Introduction: Respiratory syncytial virus (RSV) predominantly affects children and typically manifests as an upper respiratory tract infection. Primary RSV infection in immunosuppressed adults may increase risks of disseminated infection manifesting as RSV hepatitis. RSV hepatitis may present with fever, abdominal pain, nausea, vomiting, jaundice, coagulopathy, and elevation of transaminases. Case Description/Methods: A 29-year-old woman with 10 weeks of pregnancy, history of anemia and vitamin B12 deficiency was admitted to the hospital for fatigue, intractable nausea, vomiting and inability to tolerate oral intake. She denied respiratory symptoms. She was taking prenatal multivitamins but denied starting new medications or supplements. At presentation, her vital signs and clinical exam were unremarkable with uterine fundus palpable just above the pubic bone. Initial laboratory work up revealed elevated liver enzymes with AST 497 U/L, ALT 712 U/L, normal total bilirubin and ALP. Abdominal ultrasound (US) demonstrated cholelithiasis without evidence of cholecystitis or common bile duct dilation. Subsequent workup including an acute hepatitis panel; CMV, EBV serology; stool H. pylori testing; and autoimmune workup was negative. HSV IgM serology was indeterminant. A respiratory viral molecular panel by PCR was positive for RSV. Abdominal US with doppler showed normal hepatic and portal vessel blood flow and magnetic resonance cholangiopancreatography was negative for choledocholithiasis. She was treated supportively with intravenous fluids, antiemetics and close fetal monitoring. Her liver enzymes peaked on hospital day 4 with AST 863 U/L, ALT 1214 U/L, total bilirubin 1.1 mg/dL. By hospital day 5, her symptoms improved, and she was discharged. At 5 week follow up, AST and ALT improved to 62 U/L and 82 U/L, respectively. Her elective laparoscopic cholecystectomy was deferred until after delivery due to symptom resolution and absence of acute cholecystitis. Discussion: Disseminated RSV a rare manifestation in immunocompromised individuals. Clinical presentation may be atypical, creating diagnostic challenges. Liver biopsy is rarely required to establish the diagnosis. RSV hepatitis is typically self-limited and can be treated with supportive care as antiviral agents have no proven efficacy. A high index of suspicion is required for early identification of RSV hepatitis as timely supportive care may prevent progression to acute liver failure. Table 1. - Laboratory Testing Done to Investigate Emesis Etiology Caption Laboratory Test Reference Range and Units Results Liver Function Tests Alanine aminotransferase (ALT) 0-34 U/L 990 (H) Aspartate aminotransferase (AST) 15-46 U/L 750 (H) Alkaline phosphatase (ALP) 38-126 U/L 89 (N) Total bilirubin 0.2-1.3 mg/dL 1.4 (H) Total Protein 6.3-8.2 g/dL 6.4 (N) Albumin 3.5-5.0 g/dL 3.6 (N) Coagulation Studies Prothrombin time (PT) 9.0-12.0 10.9 (N) International normalized ratio (INR) 0.9-1.1 1.0 (N) Viral Serologies Hepatitis A, IgM Non-reactive Non-reactive Hepatitis B, core IgM Non-reactive Non-reactive Hepatitis B, surface antigen Non-reactive Non-reactive Hepatitis C antibody Non-reactive Non-reactive Hepatitis E antibody Non-reactive Non-reactive Human immunodeficiency virus 1 and 2 antibody/antigen Non-reactive Non-reactive Herpes simplex virus 1 and 2 IgM < =0.89 0.96 (intermediate) Cytomegalovirus quantitative PCR Non-reactive Not detected Epstein Barr virus, IgM Not detected Not detected Influenza A, antigen Not detected Not detected Influenza B, antigen Not detected Not detected Respiratory Syncytial Virus Not detected Detected Autoimmune liver disease panel Liver-Kidney Microsome-1 Antibody IgG (Anti-LMK) 0.0 - 24.9 U 0.8 (N) Antinuclear antibody (ANA) titer < 1:80 < 1:80 (N) Anti-smooth muscle antibody (ASMA) 0-19 Units 6 (N) Antimitochondrial antibody (AMA) 0.0-24.9 Units 2.4 (N) Miscellaneous Rapid plasma regain (RPR) Negative Negative Total Creatinine Kinase (CK) 30-170 U/L < 20 (L) H. pylori antigen Negative Negative - H: High; N: Normal; L: Low.