Table 2 Table 2
Test result | Cause |
|---|---|
PT prolonged, aPTT normal | Factor VII deficiency |
| Â | Mild vitamin K deficiency |
| Â | Mild liver insufficiency |
| Â | Low doses of vitamin K antagonists |
PT normal, aPTT prolonged | Factor VIII, IX, or XI deficiency |
| Â | Use of unfractionated heparin |
| Â | Inhibiting antibody and/or anti-phospholipid antibody |
| Â | Factor XII or prekallikrein deficiency (no relevance for in vivo coagulation) |
Both PT and aPTT prolonged | Factor X, V, II or fibrinogen deficiency |
| Â | Severe vitamin K deficiency |
| Â | Use of vitamin K antagonists |
| Â | Global clotting factor deficiency |
|  |    Synthesis: liver failure |
|  |    Loss: massive bleeding |
|  |    Consumption: DIC |