Most common thrombophilias and diagnostic laboratory studies.
| . | Thrombophilia . | Laboratory Tests . |
|---|---|---|
| *if thrombophilic defect strongly suspected and level I testing is normal | ||
| Level I Testing | Factor V Leiden mutation | Polymerase chain reaction or screening with clotting assay |
| Prothrombin 20210 mutation | Polymerase chain reaction | |
| Antithrombin deficiency | Chromogenic or clotting assay | |
| Protein C deficiency | Chromogenic or clotting assay | |
| Protein S deficiency | Clotting assay or immunologic assay of free and total protein S antigen | |
| Hyperhomocystenemia | Fasting homocysteine | |
| Elevated lipoprotein (a) | ELISA | |
| Antiphospholipid antibodies | Phospholipid-based clotting assays, (PTT, DRVVT or Staclot LA) with confirmatory assay using exogenous phospholipid, ELISA assays for IgG and IgM antibodies directed against cardiolipin and β2 glycoprotein | |
| Elevated factor VIII | One-stage clotting assay, chromogenic assay | |
| Level II Testing* | Dysfibrinogenemia | Clotting assay (Clauss method), immunologic assay, thrombin time |
| Elevated factor IX, XI | One-stage clotting assay | |
| . | Thrombophilia . | Laboratory Tests . |
|---|---|---|
| *if thrombophilic defect strongly suspected and level I testing is normal | ||
| Level I Testing | Factor V Leiden mutation | Polymerase chain reaction or screening with clotting assay |
| Prothrombin 20210 mutation | Polymerase chain reaction | |
| Antithrombin deficiency | Chromogenic or clotting assay | |
| Protein C deficiency | Chromogenic or clotting assay | |
| Protein S deficiency | Clotting assay or immunologic assay of free and total protein S antigen | |
| Hyperhomocystenemia | Fasting homocysteine | |
| Elevated lipoprotein (a) | ELISA | |
| Antiphospholipid antibodies | Phospholipid-based clotting assays, (PTT, DRVVT or Staclot LA) with confirmatory assay using exogenous phospholipid, ELISA assays for IgG and IgM antibodies directed against cardiolipin and β2 glycoprotein | |
| Elevated factor VIII | One-stage clotting assay, chromogenic assay | |
| Level II Testing* | Dysfibrinogenemia | Clotting assay (Clauss method), immunologic assay, thrombin time |
| Elevated factor IX, XI | One-stage clotting assay | |