Table 3.

Differential Diagnosis of Primary Immune Thrombocytopenia

Non-immunologic	Immunologic (Secondary immune thrombocytopenia
Decreased platelet production	Autoimmune disorders
• Acute or chronic leukemia	• Systemic lupus erythematosus
• Myelodysplasia	• Evans syndrome
• Aplastic anemia	• Antiphospholipid antibodies
• Congenital or acquired amegakaryocytic thrombocytopenia	Drug induced thrombocytopenia
• Toxic exposure (radiation, chemotherapy, alcohol)	• Antibiotics (Bactrim, Vancomycin, etc)
• Nutritional deficiency (B12, folate)	• Quinine
• Myelofibrosis	• Valproic Acid
• Myelopthistic processes	• Heparin
• Viral infection of hematopoietic precursors	• Others (oxaliplatin, alemtuzumab, purine analogues)
Enhanced platelet destruction	Infection
• Splenic sequestration	• H pylori
• Disseminated intravascular coagulation	• HIV
• Thrombotic thrombocytopenic purpura (no direct immune response to platelets)	• HCV
• Cardiopulmonary bypass	Lymphoproliferative disorders
• Infection/sepsis	Immunodeficiency (ALPS, CVID)
Inherited thrombocytopenia	Post transfusion purpura
	Vaccinations