A tale of two EEGs - Photic driving or photoparoxysmal discharge

A 29-year-old woman has a history of developmental delay and focal segmental glomerulosclerosis resulting in kidney failure. She underwent renal transplant which unfortunately failed, and is on hemodialysis as well as immunosuppression including tacrolimus. She was recently hospitalized for urosepsis requiring intensive treatment with vasopressors and multiple antibiotics. Soon after discharge, she was noted to have unstable gait, multifocal twitches, falls, and very brief episodes of staring or inattentiveness. She was readmitted. Her head CT was normal and lumbar puncture was negative. A bedside EEG was requested and showed an unusual response during photic stimulation.