Abstract 13493: Autoimmune Myopericarditis: A Rare Presentation of Acute Myeloid Leukemia

Abstract

Description of Case: A 51-year-old female with a past medical history of hypertension and type II diabetes mellitus presented with chest pain for 2 days that improved with sitting up and leaning forward. This was associated with exertional dyspnea and dizziness. EKG showed diffuse ST-T elevations with PR depression. The patient had a WBC Count of 1.37 X 10 9 /L, Troponin (normal 0.028 ng/ml) was 1.466>1.539>1.105>1.105, CRP 27.35 mg/ml, ESR was 77 mm/h. The patient’s symptoms were concerning for acute pericarditis versus acute coronary syndrome. Echocardiogram showed no regional wall motion abnormality and a small pericardial effusion. Cardiac magnetic resonance imaging demonstrated myopericarditis. The infectious workup was negative. Further workup showed positive antinuclear antibody and positive smooth muscle antibody/ribonucleoprotein. Flow cytometry indicated 1% blast with immunophenotypic atypia and neutropenia. Bone marrow aspiration and biopsy confirmed 6-7% myeloblast and pathology revealed high-grade myeloid neoplasm transforming into acute myeloid leukemia (AML). The patient was initiated on ibuprofen and colchicine for myopericarditis and is currently undergoing chemotherapy. Discussion: The etiology of pericarditis includes infection, malignancy, autoimmune disease, myocardial infarction, and cardiac surgery. In one study involving 784 patients, the etiology of pericarditis was only identified among 17% of cases, with 5% of those being autoimmune and 5% of those being neoplastic. Our patient had a rare presentation of AML and this case serves as a reminder to clinicians about the importance of thorough investigation when patients present with pericarditis without a clear attributable cause to identify an underlying disease and prevent treatment delay.