Specificity of, and influence of hemolysis, lipemia, and icterus on serum lipase activity as measured by the v-LIP-P slide.

BACKGROUND

Measurement of pancreatic lipase in serum is being used for the diagnosis of pancreatitis.

OBJECTIVES

The aims of this study were to measure serum lipase activity by the v-LIP-P slide and serum canine pancreatic lipase immunoreactivity (cPLI) concentration by Spec cPL in dogs with exocrine pancreatic insufficiency (EPI) and in serum samples that were hemolyzed, lipemic, or icteric.

METHODS

Serum samples from 50 dogs with EPI, 8 samples spiked with canine hemoglobin, Intralipid, or ditaurobilirubin, and 8 samples from dogs with severe hypertriglyceridemia were evaluated using v-LIP-P and Spec cPL assays.

RESULTS

Serum lipase activity (v-LIP-P) was in the lower 20% of the RI in 58% of EPI dogs, while serum cPLI (as measured by Spec cPL) was in the lower 20% of the RI in 98% of EPI dogs. The mean (±SD) observed-to-expected ratios for serum samples spiked with canine hemoglobin, Intralipid, or ditaurobilirubin were 63.0 ± 25.1%, 489.2 ± 469.7%, and 80.2 ± 11.6% for the v-LIP-P slide, respectively, and 99.3 ± 6.8%, 96.9 ± 9.4%, and 98.7 ± 11.0% for Spec cPL, respectively. However, naturally occurring hypertriglyceridemia did not appear to have a significant effect on serum lipase activity as measured by the v-LIP-P slide.

CONCLUSIONS

These results show that Spec cPL is specific for pancreatic lipase, while the v-LIP-P slide is not. In addition, hemolysis and lipemia had no effect on Spec cPL, while severe icterus resulted in a slight decrease in Spec cPL. Hemolysis and icterus had a significant effect on the v-LIP-P slide. The effect of lipemia on the v-LIP-P slide cannot be conclusively established based on this study.