Differential diagnosis
The vast majority of headaches are benign, but when taking a history do not forget to ask about the following (early diagnosis can save lives):
Worrying features or ‘red flags’
• First and worst headache—subarachnoid haemorrhage.
• Thunderclap headache—subarachnoid haemorrhage.
• Unilateral headache and eye pain—cluster headache, acute glucoma.
• Unilateral headache and ipsilateral symptoms—migraine, tumour, vascular.
• Cough-initiated headache—increased ICP/venous thrombosis.
•Worse in the morning or bending forward—increase ICP/venous thrombosis.
• Persisting headache ± scalp tenderness in over-50s—giant cell arteritis.
• Headache with fever or neck stiff ness
Two other vital questions:
• Where have you been? (Malaria).
• Might you be pregnant? (Pre-eclampsia; especially if proteinuria and increase BP.)
Always examine a patient presenting with a severe headache; if nothing about history or examination is concerning, both you and the patient will be reassured, but subtle abnormalities are important not to miss.
Ref: OXFORD HANDBOOK OF CLINICAL MEDICINE. 10th edition.
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