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Differential diagnosis of thrombocytopenia in the intensive care unit |
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| Differential diagnosis |
Approximate relative incidence |
Additional diagnostic clues |
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| Sepsis |
52% |
Positive (blood) cultures, positive sepsis criteria, hematophagocytosis in bone marrow aspirate |
| DICa |
25% |
Prolonged aPTT and PT, increased fibrin split products, low levels of physiological anticoagulant factors (antithrombin, protein C) |
| Massive blood loss |
8% |
Major bleeding, low hemoglobin, prolonged aPTT and PT |
| Thrombotic microangiopathy |
1% |
Schistocytes in blood smear, Coombs-negative hemolysis, fever, neurological symptoms, renal insufficiency |
| Heparin-induced thrombocytopenia |
1% |
Use of heparin, venous or arterial thrombosis, positive HIT test (usually ELISA for heparin-platelet factor IV antibodies), rebound of platelets after cessation of heparin |
| Immune thrombocytopenia |
3% |
Anti-platelet antibodies, normal or increased number of megakaryocytes in bone marrow aspirate, thrombopoeitin decreased |
| Drug-induced thrombocytopenia |
10% |
Decreased number of megakaryocytes in bone marrow aspirate or detection of drug-induced anti-platelet antibodies, rebound of platelet count after cessation of drug |
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Seven major causes of thrombocytopenia (platelet count <150 × 109/l) are listed. Relative incidences are based on two studies in consecutive intensive care unit patients [1,6] but may vary depending on the population studied. Patients with hematological malignancies were excluded. aPatients with sepsis and disseminated intravascular coagulation (DIC) are classified as DIC. aPTT, activated partial thromboplastin time; ELISA, enzyme-linked immunosorbent assay; HIT, heparin-induced thrombocytopenia; PT, prothrombin time. | ||
Levi and Opal Critical Care 2006 10:222 doi:10.1186/cc4975 |
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