Cardiac troponin I in patients receiving renal replacement therapy.
Current markers of myocardial injury lack specificity in patients with end-stage renal disease (ESRD). In particular, a false positive creatine kinase-MB (CKMB) elevation occurs in 5-10% of patients with ESRD. The aim of this study was to ascertain the relationship between CKMB and cardiac troponin I (cTnI), a new, highly sensitive and specific marker for myocardial injury, in the authors' dialysis population and compare their specificities. Blood samples were obtained from 112 dialysis patients (35 in peritoneal dialysis; 77 in hemodialysis). Patients were asymptomatic for cardiac ischemia and skeletal muscle injury. Mean +/- SD CKMB mass was 3.16 +/- 2.26 microg/L (range, 0.34-13.62), and cTnI was 0.025 +/- 0.061 ng/ml (range, 0.001-0.496). CKMB and cTnI levels did not correlate (r2 = 0.002; p = 0.61). CKMB mass concentration was significantly higher in men and in diabetics. No patient had a cTnI level greater than 1.5 microg/L, and eight asymptomatic patients had a CKMB mass greater than 6.7 microg/L. These data suggest a specificity of 100% for cTnI vs 94.6% for CKMB at these cutoff values. It is suggested that cTnI replace CKMB as a marker of myocardial injury in patients with ESRD.
Morton
A R
AR
Department of Medicine, Queen's University, Kingston, Ontario, Canada.
Collier
C P
CP
Ali
N
N
Dagnone
L E
LE
D003402:Creatine Kinase / Q000097:blood*; D005260:Female; D006801:Humans; D007527:Isoenzymes; D008297:Male; D008875:Middle Aged; D006435:Renal Dialysis; D012680:Sensitivity and Specificity; D019210:Troponin I / Q000097:blood*
D007527:Isoenzymes; D019210:Troponin I; D003402:Creatine Kinase