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.

BACKGROUND: For 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. METHODS: Patients 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. RESULTS: In 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. CONCLUSION: Diagnosis of EXPN and recognition of non-homogeneous collections show only fair agreement potentially resulting in inconsistent reporting of morphologic findings.

Pleuropulmonary pathologies in the early phase of acute pancreatitis correlate with disease severity.

BACKGROUND: Respiratory failure worsens the outcome of acute pancreatitis (AP) and underlying factors might be early detectable. AIMS: To evaluate the prevalence and prognostic relevance of early pleuropulmonary pathologies and pre-existing chronic lung diseases (CLD) in AP patients. METHODS: Multicentre retrospective cohort study. Caudal sections of the thorax derived from abdominal contrast enhanced computed tomography (CECT) performed in the early phase of AP were assessed. Independent predictors of severe AP were identified by binary logistic regression analysis. A one-year survival analysis using Kaplan-Meier curves and log rank test was performed. RESULTS: 358 patients were analysed, finding pleuropulmonary pathologies in 81%. CECTs were performed with a median of 2 days (IQR 1-3) after admission. Multivariable analysis identified moderate to severe or bilateral pleural effusions (PEs) (OR = 4.16, 95%CI 2.05-8.45, p<0.001) and pre-existing CLD (OR = 2.93, 95%CI 1.17-7.32, p = 0.022) as independent predictors of severe AP. Log rank test showed a significantly worse one-year survival in patients with bilateral compared to unilateral PEs in a subgroup. CONCLUSIONS: Increasing awareness of the prognostic impact of large and bilateral PEs and pre-existing CLD could facilitate the identification of patients at high risk for severe AP in the early phase and thus improve their prognosis.

Mean muscle attenuation correlates with severe acute pancreatitis unlike visceral adipose tissue and subcutaneous adipose tissue.

Background: Acute pancreatitis (AP) is a frequent disorder with considerable morbidity and mortality. Obesity has previously been reported to influence disease severity. Objective: The aim of this study was to investigate the association of adipose and muscle parameters with the severity grade of AP. Methods: In total 454 patients were recruited. The first contrast-enhanced computed tomography of each patient was reviewed for adipose and muscle tissue parameters at L3 level. Associations with disease severity were analysed through logistic regression analysis. The predictive capacity of the parameters was investigated using receiver operating characteristic (ROC) curves. Results: No distinct variation was found between the AP severity groups in either adipose tissue parameters (visceral adipose tissue and subcutaneous adipose tissue) or visceral muscle ratio. However, muscle mass and mean muscle attenuation differed significantly with p-values of 0.037 and 0.003 respectively. In multivariate analysis, low muscle attenuation was associated with severe AP with an odds ratio of 4.09 (95% confidence intervals: 1.61-10.36, p-value 0.003). No body parameter presented sufficient predictive capability in ROC-curve analysis. Conclusions: Our results demonstrate that a low muscle attenuation level is associated with an increased risk of severe AP. Future prospective studies will help identify the underlying mechanisms and characterise the influence of body composition parameters on AP.

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

OBJECTIVE: 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. PATIENTS AND METHODS: 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. RESULTS: 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. CONCLUSION: We found no association between the aetiology of AP and the presence, extent and anatomical location of pancreatic necrosis.