TY - JOUR
T1 - Individualized correction of neuron-specific enolase (NSE) measurement in hemolyzed serum samples
AU - Tolan, Nicole V.
AU - Vidal-Folch, Noemi
AU - Algeciras-Schimnich, Alicia
AU - Singh, Ravinder J.
AU - Grebe, Stefan K.G.
PY - 2013/9/23
Y1 - 2013/9/23
N2 - Background: Accuracy of serum neuron-specific enolase (NSE) measurement is paramount, particularly in the context of neurological outcome prognostication. However, NSE measurements are compromised by even slight hemolysis, as it is abundant in red blood cells (RBCs). We derived and validated an individualized hemolysis correction equation in an attempt to reduce the current rejection rate of 14% at our institution. Methods: Intracellular NSE was measured in RBC lysates to determine concentration variability. A correction equation was derived, accounting for both RBC-derived NSE false-elevation and hemoglobin-derived signal quenching. The performance of this individualized correction was evaluated in intentionally hemolyzed samples and accuracy was compared to a generalized correction. Results: Significant inter-individual variability of RBC NSE was observed, with an almost two-fold range (15.7-28.5ng NSE/mg Hb, p<0.001); intra-individual variability was insignificant. The individualized hemolysis correction equation derived: NSEcorr=NSEmeas-(Hbserum)(NSERBCs/Hb)+0.0844(Hbserum)+1.1 corrected 95% of the intentionally hemolyzed samples to within ±5ng/ml of corresponding baseline NSE concentrations, compared to 74% using a generalized formula. Conclusions: The individualized hemolysis correction provides increased accuracy in the estimation of true serum NSE concentrations for hemolyzed samples, compared to a generalized approach, by accounting for inter-individual RBC NSE variability. Incorporating this correction should reduce sample rejection rates and overall health care costs.
AB - Background: Accuracy of serum neuron-specific enolase (NSE) measurement is paramount, particularly in the context of neurological outcome prognostication. However, NSE measurements are compromised by even slight hemolysis, as it is abundant in red blood cells (RBCs). We derived and validated an individualized hemolysis correction equation in an attempt to reduce the current rejection rate of 14% at our institution. Methods: Intracellular NSE was measured in RBC lysates to determine concentration variability. A correction equation was derived, accounting for both RBC-derived NSE false-elevation and hemoglobin-derived signal quenching. The performance of this individualized correction was evaluated in intentionally hemolyzed samples and accuracy was compared to a generalized correction. Results: Significant inter-individual variability of RBC NSE was observed, with an almost two-fold range (15.7-28.5ng NSE/mg Hb, p<0.001); intra-individual variability was insignificant. The individualized hemolysis correction equation derived: NSEcorr=NSEmeas-(Hbserum)(NSERBCs/Hb)+0.0844(Hbserum)+1.1 corrected 95% of the intentionally hemolyzed samples to within ±5ng/ml of corresponding baseline NSE concentrations, compared to 74% using a generalized formula. Conclusions: The individualized hemolysis correction provides increased accuracy in the estimation of true serum NSE concentrations for hemolyzed samples, compared to a generalized approach, by accounting for inter-individual RBC NSE variability. Incorporating this correction should reduce sample rejection rates and overall health care costs.
KW - Individualized hemolysis correction
KW - Ischemic brain injury
KW - Neurological prognosis
KW - Neuron-specific enolase
KW - Therapeutic hypothermia
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U2 - 10.1016/j.cca.2013.06.009
DO - 10.1016/j.cca.2013.06.009
M3 - Article
C2 - 23778024
AN - SCOPUS:84880374237
SN - 0009-8981
VL - 424
SP - 216
EP - 221
JO - Clinica Chimica Acta
JF - Clinica Chimica Acta
ER -