Table 3 Representative underlying diseases and pathologies that must be differentiated

1.

Enhancement of platelet destruction and aggregation

• Thrombotic microangiopathy (TMA): thrombotic thrombocytopenic purpura (TTP), hemolytic uremic syndrome (HUS), HELLP syndrome, TMA after hematopoietic stem cell transplantation

• Heparin-induced thrombocytopenia (HIT)

• Idiopathic thrombocytopenic purpura (ITP), systemic lupus erythematosus (SLE), antiphospholipid antibody syndrome (APS)

• Extracorporeal circulation

2.

Pathologies that lead to bone marrow suppression/bone marrow failure

• Hematopoietic malignancies (acute leukemia, blastic crisis of chronic myelogenous leukemia, myelodysplastic syndrome, multiple myeloma, bone marrow infiltration of malignant lymphoma)

• Hemophagocytic syndrome

• Solid cancers (with bone marrow infiltration)

• Chemotherapy or radiation therapy with bone marrow suppression

• Bone marrow suppression due to drugs

• Some viral infections

• Some blood diseases besides hematopoietic malignancies (aplastic anemia, paroxysmal nocturnal hemoglobinuria, megaloblastic anemia)

3.

Liver failure, cirrhosis, hypersplenism

4.

Sepsis

5.

Bernard-Soulier syndrome, MYH9 disorder (e.g., May-Hegglin disorder), Wiskott-Aldrich syndrome

6.

Dilution

• Massive bleeding

• Massive transfusion, massive infusion

• Pregnancy thrombocytopenia

7.

Pseudo-thrombocytopenia

1. Thrombosis: deep vein thrombosis, pulmonary thromboembolism

2. Massive hydrothorax/ascites

3. Large hematoma

4. Fibrinolytic therapy

1. Congenital afibrinogenemia, congenital hypofibrinogenemia, dysfibrinogenemia

2. Liver failure, malnutrition

3. Drug-induced: L-asparaginase, corticosteroids, fibrinolytic therapy

4. False lowering: at the time of administration of drugs with anti-thrombin action (e.g., dabigatran)

1. Vitamin K deficiency, oral warfarin

2. Liver failure, malnutrition

3. Deficiency or inhibitor of extrinsic coagulation factor

4. Ingestion of a direct oral anticoagulant

5. False prolongation: insufficient blood sample volume, addition of an anti-coagulant

1. Liver failure, malnutrition

2. Extravasation due to inflammation (e.g., sepsis)

3. Degradation by granulocyte elastase (e.g., sepsis)

4. Congenital antithrombin deficiency

5. Drug-induced: L-asparaginase

1. Thrombosis: deep vein thrombosis, pulmonary embolism

2. Some atrial fibrillation