Central nervous system graft-versus-host disease in a 68-year-old man presenting with myoclonus

KEY POINTS A 68-year-old man presented to the emergency department with a 1-week history of sudden-onset myoclonus of his right leg. His medical history included allogeneic hematopoietic stem cell transplantation for myelodysplastic syndrome performed 742 days earlier, type 2 diabetes mellitus,