Can rhabdomyolysis cause an elevated troponin-T (troponin T) level?

Rhabdomyolysis Can Cause Elevated Troponin-T Levels

Yes, rhabdomyolysis can cause elevated troponin-T levels, with approximately 17% of patients with rhabdomyolysis showing false-positive troponin-T results despite no evidence of cardiac injury. 1

Mechanism and Specificity of Cardiac Biomarkers

Cardiac troponins (T and I) are considered highly specific markers for myocardial damage, as they are exclusively expressed in cardiac myocytes 2. However, important differences exist between troponin T and troponin I in certain clinical scenarios:

• Troponin T: While highly specific for cardiac injury, troponin T can show false-positive elevations in patients with rhabdomyolysis 1
• Troponin I: Generally maintains better specificity in rhabdomyolysis and renal disease 3, 4

Evidence of False-Positive Troponin-T in Rhabdomyolysis

Research has demonstrated that troponin-T can be falsely elevated in patients with rhabdomyolysis:

• A retrospective cohort study found that 17% of emergency department patients with rhabdomyolysis (defined as CK ≥1000 U/L) had false-positive troponin-T results 1
• These patients had elevated troponin-T but normal electrocardiograms and echocardiograms, indicating no actual cardiac injury 1
• There was poor correlation between peak CK and peak troponin-T levels (r = -0.08) 1

Clinical Significance and Mortality Risk

Despite being potentially false-positive from a cardiac injury perspective, elevated troponin-T in rhabdomyolysis carries prognostic significance:

• Recent research indicates that elevated troponin levels in rhabdomyolysis are associated with significantly higher 90-day mortality rates, even in patients with normal kidney and left ventricular function 5
• These patients often require longer hospital stays and have more comorbidities 5

Troponin-T vs. Troponin-I in Special Populations

The discordance between troponin T and troponin I is particularly notable in patients with renal disease:

• In one study of patients with renal disease, troponin-T was elevated above the reference limit in 25% of patients, while troponin-I was elevated in only one patient 4
• A case report described a patient with rhabdomyolysis and acute renal failure whose troponin-T reached 67.5-fold the upper reference limit despite no evidence of myocardial damage, while troponin-I remained normal 3

Recommendations for Clinical Practice

When evaluating troponin-T elevations in patients with rhabdomyolysis:

1. Consider the possibility of false-positive results: Approximately 17% of rhabdomyolysis patients may show elevated troponin-T without cardiac injury 1

2. Use troponin-I when available: Troponin-I appears to maintain better specificity in rhabdomyolysis and renal disease 3, 4

3. Perform additional cardiac evaluation: For patients with elevated troponin-T and rhabdomyolysis, obtain:

   • 12-lead ECG to evaluate for ischemic changes
   • Echocardiography to assess for regional wall motion abnormalities 6

4. Monitor closely: Even if deemed a false-positive, elevated troponin-T in rhabdomyolysis is associated with higher mortality and may warrant more intensive monitoring 5

Common Pitfalls to Avoid

• Don't assume all troponin elevations in rhabdomyolysis represent cardiac injury: False-positive troponin-T results occur in approximately 17% of cases 1

• Don't dismiss elevated troponin-T as clinically irrelevant: Even when not indicating cardiac injury, elevated troponin-T in rhabdomyolysis is associated with higher mortality 5

• Don't rely solely on CK levels: There is poor correlation between CK and troponin-T levels in rhabdomyolysis 1