Urinary trypsinogen-2 level and local complications of acute pancreatitis

Background and aim: Local complications of acute pancreatitis (AP) carry risks of morbidity/mortality. This study aimed to assess whether urinary trypsinogen-2 levels and Bedside Index for Severity in Acute Pancreatitis (BISAP) score on admission predicted subsequent local complications.

Methods: One hundred and forty-four consecutive patients with AP were prospectively followed till 6 months after discharge. Urinary trypsinogen-2 levels were measured within 24 h of admission. Local complications (acute peripancreatic fluid collection, acute necrotic collection, pseudocyst, and walled-off necrosis) were diagnosed by abdominal computed tomography. Cut-off for trypsinogen-2 level was assessed using receiver operating characteristic curve, and predictors of local complications were analyzed by logistic regression.

Results: Thirty-seven (25.7%) patients developed local complications. Urinary trypsinogen-2 levels were significantly higher in patients with local complications compared with those without local complications (median [interquartile range], 3210 [620-9764.4] μg/L vs 627.3 [72.3-5895] μg/L, P = 0.006). Urinary trypsinogen-2 significantly outperformed BISAP score in predicting local complications (area under the receiver operating characteristic curve 0.65 [95% CI: 0.55-0.75] vs 0.48 [95% CI: 0.38-0.58], P = 0.005). At the optimal cut-off of 500 μg/L, the sensitivity, specificity, positive predictive value, and negative predictive value of trypsinogen-2 level were 78.4%, 45.8%, 33.3%, and 86.0%, respectively. Urinary trypsinogen-2 level > 500 μg/L was an independent predictor of local complications (adjusted odds ratio, 3.72; 95% CI: 1.42-9.76; P = 0.007). By contrast, BISAP score ≥ 3 and pleural effusion predicted organ failure but not local complications.

Conclusion: In a prospective cohort, urinary trypsinogen-2 level > 500 μg/L independently predicted local complications of AP.