PB0782 - The role of Immature Platelet Fraction in determining the need for transfusion and predicting thrombopoietic recovery in patients undergoing cytotoxic chemotherapy

Background: Chemotherapy often causes myelotoxicity, leading to a high risk of bleeding. To avoid complications, prophylactic platelet transfusions are frequently required.

Aims: Our study aims to investigate the correlation between the immature platelet fraction (IPF) and bleeding likelihood. Additionally, we aim to identify a threshold for anticipating bleeding risk and to assess the role of IPF in predicting thrombopoietic recovery.

Methods: This prospective study follows patients diagnosed with hematological malignancies, undergoing cytotoxic chemotherapy at Ibn Sina University Hospital. Hematological parameters were measured on the Sysmex XN-9000 analyzer. Patients were monitored daily for platelet count and IPF percentage, and were examined twice daily for bleeding.

Results: The study involved 45 patients, with a median age of 42 years and a male-to-female sex ratio of 2:1. Out of these patients, 26.7% had multiple myeloma and were scheduled for hematopoietic stem cell transplantation. The remaining 73.3% of patients were undergoing high-dose chemotherapy for various hemopathies. Among these patients, 64.4% were receiving their first therapeutic line, while 6.7% and 2.2% were receiving their second and third therapeutic lines respectively.
The recovery phase of thrombocytopenia was preceded by a rise in the IPF percentage, with a median of 4 days, before platelet recovery. The median length of aplasia was 9 days, with a median IPF rate of 26.1% at platelet recovery.
Patients with low IPF were at higher risk of bleeding (p < 0.001) with a cut-off of 0.79% (sensitivity 93.55%, specificity 85.71%, positive predictive value 93.55%, Youden’s index 0.79%, AUC 0.94). Also, the lowest IPF rates were linked to severe bleeding, equivalent to WHO grades 3 and 4 (p < 0.001).

Conclusion(s): We identified an optimal cutoff value of 0.79% for IPF to predict bleeding in patients undergoing cytotoxic chemotherapy, with an average time for thrombopoietic recovery of 4 days. Implementing these values in transfusion strategies may decrease prophylactic platelet transfusions.