Comparison of amylase and lipase activities in serum and plasma of dogs.

Abstract

BACKGROUND: Amylase and lipase activities are most often determined in serum, although heparinized plasma is more convenient to obtain and is used for many routine biochemical analyses. OBJECTIVE: The purpose of this study was to compare amylase and lipase activities in serum and plasma of dogs and to determine whether either specimen type is acceptable for analysis. METHODS: Serum and heparinized plasma were obtained from 101 randomly selected dogs and analyzed in parallel for alpha-amylase and lipase. Results were compared using Passing-Bablock regression, Bland-Altman difference plots, and correlation analysis. RESULTS: There was a high correlation between the results obtained from serum and those from plasma. Regressions (with 95% confidence intervals in parentheses) were as follows: lipase(plasma) = 0.984 (0.976/0.995) Chi lipase(serum) - 0.9 (2.9/0.7) (r =.999); a-amylase(plasma) = 1.003 (0.977/1.032) Chi alpha-amylase(serum) - 1.9 ( 20.7/23.3) (r =.991). Mean differences (serum - plasma) were 8 U/L and 4 U/L for lipase and alpha-amylase, respectively. Classification of results as normal or abnormal did not differ according to specimen type. CONCLUSION: In dogs, lipase and alpha-amylase activities can be determined with the same level of accuracy in serum and in heparinized plasma.