A patient with sudden severe headache described as "thunderclap" and neck stiffness; what is the most important initial test and concern?

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Multiple Choice

A patient with sudden severe headache described as "thunderclap" and neck stiffness; what is the most important initial test and concern?

Sudden, severe “thunderclap” headache with neck stiffness points to subarachnoid hemorrhage from a ruptured aneurysm, a medical emergency that requires rapid evaluation. The best first test is a noncontrast head CT as soon as possible, ideally within 6 hours of onset, because it quickly detects blood in the subarachnoid space. If the CT is negative but the suspicion remains high, perform a lumbar puncture to look for xanthochromia or red blood cells in the CSF, which can confirm SAH even when the CT misses it. This sequence is more appropriate than assuming meningitis, delaying workup with MRI, or giving symptomatic migraine treatment, because missing a subarachnoid hemorrhage has dire consequences and CT plus LP provides the most reliable, timely diagnosis.

Sudden, severe “thunderclap” headache with neck stiffness points to subarachnoid hemorrhage from a ruptured aneurysm, a medical emergency that requires rapid evaluation. The best first test is a noncontrast head CT as soon as possible, ideally within 6 hours of onset, because it quickly detects blood in the subarachnoid space. If the CT is negative but the suspicion remains high, perform a lumbar puncture to look for xanthochromia or red blood cells in the CSF, which can confirm SAH even when the CT misses it. This sequence is more appropriate than assuming meningitis, delaying workup with MRI, or giving symptomatic migraine treatment, because missing a subarachnoid hemorrhage has dire consequences and CT plus LP provides the most reliable, timely diagnosis.

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