| Complete blood count and reticulocyte count |
| Peripheral blood film |
| Liver function tests |
| Thyroid function tests |
| Quantitative immunoglobulin level measurement |
| Direct antiglobulin test |
| Antiphospholipid antibodies |
| ANA |
| H pylori |
| HIV |
| HCV |
| HBV |
| VWD type IIB testing* |
| Complete blood count and reticulocyte count |
| Peripheral blood film |
| Liver function tests |
| Thyroid function tests |
| Quantitative immunoglobulin level measurement |
| Direct antiglobulin test |
| Antiphospholipid antibodies |
| ANA |
| H pylori |
| HIV |
| HCV |
| HBV |
| VWD type IIB testing* |
ANA indicates antinuclear antibody.
Laboratory investigation of type IIB VWD may be indicated if there is a history of bleeding or family history of thrombocytopenia or if therapy for ITP is ineffective. First-tier tests will include VWF activity (VWF:RCo) and antigen, ristocetin-induced platelet aggregation, and multimeric analysis of VWF.