Inhibitor test for amylase isoenzymes: comparison with a simplified chromatographic method.

The percentage of pancreatic-type isoamylase activity and the ratio of pancreatic to salivary-type isoamylase activity were determined in five control and 35 hyperamylasemic serum samples by means of an established simplified chromatographic method and a recently described inhibitor test. There was good correlation in the results, except at very high and at very low levels of P-type isoamylase activity. At these extremes, the inhibitor method yields imprecise quantitative results. The inhibitor test findings may also prompt misleading conclusions when elevated serum amylase activity is due to undetected macroamylasemia.