PMN-elastase is a proteinase released by activated neutrophils. PMN-el
astase was determined in two independent populations with inflammatory
bowel disease In an unselected population of 70 consecutive patients
with Crohn's disease and 24 patients with ulcerative colitis with diff
erent degrees of disease activity plasma PMN-elastase levels were stat
istically significantly higher in patients with active than in patient
s with inactive disease [Crohn's disease: 80.5 +/- 33.2 ng/ml vs 60.1
+/- 24.6 ng/ml (means +/- sD), P = 0.0017; ulcerative colitis: 98.2 +/
- 54.9 ng/ml vs 59.2 +/- 16 8 ng/ml, P = 0.026]. PMN-elastase levels i
n feces were also higher in patients with active Crohn's disease (23.6
+/- 15.3 ng/g vs 13.6 +/- 12.5 ng/g, P = 0.0021) and active ulcerativ
e colitis (46.5 +/- 60.5 ng/g vs 20.2 +/- 25.0 ng/g, P = 0.46), but th
e difference reached significance only in Crohn's disease. Correlation
of disease activity and PMN-elastase in individual patients showed a
statistically significant correlation between plasma and fecal elastas
e concentrations and disease activity in ulcerative colitis (plasma: r
= 0.72, P < 0.001; feces: r = 0.57, P = 0.002). In patients with Croh
n's disease only plasma levels of PMN-elastase (r = 0.423, P < 0.001)
but not fecal elastase concentrations (r = 0.0083, P = 0.485) correlat
ed significantly with disease activity. Plasma PMN-elastase correlated
weakly with fecal PMN-elastase levels in Crohn's disease (r = 0.431,
P < 0.01) and in ulcerative colitis (r = 0.515, P = 0.05). In 28 patie
nts with highly active Crohn's disease [median severity activity index
(SAI) 203] and 11 patients with highly active ulcerative colitis [med
ian Rachmilewitz index (RI) 14] studied before and four weeks after st
eroid therapy, treatment lowered the median SAI to 140 and the median
RI to 4.5. Mean plasma elastase concentrations decreased concomitantly
from 83 +/- 44.9 ng/ml to 61.8 +/- 25.8 (P = 0.0035) in patients with
Crohn's disease and from 110 +/- 49.5 to 71.6 +/- 28.8 ng/ml (P = 0.0
069) in patients with ulcerative colitis. In conclusion, there is a re
lease of PMN-elastase in active IBD, which can be detected in plasma a
s well as in feces. Plasma elastase levels reflect disease activity in
patients with IBD. The variation of the data and the large overlap be
tween different groups, however, strongly reduce the clinical value