A Multi-Institution Retrospective Study to Assess Bleeding Phenotype Among Patients with Platelet Function Disorders

▪ Introduction: Platelet function disorders (PFD) clinically manifest with wide variability in mucocutaneous bleeding and significant hemorrhage post-surgery or trauma. The overall prevalence of PFD is not known, as there have not been large population-based studies. Treatment of these patients vary based on their bleeding phenotype. Additionally, the exact bleeding phenotype of many qualitative platelet defects are not well described in literature. This study aims to describe the bleeding phenotype among patients with different (PFD). Methods: This is a retrospective study among patients with PFD conducted at 3 Hemophilia Treatment centers - HOG Center for Bleeding and Clotting Disorders of CHOA, Children's Mercy hospital HTC and Rainbow babies & Children's hospital HTC. Institutional IRB approval was obtained at all 3 institutions. We collected data on demographics, bleeding symptoms at presentation, bleeding episodes, management of these bleeds over a 6-year time period (2015-2020). Results: We identified 131 patients with PFDs at 3 institutions. This included 67 males (51.2%) and 64 females (48.8%). Among 131 patients, 72 patients (55%) had a defect in platelet agonist interaction/receptor defect (ADP/Epinephrine/Collagen/TXA2/Arachidonic acid), 37 patients (28.2%) had delta storage pool defect, 8 patients (6.1%) had Glanzmann thrombasthenia, 7 patients (5.3%) had a platelet release defect, 3 patients (2.3%) with an alpha granule defect, 2 patients (1.5%) with Bernard Soulier syndrome and 1 patient (0.76%) with Wiskott Aldrich syndrome. The most common bleeding symptoms at presentation were epistaxis (40.4%), followed by easy bruising (31.3%), heavy menstrual bleeding (15.2%), gum bleeding (6.87%) and gastrointestinal bleeding (4.58%). From 2015-2020, a total of 162 bleeds were documented, and 68 patients (51.9%) with at least 1 documented episode of bleeding. 67.2% of these bleeds were spontaneous, 12.3% were secondary to trauma, 4.9% after a dental procedure, 2.5% after surgery and 0.6% after child birth. The most common type of bleeding episode in diagnosed patients included epistaxis (50%), heavy menstrual bleeding (17.9%), skin/soft tissue bleed (5.5%), gastrointestinal (5.5%) and dental/tooth related (4.9%). 93 bleeding episodes (57.4%) required some form of treatment in various settings - home (73%), clinic (15%), emergency room (7.5%), hospitalization (14%) and ICU stay (2%). Treatments included antifibrinolytics (68.8%), recombinant factor VII