Elevated Troponin Essay

The interpretation of elevated troponin in the presence of kidney disease.
Everyday in emergency departments across the county troponins are routinely being utilized as part of the workup for patients with chest pain. The reason for this is that troponins indicate damage to myocardium and elevated levels suggest myocardial cell injury. Elevated troponins in a patient presenting with acute coronary syndrome may be an indication for early interventional therapies, however it has long been noted that troponins may be elevated in certain non-cardiac conditions as well. The most common of these conditions is pulmonary embolism, sepsis and renal insufficiency. (4) In patients with end stage renal disease (ESRD), elevated troponins are present without any signs or

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Patients with end-stage renal disease (ESRD) have long been noted to have elevated troponins in the absence of acute myocardial ischemia (MI).
Some studies quote as high as 70% of patients with kidney disease have elevated troponins without an acute MI. (1) The source of this elevation in patients with ESRD remains unclear though several studies have proposed various causes for this increase. Second generation antibody assays evaluate
TnI rather than TnT as it was found that the first generation assays had crossreactivity with skeletal muscle TnT. ( 2) Studies using the first generation assays found that in ESRD patients who were not having an acute MI, 71% of patients had elevation in TnT while only 7% of these patients had elevation in TnI. (2)
There have been many hypotheses to the cause of this elevation, some state that uremia causes expression of TnT from injured skeletal muscle fibers. It has been found that there are several isoforms of TnT some of which are found in skeletal muscles and the first generations assays did not have the ability to distinguish between these isoforms. (2) Though Song et al. refuted this