Neurology for AMC MCQ

A 19 year old university student is brought in with a 12-hour history of severe headache, fever, neck stiffness and photophobia. She is now drowsy and has a spreading non-blanching purpuric rash over her legs. Her blood pressure is 92/54 mmHg and her pulse is 124. A junior doctor wants to arrange a lumbar puncture before starting treatment. What is the most likely diagnosis?

1. Encephalitis Fever with altered behaviour, confusion, seizures or focal signs, pointing to brain rather than meningeal involvement. Fever, neck stiffness and a non-blanching purpuric rash with hypotension raises it.
2. Meningitis correct Correct. Fever, headache, neck stiffness, photophobia and a non-blanching purpuric rash is meningococcal meningitis with septicaemia.
3. Brain abscess Fever with focal signs and a space-occupying lesion on imaging. Fever, neck stiffness and a non-blanching purpuric rash with hypotension makes it worth considering.
4. Viral meningitis A similar but milder picture with a lymphocytic cerebrospinal fluid and a well patient. Fever, neck stiffness and a non-blanching purpuric rash with hypotension suggests it.
5. Sepsis (including neutropenic sepsis) Systemic sepsis from another source that can coexist or mimic. Fever, neck stiffness and a non-blanching purpuric rash with hypotension makes the source search matter.

The point: Bacterial meningitis is a notifiable emergency. It presents with fever, headache, neck stiffness and photophobia, and meningococcal disease adds a non-blanching petechial or purpuric rash. Do not delay antibiotics for investigations: give empirical intravenous ceftriaxone immediately, adding benzylpenicillin in the community before transfer, and dexamethasone with or just before the first dose to reduce neurological sequelae, particularly in pneumococcal disease. Add cover for Listeria with benzylpenicillin in the elderly, pregnant or immunocompromised. A lumbar puncture confirms the diagnosis, but a CT head comes first where there are signs of raised intracranial pressure, focal deficits, seizures or a reduced conscious level, and the antibiotics are never held for the scan. Notify the public health unit, and give clearance antibiotics such as ciprofloxacin to close contacts of meningococcal disease. The differential includes viral meningitis, encephalitis and subarachnoid haemorrhage.

Source: Therapeutic Guidelines (Australia) — Antibiotic: acute bacterial meningitis Therapeutic Guidelines (Australia) · tier 3, national formulary

A 19 year old university student is brought in with a 12-hour history of severe headache, fever, neck stiffness and photophobia. She is now drowsy and has a spreading non-blanching purpuric rash over her legs. Her blood pressure is 92/54 mmHg and her pulse is 124. A junior doctor wants to arrange a lumbar puncture before starting treatment. What is the most appropriate initial investigation?

1. Blood cultures and meningococcal PCR Taken before or alongside antibiotics to identify the organism. Fever, neck stiffness and a non-blanching purpuric rash with hypotension makes it necessary.
2. Blood glucose paired with cerebrospinal fluid glucose A low cerebrospinal fluid to blood glucose ratio supports a bacterial cause. Fever, neck stiffness and a non-blanching purpuric rash with hypotension makes it discriminating.
3. Lumbar puncture Confirms the diagnosis and identifies the organism, unless contraindicated by raised pressure. Fever, neck stiffness and a non-blanching purpuric rash with hypotension makes it central.
4. Notification to the public health unit Meningococcal disease is notifiable and triggers contact tracing. Fever, neck stiffness and a non-blanching purpuric rash with hypotension makes it a duty.
5. Immediate empirical antibiotics before investigations correct Correct. Antibiotics must not wait for a lumbar puncture; in suspected meningococcal disease with shock, any delay costs lives.

The point: Bacterial meningitis is a notifiable emergency. It presents with fever, headache, neck stiffness and photophobia, and meningococcal disease adds a non-blanching petechial or purpuric rash. Do not delay antibiotics for investigations: give empirical intravenous ceftriaxone immediately, adding benzylpenicillin in the community before transfer, and dexamethasone with or just before the first dose to reduce neurological sequelae, particularly in pneumococcal disease. Add cover for Listeria with benzylpenicillin in the elderly, pregnant or immunocompromised. A lumbar puncture confirms the diagnosis, but a CT head comes first where there are signs of raised intracranial pressure, focal deficits, seizures or a reduced conscious level, and the antibiotics are never held for the scan. Notify the public health unit, and give clearance antibiotics such as ciprofloxacin to close contacts of meningococcal disease. The differential includes viral meningitis, encephalitis and subarachnoid haemorrhage.

Source: Therapeutic Guidelines (Australia) — Antibiotic: acute bacterial meningitis Therapeutic Guidelines (Australia) · tier 3, national formulary

A 19 year old university student is brought in with a 12-hour history of severe headache, fever, neck stiffness and photophobia. She is now drowsy and has a spreading non-blanching purpuric rash over her legs. Her blood pressure is 92/54 mmHg and her pulse is 124. A junior doctor wants to arrange a lumbar puncture before starting treatment. What is the most appropriate next step in management?

1. Add benzylpenicillin in the community before transfer Pre-hospital penicillin for suspected meningococcal disease reduces mortality. Fever, neck stiffness and a non-blanching purpuric rash with hypotension makes it the field step.
2. Intensive care for a reduced conscious level or shock Escalation for the deteriorating or septic patient. Fever, neck stiffness and a non-blanching purpuric rash with hypotension makes it the safe choice.
3. Add Listeria cover in the elderly, pregnant or immunocompromised Benzylpenicillin added to cover Listeria in these groups. Fever, neck stiffness and a non-blanching purpuric rash with hypotension makes it targeted.
4. Clearance antibiotics for close contacts Ciprofloxacin or rifampicin for household and intimate contacts of meningococcal disease. Fever, neck stiffness and a non-blanching purpuric rash with hypotension makes it preventive.
5. Intravenous ceftriaxone immediately correct Correct. The empirical antibiotic for bacterial meningitis, given at once rather than after the scan or tap.

The point: Bacterial meningitis is a notifiable emergency. It presents with fever, headache, neck stiffness and photophobia, and meningococcal disease adds a non-blanching petechial or purpuric rash. Do not delay antibiotics for investigations: give empirical intravenous ceftriaxone immediately, adding benzylpenicillin in the community before transfer, and dexamethasone with or just before the first dose to reduce neurological sequelae, particularly in pneumococcal disease. Add cover for Listeria with benzylpenicillin in the elderly, pregnant or immunocompromised. A lumbar puncture confirms the diagnosis, but a CT head comes first where there are signs of raised intracranial pressure, focal deficits, seizures or a reduced conscious level, and the antibiotics are never held for the scan. Notify the public health unit, and give clearance antibiotics such as ciprofloxacin to close contacts of meningococcal disease. The differential includes viral meningitis, encephalitis and subarachnoid haemorrhage.

Source: Therapeutic Guidelines (Australia) — Antibiotic: acute bacterial meningitis Therapeutic Guidelines (Australia) · tier 3, national formulary