What Is Uncommon Can Be Critical: A Case of Quinolone-Induced Acute Liver Failure

Many drugs are known to potentially cause liver injury; however, only a few reports investigate the association between levofloxacin and acute liver failure (ALF).  The case describes a 65-year-old man who was admitted with primary diagnoses of cerebrovascular accident (CVA) and acute coronary syndrome (ACS) who developed an upper respiratory tract infection for which he was started on levofloxacin. Following its administration, serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) increased more than 100-fold above the upper limit of normal. Over the next 24 hours, AST peaked at 9334 U/L, ALT at 4525 U/L, prothrombin time to 24.6 seconds, international normalized ratio (INR) to 2.22, and serum ammonia to 157 µmol/L. The patient developed signs and symptoms of decompensated liver disease, namely hepatic encephalopathy (HE). Levofloxacin was discontinued immediately, and evidence-based treatment per society guidelines from The American Association for the Study of Liver Diseases consisting of IV n-acetylcysteine as well as lactulose and rifaximin was initiated. Such medical management resulted in clinical resolution of his ALF, but he had a poor overall prognosis and eventually succumbed to critical illness.