Intracranial Infections - Encephalitis

Question 1

What is Encephalitis?

Answer 1

Inflammation of the brain - most commonly viral in UK.

Question 2

Aetiology of Viral Encephalitis (4).

Answer 2

HSV :

1. Children : HSV-1 (Cold Sores).
2. Neonates : HSV-2 (Genital Herpes).
3. VZV (Chickenpox), CMV (Immunodeficiency), EBV (Infectious Mononucleosis).
4. MMR (Vaccine?).

Question 3

HSV-1 Encephalitis (2).

Answer 3

1. 95% of Adult Cases.

2. Typically Temporal and Inferior Frontal Lobes.

Question 4

What is Autoimmune Encephalitis due to?

Answer 4

NMDA-Receptor Antibodies.

Question 5

Clinical Presentation of Encephalitis (6).

Answer 5

1. Altered Consciousness.
2. Altered Cognition.
3. Unusual Behaviour.
4. Acute Onset of Focal Neurological Symptoms e.g. Aphasia (Temporal Lobe).
5. Acute Onset of Focal Seizures.
6. Fever.

Question 6

Investigations of Encephalitis (5).

Answer 6

1. Lumbar Puncture - CSF : Viral PCR.
2. CT & MRI if Lumbar Puncture is Contraindicated : Petechiae Haemorrhages.
3. Swabs of other Areas.
4. HIV Testing in All Patients.
5. EEG : Lateralised Periodic Discharges at 2Hz.

Question 7

Management of Encephalitis (3).

Answer 7

1. Empirical IV Antiviral Medications - Aciclovir : HSV, VZV and Ganciclovir : CMV.
2. Repeat Lumbar Puncture before stopping antivirals.
3. Follow-Up, Support, Rehabilitation.

Question 8

Adverse Effects of Aciclovir (7).

Answer 8

1. Generalised Fatigue/Malaise.
2. GI Disturbance.
3. Photosensitivity/Urticarial Rash.
4. AKI.
5. Haematological Abnormalities.
6. Hepatitis.
7. Neurological Reactions.

Question 9

Complications of Encephalitis (10).

Answer 9

1. Lasting Fatigue and Prolonged Recovery.
2. Change in Personality/Mood.
3. Change in Memory/Cognition.
4. Learning Disability.
5. Headaches.
6. Chronic Pain.
7. Movement Disorders.
8. Sensory Disturbances.
9. Seizures.
10. Hormonal Imbalance.