Subdural hematoma in two hematopoietic stem cell transplant patients with post-dural puncture headache and initially normal CT brain scan.

Subdural hematoma (SDH) is a rare complication in patients after lumbar puncture. We report two patients receiving hematopoietic stem cell transplantation (HSCT) who developed post-dural puncture headache (PDPH) and SDH following intrathecal methotrexate (MTX). Both patients initially had normal computed tomography (CT) scan findings at the onset of headache. The diagnosis was established only when a repeat CT brain scan was performed for deteriorating neurological signs coinciding with improving platelet counts. These cases demonstrate the importance of continued vigilance for the early recognition of this salvageable entity. A normal initial CT finding and platelet count do not exclude the occurrence of SDH. A repeat CT scan, or even magnetic resonance imaging (MRI), are indicated if the clinical suspicion remains strong.