S2796 Warm Autoimmune Hemolytic Anemia Secondary to Acute Hepatitis B Virus Infection

Abstract

Introduction: Autoimmune hemolytic anemia (AIHA) is a rare extrahepatic manifestation, typically associated with HIV, hepatitis C, E, and Epstein Barr virus (EBV) infections. Hepatitis B virus (HBV) induced AIHA is an unusual association, not previously described in the literature. We report the first case of HBV-induced warm-AIHA, successfully treated with corticosteroids and anti-viral therapy. Case Description/Methods: A 67-year-old man presented to our hospital with one month of myalgias, arthralgias, and fatigue. He had no known history of the lymphoproliferative disorder, autoimmune disease, immunodeficiency, malignancy, or alcohol abuse. He lived in the woods and reported previous tick exposure and recent unprotected sexual encounters with multiple intravenous drug users. His physical examination revealed mild scleral icterus. Laboratory workup was notable for hemoglobin (Hb) 12.5 gm/dL, reticulocyte count 4.1%, elevated aspartate aminotransferase 493 units/L, alanine aminotransferase 693 units/L, total bilirubin 5.3mg/dL with indirect bilirubinemia 2.4 mg/dL, lactate dehydrogenase 1,158 units/L, and undetectable haptoglobin. Immunohematologic studies showed a direct antiglobulin test positive for IgG and C3 with isolation of warm autoantibodies by elution, consistent with a diagnosis of warm AIHA. Workup to elucidate the cause of AIHA including ANA, anti-proteinase-3, myeloperoxidase antibodies, peripheral blood smear, malaria smear, northeast tick panel, serum protein electrophoresis, and immunofixation were unrevealing. HIV, hepatitis A, C, E, and EBV infections were ruled out. HBV serologies revealed positive HBs-antigen, anti-HBc IgM, and PCR quantification HBV DNA 824,000,000 IU/ml, consistent with acute HBV infection. A diagnosis of warm AIHA secondary to acute HBV infection was made. 1mg/kg/day of prednisone and Tenofovir 25 mg/day were started. During the hospitalization, his anemia worsened, reaching a Hb nadir of 5.2 gm/dl and requiring ten units of packed red blood cell transfusions. He eventually stabilized at day 18, followed by a sustained virological response, clinical and laboratory remission of AIHA. Discussion: This case highlights AIHA as an unusual manifestation of acute HBV infection. An association between AIHA and hepatic viruses, including HIV, HCV, and EBV, has been well recognized. Acute HBV infection induced AIHA has not been reported in the literature yet. Therefore, clinicians should consider HBV infection in any patient presenting with new-onset AIHA of unclear etiology.Figure 1.: The patient's jaundice on physical exam.