Multifocal avascular necrosis in a patient with refractory immune thrombocytopenia and antiphospholipid antibodies; case report and review of literature.

Avascular necrosis (AVN) is a devastating condition that is rarely reported in patients with immune thrombocytopenia (ITP). Treatment with steroids remains a major risk factor for developing AVN. However, the incidence of AVN in patients with ITP requiring corticosteroid therapy is much less than that observed with other clinical conditions requiring corticosteroids. ITP is a bleeding disorder but can be also be a pro-thrombotic state via different mechanisms and thus could result in AVN. Among the possible causes of this pro-thrombotic state is the presence of antiphospholipid antibodies (aPLs). In this case, we report a patient with refractory ITP who developed multifocal AVN around the time she acquired new aPLs. We also discuss different mechanisms by which risk of thrombosis is increased in ITP and the relationship between ITP, aPLs and antiphospholipid syndrome.