Update on acute pancreatitis: ultrasound, computed tomography, and magnetic resonance imaging features

Cross-sectional imaging after pancreatic surgery: The dialogue between the radiologist and the surgeon

Pancreatic surgery is nowadays considered one of the most complex surgical approaches and not unscathed from complications. After the surgical procedure, cross-sectional imaging is considered the non-invasive reference standard to detect early and late compilations, and consequently to address patients to the best management possible. Contras-enhanced computed tomography (CECT) should be considered the most important and useful imaging technique to evaluate the surgical site. Thanks to its speed, contrast, and spatial resolution, it can help reach the final diagnosis with high accuracy. On the other hand, magnetic resonance imaging (MRI) should be considered as a second-line imaging approach, especially for the evaluation of biliary findings and late complications. In both cases, the radiologist should be aware of protocols and what to look at, to create a robust dialogue with the surgeon and outline a fitted treatment for each patient.

Pancreatic Iodine Density and Fat Fraction on Dual-Energy Computed Tomography in Acute Pancreatitis

The aim of our study was to investigate iodine density (ID) and fat fraction (FF) on dual-energy computed tomography (DECT) in patients with acute pancreatitis (AP). This retrospective study included 72 patients with clinically confirmed AP and 62 control subjects with DECT of the abdomen. Two radiologists assessed necrosis and measured attenuation values, ID, and FF in three pancreatic segments. We used receiver operating characteristic (ROC) analysis to determine the optimal threshold for ID for the differentiation between AP groups. The ID was significantly higher in interstitial edematous AP compared to necrotizing AP and the control group (both p < 0.05). The ROC curve analysis revealed the thresholds of ID for detecting pancreatic necrosis ≤ 2.2, ≤2.3, and ≤2.4 mg/mL (AUC between 0.880 and 0.893, p > 0.05) for the head, body, and tail, respectively. The FF was significantly higher for pancreatitis groups when compared with the control group in the head and body segments (both p < 0.001). In the tail, the difference was significant in necrotizing AP (p = 0.028). The ID values were independent of attenuation values correlated with the FF values in pancreatic tissue. Iodine density values allow for differentiation between morphologic types of AP.

The pathogenic mutations of APOA5 in Chinese patients with hyperlipidemic acute pancreatitis

BACKGROUND AND AIMS

To study the role of gene mutations in the development of severe hypertriglyceridemia (HTG) in patients with hyperlipidemic acute pancreatitis (HLAP), especially different apolipoprotein A5 (APOA5) mutations.

METHODS

Whole-exome sequencing was performed on 163 patients with HLAP and 30 patients with biliary acute pancreatitis (BAP). The pathogenicity of mutations was then assessed by combining clinical information, predictions of bioinformatics programs, information from multiple gene databases, and residue location and conservation. The pathogenic mutations of APOA5 were visualized using the software.

RESULTS

1. Compared with BAP patients, pathogenic mutations of APOA5 were frequent in HLAP patients; among them, the heterozygous mutation of p.G185C was the most common. 2. All six pathogenic mutations of APOA5 identified in this study (p.S35N, p.D167V, p.G185C, p.K188I, p.R223C, and p.H182fs) were positively correlated with severe HTG; they were all in the important domains of apolipoprotein A-V (apoA-V). Residue 223 is strictly conserved in multiple mammals and is located in the lipoprotein lipase (LPL)-binding domain (Pro215-Phe261). When Arg 223 is mutated to Cys 223, the positive charge of this residue is reduced, which is potentially destructive to the binding function of apoA-V to LPL. 3. Four new APOA5 mutations were identified, namely c.563A > T, c.667C > T, c.788G > A, and c.544_545 insGGTGC.

CONCLUSIONS

The pathogenic mutations of APOA5 were specific to the patients with HLAP and severe HTG in China, and identifying such mutations had clinical significance in elucidating the etiology and subsequent treatment.

Diagnosis of Acute Pancreatitis Using Postmortem Computed Tomography and Postmortem Magnetic Resonance Imaging: A Case Report and a Review of Literature

ABSTRACT

Acute pancreatitis (AP) is inflammation of the pancreas, which may be due to a wide variety of etiologies that share a final common pathway of premature activation of pancreatic enzymes and resultant autodigestion of pancreatic parenchyma. Acute pancreatitis is easy to diagnose clinically, with the presence of at least 2 of the 3 criteria (upper abdominal pain, serum amylase or lipase level greater than 3 times the upper limit of normal, or characteristic findings on imaging studies) of the revised Atlanta classification. However, postmortem imaging examinations of pancreatitis are extremely rare, and very few successful cases have been reported. Here, we present a case report of a single patient who underwent autopsy and postmortem imaging. Postmortem computed tomography (PMCT) and postmortem magnetic resonance imaging (PMMRI) showed peripancreatic inflammation and acute peripancreatic fluid collection in the left anterior pararenal space, which is consistent with the examination by autopsy. The advantages of PMMRI in AP have also been demonstrated. Our study also confirmed the advantage of PMCT angiography in the diagnosis of AP. To the best of our knowledge, this is the first report of PMCT and PMMRI combined with postmortem pathology in the diagnosis of AP.

Acute pancreatitis: A review of diagnosis, severity prediction and prognosis assessment from imaging technology, scoring system and artificial intelligence

Acute pancreatitis (AP) is a potentially life-threatening inflammatory disease of the pancreas, with clinical management determined by the severity of the disease. Diagnosis, severity prediction, and prognosis assessment of AP typically involve the use of imaging technologies, such as computed tomography, magnetic resonance imaging, and ultrasound, and scoring systems, including Ranson, Acute Physiology and Chronic Health Evaluation II, and Bedside Index for Severity in AP scores. Computed tomography is considered the gold standard imaging modality for AP due to its high sensitivity and specificity, while magnetic resonance imaging and ultrasound can provide additional information on biliary obstruction and vascular complications. Scoring systems utilize clinical and laboratory parameters to classify AP patients into mild, moderate, or severe categories, guiding treatment decisions, such as intensive care unit admission, early enteral feeding, and antibiotic use. Despite the central role of imaging technologies and scoring systems in AP management, these methods have limitations in terms of accuracy, reproducibility, practicality and economics. Recent advancements of artificial intelligence (AI) provide new opportunities to enhance their performance by analyzing vast amounts of clinical and imaging data. AI algorithms can analyze large amounts of clinical and imaging data, identify scoring system patterns, and predict the clinical course of disease. AI-based models have shown promising results in predicting the severity and mortality of AP, but further validation and standardization are required before widespread clinical application. In addition, understanding the correlation between these three technologies will aid in developing new methods that can accurately, sensitively, and specifically be used in the diagnosis, severity prediction, and prognosis assessment of AP through complementary advantages.

Acute peripancreatic fluid collection in acute pancreatitis: Incidence, outcome, and association with inflammatory markers

Background

The hospital outcomes and predictors of acute peripancreatic fluid collection (APFC) have not been well-characterized. In this study, we aimed to investigate the clinical outcomes of APFC in patients with acute pancreatitis (AP) and the role of the systemic immune-inflammation index (SII), systemic inflammation response index (SIRI), and C-reactive protein (CRP) level in predicting the occurrence of APFC.

Methods

In this retrospective study, the complicated group (patients with APFC) and the uncomplicated group (patients without APFC) were compared for their clinical characteristics, hospital outcomes (mortality rate, intensive care unit admission rate, and length of hospital stay), pseudocyst formation, CRP levels, SII, and SIRI on admission and at 48 hours.

Results

Of 132 patients with AP, 51 (38.6%) had APFC and eight (6.1%) had pancreatic pseudocysts. Of 51 patients with APFC, 15.7% had pancreatic pseudocysts. Pseudocyst did not develop in the uncomplicated group. SII value at 48 h [median 859 (541-1740) x 109/L vs. 610 (343-1259) x 109/L, P = 0.01] and CRP level at 48 h [89 (40-237) mg/L vs. 38 (12-122) mg/L, P = 0.01] were higher in the complicated group than in the uncomplicated group. The length of hospital stay was longer in the complicated group, compared with the uncomplicated group [median 8 days (5-15), vs. 4 days (3-7), P < 0.001, respectively]. No significant difference was detected between the two study groups' mortality rates and intensive care unit admission rates.

Conclusions

While 38.6% of the AP patients had APFC, 6.1% of all patients and 15.7% of the patients with APFC had pancreatic pseudocysts. APFC was found to lengthen the hospital stay and to be associated with the SII value and CRP level measured at 48 h.

Involvement of transverse mesocolon is associated with development of colonic fistula in patients with acute necrotizing pancreatitis

BACKGROUND

Involvement of transverse mesocolon (TM) during acute necrotizing pancreatitis(ANP) indicates that inflammation has spread from retroperitoneal space to peritoneum. Nevertheless, the impact of TM involvement, as confirmed by contrast-enhanced computed tomography (CECT), on local complications and clinical outcomes was poorly investigated.

PURPOSE

This study aimed to explore the association between CECT-diagnosed TM involvement and the development of colonic fistula in a cohort of ANP patients.

METHODS

This is a single-center, retrospective cohort study involving ANP patients admitted from January 2020 to December 2020. TM involvement was diagnosed by two experienced radiologists. The study subjects were enrolled consecutively and divided into two groups: TM involvement and non-TM involvement. The primary outcome was colonic fistula during the index admission. Clinical outcomes were compared between the two groups, and the association between the TM involvement and the development of colonic fistula was assessed using multivariable analysis to adjust for baseline unbalances.

RESULTS

A total of 180 patients with ANP were enrolled, and 86 (47.8%) patients had TM involvement. The incidence of the colonic fistula is significantly higher in patients with TM involvement (16.3% vs. 5.3%;p = 0.017). Moreover, the length of hospital stay was 24(13,68) days in patients with TM involvement and 15(7,31) days in those not (p = 0.001). Analysis of multivariable logistic regression revealed that TM involvement is an independent risk factor for the development of colonic fistula (odds ratio: 10.253, 95% CI: 2.206-47.650, p = 0.003).

CONCLUSION

TM involvement in ANP patients is associated with development of colonic fistula in ANP patients.

Predisposing Factors and Neurologic Outcomes of Patients with Elevated Serum Amylase and/or Lipase after Out-of-Hospital Cardiac Arrest: A Retrospective Cohort Study

This study investigated the patient outcomes, incidence, and predisposing factors of elevated pancreatic enzyme levels after OHCA. We conducted a retrospective cohort study of patients treated with targeted temperature management (TTM) after out-of-hospital cardiac arrest (OHCA). Elevation of pancreatic enzyme levels was defined as serum amylase or lipase levels that were at least three times the upper limit of normal. The factors associated with elevated pancreatic enzyme levels and their association with neurologic outcomes and mortality 28 days after OHCA were analyzed. Among the 355 patients, 166 (46.8%) patients developed elevated pancreatic enzyme levels. In the multivariable analysis (odds ratio, 95% confidence interval), initial shockable rhythm (0.62, 0.39−0.98, p = 0.04), time from collapse to return of spontaneous circulation (1.02, 1.01−1.04, p < 0.001), and history of coronary artery disease (1.7, 1.01−2.87, p = 0.046) were associated with elevated pancreatic enzyme levels. After adjusting for confounding factors, elevated pancreatic enzyme levels were associated with neurologic outcomes (5.44, 3.35−8.83, p < 0.001) and mortality (3.74, 2.39−5.86, p < 0.001). Increased pancreatic enzyme levels are common in patients treated with TTM after OHCA and are associated with unfavorable neurologic outcomes and mortality at 28 days after OHCA.

Oxid Comparative Analysis of the Significance of Bisap and Mews Score for an Early Assessment of Illness Severity and Treatment Outcome of Acute Pancreatitis

The aim of this study was to determine the significance of the use of the BISAP score, which is specific for patients with AP, in relation to the application of the MEWS score that is important for assessing the condition of critically ill patients in intensive care units, but is not specific for patients with AP. The research was conducted as a cohort prospective study and included patients of both sexes, older than 18 and diagnosed with AP. BISAP and MEWS score were monitored at least at four time points: on admission to the hospital (zero), 48 hours, 72 hours and 7 days after admission to the hospital.

High levels of discrimination between patients with fatal outcome and cured patients are determined in both cases, with discrimination at MEWS being somewhat higher than BISAP score. The BISAP0 had the best discrimination for BISAP score, AUROC (0.807) and also MEWS0 for MEWS score, AUROC (0.899). In our research, the highest sensitivity was shown by BISAP7d (92.1%) and MEWS48 (88.1%), and a high specificity of 87.5% had BISAP score, 48h, 72h and MEWS score at all four points of measurement.

BISAP score has a better prognostic value in relation to the form of pancreatitis, the development of complications and the outcome. However, the calculation of the MEWS score is based on monitoring the basic vital parameters so that its application is much simpler and does not require additional costs.

The role of imaging in acute pancreatitis

Acute pancreatitis is one of the most commonly encountered etiologies in the emergency setting, with a broad spectrum of findings that varies in severity from mild interstitial pancreas to severe forms with significant local and systemic complications that are associated with a substantial degree of morbidity and mortality. In this article the radiological aspect of the terminology and classification of acute pancreatitis are reviewed. The roles of ultrasound, computed tomography, and magnetic resonance imaging in the diagnosis and evaluation of acute pancreatitis and its complications are discussed. The authors present a practical image-rich guide, applying the revised Atlanta classification system, with the goal of facilitating radiologists to write a correct report, and reinforcing the radiologist’s role as a key member of a multidisciplinary team in treating patients with acute pancreatitis. Computed tomography is the most performed imaging test for acute pancreatitis. Nevertheless, MRI is useful in many specific situations, due to its superiority soft tissue contrast resolution and better assessment of biliary and pancreatic duct, for example in the ductal disconnection. The purpose if this article is to review recent advances in imaging acquisition and analytic techniques in the evaluation of AP.

Pancreatitis and PDAC: association and differentiation

The discrimination of mass-forming chronic pancreatitis (MFCP) from pancreatic ductal adenocarcinoma (PDAC) is a central diagnostic dilemma. It is important to differentiate these entities since they have markedly different prognoses and management. Importantly, the appearance of these two entities significantly overlaps on a variety of imaging modalities. However, there are imaging features that may be suggestive of one entity more than the other. MFCP and PDAC may show different enhancement patterns on perfusion computed tomography (CT) and/or dynamic contrast-enhanced MRI (DCE-MRI). The duct-penetrating sign on magnetic resonance cholangiopancreatography (MRCP) is more often associated with MFCP, whereas abrupt cutoff with upstream dilatation of the main pancreatic duct and the double-duct sign (obstruction/cutoff of both the common bile duct and pancreatic duct) are more often associated with PDAC. Nevertheless, tissue sampling is the most reliable method to differentiate between these entities and is currently generally necessary for management.

Utility of ultrasound in acute pancreatitis

Ultrasound plays an essential role in the initial evaluation of patients with suspected or confirmed acute pancreatitis. In addition to evaluation of the pancreatic parenchyma, ultrasound is used for assessment of the gallbladder, biliary tree, peripancreatic tissues, and regional vascular structures. While enlarged and edematous pancreas are classic sonographic features of acute pancreatitis, the pancreas may appear sonographically normal in the setting of acute pancreatitis. Nonetheless, sonographic evaluation in this setting is valuable because assessment for etiologic factors such as gallstones or evidence of biliary obstruction are best performed with ultrasound. Complications of pancreatitis such as peripancreatic fluid collections, venous thrombosis, or arterial pseudoaneurysm can be identified with careful and focused ultrasound examination. Knowledge of various scanning techniques can help to mitigate some of the commonly encountered barriers to sonographic visualization of the pancreas and right upper quadrant structures. Ultrasound can also be used for guidance of percutaneous treatment such as drainage of fluid collections or pseudoaneurysm thrombosis. Difficulty in differentiating edematous from necrotizing pancreatitis can be mitigated with the use of contrast-enhanced ultrasound to assess pancreatic parenchymal enhancement.

Prediction of Necrotizing Pancreatitis on Early CT Based on the Revised Atlanta Classification

Purpose

To investigate the clinical and CT features at admission to predict the progression to necrotizing pancreatitis (NP) in patients initially diagnosed with interstitial edematous pancreatitis (IEP).

Materials and Methods

Patients with IEP who underwent contrast-enhanced CT at admission and follow-up CT (< 14 days) were included (n = 178). Two radiologists performed a consensus review of follow-up CT scans and diagnosed the type of acute pancreatitis as IEP or NP. Laboratory findings at admission were recorded. Clinical, CT, and laboratory findings were compared between the IEP-IEP group and IEP-NP group using the chi-square test and the t-test. Multivariate analysis was also performed.

Results

There were 112 and 66 patients in the IEP-IEP and the IEP-NP groups, respectively. The proportion of patients with alcohol etiology was significantly larger in the IEP-NP group. Among the CT findings, the presence of peripancreatic fluid and heterogeneous parenchymal enhancement were more frequently observed in the IEP-NP group. Among the laboratory variables, serum C-reactive protein levels and white blood cell counts were significantly higher in the IEP-NP group. Multivariate analysis revealed that the presence of peripancreatic fluid and heterogeneous parenchymal enhancement were significant findings distinguishing the two groups.

Conclusion

CT findings, such as the presence of peripancreatic fluid and heterogeneous pancreatic parenchymal enhancement, may be helpful in predicting the progression to NP in patients initially diagnosed with IEP.

Risk factors for chronic and recurrent pancreatitis after first attack of acute pancreatitis

OBJECTIVE

To study the outcome of acute pancreatitis and risk factors for recurrent and chronic pancreatitis in a population based cohort of patients with first-time acute pancreatitis.

METHODS

All patients with first-time acute pancreatitis from 2006-2015 in Iceland were retrospectively evaluated. Medical records were scrutinized and relevant data extracted.

RESULTS

1102 cases of first-time acute pancreatitis were identified: mean age 56yr, 46% female, 41% biliary, 21% alcohol, 26% idiopathic, 13% other causes, mean follow-up 4yr. 21% had ≥1 recurrent acute pancreatitis which was independently related to alcoholic (vs. biliary hazard ratio (HR) 2.29, 95% confidence interval (CI) 1.51-3.46), male gender (HR 1.48, 95%CI 1.08-2.04), and smoking (HR 1.62, 95%CI 1.15-2.28). 3.7% developed chronic pancreatitis. Independent predictors were recurrent acute pancreatitis (HR 8.79, 95%CI 3.94-19.62), alcoholic (vs. biliary HR 9.16, 95%CI 2.71-30.9), local complications (HR 4.77, 95%CI 1.93-11.79), and organ-failure (HR 2.86, 95%CI 1.10-7.42).

CONCLUSIONS

Recurrent acute pancreatitis occurred in one-fifth of patients. Development of chronic pancreatitis was infrequent. Both recurrent acute pancreatitis and chronic pancreatitis were related to alcoholic acute pancreatitis, while recurrent acute pancreatitis was associated with smoking and male gender, and chronic pancreatitis to recurrent acute pancreatitis, organ-failure, and local complications.

Hemolytic Uremic Syndrome: An Increasingly Recognized Public Health Problem

A 28-year-old man was referred and admitted to our hospital due to Escherichia coli O157-mediated hemorrhagic colitis with severe thrombocytopenia. A systemic workup concluded that the patient had acute pancreatitis as well as hemolytic uremic syndrome. The patient was ultimately discharged, with his platelet count having recovered. Our case serves an illustrative example of potentially serious complications of an increasingly recognized public health problem. Systemic studies on this topic are insufficient, and we strongly recommend the further accumulation of more experiences like ours. Several diagnostic and management concerns that emerged in this case are also discussed.

Classification of Acute Pancreatitis in the Pediatric Population: Clinical Report From the NASPGHAN Pancreas Committee

INTRODUCTION

Acute pancreatitis (AP) is an emerging problem in pediatrics, with most cases resolving spontaneously. Approximately 10% to 30%, however, are believed to develop "severe acute pancreatitis" (SAP).

METHODS

This consensus statement on the classification of AP in pediatrics was developed through a working group that performed an evidence-based search for classification of AP in adult pancreatitis, definitions and criteria of systemic inflammatory response syndrome, and organ failure in pediatrics.

RESULTS AND DISCUSSION

Severity in pediatric AP is classified as mild, moderately severe, or severe. Mild AP is defined by AP without organ failure, local or systemic complications, and usually resolves in the first week. Moderately SAP is defined by the presence of transient organ failure that resolves in no >48 hours, or local complications or exacerbation of co-morbid disease. SAP is defined by persistent organ failure that lasts <48 hours. The presence of systemic inflammatory response syndrome is associated with increased risk for persistent organ dysfunction. Criteria to define organ failure must be pediatric- and age-based.

CONCLUSIONS

Classifying AP in pediatrics in a uniform fashion will help define outcomes and encourage the development of future studies in the field of pediatric pancreatitis.

Accuracy of contrast-enhanced ultrasound compared with conventional ultrasound in acute pancreatitis: Diagnosis and complication monitoring

Contrast-enhanced ultrasound (CEUS) has been used for diagnosing acute pancreatitis (AP), particularly severe acute pancreatitis (SAP). However, the diagnostic difference between CEUS and conventional ultrasonography (CUS) for AP and SAP has not been reported. The aim of the present study was to investigate the diagnostic accuracy of CUS and CEUS for AP. A total of 196 patients clinically diagnosed with AP were selected. All patients underwent CUS, CEUS and contrast-enhanced computed tomography (CECT) within 72 h. CECT was considered the gold standard. Pancreatic size, peripancreatic fluid collection (PPFC) and splenic vessel complications were the variables observed by CUS and CEUS. The differences in the variables among the three methods were analyzed using the χ² test and statistical analysis software. Significant differences in pancreatic size, PPFC and splenic vessel complications in AP were observed between CEUS and CUS (P<0.05). χ² test results indicated that CEUS significantly differed from CUS in terms of having a higher diagnostic accuracy for AP and SAP (P<0.05). The results indicate that CEUS is a reliable method for the diagnosis and monitoring of AP and SAP, and may be substituted for CECT.

Ultrasound: the triage tool in the emergency department: using ultrasound first

Ultrasound in the emergency department has long been recognized as a powerful screening and diagnostic tool for both physicians and radiologists. In the emergency department, since time is of the essence, it becomes a critical tool in triaging patients. Over the years, ultrasound has gained several advantages over other modalities because of its non-ionizing radiation, portability, accessibility, non-invasive method and simpler learning curve. As a result, ultrasound has become one of the most frequently used diagnostic tools in the emergency department by non-radiologists. The value of ultrasound is implemented in every acute ailment in the emergency department such as trauma, acute abdomen, acute pelvic pain, acute scrotal pain, appendicitis in children and acute deep venous thrombosis. Our objective is to discuss the benefit of using ultrasound as the primary modality for each of these diseases.

Acute pancreatitis: international classification and nomenclature

The incidence of acute pancreatitis (AP) is increasing and it is associated with a major healthcare concern. New insights in the pathophysiology, better imaging techniques, and novel treatment options for complicated AP prompted the update of the 1992 Atlanta Classification. Updated nomenclature for pancreatic collections based on imaging criteria is proposed. Adoption of the newly Revised Classification of Acute Pancreatitis 2012 by radiologists should help standardise reports and facilitate accurate conveyance of relevant findings to referring physicians involved in the care of patients with AP. This review will clarify the nomenclature of pancreatic collections in the setting of AP.

Imaging of Acute Pancreatitis

Acute pancreatitis is an acute inflammation of the pancreas. Several classification systems have been used in the past but were considered unsatisfactory. A revised Atlanta classification of acute pancreatitis was published that assessed the clinical course and severity of disease; divided acute pancreatitis into interstitial edematous pancreatitis and necrotizing pancreatitis; discerned an early phase (first week) from a late phase (after the first week); and focused on systemic inflammatory response syndrome and organ failure. This article focuses on the revised classification of acute pancreatitis, with emphasis on imaging features, particularly on newly-termed fluid collections and implications for the radiologist.

Imaging lexicon for acute pancreatitis: 2012 Atlanta Classification revisited

The original 1992 Atlanta Classification System for acute pancreatitis was revised in 2012 by the Atlanta Working Group, assisted by various national and international societies, through web-based consensus. This revised classification identifies two phases of acute pancreatitis: early and late. Acute pancreatitis can be either oedematous interstitial pancreatitis or necrotizing pancreatitis. Severity of the disease is categorized into three levels: mild, moderately severe and severe, depending upon organ failure and local/systemic complications. According to the type of pancreatitis, collections are further divided into acute peripancreatic fluid collection, pseudocyst, acute necrotic collection, and walled-off necrosis. Insight into the revised terminology is essential for accurate communication of imaging findings. In this review article, we will summarize the updated nomenclature and illustrate corresponding imaging findings using examples.

The efficacy of endoscopic papillary balloon dilation for patients with acute biliary pancreatitis

Background. No study investigated the efficacy and safety of endoscopic papillary balloon dilation (EPBD) for the treatment of acute biliary pancreatitis (ABP). Method. We retrospectively reviewed the effects of EPBD on patients with ABP from February 2003 to December 2012. The general data, findings of image studies, details of the procedure, and outcomes after EPBD were analyzed. Result. Total 183 patients (male/female: 110/73) were enrolled. The mean age was 65.9 years. Among them, 155 patients had mild pancreatitis. The meantime from admission to EPBD was 3.3 days. Cholangiogram revealed filling defects inside the common bile duct (CBD) in 149 patients. The mean dilating balloon size was 10.5 mm and mean duration of the dilating procedure was 4.3 minutes. Overall, 124 patients had gross stones retrieved from CBD. Four (2.2%) adverse events and 2 (1.1%) intraprocedure bleeding incidents but no procedure-related mortality were noted. Bilirubin and amylase levels significantly decreased after EPBD. On average, patients resumed oral intake within 1.4 days. The clinical parameters and outcomes were similar in patients with different severity of pancreatitis. Conclusion. EPBD can be effective and safe for the treatment of ABP, even in patients presenting with severe disease.

Role of N-13 ammonia PET/CT in diagnosing pancreatic necrosis in patients with acute pancreatitis as compared to contrast enhanced CT--results of a pilot study

BACKGROUND

Contrast enhanced computerized tomography (CECT) is used to determine severity of acute pancreatitis based upon the presence and extent of necrosis. However limitations do exist precluding its applicability in renal failure. Positron emission tomography (PET) imaging for cardiac perfusion shows good uptake of N-13 ammonia ((13)NH3) metabolites in pancreas owing to high perfusion.

AIM

To evaluate the role of (13)NH3 PET/CT in acute pancreatitis and compare it with CECT in diagnosing and quantifying pancreatic necrosis.

MATERIAL AND METHODS

Patients presenting within 1 week of acute pancreatitis were studied. Static PET images were acquired after intravenous injection of 370-740 MBq of (13)NH3. (13)NH3 PET/CT was followed by CECT in the absence of renal impairment. Maximum standard-uptake-value (SUVmax) of pancreas (P) and liver (L) were taken and their ratio (P/L) was estimated to determine perfusion. Areas within pancreas with no tracer uptake were considered necrotic. These patients were managed as per institutional protocol. Patients undergoing (13)NH3 PET/CT for coronary artery disease were used as controls.

RESULTS

29 patients (72% males) were studied of whom 6 had elevated serum creatinine. (13)NH3 PET/CT was done in all patients along with 9 controls while CECT was carried out after PET/CT in 23 patients. Median levels of SUVmax (P/L) in the controls, uninvolved pancreas and necrotic areas were 1.0 (0.86-1.03), 0.66 (0.50-0.92) and 0.12 (0.07-0.21) respectively (p < 0.001). Necrosis estimation was similar in 22/23 patients without renal failure while in one patient only (13)NH3 PET/CT picked up necrosis (<30%). 5/6 patients with renal failure had necrosis on (13)NH(3) PET/CT which was confirmed on surgery or subsequent CECT after improvement of renal failure.

CONCLUSION

This pilot study is the first in literature to diagnose necrosis in patients with acute pancreatitis using (13)NH3 PET/CT. With minimal additional radiation burden, it is possible to estimate the absolute tissue perfusion as well. With no adverse renal side effects, this can be an alternative to CECT in patients with renal failure giving similar information. It has good agreement with CECT with a good interobserver acceptability.

Early management of acute pancreatitis

Acute pancreatitis is the most common gastro-intestinal indication for acute hospitalization and its incidence continues to rise. In severe pancreatitis, morbidity and mortality remains high and is mainly driven by organ failure and infectious complications. Early management strategies should aim to prevent or treat organ failure and to reduce infectious complications. This review addresses the management of acute pancreatitis in the first hours to days after onset of symptoms, including fluid therapy, nutrition and endoscopic retrograde cholangiography. This review also discusses the recently revised Atlanta classification which provides new uniform terminology, thereby facilitating communication regarding severity and complications of pancreatitis.

Autoimmune pancreatitis and non-necrotizing acute pancreatitis: computed tomography pattern

OBJECTIVES

To retrospectively differentiate diffuse autoimmune pancreatitis from non-necrotizing acute pancreatitis at clinical onset with multi detector row computed tomography.

METHODS

36 Patients suffering from diffuse autoimmune pancreatitis (14) or non-necrotizing acute pancreatitis (22) were enrolled. Qualitative analysis included stranding, retroperitoneal fluid film, capsule-like rim enhancement and pleural effusion. In quantitative analysis pancreatic density was measured in all phases. The vascularization behaviour was assessed using the relative enhancement rate across all phases.

RESULTS

Pancreatic density resulted lower in non-necrotizing acute pancreatitis compared to diffuse autoimmune pancreatitis patients in pre-contrast phase and higher in pancreatic phase. Relative enhancement rate evaluation confirmed different vascularization behaviours of the two diseases. Only non-necrotizing acute pancreatitis Patients presented peripancreatic stranding and fluid in the retromesenteric interfascial plane.

CONCLUSIONS

Multi detector row computed tomography is a useful technique for differentiating diffuse autoimmune pancreatitis from non-necrotizing acute pancreatitis at clinical onset. Peripancreatic stranding and retroperitoneal fluid film, characteristic of non-necrotizing acute pancreatitis, and late-phase peripheral rim enhancement, characteristic of diffuse autoimmune pancreatitis, provide qualitative clues to the differentiation. A quantitative study of contrast enhancement patterns, considering the relative enhancement rate, can assist in the differential diagnoses of two diseases.

[Intravenous glutamine and early nasojejunal nutrition in severe acute pancreatitis -- a prospective randomized clinical study]

INTRODUCTION

Severe acute pancreatitis (SAP) is still one of the great challenges in gastro-intestinal surgery. According to recent studies, intravenously administered glutamine with total parenteral nutrition may be beneficial in the prevention of infectious complications and may reduce mortality rate. However, it has not been investigated yet, whether i.v. glutamine is able to achieve the same effect with early enteral nutrition as well.

OBJECTIVES

The objective of our prospective randomized double-blind study was to explore the effects of intravenously administered glutamine with early nasojejunal nutrition in severe acute pancreatitis.

PATIENTS AND METHODS

Forty-five patients with severe acute pancreatitis (with a Glasgow score at least 3 and/or a CRP level above 150 mg/ml on admission) were randomized into two groups. Group Glutamine (n = 24) was given 0.5 g/kg/die glutamine intravenously, while the control group (n = 21) received normal amino acid solution in the same quantity for 7 days. Nasojejunal nutrition was introduced 48 hours after admission in case of all patients, and their management was the same in every other aspect, too. The primary end-points of the study were the rate of pancreas-specific infectious complications and organ failure, and the secondary end-points were the necessity for radiological and surgical interventions, length of hospital stay and mortality rate.

RESULTS

In group Glutamine, infected acute peripancreatic fluid collections (APFC) were detected in 4 patients, 2 patients had post-necrotic pancreatic/peripancreatic fluid collections (PNPFC), 2 patients had infected pseudocysts and 2 patients had walled-off pancreatic necrosis (WOPN). Ten patients were cured by ultrasound assisted puncture or drainage successfully. No surgical intervention was necessary. In the control group, 4 patients had infected APFC, 2 patients had infected PNPFC, infected pseudocysts and infected WOPN were diagnosed in 3 cases. Radiological intervention was effective in 9 cases, but 3 patients needed surgery. Three patients died of multi-organ failure, thus the mortality rate of the control group was 14%, while the mortality rate of the Glutamine group was zero. The mean hospital stay of the Glutamine group was 10.6 days, which is significantly shorter than the mean hospital stay of the control group, which was 15.9 days (p = 0.00104).

DISCUSSION

The results of the Glutamine group are better in every end-points, however, statistically significant difference was detected in one parameter only, the length of hospital stay.

Imaging of acute pancreatitis: update of the revised Atlanta classification

Acute pancreatitis is an acute inflammatory process of the pancreatic gland with increasing incidence worldwide. Usually the clinical presentation and course are mild, with an uneventful recovery. In 10% to 20% of patients, however, local and systemic complications develop, resulting in significant morbidity and mortality. In 1992, the Atlanta symposium provided definitions for acute pancreatitis and its severity. Insights into the pathophysiology of the disease, improved diagnostic imaging, and implementation of minimally invasive techniques have led to classification updates. This article reviews the cross-sectional imaging features of acute pancreatitis and presents proposed definitions of the revised Atlanta classification.

The revised Atlanta classification of acute pancreatitis: its importance for the radiologist and its effect on treatment

An international working group has modified the Atlanta classification for acute pancreatitis to update the terminology and provide simple functional clinical and morphologic classifications. The modifications (a) address the clinical course and severity of disease, (b) divide acute pancreatitis into interstitial edematous pancreatitis and necrotizing pancreatitis, (c) distinguish an early phase (1st week) and a late phase (after the 1st week), and (d) emphasize systemic inflammatory response syndrome and multisystem organ failure. In the 1st week, only clinical parameters are important for treatment planning. After the 1st week, morphologic criteria defined on the basis of computed tomographic findings are combined with clinical parameters to help determine care. This revised classification introduces new terminology for pancreatic fluid collections. Depending on presence or absence of necrosis, acute collections in the first 4 weeks are called acute necrotic collections or acute peripancreatic fluid collections. Once an enhancing capsule develops, persistent acute peripancreatic fluid collections are referred to as pseudocysts; and acute necrotic collections, as walled-off necroses. All can be sterile or infected. Terms such as pancreatic abscess and intrapancreatic pseudocyst have been abandoned. The goal is for radiologists, gastroenterologists, surgeons, and pathologists to use the revised classifications to standardize imaging terminology to facilitate treatment planning and enable precise comparison of results among different departments and institutions.

Modern management of acute pancreatitis

There is a rising incidence of acute pancreatitis in the United States. Numerous clinical prognostic scoring systems have been developed, including the BISAP score. Vigorous fluid resuscitation remains a cornerstone of early management of acute pancreatitis. Cross-sectional imaging in the early phase of evaluation has not been associated with improvement of outcomes. There is no role for prophylactic antibiotics in early management. However, there is growing emphasis on the identification and treatment of extrapancreatic infections. Enteral nutrition in severe acute pancreatitis has reduced mortality, systemic infection, and multiorgan dysfunction compared to parenteral nutrition. Conservative management consisting of percutaneous drainage and delayed surgical intervention is now favored for local complications, such as infected necrosis. These developments have contributed to improved outcomes for patients with acute pancreatitis.

Systematic review of percutaneous catheter drainage as primary treatment for necrotizing pancreatitis

BACKGROUND

The role of percutaneous catheter drainage (PCD) in patients with (infected) necrotizing pancreatitis was evaluated.

METHODS

A systematic literature search was performed. Inclusion criteria were: consecutive cohort of patients with necrotizing pancreatitis undergoing PCD as primary treatment for peripancreatic collections; indication for PCD either (suspected) infected necrosis or symptomatic sterile pancreatic necrosis; and outcomes reported to include percentage of infected peripancreatic collections, need for additional surgical necrosectomy, complications and deaths. Exclusion criteria were: cohort of fewer than five patients; cohort included patients with chronic pancreatitis; selected subgroup of patients with acute pancreatitis studied, such as those with pseudocysts, pancreatic abscesses and/or exclusively sterile pancreatic necrosis; and cohort in which PCD was combined with another minimally invasive strategy and results for PCD alone not reported separately.

RESULTS

Eleven studies, including 384 patients, fulfilled the inclusion criteria. Only one study was a randomized controlled trial; most others were retrospective case series. Four studies reported on the presence of organ failure before PCD; this occurred in 67·2 per cent of 116 patients. Infected necrosis was proven in 271 (70·6 per cent) of 384 patients. No additional surgical necrosectomy was required after PCD in 214 (55·7 per cent) of 384 patients. Complications consisted mostly of internal and external pancreatic fistulas. The overall mortality rate was 17·4 per cent (67 of 384 patients). Nine of 11 studies reported mortality separately for patients with infected necrosis undergoing PCD; the mortality rate in this group was 15·4 per cent (27 of 175).

CONCLUSION

A considerable number of patients can be treated with PCD without the need for surgical necrosectomy.

Progress in the management of necrotizing pancreatitis

Pancreatic necrosis, a complication of severe pancreatitis, may become infected, resulting in significant morbidity and potential mortality. Infected necrosis was heretofore considered a surgical condition, and despite aggressive operative management, the mortality remained high. With a better understanding of the natural history of necrosis, established methods to diagnose infection and the increasing use of minimally invasive techniques, less aggressive therapies have been utilized with some success. The present study evaluated a step-up approach for the treatment of infected pancreatic necrosis, utilizing endoscopic and percutaneous techniques, and if ineffective, necrosectomy with a minimally invasive retroperitoneal approach. They compared this step-up approach to the standard open necrosectomy. They demonstrated that when using such an approach compared with open necrosectomy, the frequency of major complications such as organ failure, perforation, fistula or even death was significantly less than in those who received conventional open necrosectomy. Indeed, for those randomized to the step-up approach, roughly a third of the patients were successfully treated with percutaneous drainage alone. In the long-term, development of diabetes was also less frequent in those receiving less aggressive therapy. These findings, in combination with other reports, suggest that the dogma that open necrosectomy is mandatory for all patients with infected necrosis should be re-evaluated, and that less aggressive treatments as part of a multidisciplinary approach can reduce morbidity and mortality.

Acute pancreatitis: the role of imaging in diagnosis and management

Acute pancreatitis is one of the more commonly encountered aetiologies in the emergency setting and its incidence is rising. Presentations range from a mild-self limiting condition which usually responds to conservative management to one with significant morbidity and mortality in its most severe forms. While clinical criteria are necessary to make the initial diagnosis, contrast-enhanced CT is the mainstay of imaging and has a vital role in assessing the extent and evolution of the disease and its associated complications. The purpose of this article is to summarise the natural course of acute severe pancreatitis, clarify confusing nomenclature, demonstrate the morphological stages in conjunction with radiological scoring systems and illustrate the complications. We will review and illustrate the increasing and significant role interventional radiology has in the management of these patients, which are often life-saving and surgery-sparing.

Magnetic resonance imaging for acute pancreatitis

Acute pancreatitis is characterized by acute chemical injury of the pancreatic parenchyma and peripancreatic tissue. The increased frequency of death in acute pancreatitis is directly correlated with the degree and progress of pancreatic necrosis. Moreover, the occurrence of some local complications in acute pancreatitis, such as pancreatic hemorrhage, peripancreatic abscess or large pseudocyst, and pseudoaneurysm, could influence the choice of treatment for these patients. Magnetic resonance imaging (MRI) can be used to help evaluate the presence and degree of pancreatic necrosis, and is crucial for identifying complications of acute pancreatitis and predicting prognosis. The purpose of this article is to describe MRI techniques for acute pancreatitis, to review the spectrum of pancreatic and peripancreatic patterns, as well as to survey various complications secondary to acute pancreatitis on MRI. The role of MRI in the initial evaluation and staging of acute pancreatitis is emphasized.

Contrast-enhanced ultrasound in the staging of acute pancreatitis

OBJECTIVE

To determine the diagnostic value of contrast-enhanced ultrasound (CEUS) in the assessment of acute pancreatitis, with computed tomography (CT) as the reference standard.

METHODS

Fifty consecutive patients (mean age 58.4 years; range 23-86 years) with acute pancreatitis underwent prospectively both CT and ultrasonography, including CEUS, within a 24-h interval. Pancreatic vascularisation was evaluated with CEUS after injection of a second-generation US contrast-enhancing agent. Acute pancreatitis severity was graded according to the Balthazar index. The results were compared with CT severity index and clinical outcome by using Spearman's correlation coefficient.

RESULTS

A significant correlation between CT and CEUS was found for the CT severity index (r = 0.926), extent of necrosis (r = 0.893) and Balthazar grade (r = 0.884). The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for detecting severe acute pancreatitis based on CT findings (severity index greater than 3 and/or presence of necrosis) were respectively 91%, 100%, 100% and 83%. A significant correlation between CEUS severity index and clinical variables was found: Ranson score (r = 0.442), C-reactive protein (CRP) levels 48 h after admission (r = 0.385) and length of hospital stay (r = 0.362).

CONCLUSION

CEUS is comparable to CT in detecting pancreatic necrosis as well as predicting its clinical course. Therefore, when CT is contraindicated CEUS may be a valid alternative.

New diagnostic criteria of acute pancreatitis

Practical guidelines for the diagnosis of acute pancreatitis are presented so that a rapid and adequate diagnosis can be made. When acute pancreatitis is suspected in patients with acute onset of abdominal pain and tenderness mainly in the upper abdomen, the diagnosis of acute pancreatitis is made on the basis of elevated levels of pancreatic enzymes in the blood and/or urine. Furthermore, other acute abdominal diseases are ruled out if local findings associated with pancreatitis are confirmed by diagnostic imaging. According to the diagnostic criteria established in Japan, patients who present with two of the following three manifestations are diagnosed as having acute pancreatitis: characteristic upper abdominal pain, elevated levels of pancreatic enzymes, and findings of ultrasonography (US), CT or MRI suggesting acute pancreatitis. Detection of elevated levels of blood pancreatic enzymes is crucial in the diagnosis of acute pancreatitis. Measurement of blood lipase is recommended, because it is reported to be superior to all other pancreatic enzymes in terms of sensitivity and specificity. For measurements of the blood amylase level widely used in Japan, it should be cautioned that, because of its low specificity, abnormal high values are also often obtained in diseases other than pancreatitis. The cut-off level of blood pancreatic enzymes for the diagnosis of acute pancreatitis is not able to be set because of lack of sufficient evidence and consensus to date. CT study is the most appropriate procedure to confirm image findings of acute pancreatitis. Elucidation of the etiology of acute pancreatitis should be continued after a diagnosis of acute pancreatitis. In the process of the etiologic elucidation of acute pancreatitis, judgment whether it is gallstone-induced or not is most urgent and crucial for deciding treatment policy including the assessment of whether endoscopic papillary treatment should be conducted or not. The diagnosis of gallstone-induced acute pancreatitis can be made by combining detection of elevated levels of bilirubin, transamylase (ALT, AST) and ALP detected by hematological examination and the visualization of gallstones by US.

Acute pancreatitis: radiologic scores in predicting severity and outcome

Acute pancreatitis (AP) is a common inflammatory disease which can be mild and self-limiting without complications or severe with prolonged hospitalization, high morbidity, and high mortality. Different radiological scoring systems to predict severity and outcome in AP have been developed since the early 1990s. In the meantime, new insights in the pathophysiology of AP and consequently, therapeutic management of these patients have been introduced. The purpose of this review is therefore (1) to describe the current terminology and new concepts in the pathophysiology, (2) to outline the long existing and newly developed radiological scoring systems in prediction of severity and outcome with their respective advantages and limitations, and (3) to define the role of radiological prognostic scoring systems in the new environment of perception of the last decade. Risk stratification in AP requires scoring systems that can be calculated early in the course of disease which allows time for intervention. For that reason, scoring systems based on necrosis are not useful in severity prediction. The recent developed radiological scoring systems based on signs of systemic inflammatory response syndrome and organ dysfunction are promising in prediction of severity early after onset of AP.

Critical Care of the Patient with Acute Pancreatitis

Acute pancreatitis is an inflammatory process of the pancreas with variable involvement of regional tissues and remote organs. This review gives a comprehensive overview of the aetiology, pathophysiology, diagnosis and therapy of acute pancreatitis relevant to the intensivist. Recent international guidelines on the management of acute pancreatitis are summarised.

Eighty percent of acute pancreatitis episodes are related either to gallstones or to alcohol abuse. Independent of its aetiology, the pathophysiologic hallmark of acute pancreatitis is the premature activation of trypsin, which leads to massive pancreas inflammation, systemic overproduction of pro-inflammatory mediators and ultimately remote organ dysfunction. All guidelines agree that the diagnosis of acute pancreatitis should include clinical symptoms, increased serum amylase or lipase levels and/or characteristic findings on computed tomography. Endoscopic retrograde cholangiopancreatography is recommended as a causative therapy in patients with acute cholangitis or a strong suspicion of gallstones. All guidelines underline the importance of vigorous fluid resuscitation and supplemental oxygen therapy and prefer enteral over parenteral nutrition, with the majority favouring the nasojejunal route. In view of lacking scientific evidence, antibiotic prophylaxis to prevent infection of pancreatic necroses is discouraged by most guidelines. Computed tomography-guided fine needle aspiration is the technique of choice to differentiate between sterile and infected pancreas necrosis. While sterile pancreatic necrosis should be managed conservatively, infected pancreatic necrosis requires debridement and drainage supplemented by antibiotic therapy. Surgical necrosectomy is the traditional approach, but less invasive techniques (retroperitoneal or laparoscopic necrosectomy, computed tomography-guided percutaneous catheter drainage) may be equally effective.

Magnetic resonance imaging in pancreatitis

Pancreatitis can occur in acute and chronic forms. Magnetic resonance imaging (MRI) plays an important role in the early diagnosis of both conditions and complications that may arise from acute or chronic inflammation of the gland. Standard MRI techniques including T1-weighted and T2-weighted fat-suppressed imaging sequences together with contrast-enhanced imaging can both aid in the diagnosis of acute pancreatitis and demonstrate complications as pseudocysts, hemorrhage, and necrosis. Combined use of MRI and MR cholangiopancreatography can show both parenchymal findings that are associated with chronic pancreatitis including pancreatic size and signal and arterial enhancements, all of which are diminished in chronic pancreatitis. The degree of main pancreatic duct dilatation and/or the number of side branch ectasia determines the diagnosis of chronic pancreatitis and its severity. In this paper, we report the spectrum of imaging findings of acute and chronic pancreatitis on MRI and MR cholangiopancreatography.

Imaging assessment of acute pancreatitis: a review

Acute pancreatitis is one of the more commonly encountered etiologies in the emergency setting. While in the majority of cases it is a self-limiting disease which responds rapidly to conservative management, in some cases acute pancreatitis may present with a more pronounced, sometimes dramatic, clinical picture and requires immediate medical care to avoid fatal complication. In this context, imaging plays a significant role because it enables identification of the development of the disease and local/systemic complications. The purpose of this article is to offer an overview of the disease and a spectrum of imaging findings in patients with acute pancreatitis, emphasizing the role of ultrasound, computed tomography, and magnetic resonance imaging according to the appropriate clinical context and advantages and limitations of each imaging modality are examined.

Progress in evidence-based medicine for treatment of severe acute pancreatitis

Severe acute pancreatitis (SAP) is an abdominal catastrophe with a high morbidity and mortality. Up to now, no special drugs or therapeutic methods are available for SAP. Since evidence-based medicine came into being, much more clinical evidence has provided better choice of treatment for SAP. However, such evidence does not fit for all ASP patients based on its critical inclusion and exclusion criteria. It is, therefore, important to treat ASP patients by combining such evidence with clinical experiences.