Acquired platelet abnormalities include quantitative (thrombocytopenia) and qualitative (dysfunctional) defects. Quantitative platelet disorders include those caused by decreased platelet production (marrow infiltration, aplastic anemia, drugs, viral infections, and chronic alcohol use), and increased platelet destruction (idiopathic thrombocytopenic purpura (ITP), thrombotic thrombocytopenic purpura (TTP), hemolytic uremic syndrome, disseminated intravascular coagulation (DIC), viral infections, drugs and HELLP syndrome). Other causes include acute hemorrhage, hemodialysis and splenic sequestration. Qualitative platelet disorders are commonly associated with uremia, liver disease, DIC, drugs (aspirin, NSAIDs, clopidogrel), myeloproliferative disorders, and antiplatelet antibodies. Initial laboratory testing should include a CBC with peripheral smear.