S5521 Symptoms, Serology, and Surprises of Acute Hepatitis B

Introduction: Acute hepatitis B (HBV) is transmitted via percutaneous or mucosal exposure to blood or body fluids including sexual contact, needle sharing, and perinatal transmission. Though U.S. incidence has declined due to vaccination, HBV remains a global health concern. High-risk groups include those with multiple sexual partners, men who have sex with men, injection drug users, and healthcare workers. Chronic HBV prevalence is highest in regions with perinatal transmission. HBV’s incubation is 45 to 160 days. Many cases are asymptomatic but symptoms can include fatigue, nausea, vomiting, jaundice, and abdominal pain. Lab findings show elevated aminotransferases and bilirubin. Acute HBV has approximately 1% case-fatality rate with fulminant hepatitis being rare. Chronic infection risk is inversely related to age at infection: >90% in neonates, 25%–50% in young children, and <5% in adults. Case Description/Methods: A 47-year-old man with no known history presented to the Emergency Department with body aches, lower extremity swelling, chills, headaches, and nausea. He had recent prior visits for purpura and edema; initial workups were negative for deep vein thrombosis, HIV, and hepatitis C. He was treated empirically for presumed cellulitis. On return, labs showed markedly elevated aspartate aminotransferase (AST) 1,902, alanine aminotransferase (ALT) 1,791, alkaline phosphatase (235), total bilirubin (3.3), and international normalized ratio (1.6). Urine drug screen was positive for cocaine. Hepatitis B serologies confirmed acute infection: positive surface antigen, core IgM antibody, and Be antigen; HBV DNA of 2.3 million IU/mL. Hepatitis A and C were negative. Imaging was unremarkable. Peak AST/ALT were 2545/2430, which trended down with supportive care. The patient admitted nasal cocaine use and unprotected sex with women; vaccination history was unknown. Discussion: This case reflects acute HBV with nonspecific symptoms and extrahepatic signs (purpura, edema), complicating early diagnosis. Serologies confirmed active infection. Elevated FIB-4 was likely confounded by acute injury. Given clinical improvement, the patient chose observation over immediate antivirals, aligning with guidelines recommending therapy only for severe or prolonged cases. He received counseling on partner notification, safe sex, and vaccination for contacts. Hepatology follow-up was arranged to monitor labs and assess for progression. This case highlights the importance of considering HBV in transaminitis and systemic symptoms, as well as the value of patient education and follow-up in managing acute infection.