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Title: Can transaminase and CK ratio help differentiate rhabdomyolysis vs. delayed acetaminophen overdose?

Category: Toxicology

Keywords: transaminitis, delayed acetaminophen toxicity, rhabdomyolysis (PubMed Search)

Posted: 7/26/2018 by Hong Kim, MD (Updated: 3/3/2026)

Elevated transaminases are found in both rhabdomyolysis and delayed acetaminophen (APAP) toxicity. Establishing the cause of elevated transaminase can be difficult when there is unclear history of acetaminophen ingestion.

A retrospective study of patients with delayed acetaminophen toxicity or rhabdomyolysis from 2006 to 2011 was recently published.

The authors compared AST/ALT, CK/AST and CK/ALT ratio of 

  • 160 in the rhabdomyolysis group
  • 68 in the acetaminophen overdose (all)
  • 29 in the delayed acetaminophen overdose group

Results

AST/ALT ratio

  • Rhabdomyolysis group: 1.66
  • APAP overdose (all): 1.38
  • Delayed APAP overdose: 1.3

CK/AST ratio

  • Rhabdomyolysis group: 21.3
  • APAP overdose (all): 5.49
  • Delayed APAP overdose: 3.8

CK/ALT ratio

  • Rhabdomyolysis group: 37.1
  • APAP overdose (all): 5.77
  • Delayed APAP overdose: 5.03

Conclusion

  • Significantly higher ratio of AST/ALT, CK/AST and CK/ALT were found in rhabdomyolysis patients than delayed APAP overdose patients.
  • These finding are based on small study population and need further validation/research before clinical application.