LAUSR

Objectives Ethanol is a widely consumed drug in almost every society. In this study, the potential interfering effect of ethanol on routine biochemical tests was evaluated. Methods Serum pools were prepared from blood samples collected from patients seeking treatment at the emergency department. Five separate groups were formed by adding ethanol to the samples, so the final concentrations were negative: 50 mg/dL, 100 mg/dL, 200 mg/dL, and 400 mg/dL. Each group was divided into 20 portions, and routine biochemical tests were measured from each portion. The coefficient of variation (CV), bias, and total error values were calculated for the measured parameters. Results Alanine aminotransferase (ALT; EC 2.6.1.2) and lactate dehydrogenase (LDH; EC 1.1.1.27) activities decreased in proportion to the ethanol level. High negative biases were observed, suggesting a dose-dependent negative interference. The total error values calculated for direct bilirubin and urea were higher than the allowable total error reported in the Clinical Laboratory Improvement Amendments of 1988. For direct bilirubin, it was observed that the cause of this shift was due to the increase in CV values. Conclusions We conclude that ethanol may cause interference in the measurement of some biochemical tests, whereas the most prominent effect was observed for LDH and ALT.