Association between morphological features of necrotizing pancreatitis on endoscopic ultrasound and outcomes of the endoscopic transmural step-up approach.

Objective: To investigate the association between necrotic collections on endoscopic ultrasound (EUS) and outcomes of the endoscopic transmural step-up approach in necrotizing pancreatitis (NP).

Methods: Adult NP patients who had undergone endoscopic transmural step-up approach, endoscopic transmural drainage or endoscopic transmural necrosectomy, were retrospectively enrolled, and divided into groups 1, 2 and 3 based on the amount of solid necrotic debris (quantified as a percentage of the total collection size of <30%, 30%-50%, and >50%).

Results: A total of 134 patients were included, of whom 52, 59 and 23 patients were categorized into groups 1, 2 and 3. Patients with more solid necrotic debris required more necrosectomy sessions (group 3 vs group 2 vs group 1: 2.0 vs 1.0 vs 1.0, P < 0.001), were more likely to experience stent occlusion (group 3 vs group 2 vs group 1: 34.8% vs 16.9% vs 9.6%, P = 0.011), and had a longer hospitalization (group 3 vs group 2 vs group 1: 40.0 d vs 28.0 d vs 25.5 d, P = 0.015). High procalcitonin level (adjusted odds ratio [aOR] 6.14, 95% confidence interval [CI] 1.40-26.94, P = 0.016) and any organ failure (aOR 11.51, 95% CI 2.42-54.78, P = 0.002) were independently associated with clinical failure of endoscopic transmural step-up approach.

Conclusions: More solid necrotic debris on EUS is related to more necrosectomy sessions, higher incidence of stent occlusion and longer hospitalization. A nomogram combining procalcitonin and any organ failure performs well in predicting clinical failure of endoscopic transmural step-up approach.