Are we missing pancreatic exocrine insufficiency in 'at-risk' groups? Prospective assessment of the current practice and yield of faecal elastase testing in patients with diabetes mellitus, HIV and/or high alcohol intake

There is cumulative evidence that pancreatic exocrine insufficiency (PEI) is under-recognised and can occur in patients with 'at-risk' conditions. Thus, we aimed to assess the current practice and yield of requesting faecal elastase (FEL-1), an indicator of PEI, in patients with 'at-risk' conditions. We prospectively recruited patients attending secondary care clinics with diabetes mellitus (DM), people living with HIV (PLHIV) and inpatients admitted to hospital with high alcohol intake (HAI). All patients underwent testing with FEL-1. Those patients with PEI (FEL-1 <200 μg/g) were contacted and offered a follow-up review in gastroenterology clinic. In total, 188 patients were recruited (HAI, n=78; DM, n=64; and PLHIV, n=46). Previous FEL-1 testing had not been performed in any of the patients. The return rate of samples was 67.9% for patients with HAI, 76.6% for those with DM and 56.5% for those with PLHIV. The presence of PEI was shown in 20.4% of patients with DM, 15.4% of patients with PLHIV and 22.6% in those with HAI. Diarrhoea and bloating were the most reported symptoms in followed-up patients with low FEL-1 (31.8% and 22.7% of patients, respectively). Follow-up computed tomography (CT) scans in those patients with PEI identified chronic pancreatitis changes in 13.6% and pancreatic atrophy in 31.8% of patients. These results suggest that there is a lack of testing for PEI in 'at-risk' groups. Our findings also suggest that using FEL-1 to test for PEI in patients with DM, PLHIV and HAI has a significant impact, although further studies are required to validate these findings.

Reduction in abdominal symptoms (CFAbd-Score), faecal M2-pyruvate-kinase and Calprotectin over one year of treatment with Elexacaftor-Tezacaftor-Ivacaftor in people with CF aged ≥12 years - The RECOVER study

BACKGROUND

RECOVER is a multicentre post-approval study of Elexacaftor/Tezacaftor/Ivacaftor (ETI) in pwCF in Ireland and the UK. The CFAbd-Score is the first validated CF-specific patient reported outcome measure (PROM) focusing on gastrointestinal symptoms; it comprises 28 items in 5 domains. In a preliminary study, we previously reported reductions in abdominal symptoms (AS) in pwCF after 26 weeks of ETI-therapy using the CFAbd-Score.

AIM

to assess changes in AS in a second, large cohort and explore novel GI-biomarkers of gut inflammation and cell-proliferation in pwCF over one year of ETI-therapy.

METHODS

Participants were recruited as part of the RECOVER study at 8 sites (Ireland&UK). The CFAbd-Score was administered prior to ETI-initiation, and subsequently at 1,2,6 and 12 months on treatment. Faecal M2-pyruvate kinase (M2-PK) and calprotectin (FC) were quantified in samples collected at baseline, 1 and 6 months.

RESULTS

108 CFAbd-Scores and 73 stool samples were collected at baseline. After 12 months of ETI-therapy, total CFAbd-Scores had significantly declined (15.0±1.4→9.8±1.2pts/p<0.001), and so had all its five domains of "pain" (16.9±2.0pts→9.9±1.8pts/p<0.01), "GERD" (14.4±1.8→9.9±1.6/p<0.05), "disorders of bowel movements" (19.2±1.4→14.1±1.5/p<0.01), "appetite" (7.0±1.1→4.6±1.2/p<0.01) and "impaired-QoL" (13.3±1.9→7.5±1.5/p<0.001). Levels of M2-PK and FC significantly decreased during ETI-therapy.

DISCUSSION

In-depth analysis of AS with the CFAbd-Score reveals a statistically significant, clinically relevant and sustained improvement with ETI. We attribute this to high sensitivity of the implemented CF-specific PROM, developed and validated following FDA-guidelines. Furthermore, for the first time during ETI-therapy a significant decline in faecal M2-PK, a marker of inflammation and cell-proliferation, was found, in parallel to FC.

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

BACKGROUND

¹³C-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 METHODS

This 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.

RESULTS

Overall, 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.

CONCLUSIONS

In 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.

The investigation and management of pancreatic exocrine insufficiency: A retrospective cohort study

Pancreatic exocrine insufficiency (PEI) is associated with significant gastrointestinal symptoms, but is readily treated by pancreatic enzyme replacement therapy (PERT). We reviewed our current practice and examined the factors that predict repeating a positive faecal elastase-1 (FE1; <200 μg/g), the repeat FE1 being normal, initiation of PERT and clinical response to treatment. A single-centre retrospective cohort study was conducted. Outpatients with FE1 <200 μg/g between 2012 and 2018 were included. Logistic regression was used to explore the associations with each outcome, with statistical adjustment for confounders. Two-hundred and ten patients were included; 28.1% of patients had their FE1 repeated, 47.5% of whom had a normal repeat result. Patients with initial FE1 <15 μg/g were unlikely to be reclassified on repeat testing. Patients with a confirmatory low FE1, abnormal pancreatic imaging or abnormal nutrition blood tests were more likely to be started on PERT (all p<0.05). Patients with abnormal pancreatic imaging were 10 times more likely to respond to PERT (odds ratio 10.70; 95% confidence interval 1.62-70.70; p=0.01). Augmenting clinical judgement with pancreatic imaging and repeat FE1 testing could improve the rate of PERT prescription and inform the approach to non-response, particularly in cases where there is diagnostic doubt.

Exocrine pancreatic dysfunction is common in hepatocyte nuclear factor 1β-associated renal disease and can be symptomatic

Background

Heterozygous mutations in the HNF1B gene are the most common monogenic cause of developmental kidney disease. Extrarenal phenotypes frequently occur, including diabetes mellitus and pancreatic hypoplasia; the latter is associated with subclinical exocrine dysfunction. We measured faecal elastase-1 in patients with HNF1B-associated disease regardless of diabetes status and assessed the degree of symptoms associated with pancreatic exocrine deficiency.

Methods

Faecal elastase-1 was measured in 29 patients with a known HNF1B mutation. We defined a low faecal elastase-1 concentration based on the 2.5 percentile of 99 healthy control individuals (410 μg/g stool). Symptoms related to pancreatic exocrine dysfunction were assessed and a subset of the HNF1B cohort (n  =  6) underwent pancreatic imaging.

Results

Faecal elastase-1 was below the 2.5 percentile of the control cohort in 18/29 (62%) patients with HNF1B-associated renal disease. A total of 8/29 (28%) had a measurement suggestive of exocrine pancreatic insufficiency at  <200 μg/g stool; of these, 3 suffered with abdominal pain, loose stools and/or unintentional weight loss. All three experienced symptomatic improvement and weight gain after commencing pancreatic enzyme replacement therapy. Faecal elastase-1 was low in 7/15 (47%) HNF1B patients without diabetes compared with 11/14 (79%) of those with diabetes (P  =  0.1).

Conclusions

Faecal elastase-1 deficiency is a common feature of HNF1B-associated renal disease even when diabetes is not present and pancreatic exocrine deficiency may be more symptomatic than previously suggested. Faecal elastase-1 should be measured in all patients with known HNF1B-associated disease complaining of chronic abdominal pain, loose stools or unintentional weight loss. The discovery of a low faecal elastase-1 concentration in individuals with developmental kidney disease of uncertain cause should prompt referral for HNF1B genetic testing.