• Idiopathic thrombocytopenic purpura
• Thrombotic thrombocytopenic purpura
• Qualitative platelet disorders
• Bleeding, general approach

Decreased production (bone marrow disorder)

• Aplastic anemia
• Hematologic malignancies
• Myelodysplastic syndrome
• Megaloblastic anemia
• Chronic alcoholism
• Other infiltrative process, e.g., myelofibrosis, infection

Increased destruction

• Immune disorders
  • Idiopathic thrombocytopenic purpura
  • Drug-induced, e.g., heparin, sulfonamides, thiazides, quinine
  • Secondary (chronic lymphocytic leukemia, systemic lupus erythematosus)
  • Posttransfusion purpura
• Disseminated intravascular coagulation
• Thrombotic thrombocytopenic purpura
• Hemolytic uremic syndrome
• Sepsis
• Viral infections, AIDS
• Liver failure
• Preeclampsia-eclampsia

Splenic sequestration