Influence of jejunal morphology changes on exocrine pancreatic function in celiac disease

Pancreatic involvement in celiac disease

Celiac disease (CD) is well recognized as a systemic, chronic autoimmune disease mainly characterized by gluten-sensitive enteropathy in genetically predisposed individuals but with various extraintestinal features. One of the affected organs in CD is the pancreas, consisting of both endocrine and exocrine alterations. Over the last decades there has been increasing interest in the pancreatic changes in CD, and this has been reflected by a great number of publications looking at this extraintestinal involvement during the course of CD. While pancreatic endocrine changes in CD, focusing on type 1 diabetes mellitus, are well documented in the literature, the relationship with the exocrine pancreas has been less studied. This review summarizes currently available evidence with regard to pancreatic exocrine alterations in CD, focusing on risk of pancreatitis in CD patients, association with autoimmune pancreatitis, prevalence and outcomes of pancreatic exocrine insufficiency in newly diagnosed and gluten-free diet treated CD patients, and the link with cystic fibrosis. In addition, we discuss mechanisms behind the associated pancreatic exocrine impairment in CD and highlight the recommendations for clinical practice.

The Risk of Acute and Chronic Pancreatitis in Celiac Disease

BACKGROUND AND AIMS

Celiac disease (CD) is a chronic immune-mediated enteropathy that is precipitated by dietary gluten in genetically predisposed individuals. A few studies reported a higher incidence of pancreatitis in the CD population. Using a large US database, we sought to describe the epidemiology, risk, and outcomes of acute pancreatitis (AP) and chronic pancreatitis (CP) in CD patients.

METHODS

We queried a multiple health system data analytics and research platform (Explorys Inc, Cleveland, OH, USA). A cohort of patients with a diagnosis of CD was identified. Subsequently, individuals who developed a new diagnosis of AP and CP after at least 30 days of being diagnosed with CD were identified. A multivariate regression model was performed to adjust for multiple confounding factors.

RESULTS

Of the 72,965,940 individuals in the database, 133,400 (0.18%), 362,050 (0.50%), and 95,190 (0.13%) had CD, AP, and CP, respectively. New diagnosis of AP and CP after at least 30 days of CD diagnosis was 1.06%, 0.52%, respectively, compared to non-CD patients with 0.49% for AP and 0.13% for CP, P < .0001. In multivariate regression analysis, patients with CD were at higher risk of developing AP [OR 2.66; 95% CI 2.55-2.77] and CP [OR 2.18; 95% CI 2.04-2.34]. Idiopathic AP was the most common etiology among CD patients [OR 1.54; 95% CI 1.34-1.77].

CONCLUSIONS

In this largest US population database and after adjusting for several confounders, patients with CD were at increased risk of developing AP and CP. Celiac disease patients had worse outcomes and higher medical burden compared to non-CD patients. Recurrent abdominal pain that suggests pancreatic etiology, idiopathic pancreatitis, or elevation of pancreatic enzymes should warrant investigation for CD as a potential cause of pancreatic disease.

Dietary Considerations in Autism Spectrum Disorders: The Potential Role of Protein Digestion and Microbial Putrefaction in the Gut-Brain Axis

Children with autism spectrum disorders (ASD), characterized by a range of behavioral abnormalities and social deficits, display high incidence of gastrointestinal (GI) co-morbidities including chronic constipation and diarrhea. Research is now increasingly able to characterize the “fragile gut” in these children and understand the role that impairment of specific GI functions plays in the GI symptoms associated with ASD. This mechanistic understanding is extending to the interactions between diet and ASD, including food structure and protein digestive capacity in exacerbating autistic symptoms. Children with ASD and gut co-morbidities exhibit low digestive enzyme activity, impaired gut barrier integrity and the presence of antibodies specific for dietary proteins in the peripheral circulation. These findings support the hypothesis that entry of dietary peptides from the gut lumen into the vasculature are associated with an aberrant immune response. Furthermore, a subset of children with ASD exhibit high concentrations of metabolites originating from microbial activity on proteinaceous substrates. Taken together, the combination of specific protein intakes poor digestion, gut barrier integrity, microbiota composition and function all on a background of ASD represents a phenotypic pattern. A potential consequence of this pattern of conditions is that the fragile gut of some children with ASD is at risk for GI symptoms that may be amenable to improvement with specific dietary changes. There is growing evidence that shows an association between gut dysfunction and dysbiosis and ASD symptoms. It is therefore urgent to perform more experimental and clinical research on the “fragile gut” in children with ASD in order to move toward advancements in clinical practice. Identifying those factors that are of clinical value will provide an evidence-based path to individual management and targeted solutions; from real time sensing to the design of diets with personalized protein source/processing, all to improve GI function in children with ASD.

Introduction and practical approach to exocrine pancreatic insufficiency for the practicing clinician

AIMS

In exocrine pancreatic insufficiency (EPI), the quantity and/or activity of pancreatic digestive enzymes are below the levels required for normal digestion, leading to maldigestion and malabsorption. Diagnosis of EPI is often challenging because the characteristic signs and symptoms overlap with those of other gastrointestinal conditions. Additionally, there is no single convenient, or specific diagnostic test for EPI. The aim of this review is to provide a framework for differential diagnosis of EPI vs other malabsorptive conditions.

METHODS

This is a non-systematic narrative review summarising information pertaining to the aetiology, diagnosis and management of EPI.

RESULTS

Exocrine pancreatic insufficiency may be caused by pancreatic disorders, including chronic pancreatitis, cystic fibrosis, pancreatic resection and pancreatic cancer. EPI may also result from extra-pancreatic conditions, including coeliac disease, Zollinger-Ellison syndrome and gastric surgery. Timely and accurate diagnosis of EPI is important, as delays in treatment prolong maldigestion and malabsorption, with potentially serious consequences for malnutrition, overall health and quality of life. Symptoms of EPI are non-specific; therefore, a high index of clinical suspicion is required to make a correct diagnosis.

Personalizing protein nourishment

Proteins are not equally digestible-their proteolytic susceptibility varies by their source and processing method. Incomplete digestion increases colonic microbial protein fermentation (putrefaction), which produces toxic metabolites that can induce inflammation in vitro and have been associated with inflammation in vivo. Individual humans differ in protein digestive capacity based on phenotypes, particularly disease states. To avoid putrefaction-induced intestinal inflammation, protein sources, and processing methods must be tailored to the consumer's digestive capacity. This review explores how food processing techniques alter protein digestibility and examines how physiological conditions alter digestive capacity. Possible solutions to improving digestive function or matching low digestive capacity with more digestible protein sources are explored. Beyond the ileal digestibility measurements of protein digestibility, less invasive, quicker and cheaper techniques for monitoring the extent of protein digestion and fermentation are needed to personalize protein nourishment. Biomarkers of protein digestive capacity and efficiency can be identified with the toolsets of peptidomics, metabolomics, microbial sequencing and multiplexed protein analysis of fecal and urine samples. By monitoring individual protein digestive function, the protein component of diets can be tailored via protein source and processing selection to match individual needs to minimize colonic putrefaction and, thus, optimize gut health.

Coeliac disease in infants: antibodies to deamidated gliadin peptide come first!

Background

The onset of coeliac disease (CD) in the first year of life is uncommon and the diagnosis can be challenging due to the suboptimal sensitivity of tissue transglutaminase antibodies (tTG) at this age and the many other possible causes of malabsorption in infants. Antibodies to deamidated gliadin peptides (anti-DGPs), especially IgG, may appear earlier than IgA anti-tTG in very young children with CD.

Case presentation

We report here on an 8-month-old child who was evaluated for failure to thrive, constipation and developmental delay. The symptoms started following gluten introduction in the diet. Laboratory tests showed high fecal elastase concentration, normal serum IgA levels with positive IgG and IgA anti-DGPs, whereas anti-tTG were not detected. The duodenal biopsy revealed a complete villous atrophy (Marsh-Oberhuber 3C). The culture of biopsy fragments in the presence of gliadin peptides did not stimulate the production of IgA anti-endomysial antibodies. Genetic testing proved the child was positive for HLA-DQ2 (DQA1*05; DQB1*02) and HLA-DQ8 (DQA1*03, DQB1*0302). Having initiated the gluten-free diet, the symptoms disappeared and the infant experienced rapid catch-up growth with normalization of psychomotor development.

Conclusions

This case report highlights the utility of anti-DGPs for screening infants with suspected CD. The pattern with positivity for IgG and IgA anti-DGPs only is rare in IgA-competent children with biopsy-proven CD. It could be explained in infancy as immaturity of the adaptive immune system.

Sensitization to and Challenge with Gliadin Induce Pancreatitis and Extrapancreatic Inflammation in HLA-DQ8 Mice: An Animal Model of Type 1 Autoimmune Pancreatitis

BACKGROUND/AIMS

The aim of this study was to establish a pathogenetic mechanism of pancreatitis in celiac disease and IgG4-related disease using gluten-sensitive human leukocyte antigen (HLA)-DQ8 transgenic mice.

METHODS

Transgenic mice expressing HLA-DQ8 genes were utilized. Control mice were not sensitized but were fed gliadin-free rice cereal. Experimental groups consisted of gliadin-sensitized and gliadin-challenged mice; nonsensitized mice with cerulein hyperstimulation; and gliadin-sensitized and gliadinchallenged mice with cerulein hyperstimulation.

RESULTS

Gliadin-sensitized and gliadin-challenged mice with cerulein hyperstimulation showed significant inflammatory cell infiltrates, fibrosis and acinar atrophy compared with the control mice and the other experimental groups. The immunohistochemical analysis showed greater IgG1-positive plasma cells in the inflammatory infiltrates of gliadin-sensitized and gliadin-challenged mice with cerulein hyperstimulation compared with the control mice and the other experimental groups. Gliadin-sensitized and gliadin-challenged mice with cerulein hyperstimulation or gliadin-sensitized and gliadinchallenged mice showed IgG1-stained inflammatory cell infiltrates in the extrapancreatic organs, including the bile ducts, salivary glands, kidneys, and lungs.

CONCLUSIONS

Gliadinsensitization and cerulein hyperstimulation of gluten-sensitive HLA-DQ8 transgenic mice resulted in pancreatitis and extrapancreatic inflammation. This animal model suggests that chronic gliadin ingestion in a susceptible individual with the HLA-DQ8 molecule may be associated with pancreatitis and extrapancreatic inflammation.

Summary and recommendations from the Australasian guidelines for the management of pancreatic exocrine insufficiency

AIM

Because of increasing awareness of variations in the use of pancreatic exocrine replacement therapy, the Australasian Pancreatic Club decided it was timely to re-review the literature and create new Australasian guidelines for the management of pancreatic exocrine insufficiency (PEI).

METHODS

A working party of expert clinicians was convened and initially determined that by dividing the types of presentation into three categories for the likelihood of PEI (definite, possible and unlikely) they were able to consider the difficulties of diagnosing PEI and relate these to the value of treatment for each diagnostic category.

RESULTS AND CONCLUSIONS

Recent studies confirm that patients with chronic pancreatitis receive similar benefit from pancreatic exocrine replacement therapy (PERT) to that established in children with cystic fibrosis. Severe acute pancreatitis is frequently followed by PEI and PERT should be considered for these patients because of their nutritional requirements. Evidence is also becoming stronger for the benefits of PERT in patients with unresectable pancreatic cancer. However there is as yet no clear guide to help identify those patients in the 'unlikely' PEI group who would benefit from PERT. For example, patients with coeliac disease, diabetes mellitus, irritable bowel syndrome and weight loss in the elderly may occasionally be given a trial of PERT, but determining its effectiveness will be difficult. The starting dose of PERT should be from 25,000-40,000 IU lipase taken with food. This may need to be titrated up and there may be a need for proton pump inhibitors in some patients to improve efficacy.

Exocrine pancreatic insufficiency, MRI of the pancreas and serum nutritional markers in patients with coeliac disease

OBJECTIVES

To determine whether exocrine pancreatic function is impaired in patients with coeliac disease (CD) in our population and to evaluate its clinical importance.

METHODS

Pancreatic exocrine function was determined by measuring faecal elastase-1 (FE) concentration. CD was diagnosed by serological testing using IgA anti-tissue transglutaminase antibody (IgAtTg) and small bowel biopsy using the Marsh classification. MRI of the pancreas was performed to evaluate any morphological changes. The study took place from January 2012 to December 2013.

RESULTS

90 patients (73 women and 17 men) of mean age 43.8±17.7 years (range 20-80) were included in the study. Mean time from CD confirmation was 5.8±0.7 years (range 1-25). Exocrine pancreatic insufficiency (EPI) was diagnosed in four (4.4%) patients (one with mild EPI and three with severe EPI). MRI showed no morphological changes in any of the four patients. In all patients with EPI at least one serological nutritional marker was below the lower limit of normal.

CONCLUSIONS

EPI is present in a small number of patients with CD. EPI should be excluded in all patients with CD in the presence of overt malnutrition or in cases of persistent gastrointestinal symptoms despite a gluten-free diet. Measurement of a serum nutritional panel, regardless of the presence of clinical symptoms of EPI, can be of clinical importance. MRI should be performed to exclude any morphological change in the pancreas.

Effects on gut properties in exocrine pancreatic insufficient (EPI) pigs, being growth retarded due to pancreatic duct ligation at 7 weeks but not at 16 weeks of age

PURPOSE

Exocrine pancreatic insufficiency (EPI) induced in young pigs by pancreatic duct ligation (PDL) early after weaning result in total growth deprivation while it has little effect in somewhat older pigs. The main objective was to study effects of EPI on gut structure and function in littermate pigs underwent to PDL at different age.

MATERIAL/METHODS

Pigs, duct-ligated at either 7 (2 weeks post-weaning, PDL-7) or 16 weeks of age (PDL-16), and euthanized at an age of 21-23 weeks together with un-operated littermates were studied. The intestinal in vitro permeability was studied in separate PDL-pigs and compared to un-operated.

RESULTS

Morphometric analysis showed gut mucosal atrophy in the PDL-7 as compared to PDL-16 pigs, while no differences in mucosal disaccharidase activities. The intestinal permeability for different-sized markers was significantly increased in the PDL-pigs compared to the un-operated controls. Analyses of the intestinal digesta showed a total lack of pancreatic enzymes in all PDL-pigs, while instead new, as yet unidentified, enzyme-activities appeared.

CONCLUSIONS

All EPI-pigs, independent of age at PDL-operation, displayed adaptive gut changes, however the EPI-pigs operated early after weaning appeared more sensitive, probably related to their gut maturity and possibly explaining the growth arrest seen in these pigs.

Patients with celiac disease have an increased risk for pancreatitis

BACKGROUND & AIMS

Patients with celiac disease have been reported to be at increased risk for pancreatitis and pancreatic insufficiency, but the risk might have been overestimated because of patient selection and limited numbers of patients for analysis. Furthermore, no distinction has been made between patients with gallstone-related and non-gallstone-related pancreatitis. We performed a nationwide study to determine the risk for any pancreatitis or subtype of pancreatitis among patients with biopsy-verified celiac disease.

METHODS

We analyzed data from patients in Sweden with celiac disease (n = 28,908) who were identified on the basis of small intestinal biopsy records from 28 pathology departments (those with villous atrophy, Marsh 3). Biopsies were performed from 1969 to 2008, and biopsy report data were collected from 2006 to 2008. Patients with pancreatitis were identified on the basis of diagnostic codes in the Swedish Patient Register and records of pancreatic enzyme use in the Swedish Prescribed Drug Register. Data were matched with those from 143,746 individuals in the general population; Cox regression was used to estimate hazard ratios (HRs) for pancreatitis.

RESULTS

We identified 406 patients with celiac disease who were later diagnosed with pancreatitis (and 143 with expected pancreatitis) (HR, 2.85; 95% confidence interval [CI], 2.53-3.21). The absolute risk of any pancreatitis among patients with celiac disease was 126/100,000 person-years, with an excess risk of 81/100,000 person-years. The HR for gallstone-related acute pancreatitis was 1.59 (95% CI, 1.06-2.40), for non-gallstone-related acute pancreatitis HR was 1.86 (95% CI, 1.52-2.26), for chronic pancreatitis HR was 3.33 (95% CI, 2.33-4.76), and for supplementation with pancreatic enzymes HR was 5.34 (95% CI, 2.99-9.53). The risk of any pancreatitis within 5 years of diagnosis was 2.76 (95% CI, 2.36-3.22).

CONCLUSIONS

Based on an analysis of medical records from Sweden, patients with celiac disease have an almost 3-fold increase in risk of developing pancreatitis, compared with the general population.

Comparison of fecal elastase-1 and pancreatic function testing in children

OBJECTIVES

The fecal pancreatic elastase-1 (FE-1) test is considered a simple, noninvasive, indirect measure of pancreatic function. We aimed to evaluate the performance of the FE-1 test compared with the direct pancreatic function test (PFT) with secretin stimulation in children.

METHODS

Data of 70 children (6 months-17 years of age) who had both FE-1 test and PFT were analyzed.

RESULTS

The average FE-1 concentration was 403 ± 142 μg/g. Eleven children had concentrations below 200  μg/g, 23 between 201 to 500 μg/g, and 36 were above 500 μg/g. The average pancreatic elastase activity measured on direct stimulation was 49.1 ± 38.6  μmol · min (-1)· ml(-1) and 11 children had activity below the established cutoff (10.5 μmol · min(-1) · ml(-1)). Among the 11 children with pathologic PFT, 7 had normal FE-1, 4 were in the intermediate range (201-500 μg/g), and none were in the low range (<200 μg/g). Among the 59 children with normal direct PFT 11 (19%) had pathologic (<200 μg/g) and 19 (32%) had intermediate FE-1 tests. Twenty-nine children had both normal FE-1 concentration and normal PFT, giving a negative predictive value of 80%. The correlation between pancreatic elastase activity and FE-1 concentration was poor (r = 0.190). The sensitivity of the FE-1 test was found to be 41.7%, whereas the specificity was 49.2%. The positive predictive value of the FE-1 test was only 14%.

CONCLUSIONS

The FE-1 test is a simple, noninvasive, indirect method; however, ordering physicians should be aware of its limitations. It can give false-positive results and has low sensitivity in children with mild pancreatic insufficiency without cystic fibrosis and in those with isolated pancreatic enzyme deficiencies.

The role of fecal elastase-1 in detecting exocrine pancreatic disease

Exocrine pancreatic disease is thought to be uncommon in clinical practice and usually secondary to excess alcohol intake. Although excess alcohol intake does account for many cases of exocrine pancreatic disease, other conditions are associated with exocrine pancreatic insufficiency and such dysfunction perhaps occurs more frequently than conventionally expected. A reliable, patient-friendly, cheap and easy to use test for exocrine pancreatic disease is yet to be established; however, in many countries the main (and often only available) method of assessment of exocrine pancreatic function is the fecal-elastase-1 test. This Review examines the role of fecal-elastase-1 testing in detecting exocrine pancreatic insufficiency in a number of gastrointestinal and nongastrointestinal conditions and determines the value of pancreatic enzyme supplementation in these settings.

Pancreatic insufficiency in adult celiac disease: do patients require long-term enzyme supplementation?

BACKGROUND

Celiac disease is associated with exocrine pancreatic insufficiency. We previously reported that in 30% (20/66) of adult celiac patients with current or persistent diarrhea the underlying cause was exocrine pancreatic insufficiency. Of these 20 patients, 19 initially improved on pancreatic supplementation. To date, there are no published longitudinal studies.

METHODS

The 20 patients who had initially received therapy for exocrine pancreatic insufficiency were prospectively followed-up for 4 years. Gastrointestinal symptoms, dietary adherence, celiac antibody status, and dose of enzyme supplementation were recorded. Fecal elastase-1 (Fel-1) was repeated to reassess exocrine pancreatic function.

RESULTS

In the study, 19/20 patients were reviewed, as one had died (mean age 59.7 years, 7 males). The mean duration of celiac disease was 13.2 years. Eleven out of nineteen were still taking enzyme supplementation at a mean dose of 45,000 units of lipase per day. Only 1/11 reported no symptomatic benefit and 8/19 patients had discontinued supplementation because their diarrhea had improved. In the whole group there was a significant increase in Fel-1 levels over time, with median values of 90 μg/g at 0 months, 212 μg/g at 6 months, and 365 μg/g at follow-up (45-66 months)(p < 0.0001).

CONCLUSIONS

Fecal elastase-1 is useful in identifying exocrine pancreatic insufficiency in adult celiac patients with diarrhea. Our longitudinal data suggests that pancreatic enzyme supplementation could be discontinued in a substantial proportion of patients as symptoms improve.

Cystic Fibrosis Foundation practice guidelines for the management of infants with cystic fibrosis transmembrane conductance regulator-related metabolic syndrome during the first two years of life and beyond

Through early detection, newborn screening (NBS)(1) for cystic fibrosis (CF) offers the opportunity for early intervention and improved outcomes. NBS programs screen for hypertrypsinogenemia, and most also identify mutations in the CF transmembrane conductance regulator (CFTR) gene. Individuals identified by NBS are diagnosed with CF if they have an elevated sweat chloride level or if they have inherited 2 disease-causing mutations in the CFTR gene. Mutations in the CFTR gene can cause CF, but not all CFTR mutations are disease-causing. The term CFTR-related metabolic syndrome (CRMS) is proposed to describe infants identified by hypertrypsinogenemia on NBS who have sweat chloride values <60 mmol/L and up to 2 CFTR mutations, at least 1 of which is not clearly categorized as a "CF-causing mutation," thus they do not meet CF Foundation guidelines for the diagnosis of CF. With what is now near-universal CF NBS in the United States, an increasing number of infants with CRMS are being identified. Given our inadequate knowledge of the natural history of CRMS, standards for diagnosis, monitoring, and treatment are absent. This document aims to help guide the monitoring and care of individuals with CRMS while our knowledge base on appropriate management evolves.

Pancreatic endocrine and exocrine changes in celiac disease

Although there is a great deal of information on celiac disease and associated involvement of other non-intestinal sites, data on concomitant changes in the structure and function of the pancreas is limited. The present review critically examines pancreatic endocrine changes that have been well documented in the literature, including insulin-dependent diabetes mellitus. Pancreatic exocrine alterations may also occur, and if severe, marked malnutrition with pancreatic failure and ductal calcification have been observed. Finally, other pancreatic disorders have been recorded with celiac disease.

Comparison of monoclonal and polyclonal ELISAs for fecal elastase in patients with cystic fibrosis and pancreatic insufficiency

OBJECTIVES

Two enzyme-linked immunosorbent assay methodologies are used to detect pancreatic insufficiency: monoclonal and polyclonal. We sought to compare these assays in patients with cystic fibrosis and to correlate these with the coefficient of fat absorption (CFA).

STUDY DESIGN

As part of a larger study, subjects had stool elastase measured by both methods while taking exogenous enzymes. Subjects subsequently stopped enzymes and had a fecal fat balance study performed; the CFA was then calculated.

RESULTS

One hundred twenty-four subjects participated in this substudy. The median values for the monoclonal and polyclonal assays were 0.3 and 22.75 microg/g, respectively. The correlation coefficient between the 2 tests was 0.86 (P < 0.0001). The correlation coefficients between CFA and the monoclonal and polyclonal assays were 0.24 (P = 0.006) and 0.10 (P = 0.27), respectively. If the criterion standard definition of pancreatic insufficiency was set at a CFA < 90% and the test definition of pancreatic insufficiency was set at <100 microg/g, then the monoclonal and polyclonal assay positive predictive values were 97.6% (120 of 123) and 97.4% (111 of 114), respectively.

CONCLUSIONS

The positive predictive value of both monoclonal and polyclonal fecal elastase in patients with cystic fibrosis is extremely good; however, correlation of either test with CFA was poor. The median value for the polyclonal elastase assay is higher than for the monoclonal assay, which could potentially lead to lower sensitivity of the polyclonal assay at lower cutpoints for the monoclonal assay is used.

Is exocrine pancreatic insufficiency in adult coeliac disease a cause of persisting symptoms?

BACKGROUND

Patients with coeliac disease may have diarrhoea despite being on a gluten-free diet.

AIM

To assess whether exocrine pancreatic insufficiency causes persisting symptoms compared with controls, we determined whether pancreatic enzyme supplementation provided symptomatic benefit in coeliac patients with chronic diarrhoea.

METHODS

Patients (n = 259) were subdivided into four groups: (a) new coeliac disease (n = 57), (b) coeliac disease patients on a gluten-free diet without gastrointestinal symptoms (n = 86), (c) coeliac disease patients on a gluten-free diet with chronic diarrhoea (n = 66) and (d) patients with chronic diarrhoea without coeliac disease (n = 50). Stool frequency and weight, before and after treatment with pancreatic enzyme supplementation were recorded.

RESULTS

The prevalence of a low faecal elastase-1 within the groups was: group (A) six of 57 (11%), group (B) five of 86 (6%), group (C) 20 of 66 (30%) and group (D) two of 50 (4%). Low faecal elastase-1 was more frequent in coeliac disease patients with chronic diarrhoea vs. other subgroups of coeliac disease (P < or = 0.0001) and controls (P < or = 0.0003). In 18 of 20 stool frequency reduced following pancreatic enzyme supplementation from four per day to one (P < or = 0.001). No weight increase (P = 0.3) was observed.

CONCLUSIONS

Low faecal elastase is common in patients with coeliac disease and chronic diarrhoea, suggesting exocrine pancreatic insufficiency. In this group of patients, pancreatic enzyme supplementation may provide symptomatic benefit.

Subclinical exocrine pancreatic dysfunction resulting from decreased cholecystokinin secretion in the presence of intestinal villous atrophy

The aim of this study was to evaluate the concept that pancreatic dysfunction in patients having gluten sensitivity (celiac disease [CD]) or cow's milk protein enteropathy (CMPE) may result from the lack of pancreatic enzyme stimulation in the absence or decrease of cholecystokinin (CCK) secretion caused by villous atrophy.

PATIENTS AND METHODS

The following parameters were measured: plasma CCK in response to a fatty meal and human pancreatic fecal elastase in 24 patients with CD while on gluten-free diet and after gluten provocation and in 12 patients with CMPE at diagnosis and after a 6-month period of cow's milk-free diet. Intestinal mucosa morphology was examined by small bowel biopsy. Sixty-three controls having no organic gastrointestinal problems were investigated once at the time of diagnostic evaluation.

RESULTS

Fasting CCK, obtained at a time when patients with CD or CMPE had normal intestinal mucosa, was significantly different from postprandial and comparable to that of the control group. Fasting CCK obtained from patients with villous atrophy was also statistically different, but not significantly, from the postprandial. Fasting and postprandial plasma CCK and fecal pancreatic elastase values from patients having normal intestinal mucosa were significantly higher than those obtained from patients with villous atrophy. Significant correlation of intestinal mucosa morphology and CCK with fecal elastase concentration was documented.

CONCLUSION

Exocrine pancreatic dysfunction in individuals having villous atrophy may be the consequence of decreased CCK secretion. Cholecystokinin and pancreatic secretion is restored to normal, with intestinal mucosa regeneration.

Fecal elastase-1: utility in pancreatic function in cystic fibrosis

Early detection and management of pancreatic insufficiency is essential to optimize health and outcomes in cystic fibrosis patients. The gold standard measures for assessment of pancreatic function are direct pancreatic stimulation tests, which have numerous limitations. Estimation of fecal elastase-1 level to determine pancreatic function is an attractive alternative as the test is simple, rapid, cost-effective and easy to perform even in children. This review summarizes the data from studies reflecting the validity, limitation and advantages of fecal elastase-1 in assessing pancreatic function in cystic fibrosis patients.

Hepatobiliary and pancreatic disorders in celiac disease

A variety of hepatic and biliary tract disorders may complicate the clinical course of celiac disease. Some of these have been hypothesized to share common genetic factors or have a common immunopathogenesis, such as primary biliary cirrhosis, primary sclerosing cholangitis and autoimmune forms of hepatitis or cholangitis. Other hepatic changes in celiac disease may be associated with malnutrition resulting from impaired nutrient absorption, including hepatic steatosis. In addition, celiac disease may be associated with rare hepatic complications, such as hepatic T-cell lymphoma. Finally, pancreatic exocrine function may be impaired in celiac disease and represent a cause of treatment failure.

[Fecal elastase-1: a useful test in pediatric practice]

AIM

To study fecal elastase-1 (E1F) and chymotrypsin (ChT) in stools for the diagnosis of pancreatic insufficiency in pediatric practice.

MATERIALS AND METHODS

E1F and ChT were measured in stools of 198 children divided in 3 groups: 49 children without any digestive disease (group A), 71 children with pancreatic diseases (group B), and 78 children with non-pancreatic digestive diseases (group C).

RESULTS

In group B, E1F values were very low in 64 children and normal in 7 children without pancreatic insufficiency (6 children with cystic fibrosis and 1 with chronic pancreatitis). ChT values were normal in children without pancreatic insufficiency but also in half of children treated with pancreatic enzymes. Decreased E1F values were seen in 2 children (4%) in the group A and 22 children (28%) in the group C, especially those with acute gastroenteritis or celiac disease.

CONCLUSION

E1F is a simple, non-invasive, useful tool for the diagnosis of pancreatic insufficiency in children with growth failure or chronic diarrhea, and those with cystic fibrosis. Nevertheless, low values may be found in diseases with villous atrophy or very liquid stools.

Now that fecal elastase is available in the United States, should clinicians start using it?

Fecal elastase-1 estimation is an alternative fecal enzyme test for the detection of exocrine pancreatic insufficiency, which, in contrast to chymotrypsin estimation, uses monoclonal antibodies against human pancreatic elastase and is thus unaffected by simultaneous pancreatic enzyme replacement therapy. Similar to other indirect pancreatic function tests, it has a high sensitivity rate for detecting severe functional impairment of the gland. However, the two major problems for the clinician--namely diagnosing mild to moderate exocrine pancreatic insufficiency or chronic pancreatitis and differentiating pancreatic from nonpancreatic steatorrhea or diarrhea--cannot be solved by pancreatic elastase-1 determination. The test cannot be used in non-formed stool (ie, diarrhea) unless the stool is lyophilized. All in all, this new test does not seem to be the gold standard for pancreatic function that we have been waiting for.

Advances in celiac disease

In recent years, it has become evident that CD is much more common than previously appreciated, with a prevalence of 0.5% to 1% in Western, Arabian, and Indian populations. The disease may be present without symptoms (silent CD) or may present with extraintestinal manifestations only. Increasing awareness of the many faces of CD will increase diagnosis rate. CD patients have a cure for their disease, named the gluten-free diet, but this curative measure is very hard to adhere to. With the new insights into the pathogenesis of CD, clinicians enter an era where new treatment modalities for CD may turn into reality.

Low fecal elastase: potentially related to transient small bowel damage resulting from enteric pathogens

Fecal elastase is considered to be a highly sensitive and specific non-invasive exocrine pancreatic function test. However, enteropathy may theoretically cause decreased exocrine pancreatic enzyme secretion through alteration of enteric hormone release.

OBJECTIVE

The aim of this study was to evaluate the possible influence of transient small bowel damage on pancreatic elastase secretion.

METHODS

We studied 166 children (aged 4 months to 14 years, mean 2 years); 114 of these children had acute enteritis and 52 children were control subjects (with gastro-intestinal symptoms or extra-intestinal diseases). Feces were collected from each patient 3 days after the onset of diarrhea and then tested for fecal elastase, bacterial pathogens, Rotavirus, and Adenovirus. Liquid fecal samples were not considered eligible for elastase measurement. Pancreatic elastase was measured using an ELISA method (Sche.Bo.Tech, Germany). We classified the results, expressed in microg/g stool, as: severe pancreatic insufficiency (<100 microg/g), moderate pancreatic insufficiency (100 to 200 microg/g), and normal (>200 microg/g).

RESULTS

In the acute enteritis group we found severe levels in 14 (12%) children, moderate levels in 18 children (16%), and normal levels in 82 children (72%). In contrast, 52 of 52 (100%) control subjects demonstrated normal results. Statistical analysis (Wilcoxon rank test) demonstrated a significant difference between the enteritis and control groups (P < 0.01). Serial measurement of fecal elastase performed in 10 patients with enteritis showed a progressive increase of levels in 6 patients and an early decline with subsequent increases in the other 4 patients.

CONCLUSIONS

Transient exocrine pancreatic insufficiency may be present in transient small bowel disease, caused by both bacterial and viral infections, possibly related to reduced enteric CCK secretion.

Fecal elastase-1 is superior to fecal chymotrypsin in the assessment of pancreatic involvement in cystic fibrosis

OBJECTIVE

Exocrine pancreatic function in patients with cystic fibrosis (CF) can be evaluated by direct and indirect tests. In pediatric patients, indirect tests are preferred because of their less invasive character, especially in CF patients with respiratory disease. Fecal tests are noninvasive and have been shown to have a high sensitivity and specificity. However, there is no comparative study in CF patients. Therefore, the aim of the present study was to compare the sensitivity and the specificity of the fecal elastase-1 (E1) test with the fecal chymotrypsin (ChT) test in a large cohort of CF patients and healthy subjects (HS).

DESIGN

One hundred twenty-three CF patients and 105 HS were evaluated. In all subjects, E1 concentration and ChT activity were measured. In the CF group, fecal fat excretion was also determined. The sensitivity and specificity of the fecal E1 test and ChT test were compared.

RESULTS

With a cutoff level of 3 U/g, ChT specificity in HS was similar to that of E1, but E1 sensitivity in CF patients was significantly higher (90.2% vs 81.3%). With a cutoff level of 6 U/g, ChT and E1 sensitivity in CF patients was identical, but E1 specificity in HS was again significantly higher (98.1% vs 90.5%). In all CF patients with severe steatorrhea (>15 g/d), E1 concentrations were abnormal and ChT activity was lower than 3 U/g. In contrast, in pancreatic-sufficient patients and patients with mild steatorrhea (< or =15 g/d), the E1 sensitivity was significantly higher compared with ChT (69.2% vs 41.0%).

CONCLUSIONS

The fecal E1 test is superior to fecal ChT determination in the assessment of CF pancreatic involvement in pancreatic-sufficient patients and those patients with mild steatorrhea.

Fecal elastase-1 as a test for pancreatic function: a review

Pancreatic elastase-1 is a specific human protease synthetized by the acinar cells. Immunoreactive elastase-1 cannot be detected in either porcine or bovine pancreatic enzyme preparations. It is very stable and, in contrast to fecal chymotrypsin, elastase is unaffected by exogenous pancreatic enzyme treatment, and correlates well with exocrine pancreatic function tests. The measurement of this proteolytic enzyme in stool by means of an enzyme-linked immunosorbent assay (ELISA) is a sensitive, specific, and relatively inexpensive non-invasive test. It is an accurate function test for patients with chronic pancreatitis confirmed by endoscopic retrograde cholangiopancreatography and computerized axial tomography. It shows higher sensitivity and specificity for exocrine pancreatic insufficiency than fecal chymotrypsin determination and is comparable to oral pancreatic function tests such as the pancreolauryl test.

Faecal elastase 1 concentration is a marker of duodenal enteropathy

BACKGROUND

Measurement of faecal elastase (FE1) is used widely to screen for pancreatic exocrine insufficiency (PI). FE1 does not allow differentiation of primary from secondary PI.

AIMS

To investigate the relation between duodenal morphology and FE1 in children with secondary PI resulting from primary gastrointestinal diseases.

METHODS

A group of 51 children underwent small intestinal biopsy and FE1 measurement. Villus to crypt ratio (VCR) and inflammation within the lamina propria of duodenal mucosal biopsy specimens were scored and compared with FE1 values.

RESULTS

In 51 children from nine diagnostic categories, a highly significant correlation between FE1 and both duodenal morphology and inflammation was found.

CONCLUSION

Small bowel enteropathy is associated with low FE1 concentrations, indicative of secondary exocrine pancreatic insufficiency.

Fecal elastase-1 is decreased in villous atrophy regardless of the underlying disease

BACKGROUND

Fecal elastase-1 (E1) is a sensitive and reliable test in the assessment of exocrine pancreatic function in cystic fibrosis (CF). In patients with celiac disease (CD), different E1 values have been reported. E1 levels in other malabsorption conditions are unknown. Therefore, the aim of the present study was to evaluate E1 concentrations in various malabsorption syndromes.

MATERIAL AND METHODS

The study was carried out in 54 patients, selected from patients referred with suspicion of CF, who had been diagnosed as celiac disease (CD; n = 16), secondary malabsorption syndrome (SMS, giardiasis- or cow milk-related enteropathy; n = 18) and food allergy (FA; n = 20). 70 age-matched healthy children (HC) and 131 cystic fibrosis (CF) patients served as control groups. In CD and SMS patients, a gluten-free diet was introduced. In addition, SMS patients were treated appropriately to underlying disease. In all subjects, E1 concentrations were measured. In CD and SMS patients, E1 concentrations were repeatedly measured after one year of the treatment.

RESULTS

With a cut-off level of 200 microg g-1, abnormal E1 concentrations were found in 87.2% of the CF group and in 56.2% and 50.0% of the CD and SMS subgroups, respectively. In none of FA patients, were E1 values below the normal range. After mucosal recovery, E1 concentrations in patients with CD and SMS increased, suggesting that villous atrophy can diminish exocrine pancreatic secretion. In 18 out of 19 CD and SMS patients with abnormal E1 concentrations, monitored for at least 12 months of a gluten-free diet, abnormal E1 concentrations increased above the cut-off value to normal range. Two out of the 54 referred patients were finally diagnosed as having CF, one with stable low E1 levels and the second with finally normal values.

CONCLUSIONS

The exocrine pancreatic function is decreased in villous atrophy regardless of underlying disease. The specificity of the fecal elastase-1 test in the differentiation between 'primary' exocrine pancreatic insufficiency and intestinal malabsorption with mucosal atrophy is low. After mucosal regeneration, fecal elastase-1 specificity is high.