ACUTE SPINAL CORD INFARCTION IN THE SETTING OF HEREDITARY THROMBOTIC THROMBOCYTOPENIC PURPURA

Abstract

TOPIC: Critical Care TYPE: Medical Student/Resident Case Reports INTRODUCTION: Thrombotic thrombocytopenic purpura (TTP) is an acquired or inherited condition characterized by platelet aggregation and thrombosis due to an accumulation of von Willebrand factor multimers caused by decreased ADAMTS13 protease activity. It usually presents with fever, microangiopathic hemolytic anemia, thrombocytopenia, neurologic findings, and renal dysfunction. Acquired TTP is due to an inhibitory autoantibody against ADAMTS13 and is treated with glucocorticoids, rituximab, plasmapheresis, and caplacizumab [1]. Hereditary TTP is due to an autosomal recessive ADAMTS13 mutation and is treated with prophylactic and therapeutic plasma infusion [2]. Despite its prothrombotic nature, active bleeding at presentation is an uncommon complication described in literature. [3] We present an unusual case of hereditary TTP that caused acute spinal cord infarction from active bleeding into the spinal canal. CASE PRESENTATION: A 33-year-old female with past medical history of systemic lupus erythematosus presented with malaise, fevers, dyspnea, vomiting, and diarrhea. She was altered and febrile upon arrival, but then developed bleeding from the vagina, rectum, and bladder. TTP was empirically diagnosed based on fever, encephalopathy, and lab work (hemolysis, kidney injury, and thrombocytopenia). Blood product transfusions and plasmapheresis were initiated. Hereditary TTP was diagnosed based on decreased ADAMTS13 activity with negative inhibitor testing, so plasma infusions were started in lieu of plasmapheresis. During her hospitalization she exhibited progressive diffuse lower extremity weakness, sensory deficits, and absent deep tendon reflexes. MRI of the brain and spinal cord showed an infarction from C5 to the conus medullaris, as well as an extra-arachnoid fluid collection/hematoma throughout the dorsal canal from C3 to T12/L1. This was diagnosed as a subdural hematoma causing severe stenosis of the proximal and mid-thoracic canal. She was not a surgical candidate, so she was treated with plasma infusions and aggressive physical therapy. DISCUSSION: This case was challenging as TTP typically leads to thrombosis rather than bleeding, and the development of a spinal cord infarction is an unusual manifestation for TTP. Despite normal coagulation studies and negative active lupus studies, the patient's clinical presentation and decreased ADAMTS13 activity confirmed TTP even in the setting of significant bleeding. With acute spinal cord dysfunction, differential includes transverse myelitis, epidural abscess, infarction, and syringomyelia. MRI of the spine is diagnostic. TTP management must include platelet transfusion in the setting of active bleeding as it can be life saving.[3] CONCLUSIONS: TTP management differs on whether it is inherited or acquired. Although TTP is usually a prothrombotic entity, clinicians must keep it in the differential for active bleeding in the critically ill patient. REFERENCE #1: Scully M, Hunt BJ, Benjamin S, et al. Guidelines on the diagnosis and management of thrombotic thrombocytopenic purpura and other thrombotic microangiopathies. Br J Haematol 2012; 158:323. REFERENCE #2: Hamroun A, Prouteau C, Provôt F. Hereditary Thrombotic Thrombocytopenic Purpura. N Engl J Med 2020; 382:392. REFERENCE #3: Swisher KK, Terrell DR, Vesely SK, et al. Clinical outcomes after platelet transfusions in patients with thrombotic thrombocytopenic purpura. Transfusion 2009; 49:873. DISCLOSURES: No relevant relationships by Mohamed Hajmurad, source=Web Response No relevant relationships by Jonathan Hendrie, source=Web Response No relevant relationships by Hamza Khan, source=Web Response No relevant relationships by Daniel Matthews, source=Web Response