S5119 The Accidental Brewer: When the Gut Turns into a Brewery

Introduction: Auto-brewery syndrome (ABS) is a rare condition where gut microorganisms, such as Saccharomyces cerevisiae or Candida species, ferment dietary carbohydrates into ethanol, causing intoxication-like symptoms without alcohol consumption. ABS poses psychosocial and legal challenges, necessitating accurate diagnosis and management. Case Description/Methods: A 41-year-old man presented with metabolic dysfunction-associated steatotic liver disease (MASLD, confirmed by liver biopsy), recurrent falls, amnesia, slurred speech, halitosis, unintentional weight loss (BMI 18.9 kg/m²), and personality changes. He consumed ∼5 lbs of candy daily. His wife reported intoxication-like episodes despite alcohol abstinence. He had multiple prior hospitalizations. During a symptomatic admission, a 24-hour glucose challenge test was positive, with a serum ethanol level of 417.7 mg/dL. Phosphatidylethanol level was completed after a week of inpatient admission and was found to be 667. Esophagogastroduodenoscopy and colonoscopy were performed, which was unremarkable for overgrowth. His dentist reported bacterial fungal overgrowth. Patient had completed treatments with rifaximin 550 mg 3 times daily and fluconazole 200 mg daily. He underwent fecal microbiota transplant (FMT) twice and did well initially, but continues to experience relapses. He currently follows a high protein and low carbohydrate diet. Symptoms persist, indicating refractory ABS. Discussion: ABS treatment involves reducing ethanol production via low-carbohydrate diets, probiotics, and antimicrobials (e.g., rifaximin, fluconazole) for overgrowth. FMT, used for Clostridioides difficile, is emerging for ABS but lacks clinical trials. It may be considered in refractory cases or significant quality-of-life impairment, though contraindicated in severe immunosuppression. This case highlights ABS’s diagnostic and therapeutic challenges. ABS should be considered in patients with unexplained intoxication-like symptoms, especially with high-carbohydrate diets. Management requires dietary modification, antimicrobials, and potentially FMT. A NIH sponsored clinical trial is currently on-going for the latter and is actively recruiting patients.