Two cases of proteasome inhibitors related thrombotic microangiopathies and literature review

Background Multiple myeloma (MM) is a prevalent hematological malignancy, with proteasome inhibitors (PIs) playing a crucial role in its therapeutic management. Although PIs are generally well-tolerated and associated with relatively mild side effects, recent evidence has increasingly drawn attention to proteasome inhibitor-related thrombotic microangiopathy (PI-related TMA). Case presentation Here, we report two clinical cases of PI-related TMA, highlighting the diagnostic process and subsequent management strategies. Confirmation of PI-related TMA prompted the discontinuation of the offending agent and consideration of plasma exchange therapy, which proved beneficial in selected patients. These case reports further facilitate a detailed discussion regarding the underlying pathogenic mechanisms and potential therapeutic approaches for PI-related TMA in MM. Conclusion The diagnosis of PI-related TMA in MM patients poses significant challenges due to overlapping clinical features between MM itself and TMA. The condition often presents insidiously but carries a severe prognosis, underscoring the necessity for prompt diagnosis and immediate therapeutic intervention.