Peripheral Blood Findings in Thrombocytopenic Disorders
Normal red blood cells (RBCs) and white blood cells (WBCs) | Drug-induced thrombocytopenia Hepatitis C–related thrombocytopenia HIV-related thrombocytopenia Posttransfusion purpura |
RBC fragmentation (schistocytes) | Disseminated intravascular coagulation (DIC) HELLP syndrome (hemolytic anemia, elevated liver enzymes, low platelets) Metastatic cancer Preeclampsia with DIC Thrombotic thrombocytopenic purpura Valvular hemolysis |
WBC abnormalities | Hypersegmented polymorphonuclear leukocytes in megaloblastic anemias Immature cells in large granular lymphocyte leukemia or increased mature lymphocytes in chronic lymphocytic leukemia Markedly diminished granulocytes in aplastic anemia |
Frequent giant platelets (approaching the size of RBCs) | Bernard-Soulier syndrome Disorders related to the myosin heavy chain 9, non-muscle gene (MYH9) Other congenital thrombocytopenias |
RBC abnormalities, nucleated RBCs, and immature granulocytes | |
Platelet clumping | Pseudothrombocytopenia |