Introduction

A 56 year-old man arrives to the emergency room with confusion. He is found to have anemia and thrombocytopenia and is referred to you for further evaluation.

A 68 year-old man with a background history of hypertension is admitted to hospital for removal of an asymptomatic pituitary tumor. He develops an acute pulmonary embolus on postoperative day 6, and then his platelet count starts to fall 5 days later. You are asked to see him to evaluate his thrombocytopenia.