Laboratory testing for BDUC
| . | Laboratory testing . | Comments . |
|---|---|---|
| Level 1 (initial screen for common causes of MBD) | FBC and blood film | Exclude thrombocytopenia/thrombocythemia, examine platelet morphology, consider other acquired hematologic causes such as myelodysplastic syndromes, leukemia, paraproteinemia; document any anemia especially iron deficiency |
| APTT/PT/ Clauss fibrinogen assay | Use sensitive reagents/instruments to critical factor deficiency below lower limit of normal | |
| VWF, factors VIII, IX, XI | VWF antigen (VWF: Ag) and function (ristocetin cofactor activity; VWF: Gp1bM and VWF collagen binding activity); if available, chromogenic FVIII assay to diagnose divergent one stage and chromogenic assays for mild haemophilia especially in men | |
| Platelet aggregation light transmission aggregometry (LTA) with arachidonic acid, ADP, adrenaline, collagen, thromboxane B2 agonist | According to ISTH LTA aggregation recommendations | |
| Platelet nucleotide assessment | To detect storage pool deficiency either by nucleotide assessment, mepacrine labeling of platelets by flow cytometry or electron microscopy | |
| ABO blood group | Blood group O is associated with reduced VWF level and with BDUC | |
| CRP | Ensure no occult inflammatory process could falsely elevate coagulation parameters into the normal range such as VWF | |
| Repeat | To confirm abnormal results and establish MBD diagnosis | |
| Level 2 (for rarer causes of MBD) | Rare clotting factor deficiency (FXIII activity and antigen, FII, FV, VII, FX) | |
| Level 3 (specialized or research assays) | PFA-200 assay; platelet flow cytometry with monoclonal antibodies and activation markers, platelet electron microscopy, platelet genomics | Platelet focused laboratory in close proximity to patients (except platelet genomics) |
| Disorders of fibrinolysis (euglobulin clot lysis time, plasminogen activator inhibitor-1 activity/tissue Ppasminogen activator antigen, α2 antiplasmin activity) | Depending on local laboratory practice and expertise | |
| Global assays such as thrombin generation, plasma clot lysis, thromboelastography | Research only | |
| Specialized assays for thrombomodulin, factor V bleeding mutation (east Texas, Amsterdam), tissue factor deficiency (heterozygous), other platelet function disorders (Scott syndrome, Quebec bleeding disorder) | Research only |
| . | Laboratory testing . | Comments . |
|---|---|---|
| Level 1 (initial screen for common causes of MBD) | FBC and blood film | Exclude thrombocytopenia/thrombocythemia, examine platelet morphology, consider other acquired hematologic causes such as myelodysplastic syndromes, leukemia, paraproteinemia; document any anemia especially iron deficiency |
| APTT/PT/ Clauss fibrinogen assay | Use sensitive reagents/instruments to critical factor deficiency below lower limit of normal | |
| VWF, factors VIII, IX, XI | VWF antigen (VWF: Ag) and function (ristocetin cofactor activity; VWF: Gp1bM and VWF collagen binding activity); if available, chromogenic FVIII assay to diagnose divergent one stage and chromogenic assays for mild haemophilia especially in men | |
| Platelet aggregation light transmission aggregometry (LTA) with arachidonic acid, ADP, adrenaline, collagen, thromboxane B2 agonist | According to ISTH LTA aggregation recommendations | |
| Platelet nucleotide assessment | To detect storage pool deficiency either by nucleotide assessment, mepacrine labeling of platelets by flow cytometry or electron microscopy | |
| ABO blood group | Blood group O is associated with reduced VWF level and with BDUC | |
| CRP | Ensure no occult inflammatory process could falsely elevate coagulation parameters into the normal range such as VWF | |
| Repeat | To confirm abnormal results and establish MBD diagnosis | |
| Level 2 (for rarer causes of MBD) | Rare clotting factor deficiency (FXIII activity and antigen, FII, FV, VII, FX) | |
| Level 3 (specialized or research assays) | PFA-200 assay; platelet flow cytometry with monoclonal antibodies and activation markers, platelet electron microscopy, platelet genomics | Platelet focused laboratory in close proximity to patients (except platelet genomics) |
| Disorders of fibrinolysis (euglobulin clot lysis time, plasminogen activator inhibitor-1 activity/tissue Ppasminogen activator antigen, α2 antiplasmin activity) | Depending on local laboratory practice and expertise | |
| Global assays such as thrombin generation, plasma clot lysis, thromboelastography | Research only | |
| Specialized assays for thrombomodulin, factor V bleeding mutation (east Texas, Amsterdam), tissue factor deficiency (heterozygous), other platelet function disorders (Scott syndrome, Quebec bleeding disorder) | Research only |