A Rare Cause of Fulminant Liver Failure: Diagnosing HSV Hepatitis in a Patient with Tylenol Toxicity

Abstract

Introduction: Herpes simplex virus (HSV) hepatitis is a rare cause of acute liver failure (ALF) with a high mortality rate. Clinical presentation is often non-specific and diagnosis is based on HSV PCR with liver biopsy serving as gold standard. We report a case of ALF in the setting of tylenol use confounding an underlying diagnosis of HSV hepatitis. Case: A 55-year-old female with past medical history of hypertension and immune thrombocytopenic purpura, on prednisone, presented to an OSH ER after receiving an outpatient platelet transfusion with chief complaint of fever. Over the next 24 hours she was given 7 grams tylenol along with platelet transfusions. Labs were notable for AST/ALT 1331/1920, TB 2.8, INR 0.8, and tylenol level < 3. NAC therapy was initiated yet liver enzymes continued to trend up with AST/ALT 12,700/7,627, TB 6.8, and INR 1.5. She was then transferred to Georgetown University hospital for transplant evaluation. On admission, she was febrile with physical exam notable for scleral icterus, RUQ tenderness, hepatomegaly, without mucocutaneous or genital lesions. Significant labs include: Na 123, plt 44, TB 7.9, DB 6.4, AST 7539, ALT 8359, AKP 349 and INR 1.8. Liver tests continued to rise, despite NAC therapy with progression to encephalopathy, and oliguria requiring CRRT. Hepatitis work-up was significant for HSV-1 PCR >2,000,000 copies and IV acyclovir was initiated. She underwent a transjugular liver biopsy with H&E stain that revealed multiacinar (zone 1) hepatic necrosis consistent with tylenol toxicity (fig 1). Immunochemical stain with necrotic foci strongly positive for HSV (fig 2). Acyclovir dose was increased to 600 mg IV daily. Her mental status improved significantly on therapy. On discharge, liver tests returned to normal, with improvement of renal function, no longer requiring dialysis.Figure 1Figure 2Discussion: HSV is a rare but fatal cause of fulminant liver failure that is often missed due to vague symptoms and lack of mucocutaneous or genital lesions on presentation. In this case, diagnosis of HSV was especially difficult in the setting of tylenol toxicity. However, with a high index of suspicion in an immunosuppressed patient, she was diagnosed and treated in a timely manner which led to complete resolution of ALF.