Cardiac troponins in patients with renal dysfunction

Cardiac troponin T (cTnT) and cardiac troponin I (cTnI) were measured in 198 patients with renal dysfunction [132 men: median (range) age 66.1 (8.2-90.3) years], cTnT was measured by two methods: ELISA and Enzymun (Boehringer Mannheim UK, Lewes, UK), both with a detection limit of 0.05 mu g/L in 179 and 78 patients, respectively. cTnI was measured in 80 patients by the OPUS plus and OPUS Magnum systems (Dade-Behring, Milton Keynes, UK) with a detection limit of 0.5 mu g/L. Patients were classified as having chronic renal impairment (CRI), chronic renal failure (CRF), acute renal failure including those with multiple organ failure on renal replacement therapy (ARF), and patients with chronic renal failure treated with haemodialysis (HD). Cardiac troponins were detectable in the serum of patients with renal dysfunction. cTnT was detectable in 113/179 (63.1%) and 33/78 (42.3%) by the ELISA and Enzymun methods respectively. cTnI was detectable in 17/80 (21.3%). cTnT (ELISA and Enzymun methods) and cTnI were detectable with increased frequency in the CRF, HD and ARF patient groups compared with the CRI group. Cardiac troponin concentrations did not correlate with serum creatine kinase (CK) activity, CK-MB, or urea or creatinine levels. Serial cardiac troponin measurements may be required to confirm or exclude a diagnosis of acute coronary syndromes in patients with renal dysfunction.