12th August 2024

A 23-year-old man presents to A&E with a 48 hour history of a severe headache and neck stiffness

A 23-year-old man presents to A&E with a 48 hour history of a severe headache and neck stiffness. His observations are normal, apart from a temperature of 37.9 degrees Celsius. His neurological examination is normal. A CT head is performed which is normal. A lumbar puncture is performed and the CSF is noted to be clear with an opening pressure of 26 cmH₂O. The blood culture and CSF cultures are negative at 48 hours. The CSF xanthochromia is also negative.

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