Concurrent Immune Thrombocytopenic Purpura (ITP) and Thrombotic Thrombocytopenic Purpura (TTP) with Underlying Antiphospholipid Syndrome

Background: Immune Thrombocytopenic Purpura (ITP) and Thrombotic Thrombocytopenic Purpura (TTP) are both conditions that lead to thrombocytopenia. It is crucial to recognize TTP because it significantly impacts the treatment options and the prognosis. In clinical practice, both corticosteroids and rituximab can be utilized to treat ITP and TTP. However, plasma exchange therapy is the first-line treatment specifically for TTP, while corticosteroids are strongly recommended as the first-line treatment for ITP. Antiphospholipid syndrome is an autoimmune disorder resulting in a hypercoagulable state and is rarely reported with TTP. Case Report: A 33-year-old woman with a history of chronic primary ITP presented in the second-trimester of pregnancy with HELLP (hemolysis, elevated liver enzymes, low platelet count) syndrome requiring an emergency cesarean delivery. Following the delivery, she required continued prednisone for treatment. Four years later, she presented with acute neurological deficits and a platelet count of 5,000 per microliter. A critically low activity of ADAMTS13 and the presence of autoantibodies targeting ADAMTS13 led to a definitive diagnosis of TTP. Despite her neurological deficits resolving within 45 minutes, a magnetic resonance imaging of her brain showed small subacute punctate ischemic strokes. Her labs were positive for antiphospholipid syndrome. She was treated with dexamethasone, intravenous immunoglobulin, plasmapheresis, rituximab, prednisone, low molecular weight heparin and caplacizumab-yhdp. She was discharged on warfarin for life. Conclusion: Conducting systematic testing for ADAMTS13 activity and anti-ADAMTS13 antibodies in patients who exhibit neurological symptoms alongside thrombocytopenia while also screening for antiphospholipid antibodies may significantly enhance the diagnosis and management of this rare but serious combination of thrombotic conditions.