A Case of Acetaminophen Toxicity in a Patient With an Unusual Alpha-1 Antitrypsin Phenotype.

Acetaminophen is a commonly used over-the-counter analgesic and antipyretic that can be hepatotoxic if taken in excess. We present a case of acetaminophen-mediated hepatotoxicity following ingestion of a non-toxic dose of acetaminophen in a 16-year-old male with short bowel syndrome and a remote history of severe liver dysfunction with a rare alpha-1 antitrypsin phenotype Pi*EM. The patient initially presented with nonspecific symptoms of abdominal pain, nausea, vomiting, and diarrhea. N-acetylcysteine (NAC) therapy was initiated for acetaminophen toxicity. We suspect that the patient's susceptibility to acetaminophen-induced liver injury was likely due to underlying intestinal failure-associated liver disease that occurred as a child, as well as the Pi*EM, making the liver more prone to insults. This case highlights the importance of prompt recognition and management of acetaminophen toxicity in patients with prior liver disease, even if the amount ingested is thought to be non-toxic. In addition, the case highlights that rare alpha-1 antitrypsin phenotypes should be treated with heightened caution for liver dysfunction, as there is limited literature indicating if these phenotypes are pathogenic or non-pathogenic.