IPLab:Lab 12:Acetaminophen Toxicity

Clinical Summary

This 77-year-old white male with a past medical history of severe osteo- and rheumatoid arthritis went to his internist for increasing joint pain and was started on a new medication containing a narcotic analgesic, acetaminophen, and a non-steroidal anti-inflammatory agent. The patient also self medicated with acetaminophen. Two days later he went back to his doctor complaining of nausea and vomiting, right upper quadrant pain, anorexia, and confusion. Lab evaluation revealed massively increased liver enzymes. The patient went into DIC and died in fulminant liver failure.

At autopsy the liver had large areas of pale softened tissue indicative of liver necrosis.

Images

Virtual Microscopy

Liver: Acetominophen Toxicity

<peir-vm>IPLab12Acetaminophen</peir-vm>

Normal Liver

<peir-vm>UAB-Histology-00149</peir-vm>

Study Questions

  • <spoiler text="What is the most likely cause for the liver necrosis seen in this patient?">The acetaminophen level on admission was not elevated; however, the patient had been in distress for some time and had not taken any acetaminophen within the previous 12 hours. Upon questioning, the patient admitted that he had continued to take his usual doses of acetaminophen even after his internist put him on new drugs. He was unaware that one of the new drugs he was taking had acetaminophen in it. Thus, he was taking an overdose of acetaminophen and this resulted in hepatic toxicity.

Adverse drug reactions can occur with therapeutic agents, but in this case the most probable cause for liver necrosis was the unintentional overdose of acetaminophen by this patient who was not aware that one of the new drugs he was taking already contained acetaminophen.</spoiler>

  • <spoiler text="Why did this patient develop DIC?">Liver necrosis releases thromboplastin and can initiate the coagulation cascade leading to intravascular coagulation.</spoiler>

Additional Resources

Reference

Journal Articles

Images

Related IPLab Cases