A 7 year-old female spayed Pembroke Welsh Corgi was presented to a veterinary teaching hospital for evaluation of acute onset generalized clonic-tonic seizures, obtunded mentation and petechiation. Her primary veterinarian previously saw the dog two days ago when she developed anorexia. Multiple petechiations were noted on her skin at that time. Her initial blood work revealed severe thrombocytopenia at 5-10 K/uL (RI, 190-450 K/uL). The rest of the work-up (thoracic/abdominal radiographs and tick-borne disease testing) was unremarkable, and she was prescribed prednisone for suspected primary immune-mediated thrombocytopenia (ITP). The following day, she developed two clonic-tonic generalized seizures that lasted 1-2 minutes each. Her mentation became progressively worse, and she had several seizures on the day of presentation to the teaching hospital.
