Paracetamol-induced hepatotoxicity in a patient with alcohol dependence

A 48-year-old man presented to the emergency department with a two-day history of nausea, vomiting, right upper quadrant pain, and jaundice. He reported feeling generally unwell and noted dark urine. He had no other complaints.

Medication history: The patient had been taking paracetamol 1 g four times a day (4 g daily) for the past week for a knee injury. He had also been on atorvastatin 20 mg daily and amlodipine 5 mg daily for several years for hyperlipidemia and hypertension, respectively. He reported no other medications or over-the-counter products. He had not changed his regular medications.

Past medical history: He had a history of alcohol dependence, drinking approximately 10 units of alcohol per day, with poor dietary intake. There was no known history of liver disease, viral hepatitis, or recent exposure to hepatotoxic agents.

On examination: He was jaundiced, afebrile, with right upper quadrant tenderness on palpation. There were no stigmata of chronic liver disease, no ascites, no peripheral edema, and no asterixis. Cardiovascular and respiratory examinations were unremarkable.

Investigations: Initial liver function tests showed ALT 1800 U/L, AST 1200 U/L, ALP 220 U/L, total bilirubin 120 µmol/L, direct bilirubin 80 µmol/L, and INR 1.2. Serum creatinine was normal. Hepatitis A, B, C, and E serologies were negative. Antinuclear antibody was negative. Abdominal ultrasound showed a diffusely echogenic liver consistent with fatty change, with no biliary obstruction.

Hospital course: Paracetamol was discontinued on admission. Over the next five days, the patient's symptoms improved, and liver enzymes showed a downward trend: ALT decreased to 900 U/L and bilirubin to 80 µmol/L. The patient was discharged with monitoring. No rechallenge with paracetamol was performed.