PB1298 - Heavy menstrual bleeding is a common indication for evaluation for platelet disorders in adolescents.

Background: Inherited platelet disorders (IPD) including platelet function (PFD) or storage pool disorders (SPD) are heterogeneous and associated with variable bleeding phenotypes. Literature suggests a high prevalence of IPD in individuals presenting with heavy menstrual bleeding (HMB) but testing is variable.

Aims: Determine the prevalence of SPD and PFD in patients with HMB who are evaluated for IPD.

Methods: After IRB approval, a retrospective chart review of individuals with IPD testing was performed at a tertiary care pediatric institution. Individuals >10 years of age and of female biological sex were considered at risk for HMB. HMB presence was patient-reported, and severity was defined using the ISTH-BAT subscore. Data were analyzed using descriptive statistics, Mann-Whitney U, and Fisher’s exact tests. SPD was determined by electron microscopy and PFD by aggregometry.

Results: The mean age of individuals with HMB and tested for PFD was 15.4 years (range 10.7-21) and SPD was 15.6 years (range 11.9-21.5). Of females > 10 years of age, 54% reported HMB in the PFD evaluation cohort and 79% in the SPD evaluation cohort. PFD was diagnosed in 13/133 (9.8%) and SPD in 16/26 (61%) of at-risk patients with HMB that were evaluated. Of patients presenting with anemia and HMB, more were likely to be diagnosed with SPD compared to PFD (6/8 vs 5/55, respectively; p < 0.001). There was no difference between the overall BAT or HMB subscore in patients diagnosed with IPD versus not diagnosed.

Conclusion(s): HMB is a common indication for IPD testing. HMB with anemia is more prevalent in patients with SPD than PFD. Bleeding scores do not adequately discriminate between patients with and without an IPD diagnosis and therefore testing should be considered for adolescents presenting with HMB to ensure timely and accurate diagnosis.