S5441 Shroom or Doom: A Case of Ganoderma lucidum-Induced Liver Injury

Introduction: Ganoderma lucidum, commonly known as reishi mushroom, has been used in East Asia for centuries as a “herb of spiritual potency.” Reishi is widely available as powders, dietary supplements, and tea. Commonly believed benefits of reishi mushrooms include blood glucose regulation and modulation of immune systems. While generally considered safe, there have been reports of hepatotoxicity. We present a rare case of herbal supplement-induced liver injury (HILI) with reishi mushroom consumption. Case Description/Methods: A 57-year-old woman presented with a 5-day history of jaundice and worsening fatigue. She denied abdominal pain, recent travel, new food exposures, or blood transfusion. She reported taking multiple supplements including powdered reishi mushrooms, green tea extract, turmeric, ginkgo biloba, and vitamin D3. On admission, the patient was noted to have elevated liver function tests (LFTs) with aspartate aminotransferase (AST) 1,046 U/L, ALT 1,061 U/L, alkaline phosphatase 167 U/L, and total bilirubin of 12.3 mg/dL. Right upper quadrant ultrasound did not note any steatotic features or biliary duct dilation. Computed tomography (CT) abdomen and pelvis was also unrevealing. Comprehensive hepatic evaluation included autoimmune, viral hepatitis, and infectious serologies. Epstein-Barr virus and cytomegalovirus were ruled out and acute hepatitis panel was negative. Antinuclear antibody, smooth muscle antibody, and anti-mitochondrial antibody were also within normal limits. Given low suspicion for obstructive process, magnetic resonance cholangiopancreatography was not pursued. The patient was observed without intervention. By discharge, LFTs decreased to AST 896 U/L, ALT 950 U/L, and total bilirubin of 11.5 mg/dL. She was advised to discontinue all supplements and follow up closely with gastroenterology. LFTs were repeated a few months later with marked improvement including ALT 128 U/L, AST 106 U/L, and total bilirubin 0.80 mg/dL. Discussion: G. lucidum has been used for centuries and has been promoted for treatment of cancer, liver, and cardiovascular health. The benefits are attributed to its antioxidant and anti-inflammatory properties from major polysaccharides. However, several case reports have reported fatal fulminant hepatitis associated with reishi mushrooms. In our case, an extensive workup ruled out autoimmune and infectious etiologies, leaving G. lucidum as the most likely cause of acute liver injury. This case highlights the importance of recognizing potential hepatotoxic effects of commonly used herbal supplements like reishi mushrooms.