Troponin I: how high is too high?

Area of Science:

• Cardiology
• Pediatric Critical Care
• Biochemistry

Background:

• Elevated cardiac troponin I (cTnI) is a common biomarker for myocardial injury.
• Sepsis can also lead to elevated cTnI, often attributed to myocardial depression or microvascular dysfunction.
• Extreme elevations of cTnI in pediatric patients without overt cardiac injury are uncommon.

Observation:

• A 14-year-old female sustained muscle injury from a motor vehicle accident.
• She was subsequently readmitted with sepsis.
• During sepsis, she presented with severely elevated serum cardiac troponin I levels.

Findings:

• Despite extremely high cardiac troponin I levels, diagnostic workup revealed no evidence of myocardial infarction or significant cardiac injury.
• The elevated cTnI was considered secondary to severe sepsis and possibly rhabdomyolysis from the initial trauma.
• This case demonstrates a dissociation between troponin levels and actual myocardial damage in a pediatric sepsis patient.

Implications:

• Clinicians should consider non-cardiac causes for markedly elevated cTnI in pediatric sepsis, especially in the presence of trauma or muscle injury.
• Over-reliance on cTnI alone may lead to misdiagnosis of myocardial injury in critically ill children.
• Further research is needed to understand the mechanisms of troponin release in sepsis-associated non-cardiac conditions.