Peter A. Banks

Classification of acute pancreatitis—2012: revision of the Atlanta classification and definitions by international consensus

Background and objective The Atlanta classification of acute pancreatitis enabled standardised reporting of research and aided communication between clinicians. Deficiencies identified and improved understanding of the disease make a revision necessary. Methods A web-based consultation was undertaken in 2007 to ensure wide participation of pancreatologists. After an initial meeting, the Working Group sent a draft document to 11 national and international pancreatic associations. This working draft was forwarded to all members. Revisions were made in response to comments, and the web-based consultation was repeated three times. The final consensus was reviewed, and only statements based on published evidence were retained. Results The revised classification of acute pancreatitis identified two phases of the disease: early and late. Severity is classified as mild, moderate or severe. Mild acute pancreatitis, the most common form, has no organ failure, local or systemic complications and usually resolves in the first week. Moderately severe acute pancreatitis is defined by the presence of transient organ failure, local complications or exacerbation of co-morbid disease. Severe acute pancreatitis is defined by persistent organ failure, that is, organ failure >48 h. Local complications are peripancreatic fluid collections, pancreatic and peripancreatic necrosis (sterile or infected), pseudocyst and walled-off necrosis (sterile or infected). We present a standardised template for reporting CT images. Conclusions This international, web-based consensus provides clear definitions to classify acute pancreatitis using easily identified clinical and radiologic criteria. The wide consultation among pancreatologists to reach this consensus should encourage widespread adoption.

Practice guidelines in acute pancreatitis.

Guidelines for clinical practice are intended to suggest preferable approaches to particular medical problems as established by interpretation and collation of scientifically valid research, derived from extensive review of published literature. When data are not available that will withstand objective scrutiny, a recommendation may be made based on a consensus of experts. Guidelines are intended to apply to the clinical situation for all physicians without regard to specialty. Guidelines are intended to be flexible, not necessarily indicating the only acceptable approach, and should be distinguished from standards of care that are inflexible and rarely violated. Given the wide range of choices in any health care problem, the physician should select the course best suited to the individual patient and the clinical situation presented. These guidelines are developed under the auspices of the American College of Gastroenterology and its practice parameters committee. These guidelines are also approved by the governing boards of the American Gastroenterological Association, American Society for Gastrointestinal Endoscopy, and American Association for the Study of Liver Diseases. Expert opinion is solicited from the outset for the document. Guidelines are reviewed in depth by the committee, with participation from experienced clinicians and others in related fields. The final recommendations are based on the data available at the time of the production of the document and may be updated with pertinent scientific developments at a later time. The following guidelines are intended for adults and not for pediatric patients.

Tumours of histiocytes and accessory dendritic cells: An immunohistochemical approach to classification from the International Lymphoma Study Group based on 61 cases

Tumours of histiocytes and accessory dendritic cells: an immunohistochemical approach to classification from the International Lymphoma Study Group based on 61 cases

Early diagnosis of pancreatic infection by computed tomography-guided aspiration

We performed 92 computed tomography-guided percutaneous needle aspirations of pancreatic inflammatory masses in 60 patients suspected of harboring pancreatic infection. Thirty-six patients (60%) were found by Gram stain and culture to have a total of 41 separate episodes of pancreatic infection. Among 42 aspirates judged to be infected by computed tomography-guided aspiration, all but one were confirmed by surgery or indwelling catheter drainage. Among 50 aspirates judged to be sterile, no subsequent evidence of infection was found. All patients tolerated the procedure well and no complications were noted. As a result of this technique, we observed that pancreatic infection occurs earlier than has been previously appreciated (within 14 days of the onset of pancreatitis in 20 of the 36 patients) and that infection may recur during prolonged bouts of pancreatitis. We conclude that guided aspiration is a safe, accurate method for identifying infection of the pancreas at an early stage.

Relationship of necrosis to organ failure in severe acute pancreatitis.

BACKGROUND & AIMS Pancreatic necrosis and organ failure are principal determinants of severity in acute pancreatitis. The purpose of this study was to determine the relationship of necrosis to organ failure in severe acute pancreatitis. METHODS Patients with necrotizing pancreatitis from May 1992 to January 1996 were retrospectively studied. Pancreatic necrosis was identified by characteristic findings on dynamic contrast-enhanced computerized tomography scan and infected necrosis by computerized tomography-guided percutaneous aspiration. Organ dysfunction was defined in accordance with the Atlanta symposium. RESULTS Organ failure was present in only 26 of 51 patients (51%). There was no difference in the prevalence of organ failure in infected necrosis compared with sterile necrosis (approximately 50% in both groups). Patients with increased amounts of necrosis did not have an increased prevalence of organ failure or infected necrosis compared with those with lesser amounts of necrosis. Patients with organ failure had an increased morbidity and mortality compared with those without organ failure. CONCLUSIONS Organ failure occurred in only one half of patients with necrotizing pancreatitis. Because organ failure increases the severity of illness, studies of patients with necrotizing pancreatitis must stratify for organ failure to facilitate interpretation of results.

The Early Prediction of Mortality in Acute Pancreatitis: A Large Population-based Study

Background: Identification of patients at risk for mortality early in the course of acute pancreatitis (AP) is an important step in improving outcome. Methods: Using Classification and Regression Tree (CART) analysis, a clinical scoring system was developed for prediction of in-hospital mortality in AP. The scoring system was derived on data collected from 17 992 cases of AP from 212 hospitals in 2000–2001. The new scoring system was validated on data collected from 18 256 AP cases from 177 hospitals in 2004–2005. The accuracy of the scoring system for prediction of mortality was measured by the area under the receiver operating characteristic curve (AUC). The performance of the new scoring system was further validated by comparing its predictive accuracy with that of Acute Physiology and Chronic Health Examination (APACHE) II. Results: CART analysis identified five variables for prediction of in-hospital mortality. One point is assigned for the presence of each of the following during the first 24 h: blood urea nitrogen (BUN) >25 mg/dl; impaired mental status; systemic inflammatory response syndrome (SIRS); age >60 years; or the presence of a pleural effusion (BISAP). Mortality ranged from >20% in the highest risk group to <1% in the lowest risk group. In the validation cohort, the BISAP AUC was 0.82 (95% CI 0.79 to 0.84) versus APACHE II AUC of 0.83 (95% CI 0.80 to 0.85). Conclusions: A new mortality-based prognostic scoring system for use in AP has been derived and validated. The BISAP is a simple and accurate method for the early identification of patients at increased risk for in-hospital mortality.

Hemoconcentration is an early marker for organ failure and necrotizing pancreatitis.

In a previous retrospective case-control study, hemoconcentration was associated with the development of pancreatic necrosis. The aim of the present study was to determine in a cohort study whether hemoconcentration is a marker for both organ failure and necrotizing pancreatitis. A cohort study was performed on patients admitted with acute pancreatitis from February 1996 to April 1997. Pancreatic necrosis was defined by findings on dynamic contrast-enhanced computed tomography scan or magnetic resonance imaging. Of 128 total patients with acute pancreatitis, 53 underwent computed tomography or magnetic resonance imaging. Eighteen of 53 had necrotizing pancreatitis. Logistic regression identified an admission hematocrit ≥44% and a failure of admission hematocrit to decrease at 24 hours as the best binary predictors of necrotizing pancreatitis and organ failure. By 24 hours, 17 of 18 patients with necrotizing pancreatitis versus 11 of 35 with interstitial pancreatitis met one or the other criterion for necrosis (p < 0.001). By 24 hours, 13 of 15 with organ failure versus 36 of 104 without organ failure met one or the other criterion (p < 0.001). The negative predictive value by 24 hours was 96% for necrotizing pancreatitis and 97% for organ failure. Hemoconcentration with an admission hematocrit ≥44% and/or failure of admission hematocrit to decrease at approximately 24 hours was associated with the development of necrotizing pancreatitis and organ failure. Patients who did not experience hemoconcentration were very unlikely to develop pancreatic necrosis or organ failure.

Necrotizing pancreatitis: Contemporary analysis of 99 consecutive cases

ObjectiveTo analyze the impact of a conservative strategy of management in patients with necrotizing pancreatitis, reserving intervention for patients with documented infection or the late complications of organized necrosis. Summary Background DataThe role of surgery in patients with sterile pancreatic necrosis remains controversial. Although a conservative approach is being increasingly used, few studies have evaluated this strategy when applied to the entire spectrum of patients with necrotizing pancreatitis. MethodsThe authors reviewed 1,110 consecutive patients with acute pancreatitis managed at Brigham and Women’s Hospital between January 1, 1995, and January 1, 2000, focusing on those with pancreatic necrosis documented by contrast-enhanced computed tomography. Fine-needle aspiration, the presence of extraintestinal gas on computed tomography, or both were used to identify infection. ResultsThere were 99 (9%) patients with necrotizing pancreatitis treated, with an overall death rate of 14%. In three patients with underlying medical problems, the decision was made initially not to intervene. Of the other 62 patients without documented infection, all but 3 were managed conservatively; this group’s death rate was 11%. Of these seven deaths, all were related to multiorgan failure. Five patients in this group eventually required surgery for organized necrosis, with no deaths. Of the 34 patients with infected necrosis, 31 underwent surgery and 3 underwent percutaneous drainage. Only four (12%) of these patients died, all of multiorgan failure. Of the total 11 patients who died, few if any would have been candidates for earlier surgical intervention. ConclusionsThese results suggest that conservative strategies can be applied successfully to manage most patients with necrotizing pancreatitis, although some will eventually require surgery for symptomatic organized necrosis. Few if any patients seem likely to benefit from a more aggressive strategy.

Lactated Ringer's Solution Reduces Systemic Inflammation Compared With Saline in Patients With Acute Pancreatitis

BACKGROUND & AIMS Aggressive fluid resuscitation is recommended for initial management of acute pancreatitis. We performed a randomized controlled trial to evaluate the impact of a goal-directed fluid resuscitation protocol on systemic inflammation in patients with acute pancreatitis. We then determined the impact of resuscitation with lactated Ringers solution, compared with normal saline. METHODS We performed a randomized controlled trial of 40 patients with acute pancreatitis at 3 New England hospitals from May 2009-February 2010. Patients received goal-directed fluid resuscitation with lactated Ringers solution, goal-directed fluid resuscitation with normal saline, standard fluid resuscitation with lactated Ringers solution, or standard fluid resuscitation with normal saline. Systemic inflammation was measured on the basis of levels of systemic inflammatory response syndrome (SIRS) and C-reactive protein (CRP) level after 24 hours. RESULTS The volumes of fluid administered during a 24-hour period were similar among patients given goal-directed or standard fluid resuscitation (mean, 4300 vs 4600 mL, respectively; P = .87). Goal-directed resuscitation did not significantly reduce incidence of SIRS, compared with standard resuscitation (11.8% vs 13.0%, respectively; P = .85) or levels of CRP after 24 hours (87.1 vs 69.2 mg/dL, respectively; P = .75). By contrast, there was a significant reduction in SIRS after 24 hours among subjects resuscitated with lactated Ringers solution, compared with normal saline (84% reduction vs 0%, respectively; P = .035); administration of lactated Ringers solution also reduced levels of CRP, compared with normal saline (51.5 vs 104 mg/dL, respectively; P = .02). CONCLUSIONS Patients with acute pancreatitis who were resuscitated with lactated Ringers solution had reduced systemic inflammation compared with those who received saline.

Prognostic factors in sterile pancreatic necrosis

Although the overall mortality in sterile pancreatic necrosis is low, patients who experience systemic complications may have a higher mortality. To study the impact of systemic complications and other factors on survival, possible prognostic factors were evaluated among 26 patients who experienced at least one systemic complication. Mortality was 38%. Factors that correlated with a fatal outcome were high Ransons scores during the first 48 hours (P = 0.01), high APACHE-II scores at admission (P = 0.04) and at 48 hours (P = 0.03), shock (P < 0.001), renal insufficiency (P < 0.05), multiple systemic complications (P < 0.001), and high body mass index (P = 0.01). Most systemic complications occurred during the first 2 weeks of illness. Logistic regression analysis showed that shock was the best predictor of a fatal outcome. Patients with favorable prognostic factors survived whether treated medically or surgically, whereas those with unfavorable factors had a fatal outcome whether treated medically or surgically. It is concluded that patients with severe sterile necrosis have a high mortality rate and that shock and other prognostic factors identify which patients are most likely to have a fatal outcome.