PB1247 - High bleeding rates in delta-storage pool disease

Background: Δ-Storage pool disease (δ-SPD) is a heterogenous group of platelet function disorders caused by deficiency or reduced secretion of platelet dense granules. It is characterised by an increased mucocutaneous bleeding tendency and haemorrhage after surgery or delivery. The optimal strategy to prevent bleeding in δ-SPD is unknown.

Aims: To evaluate the efficacy of current preventive treatment in a cohort of patients with δ-SPD.

Methods: In a single center study, we retrospectively reviewed medical files of patients diagnosed with δ-SPD from 2016-2021. δ-SPD was confirmed using by determining platelet ADP concentrations. Data collection included all medical interventions around invasive diagnostic procedures, surgeries (minor and major) and deliveries (vaginal or caesarean section). Definition of bleeding complications were according to the ISTH bleeding scale criteria. Data on drug use and platelet transfusion were documented.

Results: A total of 85 procedures in 23 patients were included. Mean age of patients at inclusion was 39.8 (IQR 28-50), 15 (65.2%) were female. The average ADP measurement was 0.93 µmol/10^11 platelets (IQR 0.6-1.2). The most frequent procedures among 44 minor interventions were dental extractions (52.3%) and tonsillectomy (13.6%). Among 27 major interventions mostly abdominal (29.6%) and neurological surgery (22.2%) were documented. Bleeding occurred in 60% of the interventions in which no prophylaxis was given and in 22% of the cases in which any type of treatment was given. All bleeds were classified as non-major.
10 vaginal deliveries and 4 caesarean sections are documented. Five postpartum bleeding events occurred in 9 cases of vaginal delivery in which patients did not receive preventive treatment. In all 4 cases of caesarean section platelet transfusions were given and no bleeding was described.

Conclusion(s): In the majority of δ-SPD patients that received no preventive treatment strategy bleeding occurred during surgery. In addition, without prophylaxis, the incidence of postpartum haemorrhage was very high.