Alanine transaminase rather than abdominal ultrasound alone is an important investigation to justify cholecystectomy in patients presenting with acute pancreatitis

Pathophysiology of severe gallstone pancreatitis: A new paradigm

Severe gallstone pancreatitis (GSP) refractory to maximum conservative therapy has wide clinical variations, and its pathophysiology remains controversial. This Editorial aimed to investigate the pathophysiology of severe disease based on Opie’s theories of obstruction, the common channel, and duodenal reflux and describe its types. Severe GSP might be a hybrid disease with pathology polarized between acute cholangitis with mild pancreatitis (biliary type) and necrotizing pancreatitis uncomplicated with biliary tract disease (pancreatic type), in which hepatobiliary and pancreatic lesion severity is inversely related to the presence or absence of impacted ampullary stones. Severe GSP is caused by stones that are persistently impacted at the ampulla with biliopancreatic obstruction (biliary type), and probably, stones that are either temporarily lodged at the duodenal orifice or passed into the duodenum, thereby permitting reflux of bile or possible duodenal contents into the pancreas (pancreas type). When the status of the stones and the presence or absence of impacted ampullary stones with biliopancreatic obstruction are determined, the clinical course and outcome can be predicted. Gallstones represent the main cause of acute pancreatitis globally, and clinicians are expected to encounter GSP more often. Awareness of the etiology and pathogenesis of severe disease is mandatory.

Proposal of the term “gallstone cholangiopancreatitis” to specify gallstone pancreatitis that needs urgent endoscopic retrograde cholangiopancreatography

Opie’s “pancreatic duct obstruction” and “common channel” theories are generally accepted as explanations of the mechanisms involved in gallstone acute pancreatitis (AP). Common channel elucidates the mechanism of necrotizing pancreatitis due to gallstones. For pancreatic duct obstruction, the clinical picture of most patients with ampullary stone impaction accompanied by biliopancreatic obstruction is dominated by life-threatening acute cholangitis rather than by AP, which clouds the understanding of the severity of gallstone AP. According to the revised Atlanta classification, it is difficult to consider these clinical features as indications of severe pancreatitis. Hence, the term “gallstone cholangiopancreatitis” is suggested to define severe disease complicated by acute cholangitis due to persistent ampullary stone impaction. It incorporates the terms “cholangitis” and “gallstone pancreatitis.” “Cholangitis” refers to acute cholangitis due to cholangiovenous reflux through the foci of extensive hepatocyte necrosis reflexed by marked elevation in transaminase levels caused by persistent ampullary obstruction. “Gallstone pancreatitis” refers to elevated pancreatic enzyme levels consequent to pancreatic duct obstruction. This pancreatic lesion is characterized by minimal or mild inflammation. Gallstone cholangiopancreatitis may be valuable in clinical practice for specifying gallstone AP that needs urgent endoscopic retrograde cholangiopancreatography with endoscopic sphincterotomy.

Early Prediction of Acute Biliary Pancreatitis Using Clinical and Abdominal CT Features

Background Assessment of the biliary origin of acute pancreatitis (AP) is crucial because it affects patient treatment to avoid recurrence. Although CT is systematically performed to determine severity in AP, its usefulness in assessing AP biliary origin has not been evaluated. Purpose To assess abdominal CT features associated with acute biliary pancreatitis (ABP) and to evaluate the predictive value of a combination of CT and clinical data for determining a biliary origin in a first episode of AP. Materials and Methods From December 2014 to May 2019, all consecutive patients who presented with a first episode of AP and with at least 6 months of follow-up were retrospectively reviewed. Evidence of gallstones was mandatory for a clinical diagnosis of ABP. Abdominal CT images were reviewed by two abdominal radiologists. Univariable and multivariable statistical analyses were performed, and a nomogram was constructed on the basis of the combination of clinical and CT features. This nomogram was validated in a further independent internal cohort of patients. Results A total of 271 patients (mean age ± standard deviation, 56 years ± 20; 160 men) were evaluated. Of these, 170 (63%) had ABP. At multivariable analysis, age (odds ratio [OR], 1.06; 95% CI: 1.03, 1.09; P < .001), alanine aminotransferase level (OR, 1.00; 95% CI: 1.00, 1.01; P = .009), gallbladder gallstone (OR, 15.59; 95% CI: 4.61, 68.62; P < .001), choledochal ring sign (OR, 5.73; 95% CI: 2.11, 17.05; P < .001), liver spontaneous attenuation (OR, 1.07; 95% CI: 1.04, 1.11; P < .001), and duodenal thickening (OR, 0.17; 95% CI: 0.03, 0.61; P = .01) were independently associated with ABP. The matching nomogram combining both clinical and CT features displayed an area under the curve of 0.94 (95% CI: 0.91, 0.97) in the study sample (n = 271) and 0.91 (95% CI: 0.84, 0.99) in the validation cohort (n = 51). Conclusion Abdominal CT provided useful features for diagnosis of acute biliary pancreatitis (ABP). Combining CT and clinical features in a nomogram showed good diagnostic performance for early diagnosis of ABP. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Chang in this issue.

Predictive biomarkers for acute gallstone pancreatitis in the pediatric population

BACKGROUND

Early biomarkers for diagnosis of gallstone pancreatitis (GP) in pediatrics have not been well studied. Reliably differentiating GP from other causes of acute pancreatitis (AP) would allow for early diagnosis and prompt management. We sought to assess biomarkers and clinical variables for early GP diagnosis from a prospectively-enrolled registry of pediatric patients presenting with first AP episode.

METHODS

Cross-sectional analysis of a prospective acute pancreatitis registry of children enrolled from March 2013 through October 2016 was performed. Fisher's exact test and Wilcoxon rank sum test were used to compare demographic and clinical variables between GP and non-GP groups. A multivariable logistic regression model was derived, and receiver operating characteristic (ROC) curve was built using stepwise selection.

RESULTS

114 subjects were enrolled (21 with GP, 93 as non-GP). Median was statistically higher for GP patients in lipase values X upper limit of normal (ULN) on admission, weight percentile for age, alanine aminotransferase, aspartate aminotransferase, and gamma-glutamyl transferase. By multivariable analysis, significant predictors were ALT and Lipase xULN. A model built using these two variables for prediction of GP identified an AUROC of 0.85. At a predictive probability of 0.35, the model had an 80% sensitivity, 93% specificity, 76% positive predictive value and 95% negative predictive value.

CONCLUSIONS

We have developed a model for predicting GP in children that could help guide clinical management of AP patients. Future studies are needed to validate use of laboratory findings and clinical variables in evaluation of gallstone etiology in pediatric AP patients.

IL-8 gene polymorphism in acute biliary and non biliary pancreatitis: probable cause of high level parameters?

Backgrounds/Aims

Inflammatory mediators of the innate immune response play fundamental roles in the pathogenesis of acute pancreatitis. The correlation between interleukin-8 (IL-8) gene polymorphism with types of acute pancreatitis and severity of pancreatitis, was evaluated in this study.

Methods

According to the diagnostic criteria, 176 patients with acute pancreatitis were grouped into biliary (n=83) and nonbiliary pancreatitis (n=93). Healthy blood donors (n=100) served as controls. Serum alanine transaminase, aspartate transaminase, total and direct bilirubin, amylase, lypase, white blood cell count and c-reactive protein levels were evaluated to correlate with IL-8 rs4073 (-251T/A) polymorphism, which was analyzed using a real-time polymerase chain reaction method with melting point analysis.

Results

The IL-8 AA genotype was detected with a significantly higher frequency among the patients with acute biliary pancreatitis having higher alanine transaminase levels than the median range. Homozygote alleles were significantly higher among patients with acute biliary pancreatitis having amylase levels higher than the median range.

Conclusions

Determination of the frequency of IL-8 polymorphism in acute pancreatitis is informative and provides further evidence concerning the role of IL-8 in laboratory tests.

Repeated transabdominal ultrasonography is a simple and accurate strategy to diagnose a biliary etiology of acute pancreatitis

OBJECTIVES

Transabdominal ultrasonography (US) usually reveals diagnosis of biliary acute pancreatitis (AP). Guidelines suggest repeating US in AP patients without cause at first examination. This approach has been poorly investigated, as well as the accuracy of repeated US as compared with that of magnetic resonance cholangiopancreatography. This study aims at evaluating the diagnostic accuracy of repeated US for biliary AP.

METHODS

The accuracy of each test for diagnosis of biliary AP was evaluated according to the final diagnosis. Comparison between tests was obtained by examining the areas under the receiver operating characteristic curves.

RESULTS

Among 155 patients, the etiology was biliary in 52% and alcoholic in 20%. The accuracy of the first US alone and of the 2 combined examinations for a biliary etiology were 66% and 83%, respectively. Comparison of receiver operating characteristic curves showed a better performance of repeated US (difference between areas under the curve, 0.135; 95% confidence interval, 0.02-0.24; P = 0.021). Magnetic resonance cholangiopancreatography had high specificity (93%) but low sensitivity (62%), with 76% accuracy. The accuracy of the combination of the 2 US examinations and of elevated alanine transferase was 87%.

CONCLUSIONS

Repeated US is effective for biliary AP diagnosis. The combination of repeated US examinations and biochemical tests seems an effective approach, whereas magnetic resonance cholangiopancreatography might be restricted to selected cases.