Pancreatic function testing: Here to stay for the 21st century

Serum Trypsin Is a Reliable Biomarker of Pancreas Function

ABSTRACT

Pancreatic diseases pose significant diagnostic and therapeutic challenges necessitating robust biomarkers for accurate diagnosis, management, and monitoring of pancreas function.Pancreas function can be measured with direct (invasive) and indirect tests. However, neither approach allows for continuous disease monitoring to identify disease progression or therapeutic response. We demonstrate literature evidence suggesting that trypsin, an important pancreatic digestive enzyme, holds promise as a continuous biomarker. On one hand, assessment of trypsin concentration in the serum sensitively and specifically detects pancreas inflammation; whereas on the other hand, declining trypsin levels in serum show good correlation with direct pancreatic function tests to identify exocrine pancreatic insufficiency. With this comprehensive review, we aimed to evaluate the existing evidence on the utility of trypsin as a continuous biomarker, spanning from acute to chronic pancreatitis and pancreas function, highlighting its potential in monitoring disease evolution on an individual patient level.

Preanalytical and analytical factors affecting elastase quantitation in stool

Exocrine pancreatic insufficiency (EPI) is a condition caused by a deficiency of exocrine pancreatic enzymes, resulting in malabsorption of nutrients. Clinical manifestations of EPI may include steatorrhea, weight loss, diarrhea, and abdominal pain. Although direct testing is the most sensitive and specific for EPI, these tests are invasive, time consuming, expensive, and not well standardized. Fecal elastase (FE-1) has been shown to be an indirect marker of the exocrine secretory capacity of the pancreas and has become the most commonly employed indirect test for diagnosis of EPI. Measurement of fecal elastase consists of two main phases, a preanalytical phase and analytical phase. The preanalytical phase involves stool collection, storage and handling. The second phase is the analytical phase, which includes the actual assay processes and products used to produce a result. For FE-1 this includes sample extraction and measurement on an immunoassay. Each step in the process can influence the result and contribute to heterogeneity in FE-1 measurement, potentially impacting clinical diagnosis and management. Thus, this paper provides an overview of the preanalytical and analytical factors that can affect measurement and interpretation of FE-1 results.

Pancreas and pancreatitis: Exocrine pancreatic insufficiency

Exocrine pancreatic insufficiency (EPI) is highly prevalent among individuals with cystic fibrosis (CF). Individuals diagnosed with EPI are often labeled as having "pancreas insufficient cystic fibrosis (PI-CF)" while those with normal exocrine function are labeled as "pancreas sufficient CF (PS-CF)." This diagnosis of EPI relies on clinical and laboratory features and management involves consumption of pancreas enzyme replacement therapy. In this review, we discuss the nuances of diagnosis and management of EPI in CF. We also present emerging evidence on the effects of CFTR modulating agents on the management of EPI, and speculate that these medications may lead to greater heterogeneity in management of EPI in CF moving forward.

Exocrine pancreatic insufficiency and pancreatic exocrine replacement therapy in clinical practice

Exocrine pancreatic insufficiency (EPI) is a complex condition that disrupts normal digestion and absorption. Patients with EPI may suffer from mild to debilitating malabsorption with a constellation of symptoms that can have a significant effect on quality of life and nutrition status. Pancreatic enzyme replacement therapy (PERT) is effective and safe to treat EPI and is the standard of care for this condition. A wide variety and various forms of these products exist, as well as numerous guidelines and recommendations. Obtaining PERT for patients can oftentimes be cost prohibitive. Determining the presence and extent of EPI can be challenging and patient specific, making it difficult for practitioners. This narrative review will explore these issues, as well as several disease states potentially affected by EPI, and review current management strategies.

Highly Sensitive Detection of Chymotrypsin Based on Metal Organic Frameworks with Peptides Sensors

In this study, peptides and composite nanomaterials based on copper nanoclusters (CuNCs) were used to detect chymotrypsin. The peptide was a chymotrypsin-specific cleavage peptide. The amino end of the peptide was covalently bound to CuNCs. The sulfhydryl group at the other end of the peptide can covalently combine with the composite nanomaterials. The fluorescence was quenched by fluorescence resonance energy transfer. The specific site of the peptide was cleaved by chymotrypsin. Therefore, the CuNCs were far away from the surface of the composite nanomaterials, and the intensity of fluorescence was restored. The limit of detection (LOD) using Porous Coordination Network (PCN)@graphene oxide (GO) @ gold nanoparticle (AuNP) sensor was lower than that of using PCN@AuNPs. The LOD based on PCN@GO@AuNPs was reduced from 9.57 pg mL^-1 to 3.91 pg mL^-1. This method was also used in a real sample. Therefore, it is a promising method in the biomedical field.

Type 1 Diabetes: A Disorder of the Exocrine and Endocrine Pancreas

Type 1 diabetes has historically been described as an endocrine (β-cell) specific autoimmune disease. However, a substantial reduction (20-50%) in pancreas organ size and subclinical to symptomatic exocrine pancreatic insufficiency are present at diagnosis and may begin even prior to the development of islet autoimmunity. The mechanisms of exocrine loss in type 1 diabetes are not well understood, but leading hypotheses include developmental defects, β-cell loss resulting in exocrine atrophy, or autoimmune or inflammatory destruction of exocrine cells. Inflammatory changes including acute and chronic pancreatitis, exocrine T cell infiltration and classical complement activation, and serum exocrine autoantibodies within type 1 diabetes individuals suggest that an autoimmune or inflammatory process may contribute to exocrine pancreatic dysfunction. Exocrine pancreas atrophy primarily occurs prior to the onset of clinical disease. Indeed, recent work implicates exocrine-specific alterations in gene and protein expression as key in type 1 diabetes development. Measures of exocrine size and function could be useful additions in the prediction of disease onset and in identifying potential therapeutic responders to disease therapies, however, this is an underdeveloped area of research. Additionally, exocrine pancreatic insufficiency is underdiagnosed in individuals with type 1 diabetes and individualized treatment protocols are lacking. Much work remains to be done in this area, but we can definitively say that type 1 diabetes is a disorder of both the exocrine and endocrine pancreas likely from the start.

Fat-Soluble Vitamin Deficiencies and Disruption of the Immune System in Pancreatic Cancer: A Vicious Cycle

ABSTRACT

Pancreatic ductal adenocarcinoma (PDAC) is currently an increasing contributor to cancer-related mortality. Despite advances in cancer treatment, PDAC survival rates have remained roughly unchanged over the years. Specifically, late diagnosis and insensitivity to currently available therapeutic regimens have been identified as the main causes for its poor survival. Pancreatic exocrine insufficiency (PEI) is a typical complication associated with PDAC diagnosis and pancreatic surgery. Pancreatic exocrine insufficiency, a major contributor to maldigestion in PDAC, is often not treated because it remains undetected because of lack of overt signs and symptoms. In this review, we will focus on the major consequences of PEI, including the inadequacy of lipase excretion, which results in deficiency of fat-soluble vitamins. Because PDAC is known for its immune-high jacking mechanisms, we describe key features in which deficiencies of fat-soluble vitamins may contribute to the aggressive biological behavior and immune evasion in PDAC. Because PEI has been shown to worsen survival rates in patients with PDAC, detecting PEI and the related fat-soluble vitamin deficits at the time of PDAC diagnosis is critical. Moreover, timely supplementation of pancreatic enzymes and fat-soluble vitamins may improve outcomes for PDAC patients.

How Are Imaging Findings Associated with Exocrine Insufficiency in Idiopathic Chronic Pancreatitis?

Aim  The aim is to study the association between imaging findings in chronic pancreatitis and fecal elastase 1 (FE1) in patients with idiopathic chronic pancreatitis (ICP).

Methods  In this retrospective study on a prospectively maintained database of patients with ICP, a radiologist blinded to clinical and laboratory findings reviewed CT and/or MRI. Findings were documented according to recommendations of the Consortium for the Study of Chronic Pancreatitis, Diabetes, and Pancreatic Cancer, October 2018. Low FE1 (<100 μg elastase/g) was considered diagnostic of pancreatic exocrine insufficiency (PEI). Association between imaging findings and FE1 was studied.

Results  In total, 70 patients (M: F = 37:33) with ICP with mean age of 24.2 (SD 6.5) years, range 10 to 37 years and mean disease duration of 5.6 (SD 4.6) years, range 0 to 20 years were included. Mean FE level was 82.5 (SD 120.1), range 5 to 501 μg elastase/g. Mean main pancreatic duct (MPD) caliber was 7 (SD 4) mm, range 3 to 21 mm and mean pancreatic parenchymal thickness (PPT) was 13.7 (SD 5.5) mm, range 5 to 27 mm. There was a significant association between FE1 and MPD size, PPT, type of pancreatic calcification; presence of intraductal stones, side branch dilatation on magnetic resonance cholangiopancreatography and extent of pancreatic involvement ( p <0.05). In total, 79%, 86%, and 78% with moderate to severe MPD dilatation, pancreatic atrophy, and side branch dilatation had low FE1, respectively. But nearly half of those with no or mild structural abnormality on imaging had low FE1.

Conclusion  Significant association between FE1 and specific imaging findings demonstrates its potential as a marker of exocrine insufficiency and disease severity in chronic pancreatitis. But imaging and FE1 are complementary rather than supplementary.

Minimal Change Patients Versus Obvious Chronic Pancreatitis: A Comparison of Classical Secretin Stimulation Testing Results

OBJECTIVES

The objective was to assess if the peak bicarbonate level during secretin stimulation testing (SST) differs between patients with minimal change (or small duct) chronic pancreatitis (CP) versus those with obvious CP (or large duct) versus those without CP.

METHODS

Two hundred nineteen patient records at the University of Florida who had been referred for SST were analyzed for peak bicarbonate, total volume of juice collected, age, sex, and clinical presentation.

RESULTS

Fifty-one patients with minimal change CP were identified. Thirty-three patients were felt to have advanced CP, and 135 patients did not have CP by clinical criteria. The peak bicarbonate and total volume of pancreatic juice collected was significantly different (P < 0.001) between all 3 groups by multiple comparison testing. The peak bicarbonate of advanced CP and minimal change groups was less than controls (P < 0.001). There was a significant difference (P < 0.05) on direct testing between peak bicarbonate in advanced CP and minimal change CP.

CONCLUSIONS

The peak bicarbonate and volume measured during SST differs among patients with minimal change CP, advanced CP and in disease controls. These results could be useful in diagnosing minimal change/early CP.

Assessment of exocrine pancreatic function in children and adolescents with direct and indirect testing

The exocrine pancreas plays an important role in digestion. Understanding of the physiology and regulation of exocrine function provides insight into disease processes and basis of functional testing. Specifically, exocrine pancreatic insufficiency (EPI) can cause maldigestion and thus a proper assessment of exocrine pancreatic function is important. There are indirect and direct methods for evaluating pancreatic function. Indirect methods are varied and include stool, serum, urine, and breath tests. Fecal elastase is a commonly used indirect test today. Direct methods involve stimulated release of pancreatic fluid that is collected from the duodenum and analyzed for enzyme activity. The most used direct test today is the endoscopic pancreatic function test. Indirect pancreatic function testing is limited in identifying cases of mild to moderate EPI, and as such in these cases, direct testing has higher sensitivity and specificity in diagnosing EPI. This review provides a comprehensive guide to indirect and direct pancreatic function tests as well as an in-depth look at exocrine pancreatic function including anatomy, physiology, and regulatory mechanisms.

Current advances in the management of chronic pancreatitis

Chronic pancreatitis is characterized by irreversible destruction of pancreatic parenchyma and its ductal system resulting from longstanding inflammation, leading to fibrosis and scarring due to genetic, environmental, and other risk factors. The diagnosis of chronic pancreatitis is made based on a combination of clinical features and characteristic findings on computed tomography or magnetic resonance imaging. Abdominal pain is the most common symptom of chronic pancreatitis. The main aim of treatment is to relieve symptoms, prevent disease progression, and manage complications related to chronic pancreatitis. Patients who do not respond to medical treatment or not a candidate for surgical treatment are usually managed with endoscopic therapies. Endoscopic therapies help with symptoms such as abdominal pain and jaundice by decompression of pancreatic and biliary ducts. This review summarizes the risk factors, pathophysiology, diagnostic evaluation, endoscopic treatment of chronic pancreatitis, and complications. We have also reviewed recent advances in endoscopic retrograde cholangiopancreatography and endoscopic ultrasound-guided therapies for pancreatic duct obstruction due to stones, strictures, pancreatic divisum, and biliary strictures.

Design of 99mTc-labeled zinc-chelating imaging probe for SPECT imaging of the pancreas

Early and sensitive diagnosis of pancreatic diseases is a contemporary clinical challenge. Zinc level in pancreatic tissue and its secretion in pancreatic juice has long been considered a surrogate marker of pancreatic function. The objective of this study was to design a Zn-chelating imaging probe (ZCIP) which could be labeled with ^99mTc radionuclide for imaging of pancreas using single photon emission tomography (SPECT). We synthesized ZCIP as a bifunctional chelate consisting of diethylene triamine pentaacetic acid for ^99mTc-chelation at one end and bispicolylethylamine for Zn-complexation at the other end. ZCIP was labeled with ^99mTc by standard Sn²⁺-based reduction method. The ^99mTc-labeled ZCIP was studied in normal mice (0.3 mCi) for SPECT imaging. We found that ZCIP consistently labeled with ^99mTc radionuclide with over 95% efficiency. Addition of ZCIP altered the spectrum of standard dithizone-Zn complex, indicating its ability to chelate Zn. SPECT data demonstrated the ability of ^99mTc-ZCIP to image pancreas with high sensitivity in a non-invasive manner; liver and spleen were the other major organs of ^99mTc-ZCIP uptake. Based on these results, we conclude that ^99mTc-ZCIP presents as a novel radiotracer for pancreas imaging for diagnosis of diseases such as pancreatitis.

Exocrine pancreas functions in children with type 1 diabetes mellitus

BACKGROUND AND STUDY AIM

We evaluated exocrine pancreas functions using a noninvasive indicator in a case-control study conducted on children and adolescents diagnosed with type 1 diabetes mellitus.

PATIENTS AND METHODS

Sixty-seven patients who participated in a summer camp were enrolled in this study. Nineteen healthy children in the same age group were assigned to the control group. Fecal pancreatic elastase was assayed using the enzyme-linked immunosorbent assay technique. Values higher than 200 µg/g were considered an indication of sufficient exocrine pancreatic functioning, values between 100 µg/g and 200 µg/g were considered mild exocrine pancreatic insufficiency, and values below 100 µg/g were considered severe exocrine pancreatic insufficiency.

RESULTS

The mean concentration of fecal elastase was 158.38 ± 59.67 µg/g. The patients were assigned to three groups according to these values. Thirteen patients (22%) had sufficient fecal elastase levels, whereas 36 patients (62%) had mildly insufficient levels, and nine patients (16%) had severely insufficient fecal elastase concentrations. The levels of fecal elastase, amylase, lipase, and zinc were significantly different between the patients and controls (p < 0.001). Only the duration of diabetes was significantly different between patients with different severities of exocrine pancreatic insufficiency (p = 0.037). Additionally, the group with severe pancreatic insufficiency had more frequent hypoglycemic attacks.

CONCLUSION

Exocrine pancreatic insufficiency may develop in children with diabetes, and hypoglycemia attacks are observed more frequently depending on the severity of pancreatic insufficiency.

Pancreatic Enzyme Replacement Therapy in Patients Undergoing First-Line Gemcitabine Plus nab-paclitaxel for Advanced Pancreatic Adenocarcinoma

BACKGROUND

The clinical consequences of pancreatic exocrine insufficiency and its treatment in advanced pancreatic ductal adenocarcinoma (PDAC) are poorly investigated. This retrospective study aims at investigating the pancreatic enzyme replacement therapy (PERT) use and its impact on survival and maldigestion-related symptoms in advanced PDAC patients undergoing chemotherapy.

METHODS

A retrospective analysis was conducted on advanced PDAC patients, treated with first-line gemcitabine plus nab-paclitaxel at two academic institutions (March 2015-October 2018). Data were correlated with overall survival (OS) using Cox regression model. Kaplan-Meier curves were compared using Log-Rank test.

RESULTS

Data from 110 patients were gathered. PERT was administered in 55 patients (50%). No significant differences in baseline characteristics with those who did not receive PERT were found. Median OS for the entire group was 12 months (95% CI 9-15). At multivariate analysis, previous surgical resection of the primary tumor, (HR 2.67, p=0.11), weight gain after 3 months (HR 1.68, p=0.07) and PERT (HR 2.85, p ≤ 0.001) were independent predictors of OS. Patients who received PERT reported an improvement of maldigestion-related symptoms at 3 months more frequently than patients who did not (85.2% vs 14.8%, p ≤ 0.0001).

CONCLUSION

PERT is associated with significantly prolonged survival and maldigestion-related symptoms alleviation in advanced PDAC patients.

Imaging of inflammatory disease of the pancreas

Increasingly acute and chronic pancreatitis (AP and CP) are considered a continuum of a single entity. Nonetheless, if, after flare-up, the pancreas shows no residual inflammation, it is classified as AP. CP is characterised by a long cycle of worsening and waning glandular inflammation without the pancreas ever returning to its baseline structure or function. According to the International Consensus Guidelines on Early Chronic Pancreatitis, pancreatic inflammation must last at least 6 months before it can be labelled CP. The distinction is important because, unlike AP, CP can destroy endocrine and exocrine pancreatic function, emphasising the importance of early diagnosis. As typical AP can be diagnosed by clinical symptoms plus laboratory tests, imaging is usually reserved for those with recurrent, complicated or CP. Imaging typically starts with ultrasound and more frequently with contrast-enhanced computed tomography (CECT). MRI and/or MR cholangiopancreatography can be used as a problem-solving tool to confirm indirect signs of pancreatic mass, differentiate between solid and cystic lesions, and to exclude pancreatic duct anomalies, as may occur with recurrent AP, or to visualise early signs of CP. MR cholangiopancreatography has replaced diagnostic endoscopic retrograde cholangiopancreatography (ERCP). However, ERCP, and/or endoscopic ultrasound (EUS) remain necessary for transpapillary biliary or pancreatic duct stenting and transgastric cystic fluid drainage or pancreatic tissue sampling, respectively. Finally, positron emission tomography-MRI or positron emission tomography-CT are usually reserved for complicated cases and/or to search for extra pancreatic systemic manifestations. In this article, we discuss a broad spectrum of inflammatory pancreatic disorders and the utility of various modalities in diagnosing acute and chronic pancreatitis.

Relationship between Pancreas Exocrine Insufficiency and Cardiac Autonomic Neuropathy in Patients with Type 2 Diabetes Mellitus

BACKGROUND

The exocrine function of the pancreas is controlled by the autonomic nervous system (ANS), and autonomic neuropathy is a common and serious complication of diabetes. There are many factors contributing to the development of autonomic neuropathy in diabetic patients. Cardiovascular tests have been developed to evaluate the function of the ANS. This study investigated the relationship between cardiovascular autonomic neuropathy (CAN) and pancreas exocrine insufficiency (PEI) in diabetic patients.

METHODS

This study evaluated 110 individuals with type 2 diabetes mellitus (T2DM) and 40 healthy volunteers. Autonomous neuropathy tests were utilized to diagnose patients, and Ewing and Clarke's criteria were employed to assess the severity of autonomous dysfunction. Stool samples were also collected from patients to measure fecal elastase-1 (FE-1).

RESULTS

A 65.5% incidence of PEI was observed in DM patients. There was no significant correlation among the duration of disease, C-peptide, HbA1c, and PEI, respectively (P = .782, P = .521, P = .580). However, a significant difference between DM patients and controls in terms of cardiac dysautonomia (P = .001) was seen. Moreover, a statistically significant correlation between the degree of cardiac dysautonomia and FE-1 level was observed within the patient group (P =.001).

CONCLUSION

It is possible that the disruption of exocrine hormone secretion in the pancreas due to the impairment of enteropancreatic reflexes is secondary to diabetic autonomic neuropathy and resulting in PEI. This study also showed that autonomic neuropathy might develop and cause PEI in diabetic patients without known added confounding factors.

Malnutrition after pancreatic enzyme replacement therapy in chronic pancreatitis: Risk factors in real world practice

BACKGROUND

RCTs that have shown improvement in coefficient of fat absorption with pancreatic enzyme replacement therapy (PERT) have seldom evaluated the impact on overall nutritional status.

OBJECTIVE

In this study we evaluated factors responsible for persistence of malnutrition after PERT.

METHODS

In this cross-sectional observational study, patients were enrolled based on predefined enrolment criteria. Patients were divided into those taking PERT regularly (Group A), irregularly (Group B) and not taking (Group C) for at least 3 months. Comprehensive evaluation of anthropometric measurements, nutritional assessment and dietary intake was performed. Malnutrition was measured using the Subjective Global Assessment (SGA) tool. Relationship between PERT status, dietary intake and nutritional status were evaluated using standard statistical methods. Logistic regression was performed to identify factors associated with persistence of malnutrition after PERT.

RESULTS

377 patients with CP and 50 controls were included. 95 (25.2%) patients with CP were in Group A, 106 (28.1%) in Group B and 176 (46.7%) in Group C. 130 (34.5%) patients were malnourished, of which 76 (58.5%) were continuing PERT. There were no differences in clinical and biochemical nutritional markers between Groups A, B, and C. Calorie deficit and daily intake of calorie, protein, carbohydrates and fats were not different between those with and without PERT, but was significantly less in those with malnutrition. Logistic regression demonstrated inadequate dietary intake as independent risk factor for persistence of malnutrition.

CONCLUSION

Even though PERT is effective in PEI, comprehensive nutritional assessment, personalized nutritional counselling and therapy along with PERT is mandatory.

Vascular complications of chronic pancreatitis: A tertiary center experience

INTRODUCTION

Vascular complications such as venous thrombosis (VT) and pseudoaneurysm are not uncommon in patients with chronic pancreatitis (CP). The aim of this study to was to evaluate the prevalence and risk factors for vascular complications in patients with CP.

METHODS

A retrospective analysis of a prospectively maintained database of patients with CP presenting from January 2002 to August 2019 was performed. Venous thrombosis and pseudoaneurysm were identified using radiological imaging, and their risk factors were identified using multivariate Cox-proportional hazards.

RESULTS

Of 1363 patients with CP, 166 (12.2%) had vascular complications. Isolated VT was present in 132, pseudoaneurysm in 17, and both in 17 patients. They were more commonly seen in males and alcoholic CP (ACP), and less commonly in patients with pancreatic atrophy and calcification. It involved the vessels in the closest proximity to the pancreas, VT most commonly involving the splenic vein whereas pseudoaneurysm most commonly involved the splenic artery. Alcoholic CP [odds ratio (OR) 2.1, p = 0.002], pseudocyst (OR 4.6, p < 0.001) and inflammatory head mass (OR 3.1, p = 0.006) were independent risk factors for VT, whereas ACP (OR 3.49, p = 0.006) and pseudocyst (OR 3.2, p = 0.002) were independent risk factors for pseudoaneurysm. Gastrointestinal bleed occurred in 3.5% patients, and more commonly in patients with pseudoaneurysm than VT (64.7% vs 15.9%), and in patients with ACP in comparison to other etiologies (p < 0.001).

CONCLUSION

Vascular complications are a common complication of CP, VT being more frequent than pseudoaneurysm. Pseudocyst and ACP are independent risk factors for the development of vascular complications.

Differential Diagnosis and Management of Diarrhea in Patients with Neuroendocrine Tumors

Diarrhea is a recurrent symptom in patients with neuroendocrine tumors (NETs) and can represent different etiologies; thus, differential diagnosis is challenging. This paper distinguishes the different causes of chronic diarrhea in patients with gastroenteropancreatic NETs, with the aim to identify the most appropriate therapeutic approach. Underlying causes of diarrhea can be multifactorial, including not only diarrhea that is related to specific hormonal hypersecretory syndromes, but also diarrhea that is secondary to the following: extensive surgery which can cause pancreatic exocrine insufficiency or short bowel syndrome, treatment with somatostatin analogs or other antineoplastic agents, and bile acid malabsorption. After initial management of diarrhea with general treatments (dietary modification, use of antidiarrheals), a proper differential diagnosis is necessary to treat patients with specific etiology-driven therapeutic approaches, such as somatostatin analogs, pancreatic enzyme replacement therapy, and tryptophan hydroxylase inhibitors. In conclusion, NETs should be considered in the differential diagnosis of patients suffering from chronic diarrhea, after the exclusion of more common etiologies. Furthermore, physicians should keep in mind that several different etiologies might be responsible for diarrhea occurrence in NET patients. A prompt diagnosis of the actual cause of diarrhea is necessary to guide the treatment and a multidisciplinary approach is mandatory.

Report on the Short Endoscopic Exocrine Pancreatic Function Test in Children and Young Adults

OBJECTIVES

Endoscopic pancreatic function test (ePFT) has been in use for exocrine function testing since the 1990s. In patients, short ePFT assesses acinar function, unlike the longer version for ductal function in adults. The present study summarizes characteristics of 1913 short ePFTs (S-ePFT) performed at 2 centers since 2001.

METHODS

The main indications in patients presenting at ages infancy to 24.3 years, for the S-ePFT were failure to thrive, weight loss, diarrhea, and abdominal pain with bloating. Secretin was administered as bolus, and 4 aliquots of fluid were collected between 4 and 10 minutes after administration. Amylase, lipase, trypsin, and chymotrypsin activities were measured in the laboratory.

RESULTS

The pH of consecutive samples increased by 0.3 to 0.7. Overall, 36.7% had abnormal S-ePFT with selective amylase deficiency (9.5%) and generalized enzyme deficiency (8.9%) being the most frequent. Retest reproducibility, repeatability, and clinical validity were high. By adding S-ePFT to endoscopy for the suspicion of malabsorption, the abnormal findings increased by 36.9%.

CONCLUSIONS

Short ePFT assesses pancreatic acinar function in a reliable and clinically meaningful way in patients. Diagnostic yield of endoscopy increased substantially albeit with increased sedation time. By S-ePFT ductal function, cytokines and proteomics can also be assessed.

Exocrine Pancreatic Insufficiency in Type 1 and Type 2 Diabetes

PURPOSE OF REVIEW

Type 1 and type 2 diabetes are often accompanied by mostly mild forms of exocrine pancreatic insufficiency. Despite high prevalence, little is known about the clinical consequences of exocrine pancreatic insufficiency and its optimal (nutritional) treatment. Even less is known if and to what extent exocrine pancreas insufficiency also affects glycemic control in diabetes. This article aims for summarizing current clinical knowledge on screening, diagnosis, and treatment and gives an overview on the pathophysiology of exocrine pancreatic insufficiency in diabetes.

RECENT FINDINGS

Recent studies reveal novel insights into the close interaction of acinar, ductal, and endocrine cells and the gut-pancreas axis. Exocrine pancreatic insufficiency is a clinically relevant, frequent but poorly understood disorder in both type 1 and type 2 diabetes.

Understanding pancreatic exocrine insufficiency and replacement therapy in pancreatic cancer

Pancreatic exocrine insufficiency (PEI) is highly prevalent in patients with pancreatic cancer, and has substantial implications for quality of life and survival. Post resection, PEI is associated with increased post-operative complications, longer hospital stays and higher costs. Treatment with pancreatic enzyme replacement therapy (PERT) improves quality of life and confers significant survival advantages. Despite this many patients with pancreatic cancer do not currently receive PERT. The nutritional consequences of PEI are extensive and even more relevant in the elderly owing to age related gastrointestinal tract and pancreatic changes that predispose to malnutrition.

Pancreatic Enzyme Replacement Therapy in Pancreatic Cancer

Pancreatic cancer is an aggressive malignancy and the seventh leading cause of global cancer deaths in industrialised countries. More than 80% of patients suffer from significant weight loss at diagnosis and over time tend to develop severe cachexia. A major cause of weight loss is malnutrition. Patients may experience pancreatic exocrine insufficiency (PEI) before diagnosis, during nonsurgical treatment, and/or following surgery. PEI is difficult to diagnose because testing is cumbersome. Consequently, PEI is often detected clinically, especially in non-specialised centres, and treated empirically. In this position paper, we review the current literature on nutritional support and pancreatic enzyme replacement therapy (PERT) in patients with operable and non-operable pancreatic cancer. To increase awareness on the importance of PERT in pancreatic patients, we provide recommendations based on literature evidence, and when data were lacking, based on our own clinical experience.

Perspective on chymotrypsin detection

Chymotrypsin is one of the most extensively known proteases participating in the pathogenesis of various diseases, which can be used in drug discovery and clinical diagnosis.

Clube Português do Pâncreas Recommendations for Chronic Pancreatitis: Etiology, Natural History, and Diagnosis (Part I)

Chronic pancreatitis (CP) is a heterogeneous disease, with different causes and often a long delay between onset and full classic presentation. Clinical presentation depends on the stage of the disease. In earlier stages, recurrent episodes of acute pancreatitis are the major signs dominating clinical presentation. As the inflammatory process goes on, less acute episodes occur, and pain adopts different aspects or may even disappear. After 10-15 years from onset, functional insufficiency occurs. Then, a classic presentation with pain and pancreatic exocrine and endocrine insufficiency appears. Diagnosis remains challenging in the early stages of the disease, as its initial presentation is usually ill-defined and overlaps with other digestive disorders. Computed tomography and magnetic resonance cholangiopancreatography should be the first choice in patients with suspected CP. If the results are normal or equivocal but still there is a high suspicion of CP, the next option should be endoscopic ultrasound. Endoscopic retrograde cholangiopancreatography is mainly a therapeutic technique, and for the diagnostic purpose should only be used when all other imaging modalities and pancreatic function tests have been exhausted. Indirect tests are used to quantify the degree of insufficiency in already-established late CP. Recommendations on CP were developed by Clube Português do Pâncreas (CPP), based on literature review to answer predefined topics, subsequently discussed and approved by all members of CPP. Recommendations are separated in two parts: "chronic pancreatitis etiology, natural history, and diagnosis," and "chronic pancreatitis medical, endoscopic, and surgical treatment." This abstract pertains to part I.

Assessment of Exocrine Pancreatic Function During Endoscopy in Children

This article will review briefly the physiology of pancreatic enzyme secretion and the role of stimulated endoscopic testing for assessing exocrine pancreatic function. Published studies in both the pediatric and adult literature are reviewed. The technique and utility of endoscopic pancreatic function testing as the method of choice in the differential diagnosis of pancreatic disorders in childhood is described. Finally, emerging, clinically useful markers that can be measured in the pancreatic fluid will be described.

Exocrine pancreatic insufficiency: prevalence, diagnosis, and management

Exocrine pancreatic insufficiency (EPI) is a condition caused by reduced or inappropriate secretion or activity of pancreatic juice and its digestive enzymes, pancreatic lipase in particular. EPI can result in clinical manifestation and biochemical alterations causing reduced quality of life and life-threating complications. EPI is common in pancreatic disorders, where it should be suspected and actively investigated, and in many extrapancreatic conditions. There are various tests available to diagnose EPI, with indirect, noninvasive ones, such as concentration of fecal elastase being more commonly employed. Administration of pancreatic enzymes replacement therapy remains the mainstay of EPI treatment. The present review article will discuss current evidence regarding the prevalence of EPI, the available tests to diagnose it and its treatment.

Comparing acid steatocrit and faecal elastase estimations for use in M-ANNHEIM staging for pancreatitis

AIM

To compare two tests for exocrine pancreatic function (EPF) for use in M-ANNHEIM staging for pancreatitis.

METHODS

One hundred and ninety four consecutive patients with acute pancreatitis (AP; n = 13), recurrent acute pancreatitis (RAP; n = 65) and chronic pancreatitis (CP; n = 116) were enrolled. EPF was assessed by faecal elastase-1 (FE-1) estimation and stool fat excretion by the acid steatocrit method. Patients were classified as per M-ANNHEIM stages separately based on the results of the two tests for comparison. Independent Student's t-test, χ² test, Kruskal-Wallis test, Mann-Whitney U test and McNemar's test were used as appropriate.

RESULTS

Sixty-one (52.5%) patients with CP had steatorrhoea when assessed by the acid steatocrit method; 79 (68.1%) with CP had exocrine insufficiency by the FE-1 test (χ² test, P < 0.001). The results of acid steatocrit and FE-1 showed a significant negative correlation (Spearman's rho = -0.376, P < 0.001). A statistically significant difference was seen between the M-ANNHEIM stages as classified separately by acid steatocrit and the FE-1. Thirteen (6.7%), 87 (44.8%), 89 (45.8%) and 5 (2.5%) patients were placed in M-ANNHEIM stages 0, I, II, and III respectively, with the use of acid steatocrit as against 13 (6.7%), 85 (43.8%), 75 (38.6%), and 21 (10.8%) respectively by FE-1 in stages 0, I, II, and III thereby altering the stage in 28 (14.4%) patients (P < 0.001, McNemar's test).

CONCLUSION

FE-1 estimation performed better than the acid steatocrit test for use in the staging of pancreatitis by the M-ANNHEIM classification since it diagnosed a higher proportion of patients with exocrine insufficiency.

MRI assessed pancreatic morphology and exocrine function are associated with disease burden in chronic pancreatitis

BACKGROUND AND AIM

The aim of this study was to explore the association between morphological and functional secretin-stimulated MRI parameters with hospitalization, quality of life (QOL), and pain in patients with chronic pancreatitis (CP).

PATIENTS AND METHODS

This prospective cohort study included 82 patients with CP. Data were obtained from clinical information, QOL, and pain as assessed by questionnaires (The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire and modified Brief Pain Inventory short form). Secretin-stimulated MRI morphological parameters included pancreatic gland volume, main pancreatic duct diameter, the modified Cambridge Classification of Duct Abnormality, apparent diffusion coefficient, fat signal fraction, and the pancreatic secretion volume as a functional parameter. The primary outcomes were time to first hospitalization related to the CP, as well as annual hospitalization frequency and duration. The secondary outcomes were pain severity, QOL, and pain interference scores.

RESULTS

A main pancreatic duct diameter below 5 mm was associated with reduced time to first hospitalization (hazard ratio=2.06; 95% confidence interval: 1.02-4.17; P=0.043). Pancreatic secretion volume was correlated with QOL (r=0.31; P=0.0072) and pain interference score (r=-0.27; P=0.032), and fecal elastase was also correlated with QOL (r=0.28; P=0.017). However, functional and morphological findings were not related to pain intensity.

CONCLUSION

Advanced pancreatic imaging techniques may be a highly sensitive tool for prognostication and monitoring of disease activity and its consequences.

The Impact of Risk Factors of Chronic Pancreatitis on Secretin Pancreatic Function Testing: Results of a 20-Year Study

OBJECTIVES

The aim of this study was to determine the effect of established risk factors on the outcome of secretin pancreatic function testing (sPFT) in patients undergoing work-up for suspected chronic pancreatitis.

METHODS

We completed a retrospective review of patients who underwent sPFT for suspected chronic pancreatitis over 20 years. We compared peak bicarbonate concentrations between groups and completed univariate and multivariate analyses to determine associations between risk factors and positive sPFT results (peak bicarbonate <80 mEq/L).

RESULTS

Forty-three of 162 patients had positive sPFT results. There were significant differences in peak bicarbonate concentrations in patients with and without recurrent acute pancreatitis (RAP) and with local complications from acute pancreatitis (AP) (P ≤ 0.05). The bicarbonate concentration in patients with and without other risk factors such as tobacco use, alcohol use, and family history of pancreatitis was not significantly different. Female sex, a history of AP, and a history of RAP were associated with positive sPFT results on univariate analysis (P ≤ 0.05). On multivariate analysis, sex and RAP remained significant.

CONCLUSIONS

Our study demonstrates that female sex, history of AP and RAP, and AP with local complications are associated with positive sPFT results or lower peak bicarbonate concentration. However, other risk factors do not impact the results of sPFT.

Chronic Pancreatitis: Current Status and Challenges for Prevention and Treatment

This paper reviews the current status of our understanding of the epidemiology, diagnosis, and management of the continuum of pancreatic diseases from acute and recurrent acute pancreatitis to chronic pancreatitis and the diseases that are often linked with pancreatitis including diabetes mellitus and pancreatic cancer. In addition to reviewing the current state of the field, we identify gaps in knowledge that are necessary to address to improve patient outcomes in these conditions.

Diagnosing Chronic Pancreatitis

Diagnosing CP can range from routine in those with severe disease and obvious calcifications on CT imaging to elusive in those patients with early changes in CP. The workup of suspected CP should follow a progressively noninvasive to more invasive STEP-wise approach in a patient with a suspicious clinical presentation and risk factors that raise their pretest probability of disease. After a thorough history and physical examination, basic laboratories should be obtained such as lipase, amylase, metabolic panel, and indirect PFTs (fecal elastase-1, serum trypsin). Computed tomography remains the best initial imaging modality to obtain as it has good sensitivity for severe CP and may obviate the need for other diagnostic tests. When equivocal, an MRCP should be obtained for a more detailed evaluation of the both the pancreatic parenchyma and ducts. If the diagnosis remains in doubt, EUS should be performed with or without pancreas function testing. ERCP remains a last-line diagnostic test and seldom should be used outside of therapeutic purposes. Future advances should target optimizing current diagnostic tools to more accurately diagnose early CP, as it is in this population where the benefits of delaying progression of CP may have the most profound effect. Likely the best way at establishing a diagnosis in these patients is via pancreatic function testing in the setting of indeterminate EUS results. Biomarker studies of pancreas fluid may supplement diagnosis.

Comparison of Combined Endoscopic Ultrasonography and Endoscopic Secretin Testing With the Traditional Secretin Pancreatic Function Test in Patients With Suspected Chronic Pancreatitis: A Prospective Crossover Study

OBJECTIVE

We aimed to determine the feasibility and accuracy of a combined endoscopic ultrasonography (EUS) with a shortened pancreatic function testing (sEUS) for structural and functional assessment using a single instrument in patients with suspected chronic pancreatitis (CP).

METHODS

We completed a prospective crossover study, enrolling patients with suspected CP. Patients who underwent both traditional 1-hour secretin pancreatic function test (sPFT) and sEUS were included in the analysis. We compared study results for test concordance and for correlation of peak bicarbonate concentrations.

RESULTS

Eleven (64.7%) of 17 patients had concordant sPFT and sEUS findings when the cutoff for peak bicarbonate was 80 mEq/L. Six patients had discordant findings with a negative sPFT and positive sEUS. This poor concordance suggests that sEUS is an unreliable functional test. Lowering the sEUS cutoff to 70 mEq/L resulted in improved concordance (64.7% vs 70.6%). Finally, there was no significant correlation between peak bicarbonate concentrations (r = 0.47; 95% confidence interval, -0.02 to 0.79) in these 2 functional tests.

CONCLUSIONS

We demonstrate poor concordance between sPFT and sEUS suggesting that a combined shortened functional and structural test using a single instrument may not be a feasible test for diagnosis of suspected CP when a cutoff of 80 mEq/L is used.

Potential for Screening for Pancreatic Exocrine Insufficiency Using the Fecal Elastase-1 Test

The early diagnosis of pancreatic exocrine insufficiency (PEI) is hindered because many of the functional diagnostic techniques used are expensive and require specialized facilities, which prevent their widespread availability. We have reviewed current evidence in order to compare the utility of these functional diagnostic techniques with the fecal elastase-1 (FE-1) test in the following three scenarios: screening for PEI in patients presenting with symptoms suggestive of pancreatic disease, such as abdominal pain or diarrhea; determining the presence of PEI in patients with an established diagnosis of pancreatic disease, such as chronic pancreatitis or cystic fibrosis; determining exocrine status in disorders not commonly tested for PEI, but which have a known association with this disorder. Evidence suggests the FE-1 test is reliable for the evaluation of pancreatic function in many pancreatic and non-pancreatic disorders. It is non-invasive, is less time-consuming, and is unaffected by pancreatic enzyme replacement therapy. Although it cannot be considered the gold-standard method for the functional diagnosis of PEI, the advantages of the FE-1 test make it a very appropriate test for screening patients who may be at risk of this disorder.

Comparing acid steatocrit and faecal elastase estimations for use in M-ANNHEIM staging for pancreatitis

AIM

To compare two tests for exocrine pancreatic function (EPF) for use in M-ANNHEIM staging for pancreatitis.

METHODS

One hundred and ninety four consecutive patients with acute pancreatitis (AP; n = 13), recurrent acute pancreatitis (RAP; n = 65) and chronic pancreatitis (CP; n = 116) were enrolled. EPF was assessed by faecal elastase-1 (FE-1) estimation and stool fat excretion by the acid steatocrit method. Patients were classified as per M-ANNHEIM stages separately based on the results of the two tests for comparison. Independent Student’s t-test, χ² test, Kruskal-Wallis test, Mann-Whitney U test and McNemar’s test were used as appropriate.

RESULTS

Sixty-one (52.5%) patients with CP had steatorrhoea when assessed by the acid steatocrit method; 79 (68.1%) with CP had exocrine insufficiency by the FE-1 test (χ² test, P < 0.001). The results of acid steatocrit and FE-1 showed a significant negative correlation (Spearman’s rho = -0.376, P < 0.001). A statistically significant difference was seen between the M-ANNHEIM stages as classified separately by acid steatocrit and the FE-1. Thirteen (6.7%), 87 (44.8%), 89 (45.8%) and 5 (2.5%) patients were placed in M-ANNHEIM stages 0, I, II, and III respectively, with the use of acid steatocrit as against 13 (6.7%), 85 (43.8%), 75 (38.6%), and 21 (10.8%) respectively by FE-1 in stages 0, I, II, and III thereby altering the stage in 28 (14.4%) patients (P < 0.001, McNemar’s test).

CONCLUSION

FE-1 estimation performed better than the acid steatocrit test for use in the staging of pancreatitis by the M-ANNHEIM classification since it diagnosed a higher proportion of patients with exocrine insufficiency.

Label-free fluorometric detection of chymotrypsin activity using graphene oxide/nucleic-acid-stabilized silver nanoclusters hybrid materials

Pancreatic function tests are used to determine the presence of chronic pancreatitis, particularly in the early stage of the disease. Chymotrypsin is an indicator of pancreatic function and is thus related to pancreatic diseases. A new fluorescent biosensing method for assay of chymotrypsin activity was developed using DNA (dC12)-templated silver nanoclusters and graphene oxide (GO). A peptide probe was also designed using chymotrypsin-cleavable amino acid sequence and a cysteine terminus. The peptide probe formed Ag-S bond to dC12-AgNCs to enhance the fluorescence of dC12-AgNCs. After the addition of GO, the peptide was adsorbed to the negative GO surface and the fluorescence of dC12-AgNCs was quenched by FRET. The peptide was then degraded into amino acid fragments upon addition of chymotrypsin; these fragments were released from the GO surface, and the FRET was terminated. The developed label-free method features lower cost and higher sensitivity to chymotrypsin activity assay compared with conventional fluorescence analysis. The method can be used to analyze chymotrypsin (as low as 3ng/mL, signal/noise =3) across a dynamic range of 0.0-50.0ng/mL. The proposed biosensing strategy can also be extended to other proteases by using different peptide substrates.

Practical guide to exocrine pancreatic insufficiency - Breaking the myths

BACKGROUND

Exocrine pancreatic insufficiency (EPI) is characterized by a deficiency of exocrine pancreatic enzymes, resulting in malabsorption. Numerous conditions account for the etiology of EPI, with the most common being diseases of the pancreatic parenchyma including chronic pancreatitis, cystic fibrosis, and a history of extensive necrotizing acute pancreatitis. Treatment for EPI includes dietary management, lifestyle changes (i.e., decrease in alcohol consumption and smoking cessation), and pancreatic enzyme replacement therapy.

DISCUSSION

Many diagnostic tests are available to diagnose EPI, however, the criteria of choice remain unclear and the causes for a false-positive test are not yet understood. Despite multiple studies on the treatment of EPI using exogenous pancreatic enzymes, there remains confusion amongst medical practitioners with regard to the best approach to diagnose EPI, as well as dosing and administration of pancreatic enzymes. Appropriate use of diagnostics and treatment approaches using pancreatic enzymes in EPI is essential for patients. This opinion piece aims to address the existing myths, remove the current confusion, and function as a practical guide to the diagnosis and treatment of EPI.

Chronic Diarrhea: Diagnosis and Management

Chronic diarrhea is a common problem affecting up to 5% of the population at a given time. Patients vary in their definition of diarrhea, citing loose stool consistency, increased frequency, urgency of bowel movements, or incontinence as key symptoms. Physicians have used increased frequency of defecation or increased stool weight as major criteria and distinguish acute diarrhea, often due to self-limited, acute infections, from chronic diarrhea, which has a broader differential diagnosis, by duration of symptoms; 4 weeks is a frequently used cutoff. Symptom clusters and settings can be used to assess the likelihood of particular causes of diarrhea. Irritable bowel syndrome can be distinguished from some other causes of chronic diarrhea by the presence of pain that peaks before defecation, is relieved by defecation, and is associated with changes in stool form or frequency (Rome criteria). Patients with chronic diarrhea usually need some evaluation, but history and physical examination may be sufficient to direct therapy in some. For example, diet, medications, and surgery or radiation therapy can be important causes of chronic diarrhea that can be suspected on the basis of history alone. Testing is indicated when alarm features are present, when there is no obvious cause evident, or the differential diagnosis needs further delineation. Testing of blood and stool, endoscopy, imaging studies, histology, and physiological testing all have roles to play but are not all needed in every patient. Categorizing patients after limited testing may allow more directed testing and more rapid diagnosis. Empiric antidiarrheal therapy can be used to mitigate symptoms in most patients for whom a specific treatment is not available.

Can We Detect Chronic Pancreatitis With Low Serum Pancreatic Enzyme Levels?

OBJECTIVES

The aims of this study were to evaluate whether serum pancreatic enzyme levels could be used to aid screening for chronic pancreatitis (CP).

METHODS

170 healthy volunteers were screened and prospectively enrolled in the control group. 150 patients who were diagnosed with calcific CP were enrolled in the patient group by retrospective review. Serum amylase and lipase levels were compared between the 2 groups.

RESULTS

The mean values ± SD of the control group were compared with those of the patient group for serum amylase level (48.1 ± 13.2 vs 34.8 ± 17.2 U/L, P < 0.001) and serum lipase level (26.4 ± 11.3 vs 16.3 ± 11.2 U/L, P < 0.001). On the receiver operating characteristic curve analysis for amylase level, area under the curve was 0.740 (95% confidence interval), and sensitivity and specificity were 38.7% and 94.1%, respectively, with a cutoff value of 27.5 U/L. On the receiver operating characteristic curve analysis for lipase level, area under the curve was 0.748 (95% confidence interval), and sensitivity and specificity were 33.3% and 95.9%, respectively, with a cutoff value of 10.5 U/L.

CONCLUSIONS

Our results suggest that low serum pancreatic enzyme levels can be used to aid in detection of CP.

Glucagon-like peptide-1 receptor agonist exenatide has no acute effect on MRI-measured exocrine pancreatic function in patients with type 2 diabetes: a randomized trial

AIMS

To investigate the effect of infusion of the glucagon-like peptide-1 (GLP-1) receptor agonist exenatide on exocrine pancreatic function.

METHODS

This was a randomized, placebo-controlled, double-blind, crossover study in 12 male patients with type 2 diabetes, treated with oral glucose-lowering agents. On two separate occasions, exenatide or placebo (saline 0.9%) were administered intravenously, in randomized order. Exocrine pancreatic function was measured using secretin-enhanced magnetic resonance cholangiopancreatography. The primary outcome measure was defined as secretin-stimulated pancreatic excretion volume. Secondary outcome measures were maximum secretion speed and the time to reach this maximum. In addition, changes in pancreatic duct (PD) diameter were measured.

RESULTS

Exenatide did not change secretin-stimulated pancreatic excretion volume, as compared with placebo (mean ± standard error of the mean 142.2 ± 15.6 ml vs 142.6 ± 8.5 ml, respectively; p = 0.590). Also, exenatide did not change the maximum secretion speed (33.1 ± 1.4 vs 36.9 ± 2.2; p = 0.221), nor the time to reach this maximum (both 4 min 30 s). No differences in PD diameter were observed between the two groups.

CONCLUSIONS

Infusion of exenatide did not directly influence MRI-measured exocrine pancreatic excretion in patients with type 2 diabetes. Although long-term studies are warranted, these findings suggest that potential adverse pancreatic effects of GLP-1 receptor agonists are not mediated by changes in exocrine pancreatic secretion.

Evaluation of Qualitative Magnetic Resonance Imaging Features for Diagnosis of Chronic Pancreatitis

OBJECTIVES

The purpose of this study was to determine qualitative pancreatic magnetic resonance imaging (MRI) features that must be present to predict abnormal pancreatic secretory function in patients evaluated for chronic pancreatitis (CP).

METHODS

The MRIs of study subjects were reviewed by 2 abdominal radiologists; qualitative parenchyma and ductal features were recorded. Endoscopic pancreatic function test (ePFT) results (reference standard) were classified as normal (peak pancreatic fluid bicarbonate [HCO3-] ≥75 meq/L) or abnormal (<75). Abnormal ePFT was further classified as mild/moderate (74-65) and marked deficiency (<65). Statistical analysis was performed to assess the association between MRI features and abnormal ePFT.

RESULTS

The study cohort was composed of 93 subjects, mean age 49 years (range, 18-78 years), 65% females. Univariate analysis identified 9 qualitative MRI features significantly (P < 0.05) associated with abnormal pancreatic secretory function. Number of MRI features increases as peak pancreatic fluid [HCO3-] decreases (Pearson r = -0.629; P = 0.001). Receiver operating characteristic curve analysis determined that a threshold of 6 or more associated MRI features 64% sensitive and 94% specific for marked bicarbonate deficiency.

CONCLUSIONS

Qualitative MRI parenchymal and ductal features are associated with CP. Presence of 6 or more features results in a higher specificity for the diagnosis of CP in advanced disease.

ESPGHAN and NASPGHAN Report on the Assessment of Exocrine Pancreatic Function and Pancreatitis in Children

The purpose of this clinical report is to discuss several recent advances in assessing exocrine pancreatic insufficiency (EPI) and pancreatitis in children, to review the array of pancreatic function tests, to provide an update on the inherited causes of EPI, with special emphasis on newly available genetic testing, and to review newer methods for evaluating pancreatitis.

Diagnostic accuracy of secretin-stimulated ultrasonography of the pancreas assessing exocrine pancreatic failure in cystic fibrosis and chronic pancreatitis

OBJECTIVE

Volume output failure is a feature of decreasing exocrine pancreatic function. This parameter is assessed by secretin-stimulated MRI in several studies. Our purpose was to evaluate ultrasonography of the fluid in the descending duodenum and Wirsung duct (WD) after secretin stimulation as a measure of pancreatic fluid flow in patients expected to have severe output failure.

MATERIAL AND METHODS

We included subjects with chronic pancreatitis (CP), cystic fibrosis (CF) and a group of healthy controls in a prospective observation study. Transabdominal ultrasonography was performed before and during 15 min after secretin i.v. duodenal juice was collected by endoscopic short test (EST), and bicarbonate concentration measured. Patient groups were classified according to exocrine pancreatic function.

RESULTS

Pancreatic insufficient CF (CFI) patients and CP insufficient (CPI) patients showed less duodenal fluid filling compared to other groups (p < 0.001). Measures of the WD diameter could only identify the most severe failure in the CFI group (p < 0.001).

CONCLUSION

Secretin-stimulated ultrasonography can be used to assess pancreatic fluid flow and may be combined with EST in the evaluation of exocrine pancreatic function. Fluid filling in the descending part of duodenum was the most accurate predictor of pancreatic insufficiency in both patient groups. The test demonstrated better diagnostic accuracy diagnosing exocrine pancreatic failure in the CF patients than in CP patients.

Approach to patients with suspected chronic pancreatitis: a comprehensive review

Chronic pancreatitis (CP) represents a significant health care burden in the United States. Diagnosing it early and accurately is important for the efficient management of these patients. However, the early diagnosis of CP, when structural and functional pancreatic changes are subtle, remains difficult. Complicating this is the large cohort of patients with nonspecific abdominal pain who are often suspected of having early CP and who utilize significant health care resources in attempts at diagnosis and management. We present a review of the current diagnostic tests available for making an early diagnosis of CP. We further report our approach to patients suspected of having CP based on the available literature.

American Pancreatic Association Practice Guidelines in Chronic Pancreatitis: evidence-based report on diagnostic guidelines

The diagnosis of chronic pancreatitis remains challenging in early stages of the disease. This report defines the diagnostic criteria useful in the assessment of patients with suspected and established chronic pancreatitis. All current diagnostic procedures are reviewed, and evidence-based statements are provided about their utility and limitations. Diagnostic criteria for chronic pancreatitis are classified as definitive, probable, or insufficient evidence. A diagnostic (STEP-wise; survey, tomography, endoscopy, and pancreas function testing) algorithm is proposed that proceeds from a noninvasive to a more invasive approach. This algorithm maximizes specificity (low false-positive rate) in subjects with chronic abdominal pain and equivocal imaging changes. Furthermore, a nomenclature is suggested to further characterize patients with established chronic pancreatitis based on TIGAR-O (toxic, idiopathic, genetic, autoimmune, recurrent, and obstructive) etiology, gland morphology (Cambridge criteria), and physiologic state (exocrine, endocrine function) for uniformity across future multicenter research collaborations. This guideline will serve as a baseline manuscript that will be modified as new evidence becomes available and our knowledge of chronic pancreatitis improves.

13C-mixed triglyceride breath test for evaluation of pancreatic exocrine function in diabetes mellitus

OBJECTIVE

The clinical relevance of pancreatic exocrine insufficiency (PEI) in diabetic patients is unclear mostly because established function tests are invasive and expensive or lack sensitivity and specificity. A modified version of the noninvasive 13C-mixed triglyceride breath test (13C-MTGT) has recently been shown to detect moderate PEI reliably in patients with chronic pancreatitis. Its sensitivity and specificity in other patient groups are unknown. We therefore aimed to clarify the significance of this test for patients with diabetes mellitus (DM).

METHODS

A secretin cerulein test and a modified 13C-MTGT were performed in 14 patients with DM (10 patients with type 1 DM) and 10 healthy volunteers.

RESULTS

Secretin cerulein test showed significantly lower outputs of amylase, trypsin, and lipase in DM compared with healthy volunteers (P < 0.05). Likewise, 13C-MTGT showed significantly lower maximal and cumulative 13C-exhalation in DM (P < 0.005). Stimulated lipase output correlated with cumulative 13C-exhalation (P < 0.05). However, when compared with normal values, only 2 patients with diabetes had abnormally low lipase output, whereas cumulative 13C-exhalation was pathologically decreased in 8 patients, including those with decreased lipase output.

CONCLUSIONS

The noninvasive 13C-MTGT can detect mild to moderate PEI in DM. However, the specificity of the 13C-MTGT is low in these patients probably because nonpancreatic mechanisms contribute to decreased intestinal lipolysis.