COMPREHENSIVE GENOTYPE AND PHENOTYPE CHARACTERIZATION IN NON-SEVERE HEMOPHILIA A PATIENTS ON ASSAY DISCREPANCIES.

SUELDO, E; ROSSETTI CL; ZIEGLER, BM; MARCHIONE VD; RADIC CP; ABELLEYRO, MM; DE BRASI CD; BAQUES, A; ARIAS, M

Londres

Congreso; XXX Congress of the International Society on Thrombosis and Haemostasis (ISTH); 2022

Background: One-third of patients with non-severe Hemophilia A (nsHA) presents a discrepancy between the results of FVIII activity (FVIII:C) measured by one-stage-assay (OSA) and chromogenic-substrate-assays (CSA). It is observed that this situation can lead to misunderstanding the diagnostic in Hemophilia A (HA) or even worst to get a wrong classification regarding the severity of the disease. Aims: Consider the impact of the discrepancies between OSA and CSA, to face the diagnostic and classification of Patients with Hemophilia and also evaluate the F8-genotype and phenotype.Methods: 111 patients having bleeding disorders with a diagnostic of HA between 2012 and 2021 were evaluated. We performed laboratory hemostasis studies in all samples (Prothrombin time, Activated Partial thromboplastin time (aPTT), Thrombin Time (TT), aPTT 1:1 mix, OSA, CSA, vWF:Ag, vWF:CoR, Siemens Healthineers; Sysmex CS-2500). The Initial classification of the disease was performed with OSA (Severe Hemophilia A: sHA