Using an immunoenzymatic method, we studied
lipase in the serum and urine of 23 controls, 22
chronic pancreatitis patients in symptomatic remission, and in 9 patients with proven
pancreatic cancer. Serum and urine
lipase and its fractional urinary clearance were compared with those of
amylase and immunoreactive
trypsin.
Lipase immunoreactivity was detectable in the urine of 81.5% of the studied subjects (controls: 82%,
chronic pancreatitis: 86%,
pancreatic cancer: 66%); its output was higher than the upper limit of controls in 31.8% of
chronic pancreatitis and in only 1 of
pancreatic cancer, and it was significantly correlated with the urinary output of
trypsin (r = 0.487, P less than 0.001), but not with that of
amylase. A significant correlation was found between urinary output and serum levels for
lipase, but not for
trypsin or
amylase. Fractional clearance of
lipase was of the same magnitude as that of
trypsin but only 0.1% that of
amylase. 19% of
chronic pancreatitis and
pancreatic cancer showed a fractional clearance of
lipase above the upper limit of controls, compared with 45% for
trypsin and 3.2% for
amylase. No difference in urinary clearance of the three
enzymes was found between
chronic pancreatitis and
pancreatic cancer. In conclusion, although of no diagnostic relevance in
pain-free patients with chronic
pancreatic disease, this measurement can provide information on the mechanisms of renal excretion of pancreatic
enzymes.