Spontaneous subarachnoid hemorrhage due to arteriovenous malformation mimicking migraine: A case report.

Subarachnoid hemorrhage (SAH) due to Arteriovenous Malformation (AVM) is a rare emergency case, which is often misdiagnosed as migraine. Here we present a case of SAH due to AVM that mimics migraine. A 41-year-old man came with headaches that radiated to the neck, worsened in the last week, accompanied by nausea, vomiting, photophobia, and a history of intermittent headaches for the previous 2 years. Physical examination was within normal limits, initial laboratory tests showed leukocytosis, and CT scan was not typical. The patient was diagnosed with migraine. Apparently, the lumbar puncture showed very high red blood cells, suspected as SAH. CT angiography revealed an extra-axial AVM. The patient was later diagnosed as SAH due to AVM. We recommend applying 4 key points, namely headache progressivity, neck pain, neck stiffness, and leukocytosis, to differentiate SAH due to AVM from migraine, especially in areas with limited facilities.