Comparison of fecal elastase 1 for exocrine pancreatic insufficiency evaluation between ex-alcoholics and chronic pancreatitis patients

Fat digestion and absorption: Normal physiology and pathophysiology of malabsorption, including diagnostic testing

Fat digestion and absorption play crucial roles in maintaining energy homeostasis and supporting essential physiological functions. The initial stage of fat digestion occurs in the stomach, where gastric lipase begins the hydrolysis of triglycerides. However, most fat digestion takes place in the small intestine via pancreatic enzymes and bile salts. Emulsification of fat by bile acids facilitates enzymatic action, breaking down triglycerides into free fatty acids and monoglycerides, which are then able to be absorbed by enterocytes. Fat malabsorption can result from various underlying conditions, such as exocrine pancreatic insufficiency, bile acid disorders, or intestinal diseases. The clinical manifestations of fat malabsorption include steatorrhea, malnutrition, and deficiencies of fat-soluble vitamins. Diagnostic approaches involve assessing fecal fat levels, imaging studies, and various functional tests to identify the specific etiology. This review article will describe the normal physiologic process of fat digestion and absorption and discuss various pathophysiology that can lead to fat malabsorption within the gastrointestinal tract as well as their respective diagnostic testing modalities. Effective digestion of fat is essential for overall health, because it allows for absorption of many essential nutrients, plays an integral role in cellular and structural function, and supplies energy to the body. When this is dysfunctional, disorders of malabsorption can occur. This article will give a brief overview of the physiologic process of fat digestion and absorption in healthy individuals as well as review important pathophysiology that can lead to fat malabsorption within the gastrointestinal tract and current diagnostic testing modalities.

Two sides of the pancreas: Exocrine insufficiency is correlated with endocrine dysfunction in type 2 diabetes

BACKGROUND

Recently, numerous studies validated frequent pancreatic exocrine dysfunction in patients with diabetes. However, the prevalence of pancreatic exocrine insufficiency (PEI) in diabetes mellitus (DM) varies widely among studies. This study aims to determine the prevalence of PEI in Chinese people with type 2 DM (T2DM) by measuring the fecal elastase-1 (FE-1) levels and further identify potential factors that influence pancreatic exocrine function in patients with T2DM.

METHODS

A total of 85 patients with T2DM without known exocrine pancreatic disorders or digestive system diseases were recruited. Fecal samples were submitted to measure FE-1 levels, and blood samples were collected to investigate pancreatic endocrine function and metabolic biomarkers in all participants. The multiple logistic regression analysis was established to evaluate the influencing factors of PEI in patients with T2DM. The potential predictors of PEI were examined using receiver operating characteristic (ROC) curves.

RESULTS

The prevalence of PEI measured by low FE-1 in T2DM was 18.8%. The Spearman correlation demonstrated that the FE-1 level was inversely correlated with DM duration (r =  - 0.360, P = 0.001) and glycated hemoglobin (HbA1c) level (r =  - 0.228, P = 0.036). A highly significant positive association was observed between FE-1 and fasting C-peptide (FCP) levels (r = 0.451, P < 0.001). Furthermore, the multiple logistic regression analysis showed that FCP was an independent influencing factor of PEI (OR = 0.204, P = 0.024, 95% CI: 0.051-0.813). The ROC analysis indicated that the FCP level had a predictive value for low FE-1 (AUC = 0.793, P < 0.001) with an optimal cutoff value of 1.20 ng/ml.

CONCLUSION

Chinese patients with T2DM show high PEI prevalence. FCP may be a potential predictor of pathological exocrine function in T2DM. The exocrine and endocrine functions of patients with T2DM in clinical practice should be evaluated. Further studies are needed to clarify the internal association between exocrine and endocrine pancreases.

Analytically validated protein biomarkers of chronic pancreatitis and pancreatic cancer for potential clinical diagnosis with mass spectrometry

RATIONALE

Chronic pancreatitis (CP) is a pancreatic disease with poor prognosis and pancreatic cancer (PC) is one of the most lethal types of cancer that is symptomless in the early stage. Because the clinical and image findings of CP can overlap that of pancreatic cancer (PC) which leads to confusion in the diagnosis and treatment of PC, discovery/verification/validation of more accurate protein biomarkers to diagnose CP and PC is in urgent need.

METHODS

The PubMed, Web of Science, and Google Scholar were searched using the keywords: 'biomarker', 'marker', 'chronic pancreatitis', "pancreatic cancer" or "proteomics" for highly related researches. We focused on the articles published after the year 2005 in this review.

RESULTS

We introduce the background to CP and PC and summarize the diagnosis of CP and PC, analytically validated protein biomarkers, and proteomic approaches for discovery/verification/validation. The potential use of mass spectrometry (MS) in clinical diagnosis is also discussed.

CONCLUSIONS

Continuously improving sensitivity of MS can provide deeper proteome for new marker discovery and high reliability for protein marker verification, validation, and clinical diagnosis. The analytically validated protein markers could be considered as targeted protein biomarkers for developing a MS platform in the clinical validation process or clinical diagnosis of CP and PC.

Diagnostic Performance of Measurement of Fecal Elastase-1 in Detection of Exocrine Pancreatic Insufficiency: Systematic Review and Meta-analysis

BACKGROUND & AIMS

Tests to quantify fecal levels of chymotrypsin like elastase family member 3 (CELA3 or elastase-1) in feces are widely used to identify patients with exocrine pancreatic insufficiency (EPI). However, the diagnostic accuracy of this test, an ELISA, is not clear. We performed a systematic review and meta-analysis to determine the accuracy of measurement of fecal elastase-1 in detection of EPI.

METHODS

We searched PubMed, Embase, and reference lists for articles through November 2016 describing studies that compared fecal level of elastase-1 with results from a reference standard, direct method (secretin stimulation test), or indirect method (measurement of fecal fat) for detection of EPI. Sensitivity and specificity values were pooled statistically using bivariate diagnostic meta-analysis.

RESULTS

We included total of 428 cases of EPI and 673 individuals without EPI (controls), from 14 studies, in the meta-analysis. The assay for elastase-1, compared to secretin stimulation test, identified patients with pancreatic insufficiency with a pooled sensitivity value of 0.77 (95% CI, 0.58-0.89) and specificity value of 0.88 (95% CI, 0.78-0.93). In an analysis of 345 cases of EPI and 312 controls, from 6 studies, the fecal elastase-1 assay identified patients with EPI with a pooled sensitivity value of 0.96 (95% CI, 0.79-0.99) and specificity value of 0.88 (95% CI, 0.59-0.97), compared to quantitative fecal fat estimation. In patients with low pre-test probability of EPI (5%), the fecal elastase-1 assay would have a false-negative rate of 1.1% and a false-positive rate of 11%, indicating a high yield in ruling out EPI but not in detection of EPI. In contrast, in patients with high pre-test probability of EPI (40%), approximately 10% of patients with EPI would be missed (false negatives).

CONCLUSIONS

In a systematic review and meta-analysis of studies that compared fecal level of elastase-1 for detection of EPI, we found that normal level of elastase-1 (above 200 mcg/g) can rule out EPI in patients with a low probability of this disorder (such as those with irritable bowel syndrome with diarrhea). However, in these patients, an abnormal level of elastase-1 (below 200 mcg/g) has a high false-positive rate.

Pancreatic exocrine insufficiency following acute pancreatitis: Systematic review and study level meta-analysis

OBJECTIVES

This study systematically explores the prevalence of pancreatic exocrine insufficiency (PEI) after acute pancreatitis in different subgroups of etiology (biliary/alcoholic/other), disease severity and follow-up time (<12, 12-36 and > 36 months after index admission).

METHODS

PubMed and EMBASE databases were searched, 32 studies were included in this study level meta-analysis.

RESULTS

In a total of 1495 patients with acute pancreatitis, tested at a mean of 36 months after index admission, the pooled prevalence of PEI was 27.1% (95%-confidence interval [CI]: 20.3%-35.1%). Patients from seven studies (n = 194) underwent direct tests with pooled prevalence of 41.7% [18.5%-69.2%]. Patients from 26 studies (n = 1305) underwent indirect tests with pooled prevalence of 24.4% [18.3%-31.8%]. In subgroup analyses on patients that underwent fecal elastase-1 tests, PEI occurred more often in alcoholic pancreatitis (22.7% [16.6%-30.1%]) than in biliary pancreatitis (10.2% [6.2%-16.4%]) or other etiology (13.4% [7.7%-22.4%]; P = 0.02). Pooled prevalence of PEI after mild and severe pancreatitis was 19.4% [8.6%-38.2%] and 33.4% [22.6%-46.3%] respectively in studies using fecal elaste-1 tests (P = 0.049). Similar results were seen in patients without (18.9% [9.3%-34.6%]) and with necrotizing pancreatitis (32.0% [18.2%-49.8%]; P = 0.053). Over time, the prevalence of PEI decreased in patients who underwent the fecal elastase-1 test and increased in patients who underwent the fecal fat analysis.

CONCLUSIONS

After acute pancreatitis, a quarter of all patients develop PEI during follow-up. Alcoholic etiology and severe and necrotizing pancreatitis are associated with higher risk of PEI. The prevalence of PEI may change as time of follow-up increases.

Preoperative fecal elastase-1 is a useful prognostic marker following curative resection of pancreatic cancer

BACKGROUND

The clinical relevance of fibrosis with regard to tumor progression is supported by the correlation between fibrosis and poor outcomes. Fecal elastase-1 (FE-1) level has been used to assess exocrine dysfunction of the pancreas and to predict pancreas fibrosis. The aim of this study was to assess the impact of FE-1 on the survival of pancreatic cancer patients.

METHODS

Between January 2006 and December 2014, 136 patients with pancreatic adenocarcinoma underwent R0 resection at Gangnam Severance Hospital, Korea. Preoperative FE-1 levels were available in 94 patients who were enrolled in the study. Patients were classified into two groups according to preoperative FE-1: "normal" (≥200 μg/g) or "reduced" (<200 μg/g).

RESULTS

Median preoperative FE-1 level was 130.1 μg/g (IQR 32.0; 238.3). 62 patients (66.0%) had reduced pancreatic function and 32 patients (34.0%) had normal pancreatic function. The two groups had significantly different disease-free survival (P < 0.001). On multivariate analysis, normal FE-1, no lymph node metastasis and completion of adjuvant chemotherapy were found to be independent prognostic factors for better DFS (P = 0.001, P = 0.017, P = 0.038, respectively).

CONCLUSION

FE-1 is a simple and non-invasive predictive clinical marker for prognosis of pancreatic cancer after attempted curative resection.

Pancreatic Elastase Levels in Feces As A Marker of Exocrine Pancreatic Function in Patients With Diabetes Mellitus

OBJECTIVE

The measurement of pancreatic elastase (PE) in feces is used widely to screen for pancreatic exocrine insufficiency. The aim of our study was to evaluate the relationship of PE with residual beta cell secretion and metabolic control in patients with diabetes mellitus.

METHOD

We determined the presence of PE in specimens via enzyme-linked immunosorbent assay (ELISA), whereas serum fasting glucose, C-peptide, amylase, lipase, triglycerides, total 25(OH)-vitamin D, C-reactive protein (CRP), and hemoglobin A1c (HbA1c) concentrations were assayed using routine laboratory tests.

RESULTS

PE values in 48 patients with diabetes were significantly lower than in 24 healthy volunteers (P = 001). In one-third of participants with diabetes mellitus, PE were less than 200 µg per g, indicating pancreatic functional insufficiency. Among the patients in the cohort, PE correlated positively with C-peptide levels (P = 04), lipase (P = 009), CRP (P = 04), sex (P = 03), and BMI (P = 02) but not significantly with duration of diabetes (P = 81) or levels of HbA1c(P = 87), amylase (P = 06), total 25(OH)-vitamin D (P = 16), or triglycerides (P = 52).

CONCLUSION

Our results demonstrated a strong association of diabetes with low PE levels.