To determine the usefulness of information provided by measurement of serum
amylase activity in the evaluation of dogs for
pancreatitis, the relationship of
amylase activity to
lipase activity in 713 paired serum samples was investigated by statistical analysis. Little change in mean
amylase concentration was found until
lipase values exceeded 800 U/L. The ranges of
amylase activity (mean +/- 2 SD) were essentially the same for dogs with no
pancreatitis (0 to 100 U of
lipase activity/L) as for dogs with a high probability for the disease (700 to 799 U of
lipase activity/L), 0 to 4,029 U/L and 857 to 4,869 U/L, respectively. Pathologic findings from biopsy and necropsy reports from 92 dogs for which serum
lipase determinations were done indicated that serum
lipase increased not only with
pancreatitis, but also with other medical problems, such as renal and hepatic disease. It was concluded that determination of serum
amylase activity without knowledge of serum
lipase activity was of little value to diagnose
pancreatitis. High
amylase activity was not specific for
pancreatitis and low
amylase activity could not rule out the disease. The results of this study also showed that low serum
lipase values almost always eliminated the possibility of
pancreatitis and that high values were often, but not always, diagnostic for
pancreatitis.