2228 A Rare Report of Pantoprazole-Induced Acute Hepatocellular and Cholestatic Hepatitis

Abstract

INTRODUCTION: Pantoprazole is a widely used proton pump inhibitor that is used to treat variety of acid related disorders. It is well tolerated with excellent safety profile. Mild transient elevations in serum aminotransferase can be seen with pantoprazole use that resolves without dose modification. Pantoprazole induced clinically apparent liver injury on the other hand is exceedingly rare. CASE DESCRIPTION/METHODS: A 47-year-old woman with no prior liver disease was referred to the hospital for acute hepatitis. She started pantoprazole 2 months prior to admission for gastritis. Patient had nausea, fatigue, abdominal pain, jaundice and dark urine 2 weeks after starting pantoprazole and stopped it a week prior to hospital admission. She denied alcohol use. Her current medications were levothyroxine, enalapril/hydrochlorothiazide and aspirin and no use of herbal supplements. Physical exam was notable for conjunctival icterus. Baseline liver enzymes were normal. Labs on admission were: AST 681 U/L (< 32 U/L), ALT 2100 U/L (< 36 U/L), total bilirubin 12.3 mg/dL (0.2-1.2 mg/dL), direct bilirubin 8.3 mg/dL (< 0.5 mg/dL), alkaline phosphatase 96 U/L (45-117 U/L) and INR 1.9 (0.8-1.2). Urine drug screen was negative for acetaminophen toxicity. Imaging excluded biliary obstruction and hepatic venous thrombosis. Laboratory investigations for viral and autoimmune hepatitis, wilson’s disease and hemochromatosis were negative. Liver biopsy (Figure 1) reported portal areas with edema and a minimal amount of inflammation composed of mixed lymphocytes, occasional eosinophils and neutrophils. The lobular parenchyma showed cholestasis with lymphocytic and neutrophilic inflammation. Patient noted improvement of symptoms with supportive care (Table 1). Two months after stopping pantoprazole, liver enzymes were normal. DISCUSSION: DILI (drug-induced liver injury) is a significant cause of acute hepatitis. To our knowledge, only 7 case reports of pantoprazole induced liver injury have been published. The timing of starting pantoprazole prior to acute hepatitis, negative serologies, and normalized liver enzymes after stopping suggests pantoprazole as the cause of DILI. Based on its pharmacokinetics, timeline and pattern of insult, an idiosyncratic reaction has been suggested as the mechanism for hepatotoxicity. We have described a rare case of acute mixed (hepatocellular and cholestatic) liver injury from pantoprazole use suggesting its consideration in the differential diagnosis of DILI.