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

BACKGROUND: Exocrine pancreatic insufficiency (EPI) can be associated with all types of diabetes. Pancreatic enzyme replacement therapy (PERT) has short and long-term benefits in subjects with EPI, but its effects on diabetes control are uncertain. We aimed to study the effects of PERT initiation on glycemic control in subjects with diabetes and EPI from any cause.
METHODS: In this retrospective study, we compared subjects with EPI and diabetes who were prescribed PERT with subjects with diabetes who had a fecal elastase-1 concentration dosage, but did not receive PERT. The primary outcome was the effect of PERT on hypoglycemia frequency and severity. The secondary outcomes were the effects of PERT on gastro-intestinal disorders, HbA1c and body mass index (BMI).
RESULTS: 48 subjects were included in each group. Overall, PERT did not have any significant effect on hypoglycemia frequency or severity, but hypoglycemia frequency tended to decrease in subjects with chronic pancreatitis. While 19% of subjects experienced mild hyperglycemia after PERT initiation, we did not report any keto-acidosis or any other severe adverse event. Gastro-intestinal disorders improved in 80% of subjects treated with PERT, versus in 20% of control subjects (p = 0.02). Gastro-intestinal disorders improved in 87% of subjects with recommended dosage of PERT, versus in 50% of subjects with underdosage (NS). HbA1c and BMI evolution did not differ between the groups.
CONCLUSIONS: PERT initiation is safe in subjects with diabetes and EPI. It does not globally decrease hypoglycemia severity of frequency, but is associated with a decrease in gastro-intestinal disorders. Trial registration Retrospectively registered. The database was registered with the Commission Nationale Informatique et Libertés (CNIL), registration number: 2203351v0. The study was approved by the local ethics committee CLEP, registration number: AAA-2023-09047.

OBJECTIVE: Studies of a rare homozygous missense mutation identified in two brothers diagnosed with congenital pancreatic lipase deficiency (CPLD) provided the first definitive evidence linking CPLD with missense mutations in the gene of PNLIP. Herein, we investigated the molecular basis for the loss-of-function in the three novel PNLIP variants (c.305G > A, p.(W102∗); c.562C > T, p.(R188C); and c.1257G > A, p.(W419∗)) associated with CPLD.
METHODS: We characterized three novel PNLIP variants in transfected cells by assessing their secretion, intracellular distribution, and markers of endoplasmic reticulum (ER) stress.
RESULTS: All three variants had secretion defects. Notably, the p.R188C and p.W419∗ variants induced misfolding of PNLIP and accumulated as detergent-insoluble aggregates resulting in elevated BiP at both protein and mRNA levels indicating increased ER stress.
CONCLUSIONS: All three novel PNLIP variants cause a loss-of-function through impaired secretion. Additionally, the p.R188C and p.W419∗ variants may induce proteotoxicity through misfolding and potentially increase the risk for pancreatic acinar cell injury.

BACKGROUND: Improvement in exocrine pancreatic function in persons with CF (pwCF) on cystic fibrosis transmembrane conductance regulator (CFTR) modulators has been documented in clinical trials using fecal pancreatic elastase-1 (FE-1). Our group endeavored to evaluate real-world data on FE-1 in children on CFTR modulator therapy at three pediatric cystic fibrosis (CF) centers.
METHODS: Pediatric pwCF were offered FE-1 testing if they were on pancreatic enzyme replacement therapy (PERT) and on CFTR modulator therapy according to their center\'s guideline. FE-1 data were collected retrospectively. The primary outcome was absolute change in FE-1.
RESULTS: 70 pwCF were included for analysis. 53 had baseline and post-modulator FE-1 values. There was a significant increase in FE-1 from median 25 mcg/g (IQR 25-60) at baseline to 57 mcg/g (IQR 20-228) post-modulator (p<0.001 by Wilcoxon matched pairs), with an absolute change in FE-1 of median 28 mcg/g (IQR -5-161) and mean 93.5 ± 146.8 mcg/g. Age was negatively correlated with change in FE-1 (Spearman r=-0.48, p<0.001). 15 pwCF (21%) had post-modulator FE-1 values ≥200 mcg/g, consistent with pancreatic sufficiency (PS). The PS group was significant for younger age at initiation of first CFTR modulator and a higher baseline FE-1.
CONCLUSIONS: Most pwCF experienced an increase in FE-1 while receiving CFTR modulator treatment and a small percentage demonstrated values reflective of PS. These data suggest that PS may be attained in those that initiated modulator therapy at a younger age or had a higher baseline FE-1. FE-1 testing is suggested for children on any CFTR modulator therapy.

The prevalence of celiac disease (CD) is approximately 1% in the US. Studies have shown possible association between exocrine pancreatic insufficiency (EPI) and CD, with numerous hypothesized biological mechanisms including small bowel mucosal damage causing disruption of enteric-mediated hormonal secretion such as cholecystokinin and loss of enterokinase. The overall prevalence of EPI in CD remains unknown. We performed systematic review and metanalysis and examined the prevalence of EPI in patients who were first diagnosed with CD versus those who had been on treatment with gluten-free diet (GFD). Results  Six studies were included in the analysis totaling 446 CD patients (Avg age 44.1 years; 34% Males). One hundred and forty-four patients had newly diagnosed CD, and 302 patients had known CD with at least 9 months treatment with GFD. Four studies examined newly diagnosed CD patients. The individual rates of EPI in new CD patients ranged from 10.5 to 46.5%. The pooled prevalence of EPI in newly diagnosed CD patients was 26.2% (95% CI 8.43-43.92%, Q = 2.24, I2 = 0%). Five studies examined CD patients on GFD. The rate of EPI ranged from 1.9% to 18.2%. The prevalence of EPI in patients treated with GFD is 8% (95% CI 1.52-14.8%, Q = 4.42, I2 = 9.59%). Patients with newly diagnosed CD are significantly more likely to have EPI compared to those patients treated with GFD (p = 0.031). CD patients on GFD with persistent symptoms have a significantly higher rate of EPI (28.4%) compared to CD patients on GFD who are asymptomatic (3%) (p < 0.001).

BACKGROUND: Quantitative fecal fat estimation is the gold standard test to diagnose steatorrhea (fecal fat >7 g/day) in chronic pancreatitis (CP), but cumbersome and inconvenient. So, fecal elastase-1 (FE) is proposed as a good alternative but the data on the diagnostic utility of FE to diagnose steatorrhea is variable.
METHODS: This retrospective study included adult CP patients evaluated with both 24-h fecal-fat and FE tests within a 3-month period. The objective was to evaluate the diagnostic performance of FE to diagnose steatorrhea and to evaluate the FE progression over 9-month period.
RESULTS: Among the 147 included patients, the frequency of steatorrhea (fecal fat >7 g/day) was 34%. The sensitivity, specificity, and negative likelihood ratio (LR) of FE was 90%, 28.9% and 0.35 at cut-off of <100 μg/g stool to diagnose steatorrhea; and 96%, 11.3% and 0.35 at cut-off of <200 μg/g stool, respectively. The optimal cut-off of FE was <20 on receiver operating characteristic curve (sensitivity 66%; specificity 69%; positive LR 2.14). There was no statistically significant variation in FE levels over 9 months interval among a hundred patients.
CONCLUSIONS: Compared to FE ≥ 200 μg/g stool, FE ≥ 100 can used to exclude steatorrhea (better specificity and negative LR). FE < 20 alone cannot replace fecal fat estimation to confirm steatorrhea but to be interpreted with clinical features. Repeat FE testing for exocrine insufficiency progression can be done at least a year later.

Cystic fibrosis transmembrane conductance regulator (CFTR) modulators improve pulmonary outcomes in subjects with cystic fibrosis (CF); however, the effects on pancreatic manifestations are not well characterized. We hypothesized that CFTR modulators would improve measures of exocrine pancreatic function and outcomes.
We performed a systematic search to identify studies reporting measures of the exocrine pancreas in humans treated with CFTR modulators. Only studies reporting baseline and on-treatment assessments were included.
Of 630 identified studies, 41 met inclusion criteria. CFTR modulators reduced acute pancreatitis events by 85% overall (rate ratio 0.15, 95% confidence interval (CI) 0.04, 0.52), with a greater effect seen in the subgroup with pancreas sufficient CF (PS-CF) (rate ratio 0.13 (95% CI 0.03, 0.53). Among 293 subjects with baseline and on-treatment evaluation of pancreas sufficiency, 253 were pancreas insufficient at baseline and 54 (21.3%) converted to pancreas sufficiency. Of 32 subjects with baseline FE-1 values <200 mcg/g, 16 (50%) increased to ≥200 mcg/g. Serum trypsin decreased by a mean of 565.9 ng/mL (standard deviation (SD) 311.8), amylase decreased by 38.2 U/L (SD 57.6), and lipase decreased by 232.3 U/L (SD 247.7).
CFTR modulator use reduces acute pancreatitis frequency and improves indirect measures of exocrine pancreas function. Future interventional studies that evaluate the mechanism and impact of CFTR modulators on acute pancreatitis and pancreas sufficiency in patients with CFTR dysfunction are warranted.

BACKGROUND: The functional and morphological recovery following an episode of acute pancreatitis (AP) in children still remains ill understood as research exploring this is limited. We aimed to characterize the morphological and functional changes in pancreas following AP and ARP (acute recurrent pancreatitis) in children.
METHODS: Children with AP were followed prospectively and assessed at two time points at least 3 months apart, with the first assessment at least 3 months after the AP episode. Exocrine and endocrine functions were measured using fecal elastase and fasting blood sugar/HbA1c levels respectively. Morphological assessment was done using endoscopic ultrasound (EUS) and magnetic resonance imaging and cholangiopancreatography (MRI/MRCP).
RESULTS: Seventy-three children (boys:59%; mean age:8.4 ± 3.2years) were studied and 21 of them (29%) progressed to ARP. Altered glucose homeostasis was seen in 19 (26%) at first and 16 (22%) at second assessment and it was significantly more in ARP group than the AP group at first (42.8%vs19.2%; p = 0.03) as well as second assessment (38.1%vs15.3%; p = 0.03). Twenty-one children (28.7%) at first and 24 (32.8%) at second assessment developed biochemical exocrine pancreatic insufficiency. EUS detected indeterminate and suggestive changes of chronic pancreatitis in 21% at first (n = 38) and 27.6% at second assessment (n = 58). On MRCP, main pancreatic duct and side branch dilatation were seen in 15 (20.5%) and 2 (2.7%) children respectively.
CONCLUSIONS: More than one-quarter of children have evidence of altered glucose homeostasis and biochemical exocrine pancreatic insufficiency following an episode of AP. Similarly, morphological features of chronicity seen in some of the children suggest that a fraction of subjects may develop chronic pancreatitis on longer follow-up.

OBJECTIVE: We evaluated exocrine pancreas functions using a noninvasive indicator in a case-control study conducted on children and adolescents diagnosed with type 1 diabetes mellitus.
METHODS: Sixty-seven patients who participated in a summer camp were enrolled in this study. Nineteen healthy children in the same age group were assigned to the control group. Fecal pancreatic elastase was assayed using the enzyme-linked immunosorbent assay technique. Values higher than 200 µg/g were considered an indication of sufficient exocrine pancreatic functioning, values between 100 µg/g and 200 µg/g were considered mild exocrine pancreatic insufficiency, and values below 100 µg/g were considered severe exocrine pancreatic insufficiency.
RESULTS: The mean concentration of fecal elastase was 158.38 ± 59.67 µg/g. The patients were assigned to three groups according to these values. Thirteen patients (22%) had sufficient fecal elastase levels, whereas 36 patients (62%) had mildly insufficient levels, and nine patients (16%) had severely insufficient fecal elastase concentrations. The levels of fecal elastase, amylase, lipase, and zinc were significantly different between the patients and controls (p < 0.001). Only the duration of diabetes was significantly different between patients with different severities of exocrine pancreatic insufficiency (p = 0.037). Additionally, the group with severe pancreatic insufficiency had more frequent hypoglycemic attacks.
CONCLUSIONS: Exocrine pancreatic insufficiency may develop in children with diabetes, and hypoglycemia attacks are observed more frequently depending on the severity of pancreatic insufficiency.

The data on exocrine pancreatic insufficiency (EPI) following gastric resectional surgery is variable, ranging from 26% to as high as 100%. This study aimed to document symptomatic EPI following gastric resectional surgery and to objectively document EPI, by fecal elastase (FE) testing. This was a cross-sectional study among patients undergoing gastric resection for adenocarcinoma of the stomach, at the Upper Gastrointestinal Surgical Unit at the Christian Medical College Hospital, Vellore, India. A detailed questionnaire was administered to the patients in the postoperative period, to evaluate clinical symptoms of EPI. Further, study participants were tested for FE pre- and postoperatively. Of the 60 patients in this study, the postoperative questionnaire administered to all patients during follow up. None showed symptoms suggestive of EPI. Pre- and post-operative FE testing were feasible in 27 of the 60 patients, which showed a 33% incidence of EPI. None of the patients had clinical symptoms of EPI, following gastric resectional surgery, on short-term follow-up. However, more than a third of the patients tested developed asymptomatic EPI after gastric resectional surgery, based on FE testing. This may be explained by the fact that in the early postoperative period, EPI following gastric resectional surgery perhaps has a mild, subclinical presentation. Therefore routine pancreatic supplementation after gastric resectional surgery may not be necessary. However, one needs to carefully look for worsening of symptoms of EPI on long-term follow-up, which may necessitate appropriate investigations followed by pancreatic enzyme replacement therapy.