(P-TA-2) Characterization and Management of Thrombocytosis in Sickle Cell Disease Patients Undergoing Red Blood Cell Exchange

Background/Case Studies: Anemia-associated thrombocytosis can lead to severe complications. Adult patients with sickle cell disease (SCD) may have a more pronounced platelet elevation due to functional asplenia. However, thrombocytosis in SCD has not been well characterized in the literature. We performed an institutional retrospective study to evaluate thrombocytosis in SCD patients receiving regular outpatient red blood cell exchanges (RBCEx) and reviewed the effectiveness of the management strategy for thrombocytosis in this setting.

Study

Design/Methods: Data from 63 adult SCD patients receiving RBCEx between January 2021 and March 2025 was retrospectively reviewed. The patients received long-term outpatient RBCEx at our institution every 6-8 weeks to keep their Hgb S level around 40-50%. Information collected included indication for RBCEx, hemoglobin (Hgb) level at thrombocytosis, and platelet count ( >450K/uL) along with corresponding clinical presentations and experience in managing thrombocytosis for patients undergoing long-term RBCEx.

Results/Findings: Summarized in the table 1

Conclusions: Thrombocytosis is a common finding in SCD patients. Over 50% of the patients with chronic thrombocytosis were found to have a history of thrombosis. Platelet elevation correlates with lower Hgb levels, and RBC treatment effectively corrects anemia and reduces platelet counts quickly. Regular RBCEx is a preferred option for patients on RBC long-term treatment to prevent persistent thrombocytosis. Further studies are needed to optimize anemia control by targeting appropriate post-exchange Hct levels.