Priority Differential Diagnoses to Consider Based on Presentation
| Presentation | Always consider |
|---|---|
| Coma | Hypoglycaemia, drug toxicity, intracranial haemorrhage/SOL with brainstem herniation, non-convulsive status, functional unresponsiveness* |
| Acute ataxia/vertigo | Cerebellar stroke (haemorrhage/infarction) |
| Hemiparesis | Stroke† |
| Paraparesis | Spinal cord compression/stroke‡ |
| Quadriparesis | Spinal cord compression/stroke, brainstem infarction‡ |
| Acute severe headache | Subarachnoid haemorrhage, venous sinus thrombosis |
| Transient loss of consciousness | Cardiac syncope, transient CSF outflow obstruction, seizure |
| Status epilepticus | Non-epileptic attack disorder,* underlying cause for status? |
| Seizure, fever, dysphasia | (Herpes simplex) encephalitis |
| Meningism +/– rash, fever | Bacterial meningitis |
| Saddle anaesthesia, sphincter disturbance, back pain | Cauda equina compression |
| Monocular visual loss | Giant cell arteritis, optic neuritis, ‘ophthalmological causes’ |
| Homonymous hemianopia | Stroke† |
| New onset Horner's | Carotid dissection, apical lung tumour |
| IIIrd nerve palsy | Uncal herniation, aneurysm (typically PCoM) |
| VIth nerve palsy | SOL/raised ICP |
| Postural/morning headache | SOL/raised ICP |
* Functional presentations are included here not because they are intrinsically dangerous but because of the risk of iatrogenic harm from unnecessary drug treatment and/or intubation.
‡ Brainstem and spinal cord stroke more frequently has a stuttering onset so must still be considered in sub-acute presentations.