Extrapancreatic Necrosis Research Articles

The characteristics of acute necrotizing pancreatitis in different age stages: An MRI study

PurposeTo study the characteristics of acute necrotizing pancreatitis (ANP) in different age stages and their correlations with the clinical outcomes using magnetic resonance imaging (MRI). MethodMRI of 716 patients with acute pancreatitis was retrospectively reviewed to assess the incidence and characteristics of ANP. On MRI, ANP was classified into three subtypes: extrapancreatic necrosis (EPN) alone, pancreatic necrosis (PN) alone and combined necrosis. The extent of necrosis was also quantified on MRI. All patients were divided into three age groups, that is, young,middle-aged and elderly groups, and these characteristics of ANP were compared among the three age groups. The endpoints of patients' clinical outcome were compared among different age groups and different characteristics of ANP. ResultsOf the 716 patients, 129(18 %) were identified as ANP on MRI. The prevalence of ANP in the elderly group was the highest (28.9 %, p < 0.05). The patients in the middle-age and the elderly groups exhibited a higher risk of combined necrosis (56.9 %, 55.8 %; respectively), and elderly patients more frequently had extensive extrapancreatic involvement compared with young patients (65.9 % vs 21.4 %; p = 0.004); however, PN alone was more common in young patients. These characteristics of ANP were significantly bound up with clinical outcomes. ConclusionsDifferent subtypes of ANP have different outcomes. More importantly, age needs to be considered as a factor of special concern in development of ANP.

91 Colon Involvement in Necrotizing Pancreatitis—Incidence, Predictors and Outcomes From a Single Tertiary Care Center

INTRODUCTION: Colonic involvement significantly impacts the clinical course of necrotizing pancreatitis (NP) and reported in 6–40%. The spectrum of colonic complications includes fistula, strictures and ischemic colitis. The study aimed to determine the incidence, risk factors and clinical outcomes of colonic involvement of NP managed in our institution. METHODS: A retrospective analysis of all NP patients managed at our institution between 2010–2019 was performed from a prospectively maintained database for the occurrence of colonic complications. Baseline demographic characteristics, clinical presentation, management and outcomes were extracted. RESULTS: Colonic involvement occurred in 20 (3.9%) of the 515 NP patients managed during the study period, with colon fistulation detected in 12 (2.3%), strictures in 6 (1.2%) and ischemic colitis in 2 (0.4%). Males were predominantly involved [16 (80%)]. The median (range) age was 56 (23–84) years and alcohol was the main etiology of pancreatitis [10 (50%)]. All patients had extensive pancreatic and extra-pancreatic necrosis, with average BISAP score of 3 and modified Marshall score of 5. Infected necrosis noted in 18 (90%) patients. Subsequently, all underwent endoscopic and/or percutaneous drainage. Fistulae involved the left colon (mainly splenic flexure) in 9 (69.2%) and the right colon in 4 (30.8%) patients. While spontaneous closure occurred in 7 (53.8%); 4 (30.8%) were managed with over the scope clips and 2 (15.4%) surgically. Clinical outcomes were successful in 11 (92%) and all-cause mortality was 2 (17%). Colonic strictures and ischemia were managed conservatively in 3 (37.5%) subjects; 3 (37.5%) had stent placement, 1 (12.5%) underwent balloon dilation, and 1 (12.5%) underwent right sided hemicolectomy. Outcome was successful in all 8 (100%) patients. CONCLUSION: Male gender, obesity, alcohol etiology, infected necrosis, extensive pancreatic and extra-pancreatic involvement, and need for adjuvant percutaneous drainage may be predictors for development of colon complications in NP. Majority resolved conservatively after complete debridement of necrotic collection, some needed endoscopic management and very few needed surgical interventions.

Role of extrapancreatic necrosis volume in determining early prognosis in patients with acute pancreatitis.

This study aims to evaluate the capacity of the clinical and radiological findings and the extrapancreatic necrotic tissue volume in early (2-6days) computerized tomography (CT) images of patients diagnosed with AP to predict reliably the temporary or permanent organ failure and other local or systemic complications due to pancreatitis. Adult patients who were diagnosed with AP based on Revised Atlanta classification and underwent abdomen CT scans between May 2015 and May 2018 were examined retrospectively. Extrapancreatic necrosis volume was compared to various clinical parameters that indicate the prognosis of AP such as C-reactive protein (CRP) at 48-72th h, organ failure, infection, requirement for percutaneous or surgical intervention, length of hospital stay, and mortality, and to various imaging-based scoring systems such as the computerized tomography severity index (CTSI) and the modified CTSI (mCTSI). The receiver operating characteristic (ROC) curve was used to estimate the optimal threshold for predicting clinical prognosis. Extrapancreatic necrosis volume had moderate positive correlation with length of hospital stay (p = 0.0001) and CRP (at 48-72thh) (p = 0.0001) and strong positive correlation with CTSI (p = 0.0001), mCTSI (p = 0.0001), and white blood cell count (p = 0.0001). Extrapancreatic necrosis volume was found to be particularly better in predicting organ failure and infection compared to the imaging-based scoring systems (Balthazar, CTSI, and mCTSI) and the laboratory-based scoring systems (CRP at 48-72thh).

Su1430 – Isolated Extra-Pancreatic Necrosis is Associated with Better Clinical Outcomes Compared with Combined Pancreatic and Extrapancreatic Involvement: A Systematic Review and Meta-Analysis

Su1430 – Isolated Extra-Pancreatic Necrosis is Associated with Better Clinical Outcomes Compared with Combined Pancreatic and Extrapancreatic Involvement: A Systematic Review and Meta-Analysis

Impact of the site of necrosis on outcome of acute pancreatitis.

ObjecivesTo compare the clinical outcome of patients with extrapancreatic necrosis (EXPN) alone with that of acute interstitial pancreatitis (AIP), pancreatic parenchymal necrosis (PPN) alone, and combined PPN and EXPN.BackgroundThere are only a few studies in the literature in which EXPN has been recently recognized as a subtype of acute necrotizing pancreatitis (ANP), with a better prognosis.MethodsWe analyzed clinical data and outcome variables of 411 consecutive acute pancreatitis (AP) patients between January 2012 and December 2014. Contrast‐enhanced computed tomography (CECT) images of each patient were reviewed and characterized as AIP or ANP. Patients with ANP were divided into EXPN alone, PPN alone, and combined PPN and EXPN. Outcome variables were then compared between these groups.ResultsOf the 411 patients, 74 (18%) had AIP, and 337 (82%) had ANP. Patients with EXPN alone (n = 40; 11.8%) had similar outcomes as patients with PPN alone (n = 12; 3.5%); however, their outcome was worse than that of patients with AIP, with a higher frequency of persistent organ failure (POF), need for percutaneous catheter drainage (PCD), and longer length of hospitalization (LOH). Patients with combined PPN and EXPN (n = 285; 84.7%) had the worst clinical course, with higher frequency of POF, infected necrosis, intervention requirement, and longer LOH.ConclusionPatients with combined PPN and EXPN have a severe disease course with the worst clinical outcomes; patients with AIP patients have the most benign course, while patients with EXPN alone stand between the two extremes of disease course with an intermediate grade of severity.

Extrapancreatic necrosis with pancreatic (EXPN) intrapancreatic necrosis (INPN) predicts severity and local complications in acute pancreatitis better than isolated EXPN or INPN

Extrapancreatic necrosis with pancreatic (EXPN) intrapancreatic necrosis (INPN) predicts severity and local complications in acute pancreatitis better than isolated EXPN or INPN

Single incision laparoscopic surgery flank necrosectomy: A novel approach to extra-pancreatic walled off necrosis

Single incision laparoscopic surgery flank necrosectomy: A novel approach to extra-pancreatic walled off necrosis

Short article: Presence, extent and location of pancreatic necrosis are independent of aetiology in acute pancreatitis.

The most common aetiologies of acute pancreatitis (AP) are gallstones, alcohol and idiopathic. The impact of the aetiology of AP on the extent and morphology of pancreatic and extrapancreatic necrosis (EXPN) has not been clearly established. The aim of the present study was to assess the influence of aetiology on the presence and location of pancreatic necrosis in patients with AP. We carried out a post-hoc analysis of a previously established multicentre cohort of patients with AP in whom a computed tomography was available for review. Clinical data were obtained from the medical records. All computed tomographies were revised by the same expert radiologist. The impact of aetiology on pancreatic and EXPN was calculated. In total, 159 patients with necrotizing pancreatitis were identified from a cohort of 285 patients. The most frequent aetiologies were biliary (105 patients, 37%), followed by alcohol (102 patients, 36%) and other aetiologies including idiopathic (78 patients, 27%). No relationship was found between the aetiology and the presence of pancreatic necrosis, EXPN, location of pancreatic necrosis or presence of collections. We found no association between the aetiology of AP and the presence, extent and anatomical location of pancreatic necrosis.

Endoscopic or surgical step-up approach for infected necrotising pancreatitis: a multicentre randomised trial

Infected necrotising pancreatitis is a potentially lethal disease and an indication for invasive intervention. The surgical step-up approach is the standard treatment. A promising alternative is the endoscopic step-up approach. We compared both approaches to see whether the endoscopic step-up approach was superior to the surgical step-up approach in terms of clinical and economic outcomes. In this multicentre, randomised, superiority trial, we recruited adult patients with infected necrotising pancreatitis and an indication for invasive intervention from 19 hospitals in the Netherlands. Patients were randomly assigned to either the endoscopic or the surgical step-up approach. The endoscopic approach consisted of endoscopic ultrasound-guided transluminal drainage followed, if necessary, by endoscopic necrosectomy. The surgical approach consisted of percutaneous catheter drainage followed, if necessary, by video-assisted retroperitoneal debridement. The primary endpoint was a composite of major complications or death during 6-month follow-up. Analyses were by intention to treat. This trial is registered with the ISRCTN registry, number ISRCTN09186711. Between Sept 20, 2011, and Jan 29, 2015, we screened 418 patients with pancreatic or extrapancreatic necrosis, of which 98 patients were enrolled and randomly assigned to the endoscopic step-up approach (n=51) or the surgical step-up approach (n=47). The primary endpoint occurred in 22 (43%) of 51 patients in the endoscopy group and in 21 (45%) of 47 patients in the surgery group (risk ratio [RR] 0·97, 95% CI 0·62-1·51; p=0·88). Mortality did not differ between groups (nine [18%] patients in the endoscopy group vs six [13%] patients in the surgery group; RR 1·38, 95% CI 0·53-3·59, p=0·50), nor did any of the major complications included in the primary endpoint. In patients with infected necrotising pancreatitis, the endoscopic step-up approach was not superior to the surgical step-up approach in reducing major complications or death. The rate of pancreatic fistulas and length of hospital stay were lower in the endoscopy group. The outcome of this trial will probably result in a shift to the endoscopic step-up approach as treatment preference. The Dutch Digestive Disease Foundation, Fonds NutsOhra, and the Netherlands Organization for Health Research and Development.

To Prospectively Study the Outcome of Adult Patients With Acute Interstitial Pancreatitis, Acute Necrotizing Pancreatitis and Acute Pancreatitis With Extra-pancreatic Necrosis Alone

Introduction: The correlation between extent of extra pancreatic necrosis with disease outcome in patients with acute pancreatitis remains unclear and was assessed in this prospective study that looked at the natural course of patients with acute interstitial pancreatitis (AIP), acute necrotizing pancreatitis (ANP) and Extra-pancreatic necrosis (EPN) alone. Methods: Seventy eight patients of acute pancreatitis [55 (70.5%) males; mean age: 41.8 [range (16-77) years] were prospectively observed till clinical recovery or death. Contrast-enhanced computerized tomography of the abdomen was done after day 5 of onset of symptoms and patients were categorized into 3 groups: AIP, ANP and EPN alone. EPN was termed extensive if it extended to paracolic gutters and/or pelvis. All groups were compared with respect to outcomes (surgery/intervention, organ failure and mortality). Results: Ten (12.8%) patients had interstitial pancreatitis, fifty one (65%) had pancreatic necrosis (PN) alone or combined with EPN and ten patients (12.8%) had EPN alone. Forty four patients (56.4%) developed organ failure, whereas 42 (53.8%) had persistent organ failure. Forty patients (51.3%) underwent an intervention and thirteen patents (16.7%) expired. Patients with EPN alone had higher occurrence of organ failure (20 % vs 0%), persistent organ failures (20% vs 0%), and need for intervention [30% vs 0 %] as compared to patients with AIP. Patients in PN group had higher frequency of ascites (64.7% vs 50%), pleural effusion (88.23% vs 70%), multi organ failure (27.4% vs 0%), persistent organ failure (72.5% vs 20%), need for intervention (66.7% vs 30%) and mortality (25.5% vs 0 %) than patients with EPN alone. Similarly patients with extensive EPN (n = 40) had significantly higher frequency of ascites (75% vs 38.1%), organ failure(82.5% vs 28.6%), multi-organ failure( 35% vs 0%) and persistent organ failure (82.5% vs 28.6%) than patients with limited EPN. However mortality (27.5% vs 9.5%) and need for intervention (62.5% vs 57.1%) was comparable in both groups.Figure: Extrapancreatic necrosis.Figure: Walled off necrosis formed from acute necrotic collection (Extrapancreatic necrosis).Conclusion: Patients of EPN alone have a clinical course that is severe than AIP but milder than PN and hence should be considered as a separate category. Patients with extensive EPN despite having higher frequency of multi-organ failure, persistent organ failure, ascites and pleural effusion have comparable mortality or need for intervention compared to patients with limited EPN.Figure: Flowchart Depicting Local Complications and Intervention Amongst Pancreatitis Patients.

Extra-pancreatic necrosis volume as early predictor of severity in acute pancreatitis

Extra-pancreatic necrosis volume as early predictor of severity in acute pancreatitis

Analysis of risk factors related to gastrointestinal fistula in patients with severe acute pancreatitis: a retrospective study of 344 cases in a single Chinese center

BackgroundGastrointestinal fistula (GIF) in severe acute pancreatitis (SAP) is considered as a sparse episode and studied sporadically in the literature. There is paucity of data on the prediction of the effect on risk of GIF in patient with SAP. This study was aimed to investigate risk factors related to GIF in the development of SAP.MethodsThe clinical data of 344 patients with SAP from 2011 to 2016 were reviewed retrospectively. All patients were divided into the GIF group and the non-GIF group, and their data analyzed with respect to 15 parameters were applied to explore potential risk factors for GIF in patients with SAP.ResultsOf the 344 eligible patients, 52 (15.12%) progressed to GIF. Only occurrence of infected pancreatic and extra-pancreatic necrosis (IPN) (P = 0.004, OR = 3.012) and modified CT severity index (MCTSI) (P = 0.033, OR = 1.183) were proved to be independent risk factors for GIF in patients with SAP, and blood type B (P = 0.048, OR = 2.096, 95% CI: 0.748–3.562) indicated weaker association of risk factor for GIF. The early (48–72 h after admission) enteral nutrition (EEN) (P = 0.016, OR = 0.267) acted as a protective factor.ConclusionsOccurrence of IPN and high MCTSI are independent risk factors for the development of GIF in patients with SAP, blood type B reveals a potential correlation with GIF in patients with SAP. EEN is helpful to prevent the progression of GIF secondary to SAP.

Novedades en el manejo de la pancreatitis aguda

Acute pancreatitis (AP) is a potentially serious disease whose incidence is on the increase. Pancreas divisum does not meet the required criteria to be considered an aetiological factor. Sphincter of Oddi dysfunction may be another cause of idiopathic AP. Less invasive methods cannot replace Sphincter of Oddi manometry in diagnosis. Almost half of patients with systemic inflammatory response syndrome develop organ failure, but the mechanisms involved are not completely understood. Obesity is a risk factor for severity in AP; the cause could be the presence of free unsaturated fatty acids, which have pro-inflammatory activity. Prognosis is better in patients with isolated extra-pancreatic necrosis than in those with parenchymal necrosis or with both. The mortality rate among those with infected pancreatic necrosis is 15-20%. The “moderately severe” group is widely heterogeneous and this category may require redefinition. Laparoscopic treatment of pseudocysts is an alternative to endoscopic drainage and could be the first-line option in patients requiring cholecystectomy. The use of lumen-apposing metal stents to treat pancreatic necrosis is cost-effective. Quality of life in some patients following an attack of AP is significantly impaired even at 1 year. Aggressive fluid therapy is not superior to standard fluid therapy in preventing post-ERCP AP. The role of statins in AP prevention is still unclear. Aggressive fluid resuscitation and the use of lactated Ringer solution seem to be beneficial in the treatment of AP.

Significant inter-observer variation in the diagnosis of extrapancreatic necrosis and type of pancreatic collections in acute pancreatitis – An international multicenter evaluation of the revised Atlanta classification

BackgroundFor consistent reporting and better comparison of data in research the revised Atlanta classification (RAC) proposes new computed tomography (CT) criteria to describe the morphology of acute pancreatitis (AP). The aim of this study was to analyse the interobserver agreement among radiologists in evaluating CT morphology by using the new RAC criteria in patients with AP. MethodsPatients with a first episode of AP who obtained a CT were identified and consecutively enrolled at six European centres backwards from January 2013 to January 2012. A local radiologist at each center and a central expert radiologist scored the CTs separately using the RAC criteria. Center dependent and independent interobserver agreement was determined using Kappa statistics. ResultsIn total, 285 patients with 388 CTs were included. For most CT criteria, interobserver agreement was moderate to substantial. In four categories, the center independent kappa values were fair: extrapancreatic necrosis (EXPN) (0.326), type of pancreatitis (0.370), characteristics of collections (0.408), and appropriate term of collections (0.356). The fair kappa values relate to discrepancies in the identification of extrapancreatic necrotic material. The local radiologists diagnosed EXPN (33% versus 59%, P < 0.0001) and non-homogeneous collections (35% versus 66%, P < 0.0001) significantly less frequent than the central expert. Cases read by the central expert showed superior correlation with clinical outcome. ConclusionDiagnosis of EXPN and recognition of non-homogeneous collections show only fair agreement potentially resulting in inconsistent reporting of morphologic findings.

Extra-pancreatic necrosis alone: Contours of an emerging entity.

Acute pancreatitis is of two morphologic types: interstitial edematous pancreatitis that is not associated with any tissue necrosis and necrotizing pancreatitis wherein the pancreatic parenchyma with or without varying amount of extra-pancreatic tissue/fat undergoes necrosis. Necrotizing pancreatitis has a worse outcome compared with interstitial pancreatitis because of increased severity related to a heightened systemic response and cytokine storm associated with tissue necrosis. Increasingly, an entity of extra-pancreatic necrosis (EPN) alone, wherein the pancreatic parenchyma is normal on an enhanced computed tomographic scan but the peri-pancreatic tissues undergo necrosis, is being recognized. Available data suggest that the outcomes in patients with EPN alone are between the excellent prognosis of patients with interstitial and adverse prognosis of patients with necrotizing pancreatitis. The extent of EPN also seems to determine the outcome. This review summarizes the currently available literature on this entity and various radiological scores that have been suggested to determine the presence and stage of EPN.

Mo1406 Does Outcome of Isolated Extrapancreatic Necrosis (EPN) in Patients With Acute Pancreatitis Differs From Both Pancreatic Parenchymal Necrosis (PPN) and EPN? Single Center Experience

Mo1406 Does Outcome of Isolated Extrapancreatic Necrosis (EPN) in Patients With Acute Pancreatitis Differs From Both Pancreatic Parenchymal Necrosis (PPN) and EPN? Single Center Experience

Extrapancreatic necrosis is not uniformly identified by european radiologists - a prospective multicenter evaluation of the revised Atlanta classification

Extrapancreatic necrosis is not uniformly identified by european radiologists - a prospective multicenter evaluation of the revised Atlanta classification

Timing of catheter drainage in infected necrotizing pancreatitis.

Acute pancreatitis is the most common gastrointestinal indication for hospital admission, and infected pancreatic and/or extrapancreatic necrosis is a potentially lethal complication. Current standard treatment of infected necrosis is a step-up approach, consisting of catheter drainage followed, if necessary, by minimally invasive necrosectomy. International guidelines recommend postponing catheter drainage until the stage of 'walled-off necrosis' has been reached, a process that typically takes 4 weeks after onset of acute pancreatitis. This recommendation stems from the era of primary surgical necrosectomy. However, postponement of catheter drainage might not be necessary, and earlier detection and subsequent earlier drainage of infected necrosis could improve outcome. Strong data and consensus among international expert pancreatologists are lacking. Future clinical, preferably randomized, studies should focus on timing of catheter drainage in patients with infected necrotizing pancreatitis. In this Perspectives, we discuss challenges in the invasive treatment of patients with infected necrotizing pancreatitis, focusing on timing of catheter drainage.

Prognostic significance of differentiating necrosis from fluid collection on endoscopic ultrasound in patients with presumed isolated extrapancreatic necrosis.

BackgroundExtrapancreatic necrosis is diagnosed on computed tomography (CT) as extrapancreatic changes that are more than fat stranding; both fluid collections and necrosis would have a similar appearance. The aim of this study was to determine the prognostic significance of differentiating peripancreatic necrosis from fluid collection on endoscopic ultrasound (EUS) in patients with presumed isolated extrapancreatic necrosis.MethodsWe carried out a retrospective analysis of prospectively collected data from 36 patients (25 males; age range 19-65 years) with acute pancreatitis (AP) and isolated extrapancreatic necrosis. On EUS, peripancreatic anechoic areas were labeled as peripancreatic fluid collections and peripancreatic heterogeneously echotextured areas as peripancreatic necrosis.ResultsThe etiology of AP was alcohol in 16 (44.4%) patients, gallstone disease in 13 (36.1%), and other in 7 (19.4%). On EUS, 25 (69.4%) patients had peripancreatic necrosis and 11 (30.6%) patients had peripancreatic fluid collections. Compared with patients who had peripancreatic fluid collections, patients with peripancreatic necrosis had a significantly higher frequency of pleural effusion (88% vs. 55%; P=0.04), organ failure (OF) (68% vs. 27%; P=0.03), and persistent OF (48% vs. 9%; P=0.03). The patients with peripancreatic necrosis also had a higher frequency of ascites (20% vs. 9%), need for intervention (20% vs. nil), surgery (8% vs. nil) and mortality (8% vs. nil), but these differences were not statistically significant.ConclusionIsolated extrapancreatic necrosis on contrast-enhanced CT comprises a heterogeneous group, with patients who show peripancreatic fluid collections on EUS having a less severe disease course compared to patients with peripancreatic necrosis.

Clinical outcomes of combined necrotizing pancreatitis versus extrapancreatic necrosis alone.

Extrapancreatic necrosis (EPN) alone, i.e., in the absence of pancreatic parenchyma necrosis has gradually come to be regarded as a separate entity of acute necrotizing pancreatitis (ANP). However, data regarding the prognostic significance of EPN are quite limited, and the outcomes of interventions for patients with EPN alone are not well elucidated. The aim of this study was to explore the differences in the outcomes of patients with EPN alone and patients with both the pancreatic parenchyma and extrapancreatic necrosis (combined necrosis). From January 2009 to December 2013, a total of 334 patients with ANP who had received interventions in the West China Hospital in China were included. Based on the extent of necrosis as assessed with contrast-enhanced CT, the patients were divided into Group 1 (n = 285) in which the necrosis involved both the pancreatic parenchyma and extrapancreatic tissues (combined necrosis) and Group 2 (n = 49) in which the necrosis involved only the extrapancreatic tissues. Additionally, Group 3 included 443 patients with interstitial pancreatitis who were also included in the analyses. The demographic characteristics, support treatment information, organ failure information, infection necrosis, persistent systemic inflammatory response syndrome (SIRS) in the first week of onset, CT severity index, and intervention types, as well as the postoperative stay lengths, ICU utility, and complications were collected and compared. Compared with the patients in Group 1, the patients in Group 2 suffered less persistent SIRS in the first week of onset (12/24.5% vs. 145/50.9%; P < 0.05), less persistent organ failure (6/12.2% vs. 95/33.3%; P < 0.05), less persistent multiple organ failure (3/6.1% vs. 67/23.5%; P < 0.05), and less bacteremia (5/10.2% vs. 107/37.5%; P < 0.001). The intervention types were significantly different between the two groups (P < 0.001); initial open necrosectomy was performed in 174/61.6% and 8/16.3% of the patients in Groups 1 and 2, respectively, and initial percutaneous catheter drainage (PCD) was performed in 73/25.6% and 29/59.2% of the patients in the two respective groups. Second open necrosectomies following PCD were required in 61/83.5% and 9/31.0% of the patients in Groups 1 and 2, respectively (P < 0.001). A greater number of patients in Group 1 were diagnosed with infected necrosis (204/71.6% vs. 10/20.4%; P < 0.001) and had to be sent to the ICU for further postoperative care (221/77.5% vs. 23/46.9%; P < 0.001). The postoperative stay was longer for Group 1 (median: 43.0 vs. 26.5 days; P < 0.001). Residual necrotic tissue or abscess was the most common postoperative complication in both groups. The mortality was higher in Group 1 (52/18.2% vs. 1/2.1%; P < 0.05). Compared with the patients in Group 2, the patients with interstitial pancreatitis exhibited milder courses and better outcomes. Subgroup comparisons with Group 1 indicated that early multiple organ failure was significantly associated with higher mortality. The patients with EPN alone exhibited significantly better prognoses than those with combined necrosis, and EPN alone should be regarded as a separate group of acute necrotizing pancreatitis. Open necrosectomy can be avoided in the majority of patients with EPN alone, who receive PCD as the initial first intervention.