Purpose:Purpose: Vanishing Bile Duct Syndrome (VBDS) is an acquired disorder of cholestasis characterized by the destruction and ultimate disappearance of the intrahepatic bile ducts. The presentation of VBDS is highly variable due to its numerous underlying causes. Outcomes range from favorable with gradual regeneration and recovery to devastating with progressive and irreversible bile duct loss. We describe a case of an elderly male with jaundice following moxifloxacin exposure found to have VBDS on liver biopsy. Despite drug discontinuation cholestatic hepatitis persists. Case: An 82 year-old male with no significant past medical history was admitted to the hospital with empyema that was treated with intravenous antibiotics and drainage. On hospital day 21, he was discharged on a continuing course of oral moxifloxacin 400 mg daily. Eight days later he presented with jaundice and mild pruritis. He denied fevers, nausea, vomiting, abdominal pain, or change in stools. The exam was notable for marked jaundice and a palpable liver edge 3 cm below the costal margin. Laboratories revealed an alkaline phosphatase of 821 IU/L, ALT of 441 IU/L, total bilirubin of 15.3 mg/dl, and direct bilirubin of 9.2 mg/dl. Viral hepatitis and autoimmune serologies, iron studies, abdominal CT scan, right upper quadrant ultrasound with dopplers, MRCP, and ERCP produced inconclusive results. A liver biopsy was performed revealing cholestatic hepatitis with bile stasis and marked ductopenia. He was started on ursodiol (15 mg/kg) and cholestyramine (4 mg). At 3 months follow-up, the patient reported improved pruritis however liver chemistries remained markedly elevated with an alkaline phosphatase of 226 IU/L, ALT of 128 IU/L, total bilirubin of 25.8 mg/dl, and direct bilirubin of 14.5 mg/dl. Discussion: Cholestasis due to drug toxicity accounts for 2–5% of admissions for jaundice and up to 20% of cases of jaundice in the geriatric population. Moxifloxacin is a known hepatotoxin producing symptoms 3–10 days after drug ingestion and has been reported to cause fulminant hepatic failure and death. VBDS in association with flouroquinolone use is exceedingly rare with only one case reported in the literature. Most cases of VBDS resolve within 6 months, however VBDS can persist and lead to secondary biliary cirrhosis, liver failure, and death. The proposed mechanism of bile duct loss is T-cell toxicity and a dysregulation of apoptosis. Treatment requires recognition and prompt discontinuation of the inciting agent, although this does not uniformly lead to improvement. Corticosteroids, rifampicin, and opiate antagonists have been used for symptom management, however evidence regarding their efficacy is limited.