The Forms and the Levels of Fecal PMN-elastase in Patients with Colorectal Diseases

Objectives: To compare the form of polymorphonuclear leukocyte (PMN)-elastase in feces with that in plasma and to investigate the usefulness of measuring fecal PMN-elastase levels in patients with colorectal diseases.

Methods: We examined PMN-elastase complexed with alpha 1-antitrypsin (alpha 1-AT), chymotrypsin, and alpha 2-macroglobulin by ELISA in feces and plasma. Fecal levels of total PMN-elastase were determined in patients with colonic polyp (N = 19), colonic cancer (N = 20), ulcerative colitis (UC; N = 36), colonic Crohn's disease (CD; N = 26), and in control subjects (N = 20).

Results: Most PMN-elastase was not complexed with alpha 1-AT, chymotrypsin, or alpha 2-macroglobulin in feces, whereas most plasma PMN-elastase was complexed with alpha 1-AT. Fecal concentrations and daily fecal excretion of PMN-elastase were significantly increased in patients with active UC (medians 54.8 micrograms/g, 15.14 mg/day) and active CD (41.5 micrograms/g, 10.24 mg/day) compared to those values in control subjects (0.6 micrograms/g, 0.11 mg/day) and in patients with colonic cancer (2.5 micrograms/g, 0.33 mg/day). In inactive UC and CD, these values (3.4 micrograms/g, 0.52 mg/day and 5.2 micrograms/g, 0.59 mg/day, respectively) were significantly lower than in active UC and CD, respectively. In UC, all patients whose rectal biopsies showed infiltration of PMN had high fecal PMN-elastase levels.

Conclusions: Our results suggest that the measurement of fecal PMN-elastase concentrations are useful for monitoring the disease activity of UC and CD, especially when evaluating whether intestinal inflammation has disappeared completely.