Immune thrombocytopenia (ITP) is a heterogeneous autoimmune disorder characterized by decreased platelet counts and a variable propensity for bleeding. Significant strides have delineated the pathophysiologic mechanisms of ITP and led to new therapeutics. Despite these advances, 5% to 30% of patients persist with low platelet counts and/or ongoing bleeding. This review summarizes the current definitions and pathophysiology of refractory ITP, revisiting diagnostic realms and management strategies for these difficult-to-treat patients.

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