Laboratory investigation of neonatal coagulation disorders
| Condition | PT | APTT | Fibrinogen | Platelets | Diagnostic tests/other useful tests |
|---|---|---|---|---|---|
| PT, Prothrombin time; APTT, activated partial thromboplastin time; N, normal; DIC, disseminated intravascular coagulation; FII, FVII, FIX, FX, FXI, and FXII, factor II, VII, IX, X, XI, and XII; vWD, von Willebrand disease; vWF, von Willebrand factor. | |||||
| Inherited disorders | |||||
| Haemophilia A | N | ↑ | N | N | FVIII assay |
| Haemophilia B | N | ↑ | N | N | FIX assay |
| vWD (type III) | N | ↑ | N | N/↓ | FVIII/vWF assays |
| FVII | ↑ | N | N | N | FVII assay |
| FX | ↑ | ↑ | N | N | FX assay |
| Fibrinogen | N/↑ | N/↑ | ↓ | N | Fibrinogen assay |
| FXIII | N | N | N | N | FXIII screen/assay |
| Acquired disorders | |||||
| DIC | ↑ | ↑ | ↓ | ↓ | d-Dimers |
| Vitamin K deficiency | ↑ | N/↑ | N | N | FII, VII, IX, X |
| Liver disease | ↑ | ↑ | N/↓ | N/↓ | Factor assays |