Patient clinical and laboratory data
| Patient No | Presenting signs and symptoms | SAH | CSF analysis | Rheumatology panel |
| 1 | Severe HA, photophobia, | CT, MRI | None* | Elevated ESR and CRP; remainder negative |
| 2 | Severe HA, blurred vision, extremity weakness | CSF, CT, MRI | SAH, mild protein elevation | Negative |
| 3 | Severe HA, seizures | CT, MRI | None | Negative |
| 4 | Severe HA | CT, MRI | Normal | Negative |
| 5 | Severe HA, visual field cut | None | Mild protein elevation | Negative |
| 6 | Severe HA, seizures | CSF, CT, MRI | SAH, mild protein elevation* | Negative |
| 7 | Severe HA | CSF, MRI | SAH, mild protein elevation | Negative |
| 8 | Severe HA | CSF, CT, MRI | SAH | None |
| 9 | Severe HA, confusion | CSF, CT, MRI | SAH, mild protein elevation | Negative |
| 10 | Severe HA, photophobia, blurred vision, extremity weakness | None | Normal* | Negative |
| 11 | Severe HA, seizures, blurred vision | MRI | None | None |
↵* Patient underwent brain biopsy.
CRP, C reactive protein; ESR, erythrocyte sedimentation rate; HA, headache; SAH, subarachnoid hemorrhage.