Meningitis and encephalitis — emergency viva

Opening stem

"A febrile student has headache, neck stiffness and a non-blanching rash. How do you manage him?"

Q1: Recognition and pathogens (2 min)

• Classic triad = fever + neck stiffness + altered mental status, complete in only 44 per cent (van de Beek 2004). 95 per cent have at least two of four: headache, fever, neck stiffness, AMS. NICE red-flag combination adds headache.^[1][2]
• Dutch 2006–2024 adult mix (Drost): pneumococcus 68 per cent, meningococcus 11 per cent, Listeria 6 per cent; overall mortality 17 per cent; Listeria 32 per cent.
• Purpura larger than 2 mm, or a spreading non-blanching rash, is a NICE meningococcal red flag; do not rule out if there is no rash.^[2]
• Encephalitis clues (personality change, seizures, focal signs) → consider HSV; NICE: do not routinely give aciclovir unless HSV encephalitis is strongly suspected.^[2]

Q2: First-hour management (2 min)

• Antibiotics within 1 hour of arrival: ceftriaxone at the highest BNF dose. UKHSA adult pre-hospital suspected IMD: 2 g IV/IM stat.^[2][4]
• Add IV amoxicillin when Listeria risk factors are present — not taught as a numbered age-50 cutoff.^[2]
• NICE does not list vancomycin as routine empiric cover.
• Dexamethasone 10 mg IV with or before the first dose (de Gans: 10 mg every 6 hours for 4 days; unfavourable RR 0.59, death RR 0.48). Still give if delayed less than 12 hours. Continue only for pneumococcus or Hib. Do not routinely steroid meningococcal disease.^[2][5]

Q3: LP, CT and CSF (2 min)

• Bloods, antibiotics and stabilisation before imaging.
• Do not LP if spreading purpura, GCS 9 or less, new focal neurology including seizures/posturing, or abnormal pupils.^[2]
• Hasbun features (age 60+, immunocompromise, CNS disease, seizure within a week, abnormal consciousness/focal findings): NPV 97 per cent if none.
• Dutch bacterial CSF medians: WCC 2400, protein 3.90 g/L, glucose 0.50 mmol/L. Blood cultures 76 per cent.

Q4: HSV, contacts, durations (2 min)

• When HSV is strongly suspected: Whitley acyclovir 30 mg/kg/day for 10 days; mortality 28 vs 54 per cent. Skoldenberg 10 mg/kg 8-hourly for 10 days; mortality 19 vs 50 per cent. Not an unsourced 14–21-day rule.^[3]
• Contacts: UKHSA ciprofloxacin 500 mg stat (12+) first-line; rifampicin 600 mg BD for 2 days alternative; IM ceftriaxone 250 mg (12+) if rifampicin cannot be offered. Cephalosporin-treated index case: no carriage dose.^[4]
• NICE stop-if-recovered: meningococcus 5 days, pneumococcus 10 days, Listeria 21 days amoxicillin/ampicillin.^[2]

Key phrases examiners want

• "Antibiotics within 1 hour; imaging never precedes the first dose if it would delay it."^[2]
• "Triad is fever, neck stiffness and AMS — only about 40 per cent complete."^[1]
• "Ciprofloxacin 500 mg once for close contacts aged 12 and over."
• "Aciclovir only if HSV encephalitis is strongly suspected; landmark trials were 10-day courses."

References5ShowHide

1. [1]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. New England Journal of Medicine, 2004.PMID 15509818
2. [2]National Institute for Health and Care Excellence. Meningitis (bacterial) and meningococcal disease: recognition, diagnosis and management NICE guideline NG240, 2024.Source
3. [3]Whitley RJ, Alford CA, Hirsch MS, Schooley RT, Luby JP, Aoki FY, Hanley D, Nahmias AJ, Soong SJ. Vidarabine versus acyclovir therapy in herpes simplex encephalitis. New England Journal of Medicine, 1986.PMID 3001520
4. [4]UK Health Security Agency. Guidance for public health management of meningococcal disease in the UK UKHSA, 2025.Source
5. [5]de Gans J, van de Beek D. Dexamethasone in adults with bacterial meningitis. New England Journal of Medicine, 2002.PMID 12432041