Several interventional and surgical procedures are available to treat moderate-to-critical acute pancreatitis (AP) in its late phase. The ongoing debate on these options, together with the scarcity of reported mid-term follow-up information in the Literature, prompted the investigators to conduct a review of our surgical experience, focused on those issues. The investigators reviewed retrospectively all the patients treated for moderate-to-critical AP according to Determinant-Based Classification (DBC), in the last nine years. Patients treated conservatively or operated within 4 weeks of the onset of the pancreatitis were excluded. All the included patients were managed following a "tailored" step-up approach, and divided into four groups, according to the first interventional procedure performed: percutaneous drainage (PD), endoscopic approach (END), internal derivation (INT), and necrosectomy (NE). In-hospital and mid-term follow-up variables, including a quality-of-life assessment, were analyzed and compared.

The following variables were evaluated: sex, age, severity of inflammation according to the DBC classification, PA etiology, CT scan severity index according to Balthazar criteria , clinical prognostic score using bedside index of severity of acute pancreatitis (BISAP) score.

Total length of hospitalization, operative management, necrosis cultures, total and post-interventional Intensive Unit Care (ICU) were also recorded and analyzed together with the in-hospital morbidity, mortality and re-admissions.

Patients were checked after discharge within 14 days and followed monthly as outpatients by gastroenterologists. A CT scan was performed within 4 months, or before in case of recurrent symptoms. During the follow-up, the English Standard Short Form 36 (SF-36) questionnaire was used to evaluate the general quality of life at three and six months, one and two years. The SF-36 examines 8 areas consisting of social and physical function, physical and emotional well-being, bodily pain, vitality, mental health and overall general health perception. At the six-month follow-up, the patients also completed a specific questionnaire about the pancreatic function. In particular, the total score takes in consideration abdominal pain using visual analogue pain score, diarrhea, unintentional weight loss, new onset of diabetes and use of enzyme supplementation. The score ranges between zero to five (all symptoms present). The work has been reported in line with the STROCSS criteria

Inclusion Criteria:

• patients treated at our referral Center for moderate to critical AP, as classified by Determinant-Based Classification of Acute Pancreatitis Severity

Exclusion Criteria:

• patients who had undergone conservative treatment,
• patients who has been operated within 4 weeks (early phase)

The cohort sample was divided into four groups, according to the first type of the interventional or surgical management performed