Activity of neutrophil elastase reflects the progression of acute pancreatitis.

Objective: Neutrophil elastase (NE) concentration is associated with progression of acute pancreatitis (AP), but measuring total NE concentration includes biologically inactive NE. This study aims to investigate the relationship between NE activity and the aetiology and severity of AP and associated organ failure.

Methods: Seventy-five patients admitted to our surgery department with a first episode of AP during 2004-2005 were age- and sex-matched to 20 healthy volunteers (controls). NE activity was assessed using venous blood samples obtained on patient admission and after 1, 2 and 14 days. One sample was also taken from each control. ANOVA was used for statistical comparison between groups.

Results: Baseline NE activity (geometric mean; 95% confidence intervals) differed between patients (58.6 nM of substrate 7-amino-4-methylcoumarin [AMC]/hour; 48.52-70.72) and controls (31.5 nM AMC/hour; 25.5-39.0) (p = 0.0003), and did not correlate with time between symptom onset and admission. Patients with alcohol-induced AP demonstrated higher mean activity (59.1 nM AMC/h; 44.7-78.2) than those with gallstone-induced AP (41.7 nM AMC/h; 33.9-51.4) (p = 0.0496). NE activity was higher overall in patients with predicted severe AP (60.9 nM AMC/h; 48.0-77.2) than in those with predicted mild AP (42.1 nM AMC/h; 34.9-50.8) (p = 0.027). Patients with respiratory failure had higher NE activity (82.5 nM AMC/h; 57.5-118.4) than those without (43.9 nM AMC/h; 37.6-51.3) (p = 0.0024).

Conclusions: NE activity was associated with predicted severity of AP and AP-associated respiratory failure. Specific NE inhibitors may have therapeutic potential in acute pancreatitis.