Fecal Chymotrypsin Research Articles

Abbreviated 13C-mixed triglyceride breath test for detection of pancreatic exocrine insufficiency performs equally as standard 5-hour test in patients after gastrectomy performed for gastric cancer.

Background13C-mixed triglyceride breath test (13C-MTGT) is a non-invasive test for the detection of moderate and severe pancreatic exocrine insufficiency (PEI), but it requires prolonged breath sampling. The aim of this study was to determine the diagnostic power of abbreviated 13C-MTGT in detecting PEI in patients after subtotal and total gastrectomy performed due to gastric cancer.Subjects and methodsThis cross-sectional observational study included 3 groups of subjects; healthy controls, patients with subtotal and patients with total gastrectomy. Demographic and clinical data of patients were collected. Stool samples to determine faecal elastase (Fe-1) and chymotrypsin were collected and measured by ELISA. All subjects performed 5-hour 13C-MTGT breath test. The concentration and relative content of 13C in exhaled air was measured by isotope ratio mass spectrometer (IRMS). PEI was confirmed as values of 13C-exhalation < 26.8% after 5 hours.ResultsOverall, 65 participants were included into analysis, 22 having PEI (n = 11 after subtotal and n = 11 after total gastrectomy, both performed for gastric cancer). 13C-MTGT breath test showed difference in percent of exhaled 13C between PEI and non-PEI patients already after 60 minutes (p = 0.034). Receiver operating characteristic (ROC) curve analysis showed that cut-off value of 13.74% after 150 minutes is showing equivalent diagnostic power to the longer test with sensitivity and specificity both above 90% for the exclusion of PEI in patients after subtotal and/or total gastrectomy.ConclusionsIn this study abbreviated 13C-MTGT test could be shortened from 5 to 2.5 hours without decrease in its diagnostic accuracy for detection of PEI in patients with subtotal or total gastrectomy performed for gastric cancer. This allows significant time savings in the diagnostics of PEI in this subgroup of patients.

Pancreatitis severity in mice with impaired CFTR function but pancreatic sufficiency is mediated via ductal and inflammatory cells-Not acinar cells.

Mutations in the cystic fibrosis transmembrane conductance regulator gene (CFTR) are an established risk factor for cystic fibrosis (CF) and chronic pancreatitis. Whereas patients with CF usually develop complete exocrine pancreatic insufficiency, pancreatitis patients with CFTR mutations have mostly preserved exocrine pancreatic function. We therefore used a strain of transgenic mice with significant residual CFTR function (CFTRtm1HGU) to induce pancreatitis experimentally by serial caerulein injections. Protease activation and necrosis were investigated in isolated acini, disease severity over 24h, pancreatic function by MRI, isolated duct stimulation and faecal chymotrypsin, and leucocyte function by ex vivo lipopolysaccharide (LPS) stimulation. Pancreatic and lung injury were more severe in CFTRtm1HGU but intrapancreatic trypsin and serum enzyme activities higher than in wild‐type controls only at 8h, a time interval previously attributed to leucocyte infiltration. CCK‐induced trypsin activation and necrosis in acini from CFTRtm1HGU did not differ from controls. Fluid and bicarbonate secretion were greatly impaired, whereas faecal chymotrypsin remained unchanged. LPS stimulation of splenocytes from CFTRtm1HGU resulted in increased INF‐γ and IL‐6, but decreased IL‐10 secretion. CFTR mutations that preserve residual pancreatic function significantly increase the severity of experimental pancreatitis—mostly via impairing duct cell function and a shift towards a pro‐inflammatory phenotype, not by rendering acinar cells more susceptible to pathological stimuli.

Long term follow-up of a simplified and less burdened pancreatic duct ligation model of exocrine pancreatic insufficiency in Goettingen Minipigs

BackgroundPancreatic duct ligation in a minipig model leads to exocrine pancreatic insufficiency (EPI). This allows the study of digestive processes and pancreatic enzyme replacement therapies. However, detailed descriptions of the surgical procedure, perioperative management, a determination of exocrine pancreatic insufficiency are scarce in the literature. Data of the long-term health status of minipigs upon EPI induction are still not available. Therefore, the present study describes in detail an experimental approach to the induction of exocrine pancreatic insufficiency via pancreatic duct ligation in minipigs and the long term follow up of the animal’s health state.Methods14 Goettingen minipigs underwent pancreatic duct ligation via midline laparotomy for the induction of exocrine pancreatic insufficiency. Fecal fat content, fat absorption, chymotrypsin levels, body weight and blood vitamin and glucose levels were determined.ResultsExocrine pancreatic insufficiency was successfully induced in 12 Goettingen minipigs. Two minipigs failed to develop exocrine insufficiency most likely due to undetected accessory pancreatic ducts. All animals tolerated the procedure very well and gained weight within 8 weeks after surgery without requiring pancreatic enzyme replacement therapy. The follow up for approx. 180 weeks showed a stable body weight and health state of the animals with normal blood glucose levels (Table 1). From approx. 130 weeks post pancreatic duct ligation, all animals were supplemented with pancreatic enzymes and vitamins resulting in blood concentrations almost within the reference range.ConclusionsPancreatic duct ligation in minipigs is an excellent method of inducing exocrine pancreatic insufficiency. It is important to identify and ligate accessory pancreatic ducts since persistence of accessory ducts will lead to maintenance of exocrine pancreatic function. The EPI model caused no persistent side effects in the animals and has the potential to be used in long-term EPI studies with up to 100 weeks post-OP without supplementation with enzymes and vitamins.

Nutritional markers in patients with diabetes and pancreatic exocrine failure

Altered pancreatic exocrine function can be observed in patients with type 1 or type 2 diabetes. In the present study, we evaluated the potential nutritional consequences of this dysfunction. Serum concentrations of nutritional markers, including albumin, cholesterol, triacylglycerol, vitamins A, D, and E, were assessed in a cohort of 468 patients (137 with type 1 diabetes and 331 with type 2 diabetes), after exclusion of the patients with a CRP > 10mg/l. These patients were compared with 47 patients with diseases of the exocrine pancreas and diabetes (type 3c diabetes or pancreatogenic diabetes). Fecal elastase-1 and chymotrypsin concentrations were measured and patients with type 1 and type 2 diabetes were divided into three groups according to whether zero (group NN), one (group LN), or both (group LL) concentrations were decreased. Several markers differed significantly between the groups of patients, including BMI, albumin, phosphorus, and fat-soluble vitamins. Patients with pancreatogenic diabetes had markedly more profound alterations than patients with type 1 or type 2 diabetes and altered exocrine function. However, patients with type 1 or type 2 diabetes and decreased concentrations of both elastase-1 and chymotrypsin had lower albumin, phosphorus, and vitamin A than patients with normal pancreatic exocrine function. Modest nutritional alterations were found in patients with type 1 or type 2 diabetes and altered exocrine function. Patients with type 1 or type 2 diabetes and altered exocrine function may thus deserve to be screened for nutritional deficiencies.

Unconjugated bilirubin ameliorates the inflammation and digestive protease increase in TNBS-induced colitis.

The authors previously demonstrated that unconjugated bilirubin (UCB) may inhibit the activities of various digestive proteases, including trypsin and chymotrypsin. The digestive proteases in the lower gut are important in the pathogenesis of inflammatory bowel diseases. The effects of UCB on the inflammation and levels of digestive proteases in feces of rats with colitis have not yet been revealed. The present study investigated the effect of UCB on the inflammatory status and levels of trypsin and chymotrypsin in the feces of rats with trinitrobenzenesulfonic acid (TNBS)-induced colitis. The data indicated that treatment with TNBS resulted in a marked reduction in weight gain, which was significantly alleviated in UCB-treated rats. Furthermore, UCB treatment alleviated the inflammation induced by TNBS, detected via macroscopic damage and microscopic inflammation scores, and pro-inflammatory markers including myeloperoxidase (MPO), tumor necrosis factor (TNF)-α and interleukin (IL)-1β. Furthermore, rats with colitis demonstrated significant increases in fecal trypsin and chymotrypsin levels, whereas UCB treatment significantly alleviated these increases. A significant positive correlation was additionally revealed among the pro-inflammatory markers (MPO, TNF-α and IL-1β) and fecal digestive proteases (trypsin and chymotrypsin) in colitis. The results of the present study demonstrated that UCB ameliorated the inflammation and digestive protease increase in TNBS-induced colitis.

The CTRB1/2 Locus Affects Diabetes Susceptibility and Treatment via the Incretin Pathway

The incretin hormone glucagon-like peptide 1 (GLP-1) promotes glucose homeostasis and enhances β-cell function. GLP-1 receptor agonists (GLP-1 RAs) and dipeptidyl peptidase-4 (DPP-4) inhibitors, which inhibit the physiological inactivation of endogenous GLP-1, are used for the treatment of type 2 diabetes. Using the Metabochip, we identified three novel genetic loci with large effects (30–40%) on GLP-1–stimulated insulin secretion during hyperglycemic clamps in nondiabetic Caucasian individuals (TMEM114; CHST3 and CTRB1/2; n = 232; all P ≤ 8.8 × 10−7). rs7202877 near CTRB1/2, a known diabetes risk locus, also associated with an absolute 0.51 ± 0.16% (5.6 ± 1.7 mmol/mol) lower A1C response to DPP-4 inhibitor treatment in G-allele carriers, but there was no effect on GLP-1 RA treatment in type 2 diabetic patients (n = 527). Furthermore, in pancreatic tissue, we show that rs7202877 acts as expression quantitative trait locus for CTRB1 and CTRB2, encoding chymotrypsinogen, and increases fecal chymotrypsin activity in healthy carriers. Chymotrypsin is one of the most abundant digestive enzymes in the gut where it cleaves food proteins into smaller peptide fragments. Our data identify chymotrypsin in the regulation of the incretin pathway, development of diabetes, and response to DPP-4 inhibitor treatment.

Shwachman-Diamond syndrome: a complex case demonstrating the potential for misdiagnosis as asphyxiating thoracic dystrophy (Jeune syndrome)

BackgroundThe differential diagnosis of a neonate or fetus presenting with a bell-shaped or long narrow thorax includes a wide range of bony dysplasia syndromes. Where this is accompanied by respiratory distress, asphyxiating thoracic dystrophy (ATD, Jeune syndrome) is an important potential diagnosis. Shwachman-Diamond syndrome (SDS) is widely recognised as a cause of exocrine pancreatic dysfunction, short stature and bone marrow failure. It is not so well appreciated that rib and/or thoracic cage abnormalities occur in 30–50% of patients and that, in severe cases, these abnormalities may lead to thoracic dystrophy and respiratory failure in the newborn. There are, however, at least three previous case reports of children who were initially diagnosed with ATD who were subsequently shown to have SDS.Case presentationThis report details the case history of a patient misdiagnosed as having ATD as a neonate following the neonatal asphyxial death of her brother. She subsequently developed progressive pancytopenia but was only diagnosed with SDS at 11 years of age after referral for haematopoietic stem cell transplantation for bone marrow failure accompanied by trilineage dysplasia and clonal cytogenetic abnormalities on bone marrow examination. Subsequent testing revealed the presence of fat globules in stools, reduced faecal chymotrypsin, fat-soluble vitamin deficiency, metaphyseal dysplasia on skeletal survey and heterozygous mutations of the SBDS gene.ConclusionThis report highlights the potential for diagnostic confusion between ATD and SDS. It is important to include SDS in the differential diagnosis of newborns with thoracic dystrophy and to seek expert clinical and radiological assessment of such children.

Indicación e interpretación de las pruebas funcionales pancreáticas

Pancreatic function tests have been used over decades for the diagnosis of chronic pancreatitis and the evaluation of exocrine pancreatic function in patients with known pancreatic disease. At present, only the endoscopy-based pancreatic function test and the magnetic resonance cholangiopancreatography after intravenous injection of secretin play a relevant role in the diagnosis of early chronic pancreatitis. Methods as the coefficient of fat absorption and the 13C-triglyceride breath test are mainly indicated for the diagnosis of pancreatic exocrine insufficiency and the evaluation of the efficacy of the pancreatic enzyme replacement therapy. Fecal elastase-1 quantification is still useful as an initial test in patients with clinical suspicion of chronic pancreatitis, whereas the use of fecal chymotrypsin is limited to the objective evaluation of patient's compliance to pancreatic enzyme replacement therapy.

Adaptive changes of pancreatic protease secretion to a short-term vegan diet: influence of reduced intake and modification of protein

In our previous study, we demonstrated that abstaining from meat, for 1 month, by healthy omnivores (lacto-ovovegetarian model) resulted in a statistical decrease in pancreatic secretion as measured by faecal elastase-1 output. However, no correlation between relative and non-relative changes of energy and nutrient consumption and pancreatic secretion was documented. Therefore, in the present study, we aimed to assess the changes of exocrine pancreatic secretion with a more restrictive dietetic modification, by applying a vegan diet. A total of twenty-one healthy omnivores (sixteen females and five males) participated in the prospective study lasting for 6 weeks. The nutrient intake and faecal output of pancreatic enzymes (elastase-1, chymotrypsin and lipase) were assessed twice during the study. Each assessment period lasted for 7d: the first before the transition to the vegan diet (omnivore diet) and the second during the last week of the study (vegan diet). The dietary modification resulted in a significant decrease in faecal elastase-1 (P<0·05) and chymotrypsin output (P<0·04). The lipase excretion remained unchanged. The decrease in proteolytic enzymes was documented to be positively correlated with a decreased protein intake (P<0·05). In addition, elastase-1 and chymotrypsin outputs were also related to the changes of protein type, plant v. animal (P<0·04 and P<0·03, respectively). It was concluded that significant reduction and modification of protein intake due to a short-term vegan diet resulted in an adaptation of pancreatic protease secretion in healthy volunteers.

Pancreatic Volume and Endocrine and Exocrine Functions in Patients With Diabetes

Exocrine function has been described in patients with diabetes. We hypothetized that patients with exocrine dysfunction have pancreatic atrophy. This is a cohort study of hospitalized patients. Thirty-five patients were selected after detection of impaired exocrine function in routine tests, and 17 patients were matched for age and body mass index to the previous cohort. The pancreatic volume was evaluated on sections of computed tomographic scans of the pancreas. Other investigations included a glucagon stimulation test and determination of fecal elastase-1 concentration and chymotrypsin activity. Fifty-two patients participated in this study, 24 with type 1 diabetes and 28 with type 2 diabetes. Duration of diabetes was 15 years (5-26 years; median [interquartile range]). The pancreatic volume, 42 cm (25-57 cm), was decreased in most patients. It did not differ in patients with type 1 diabetes compared with those with type 2 diabetes. It was decreased in patients treated with insulin and in those with low elastase-1 concentration or low chymotrypsin activity. In the multiple linear regression analysis, the pancreatic volume correlated with chymotrypsin activity and stimulated C-peptide. We have unraveled a link between 2 old observations in patients with diabetes: atrophy of the pancreas and exocrine deficiency. These observations give credence to the reality of the exocrine dysfunction in patients with diabetes.

Asian chronic pancreatitis: The common and the unique

Chronic pancreatitis (CP) is a disabling condition worldwide that presents as pain, maldigestion, and diabetes. It is usually perceived as alcohol related, or classified as idiopathic otherwise. However, this is true only for Western countries. Asian CP comprises not only alcohol-related CP but also tropical pancreatitis (TP). Tropical pancreatitis is a unique entity commonly found in South Asia. It shares similar presentations with other CPs for pain and maldigestion. However, its diabetes is more ketosis resistant. Non-surgical approach like endoscopic therapy plus extracoporeal shock wave lithotripsy provides better outcome for TP than other CPs, because of its less strictured pancreatic duct that is more amenable to endoscopic stone clearance. Diagnosis of CP in Asia mainly relies on image studies such as ultrasonography ± computed tomography (CT) scan, and non-invasive tests on fecal chymotrypsin, serum trypsin, and serum pancreatic isoamylase. Endoscopic ultrasonography and intestinal tubing tests are used mainly in some research centers. Autoimmune pancreatitis (AIP) is another CP originated from Asia in large series and subsequently being recognized in the West. AIP patients seldom present with maldigestion until the disease progresses to a very late stage and this occurs in less than one third of patients. In contrast, AIP is usually presented as pseudotumor of the pancreatic head, causing obstructive jaundice. Immunoglobulin G4 level is typically elevated in AIP and can be used as a marker for responsiveness. Without a need of surgery, steroids are the standard treatment. Those who relapse and are resistant to steroids should be placed on long-term immunosuppressive agents.

Exocrine Pancreatic Dysfunction

Exocrine pancreas dysfunction is a potential basis for accurate diagnosis of chronic pancreatitis. However, the dysfunction evaluated with various diagnostic tools is not necessarily specific for chronic pancreatitis. At present, the secretin test as a duodenal intubation test and the fecal chymotrypsin activity assay are difficult to apply in clinics in Japan. Now, the BT-PABA test is the only one available for examination of the exocrine pancreatic function. The clinical meaning of the test has been well established and it is a noninvasive. However, reproducibility based on exclusion of the influence of PABA metabolism in vivo is necessary for the estimation of the test. The diagnosis of exocrine dysfunction is allowed by several apparent decreases in the results of BT-PABA test. The mainstream clinical diagnosis for the earlier phase of chronic pancreatitis is based on imaging diagnostic procedures that show histological changes of the pancreas. In the revised criteria, exocrine pancreatic dysfunction is one of the six diagnostic characteristics of chronic pancreatitis.

Diagnosis of chronic pancreatitis: Functional testing

The diagnosis of chronic pancreatitis is mainly based on imaging procedures (e.g., endoscopic ultrasound, magnetic resonance cholangiopancreatography (MRCP) and magnetic resonance imaging (MRI)). Functional testing in this context could however be still of help in cases of inconclusive morphological findings. With this aim, only the secretin-pancreozymin test and the endoscopic test are sensitive enough. The role of other function tests, such as the quantification of the coefficient of fat absorption (CFA) and the (13)C-mixed triglyceride breath test, is limited to the diagnosis of exocrine pancreatic insufficiency with maldigestion. Faecal elastase and chymotrypsin are still useful for detecting reduction of pancreatic secretion in patients with different pancreatic diseases and patients' compliance to enzyme replacement therapy, respectively. Other tests used in the past (e.g., Lundh test, N-benzoyl-tryosyl para-aminobenzoic acid (NBT-PABA) test, pancreolauryl test and amino acid consumption test) are neither available now nor useful for clinical practice. This article reviews the different pancreatic function tests commercially available and their role in clinical practice.

Persistent elevated tissue‐transglutaminase in cystic fibrosis

Persistent elevated tissue‐transglutaminase in cystic fibrosis

Estimation of postoperative fat absorption using the 13C mixed-triglyceride breath test in children with choledochal cyst

No previous studies have focused on postoperative fat malabsorption in children with choledochal cyst (CC) who undergo cyst excision and Roux-en-Y (RY) hepatico-jejunostomy (HJ), a combination of procedures that can lead to the non-physiological mixture of food and bile juice. To examine the effect of RYHJ with cholecystectomy on the fat absorption ability of children with CC, we estimated postoperative fat-absorption ability using the carbon 13-labeled mixed triglyceride (13C-MTG) breath test. Twelve postoperative children with CC and 12 normal control children were administered 13C-MTG orally and asked to give breath samples at six time points: once before the 13C-MTG ingestion and at five 60-min intervals postingestion. Fecal chymotrypsin activity and fecal fat excretion were also measured. The delta value of breath 13CO2 at 3, 4, and 5 h after administration and the 5-h cumulative breath 13CO2 were significantly lower in the CC children than in the controls. There were no significant differences in the fecal chymotrypsin activity or fecal fat excretion of the two groups. Conclusion. Occult fat malabsorption occurs in patients with CC after RYHJ, even in the absence of clinical symptoms or abnormal laboratory data.

Digestive function of the residual pancreas after partial duodenopancreatectomy for chronic pancreatitis (author's transl)

Forty-eight patients with chronic recurrent pancreatitis treated by resection of the head of the pancreas were restudied more than a year post-operatively. In addition to general features such as symptoms, alcohol consumption and work ability, faecal weight, its fat content, fat and fatty acid balance and faecal chymotrypsin were measured. According to the patients' own estimate, late results were good or very good in 70-90%. Faecal fat content and balance indicated high-grade exocrine pancreatic insufficiency in 80 and 90%, respectively. But it was easily controlled by drugs. In a third of the cases there was the need to supplement the diet with medium-chain triglycerides. Its components are satisfactorily absorbed even when the fat utilisation is severely abnormal.

Resection vs Drainage in Treatment of Chronic Pancreatitis: Long-term Results of a Randomized Trial

Tailored organ-sparing procedures have been shown to alleviate pain and are potentially superior in terms of preservation of endocrine and exocrine function as compared with standard resection (Whipple) for chronic pancreatitis with inflammatory pancreatic head tumor. Long-term results comparing these 2 procedures have not been published so far. The aim of this study was to report on long-term results of a randomized trial comparing a classical resective procedure (pylorus-preserving Whipple) with an extended drainage procedure (Frey) for chronic pancreatitis. All patients who participated in a previously published randomized trial on the perioperative course comparing both procedures were contacted with a standardized, validated, quality of life and pain questionnaire. Additionally, patients were seen in the outpatient clinic to assess endocrine and exocrine pancreatic function by an oral glucose tolerance test and fecal chymotrypsin test. There were no differences between both groups regarding quality of life, pain control, or other somatic parameters after a median of 7 years postoperatively. Correlations among continuous alcohol consumption, endocrine or exocrine pancreatic function, and pain were not found. Both procedures provide adequate pain relief and quality of life after long-term follow-up with no differences regarding exocrine and endocrine function. However, short-term results favor the organ-sparing procedure.

Dietary Counseling Versus Dietary Supplements for Malnutrition in Chronic Pancreatitis: A Randomized Controlled Trial

Up to 50% of patients with chronic pancreatitis (CP) are malnourished. There are limited data on the role of dietary intervention in improving the nutritional status of such patients. The aim was to compare the efficacy of medium chain triglyceride (MCT)-enriched commercial dietary supplements with dietary counseling for homemade food in the management of malnutrition in patients with CP. In a randomized controlled trial, consecutive undernourished patients with CP (body mass index [BMI] <18.5 kg/m(2)) at a tertiary care hospital were randomized to receive either dietary counseling for regular homemade food or commercial MCT-enriched dietary supplements for a period of 3 months to compensate for the dietary calorie deficit. All patients received standard management for CP including pancreatic enzyme supplements. Primary outcome measure was improvement in BMI. Sixty malnourished patients with CP were randomized to counseling group (n = 29; mean age, 32 +/- 10 years; male, 83%) and supplementation group (n = 31; mean age, 28 +/- 10 years; male, 84%). BMI increased in both the counseling group and supplementation group (17.2 +/- 1.7 vs 18.1 +/- 1.8 kg/m(2), P = .001; 16.7 +/- 1.6 vs 18.2 +/- 1.6 kg/m(2), P = .001). There were similar improvements in triceps skinfold thickness, dietary intake, fecal fat, and pain score during a period of 3 months in both groups. There was, however, no significant difference between the counseling and supplementation groups with regard to any of the outcome measures. Dietary counseling for a balanced homemade diet is as good as commercial food supplements in improving malnutrition in patients with CP.

Intrauterine growth restriction, visceral blood flow velocity and exocrine pancreatic function

BackgroundAnimal models and observations in human neonates suggest fetal exocrine pancreas vulnerability to reduced maternofetal blood flow. We investigated the relationship between superior mesenteric artery blood flow velocity (sma bfv) and exocrine pancreatic function, in a cohort of very low birth weight (VLBW) babies.Group 1: 9 babies < 3rd percentile for birth weight. Antenatally, all had absent or reversed diastolic flow on Doppler ultrasound of the umbilical artery (UA).Group2: 18 babies > 10th percentile for birth weight.FindingsAll had Doppler ultrasound scan of the superior mesenteric artery (sma), by same operator (RMN), on day 1 of life before commencement of enteral feeding. Stool samples assayed for faecal chymotrypsin and weekly serum samples assayed for amylase and lipase (kinetic colorimetric assay) from days 1 to 14 of life.Growth restricted babies had significantly lower sma bfv values compared with appropriately grown preterm babies. Faecal chymotrypsin levels were also lower but this difference did not achieve statistical significance. Both groups had serum lipase levels detectable in adult concentrations. Serum amylase was undetectable in either group.ConclusionBabies with previous in-utero blood flow redistribution may exhibit altered gut ontogeny with re-setting of mesenteric blood flow velocities and altered exocrine pancreatic function.

Pancreatic function testing: here to stay for the 21st century.

The diagnosis of Chronic Pancreatitis (CP) is based on the detection of abnormal structure or function of the diseased pancreas. The pancreatic function tests more accurately determine the presence of CP than tests of structure, especially for early stage disease. The function tests can be divided into two categories: non-invasive and invasive. The invasive "tube" tests can reliably detect mild, early CP, but are only available at a few referral centers and tend to be poorly tolerated by patients. The non-invasive tests are easy to obtain, but tend to perform poorly in patients with early, mild disease. Therefore, no one test is useful in all clinical situations, and a detailed understanding of the rational, pathophysiologic basis, strengths, and limitations of various tests is needed. This review highlights the role of various pancreatic function tests in the diagnosis of CP including fecal fat analysis, fecal elastase, fecal chymotrypsin, serum trypsin, the secretin stimulation test, the cholecystokinin (CCK) stimulation test, the combined secretin-CCK stimulation test, the intraductal and endoscopic secretin stimulation tests, and the functional magnetic resonance imaging of the pancreas after secretin stimulation.