Real-world investigation of platelet apoptosis for mechanistic insights into severe immune thrombocytopenia and bleeding.

BACKGROUND

Given the low platelet counts in patients with immune thrombocytopenia (< 100 × 109/L) and its pathophysiological complexity, it remains both a diagnostic and therapeutic challenge. Routine platelet function tests could not be performed due to the extremely low counts in a patient with gastrointestinal bleeding.

KEY CLINICAL QUESTION: Can an unconventional approach to platelet investigation provide important insights into a case of severe thrombocytopenia of unknown origin?

CLINICAL APPROACH: The patient experienced repeated episodes of bleeding, including gastrointestinal bleeding, with platelet counts falling to critically low levels (< 10 × 109/L). The use of a Platelet Mitochondrial Depolarization Assay, using flow cytometry, provided clinically useful data before and after bortezomib treatment cycles. Circulating antiplatelet autoantibodies (IgG and IgM) specific for the glycoprotein Ib and IIb/IIIa receptors were also detected by a customized elisa, showing unexpected, selective changes in response to bortezomib treatment.

CONCLUSION

Our approach, integrating a Platelet Mitochondrial Depolarization Assay with ELISA, demonstrates how detection of platelet apoptosis and platelet-targeting antibodies, can complement clinical investigation in bleeding disorders that involve severe platelet dysfunction and thrombocytopenia.