous than viral meningitis.

What are the signs?

• Severe headache.
• Stiff neck (can't assume chin to chest).
• Dislike of bright lights using.
• A rash that doesn't fade when you press a glass on it.

How is it treated?

It is an emergency. Patients need strong antibiotics into a vein immediately. They also get steroid injections to reduce brain swelling. Most people stay in hospital for at least 1-2 weeks.

Is it contagious?

• Meningococcal: Yes, spread by kissing/coughing. Close contacts (same house) prevention tablets.
• Pneumococcal: No, generally not contagious.