Evaluation of an automated colorimetric assay for the measurement of lipase activity in canine sera.

An automated colorimetric method for determining lipase activity in canine sera was evaluated for precision, linearity and correlation to existing assay methods. The colorimetric method was a commercial reagent that used a series of enzymatic reactions based on the hydrolysis of 1,2 diglyceride by pancreatic lipase. Within-run and between-run coefficients of variation were < 6.8% and < 8.3%, respectively. Linearity was determined to be at least 1366 U/L. Canine serum lipase concentrations attained using the colorimetric method were compared to both titrimetric and dry-film methods for measuring serum lipase activity, resulting in significant (P < or = 0.05) correlation coefficients of 0.92 and 0.77, respectively. Canine serum lipase concentrations measured using the colorimetric assay on 2 different automated analyzers had a significant (P < or = 0.05) correlation coefficient of 0.92. A laboratory reference range using serum samples from 56 healthy dogs (0-561 U/L) was established. There were no significant (P < or = 0.05) differences in mean serum lipase concentrations comparing male and female dogs or comparing young dogs (< or = 3 y) to mature (4-7 y) and older (> 7 y) dogs using this assay. It was concluded that the automated colorimetric assay was a reliable indicator of canine serum lipase activity and offered several advantages, including small sample volume and short analysis time.