Assessment of a rapid pancreatic isoamylase assay as a screening test for chronic pancreatic disease.

A new, rapid assay for pancreatic isoamylase (PIA) has been evaluated in normal subjects and patients with either proven chronic pancreatic disease or diseases in which chronic pancreatitis commonly enters the differential diagnosis. A wide normal range limited the diagnostic usefulness of the test. In non-pancreatic disease the serum levels of PIA were normal in 107 of 109 patients with non-pancreatic disease, but only 3 of 16 patients with chronic pancreatitis and proven exocrine insufficiency had a low PIA level, and variable levels occurred in pancreatic carcinoma. These results suggest that measurement of serum PIA is of limited value as a screening test for chronic pancreatic disease.