Type of CFTR mutation determines risk of pancreatitis in patients with cystic fibrosis

Pancreatitis in cystic fibrosis: Presentation, medical and surgical management, and the impact of modulator therapies

Patients with Cystic Fibrosis (CF) are at increased risk of acute (AP) and chronic (CP) pancreatitis, and their complications. The extent of remaining healthy pancreatic parenchyma determines the risk of developing future episodes of pancreatitis, as well as pancreatic exocrine or endocrine insufficiency. Pancreatitis may be the presenting symptom of CF, and genetic testing is especially important in pediatrics. AP and recurrent AP are managed with intravenous fluid hydration and pain control, in addition to early refeeding and treatment of complications. With the use of modulator therapy in CF, pancreatic function may be restored to some extent. CP related pain is managed with analgesics and neuromodulators, with surgery if indicated in specific situations including TPIAT as a possible type of surgical intervention. Long-term sequelae of CP in patients with CF include exocrine pancreatic insufficiency treated with pancreatic enzyme replacement therapy, fat-soluble vitamin deficiencies and associated metabolic complications such as bone disease/osteoporosis, pancreatogenic diabetes, and less commonly, pancreatic cancer. We review the presentation and etiologies of pancreatitis in CF patients as well as the management of AP and CP primarily in children.

Pancreas and pancreatitis: Exocrine pancreatic insufficiency

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.

Exploring the enigmatic association between PNLIP variants and risk of chronic pancreatitis in a large Chinese cohort

BACKGROUND & AIMS

Protease-sensitive PNLIP variants were recently associated with chronic pancreatitis (CP) in European populations. The pathological mechanism yet remains elusive. Herein, we performed a comprehensive genetic and functional analysis of PNLIP variants found in a large Chinese cohort, aiming to further unravel the enigmatic association of PNLIP variants with CP.

METHODS

All coding and flanking intronic regions of the PNLIP gene were analyzed for rare variants by targeted next-generation sequencing in 1082 Chinese CP patients and 1196 controls. All novel missense variants were subject to analysis of secretion, lipase activity, and proteolytic degradation. One variant was further analyzed for its potential to misfold and induce endoplasmic reticulum (ER) stress. p.F300L, the most common PNLIP variant associated with CP, was used as a control.

RESULTS

We identified 12 rare heterozygous PNLIP variants, with 10 being novel. The variant carrier frequency did not differ between the groups. Of them, only the variant p.A433T found in a single patient was considered pathologically relevant. p.A433T exhibited increased susceptibility to proteolytic degradation, which was much milder than p.F300L. Interestingly, both variants exhibited an increased tendency to misfold, leading to intracellular retention as insoluble aggregates, reduced secretion, and elevated ER stress.

CONCLUSIONS

Our genetic and functional analysis of PNLIP variants identified in a Chinese CP cohort suggests that the p.A433T variant and the previously identified p.F300L variant are not only protease-sensitive but also may be potentially proteotoxic. Mouse studies of the PNLIP p.F300L and p.A433T variants are needed to clarify their role in CP.

Elevated Prostaglandin E2 Synthesis Is Associated with Clinical and Radiological Disease Severity in Cystic Fibrosis

Background: Previous studies found high but very variable levels of tetranor-PGEM and PGDM (urine metabolites of prostaglandin (PG) E2 and PGD2, respectively) in persons with cystic fibrosis (pwCF). This study aims to assess the role of cyclooxygenase COX-1 and COX-2 genetic polymorphisms in PG production and of PG metabolites as potential markers of symptoms' severity and imaging findings. Methods: A total of 30 healthy subjects and 103 pwCF were included in this study. Clinical and radiological CF severity was evaluated using clinical scoring methods and chest computed tomography (CT), respectively. Urine metabolites were measured using liquid chromatography/tandem mass spectrometry. Variants in the COX-1 gene (PTGS1 639 C>A, PTGS1 762+14delA and COX-2 gene: PTGS2-899G>C (-765G>C) and PTGS2 (8473T>C) were also analyzed. Results: PGE-M and PGD-M urine concentrations were significantly higher in pwCF than in controls. There were also statistically significant differences between clinically mild and moderate disease and severe disease. Patients with bronchiectasis and/or air trapping had higher PGE-M levels than patients without these complications. The four polymorphisms did not associate with clinical severity, air trapping, bronchiectasis, or urinary PG levels. Conclusions: These results suggest that urinary PG level testing can be used as a biomarker of CF severity. COX genetic polymorphisms are not involved in the variability of PG production.

Evaluation of Genetic Variants Associated with the Risk of Thiopurine-Related Pancreatitis: A Case Control Study from ENEIDA Registry

INTRODUCTION

Risk factors for developing pancreatitis due to thiopurines in patients with inflammatory bowel disease (IBD) are not clearly identified. Our aim was to evaluate the predictive pharmacogenetic risk of pancreatitis in IBD patients treated with thiopurines.

METHODS

We conducted an observational pharmacogenetic study of acute pancreatitis events in a cohort study of IBD patients treated with thiopurines from the prospectively maintained ENEIDA registry biobank of GETECCU. Samples were obtained and the CASR, CEL, CFTR, CDLN2, CTRC, SPINK1, CPA1, and PRSS1 genes, selected based on their known association with pancreatitis, were fully sequenced.

RESULTS

Ninety-five cases and 105 controls were enrolled; a total of 57% were women. Median age at pancreatitis diagnosis was 39 years. We identified 81 benign variants (50 in cases and 67 in controls) and a total of 35 distinct rare pathogenic and unknown significance variants (10 in CEL, 21 in CFTR, 1 in CDLN2, and 3 in CPA1). None of the cases or controls carried pancreatitis-predisposing variants within the CASR, CPA1, PRSS1, and SPINK1 genes, nor a pathogenic CFTR mutation. Four different variants of unknown significance were detected in the CDLN and CPA1 genes; one of them was in the CDLN gene in a single patient with pancreatitis and 3 in the CPA1 gene in 5 controls. After the analysis of the variants detected, no significant differences were observed between cases and controls.

CONCLUSION

In patients with IBD, genes known to cause pancreatitis seem not to be involved in thiopurine-related pancreatitis onset.

Standards for the care of people with cystic fibrosis (CF); recognising and addressing CF health issues

This is the third in a series of four papers updating the European Cystic Fibrosis Society (ECFS) standards for the care of people with CF. This paper focuses on recognising and addressing CF health issues. The guidance was produced with wide stakeholder engagement, including people from the CF community, using an evidence-based framework. Authors contributed sections, and summary statements which were reviewed by a Delphi consultation. Monitoring and treating airway infection, inflammation and pulmonary exacerbations remains important, despite the widespread availability of CFTR modulators and their accompanying health improvements. Extrapulmonary CF-specific health issues persist, such as diabetes, liver disease, bone disease, stones and other renal issues, and intestinal obstruction. These health issues require multidisciplinary care with input from the relevant specialists. Cancer is more common in people with CF compared to the general population, and requires regular screening. The CF life journey requires mental and emotional adaptation to psychosocial and physical challenges, with support from the CF team and the CF psychologist. This is particularly important when life gets challenging, with disease progression requiring increased treatments, breathing support and potentially transplantation. Planning for end of life remains a necessary aspect of care and should be discussed openly, honestly, with sensitivity and compassion for the person with CF and their family. CF teams should proactively recognise and address CF-specific health issues, and support mental and emotional wellbeing while accompanying people with CF and their families on their life journey.

ESPEN-ESPGHAN-ECFS guideline on nutrition care for cystic fibrosis

BACKGROUND

Nutritional status is paramount in Cystic Fibrosis (CF) and is directly correlated with morbidity and mortality. The first ESPEN-ESPGHAN-ECFS guidelines on nutrition care for infants, children, and adults with CF were published in 2016. An update to these guidelines is presented.

METHODS

The study was developed by an international multidisciplinary working group in accordance with officially accepted standards. Literature since 2016 was reviewed, PICO questions were discussed and the GRADE system was utilized. Statements were discussed and submitted for on-line voting by the Working Group and by all ESPEN members.

RESULTS

The Working Group updated the nutritional guidelines including assessment and management at all ages. Supplementation of vitamins and pancreatic enzymes remains largely the same. There are expanded chapters on pregnancy, CF-related liver disease, and CF-related diabetes, bone disease, nutritional and mineral supplements, and probiotics. There are new chapters on nutrition with highly effective modulator therapies and nutrition after organ transplantation.

A narrative review on the role of genetics in children with acute recurrent pancreatitis and chronic pancreatitis

The incidence of pancreatitis in children has increased over the past two decades. With advances in molecular biological techniques and clinical research, genetic variations have emerged as a pivotal etiological factor in pediatric pancreatitis. This review aims to summarize recent clinical research advancements in understanding pediatric pancreatitis caused by various gene mutations. As of the year 2020, researchers had identified 12 genes implicated in the pathogenesis of pancreatitis. These genes primarily contributed to the development of pancreatitis through three mechanisms. Pancreatitis resulting from these gene mutations exhibits several distinct characteristics, including early onset, a heightened risk of developing pancreatic duct stones, rapid disease progression, and a significantly increased risk of pancreatic endocrine and exocrine dysfunction, as well as pancreatic cancer in the future. Genetic sequencing is recommended for children with pancreatitis based on six indications. The sequencing not only assists in the clinical diagnosis but also enhances our understanding of the pathophysiology of pancreatitis.

Pathogenicity and virulence of Aspergillus fumigatus

Pulmonary infections caused by the mould pathogen Aspergillus fumigatus are a major cause of morbidity and mortality globally. Compromised lung defences arising from immunosuppression, chronic respiratory conditions or more recently, concomitant viral or bacterial pulmonary infections are recognised risks factors for the development of pulmonary aspergillosis. In this review, we will summarise our current knowledge of the mechanistic basis of pulmonary aspergillosis with a focus on emerging at-risk populations.

Delayed identification of compound heterozygous (Phe508del/Arg117His) cystic fibrosis variants in a patient awaiting liver transplantation

A man in his 60s undergoing liver transplant assessment was referred to the respiratory team after a thoracic CT scan revealed diffuse tree-in-bud changes. He had a history of infertility, chronic pancreatitis and liver cirrhosis with portal hypertension. Broncho-alveolar lavage was positive for Pseudomonas aeruginosa Genetic screening found two cystic fibrosis transmembrane conductance regulator variants: Phe508del and Arg117His-7T. The patient was referred to the regional cystic fibrosis (CF) centre for follow-up but died from hepatobiliary complications. The atypical presentation with relatively late onset of pulmonary disease and hepatobiliary disease predominance created a diagnostic challenge. This case is a reminder that while CF is a monogenic disorder, its manifestation, natural history and extent can be highly variable. Taking a thorough medical history of any chronic illness is essential, and patients with the appropriate clinical presentation, regardless of age, should be investigated for CF.

A Gastroenterologist's Guide to Care Transitions in Cystic Fibrosis from Pediatrics to Adult Care

Cystic Fibrosis is a chronic disease affecting multiple systems, including the GI tract. Clinical manifestation in patients can start as early as infancy and vary across different age groups. With the advent of new, highly effective modulators, the life expectancy of PwCF has improved significantly. Various GI aspects of CF care, such as nutrition, are linked to an overall improvement in morbidity, lung function and the quality of life of PwCF. The variable clinical presentations and management of GI diseases in pediatrics and adults with CF should be recognized. Therefore, it is necessary to ensure efficient transfer of information between pediatric and adult providers for proper continuity of management and coordination of care at the time of transition. The transition of care is a challenging process for both patients and providers and currently there are no specific tools for GI providers to help ensure a smooth transition. In this review, we aim to highlight the crucial features of GI care at the time of transition and provide a checklist that can assist in ensuring an effective transition and ease the challenges associated with it.

Nutritional management of people living with cystic fibrosis throughout life and disease continuum: Changing times, new challenges

Cystic fibrosis (CF) is a genetic disease caused by mutations in the gene encoding for the ion channel cystic fibrosis transmembrane conductance regulator (CFTR). The management of CF disease has evolved in recent decades from treating downstream disease manifestations affecting the airways, the lungs and the gastrointestinal system to addressing the CFTR gene defect. The advent of CFTR modulators, which correct the functionality of the defective CFTR, contributes to reshaping the landscape of CF demographics, prognosis and therapies, including nutritional management. A spectrum of clinical manifestations is emerging within the same patient population where undernutrition and nutritional deficiencies coexist with excessive weight gain and metabolic derangements. Such contrasting presentations challenge current practices, require adjustments to traditional approaches, and involve more individualised interventions. This narrative review examines the current state of knowledge on the nutritional management of people living with cystic fibrosis from early life to adulthood in the era of CFTR modulation.

Inherited causes of exocrine pancreatic insufficiency in pediatric patients: clinical presentation and laboratory testing

Pediatric patients with exocrine pancreatic insufficiency (EPI) have symptoms that include abdominal pain, weight loss or poor weight gain, malnutrition, and steatorrhea. This condition can be present at birth or develop during childhood for certain genetic disorders. Cystic fibrosis (CF) is the most prevalent disorder in which patients are screened for EPI; other disorders also are associated with pancreatic dysfunction, such as hereditary pancreatitis, Pearson syndrome, and Shwachman-Diamond syndrome. Understanding the clinical presentation and proposed pathophysiology of the pancreatic dysfunction of these disorders aids in diagnosis and treatment. Testing pancreatic function is challenging. Directly testing aspirates produced from the pancreas after stimulation is considered the gold standard, but the procedures are not standardized or widely available. Instead, indirect tests are often used in diagnosis and monitoring. Although indirect tests are more widely available and easier to perform, they have inherent limitations due to a lack of sensitivity and/or specificity for EPI.

CFTR-beyond the airways: Recent findings on the role of the CFTR channel in the pancreas, the intestine and the kidneys

With increased longevity of patients suffering from cystic fibrosis, and widespread lung transplantation facilities, the sequelae of defective CFTR in other organs than the airways come to the fore. This minireview highlights recent scientific progress in the understanding of CFTR function in the pancreas, the intestine and the kidney, and explores potential therapeutic strategies to combat defective CFTR function in these organs.

Mesenchymal stem cells in fibrotic diseases-the two sides of the same coin

Fibrosis is caused by extensive deposition of extracellular matrix (ECM) components, which play a crucial role in injury repair. Fibrosis attributes to ~45% of all deaths worldwide. The molecular pathology of different fibrotic diseases varies, and a number of bioactive factors are involved in the pathogenic process. Mesenchymal stem cells (MSCs) are a type of multipotent stem cells that have promising therapeutic effects in the treatment of different diseases. Current updates of fibrotic pathogenesis reveal that residential MSCs may differentiate into myofibroblasts which lead to the fibrosis development. However, preclinical and clinical trials with autologous or allogeneic MSCs infusion demonstrate that MSCs can relieve the fibrotic diseases by modulating inflammation, regenerating damaged tissues, remodeling the ECMs, and modulating the death of stressed cells after implantation. A variety of animal models were developed to study the mechanisms behind different fibrotic tissues and test the preclinical efficacy of MSC therapy in these diseases. Furthermore, MSCs have been used for treating liver cirrhosis and pulmonary fibrosis patients in several clinical trials, leading to satisfactory clinical efficacy without severe adverse events. This review discusses the two opposite roles of residential MSCs and external MSCs in fibrotic diseases, and summarizes the current perspective of therapeutic mechanism of MSCs in fibrosis, through both laboratory study and clinical trials.

CFTR-Related Metabolic Syndrome: Genetic Variants Increasing Pancreatitis Risk in the Pediatric Puerto Rican Population

CFTR-related metabolic syndrome (CRMS) is a novel diagnosis due to widespread use of and advances in the newborn screening (NBS) process for cystic fibrosis (CF) in the United States of America, allowing for the diagnosis of asymptomatic children with CF. Before 2015, a large Puerto Rican pediatric population was not screened for CF in the NBS test. Studies have shown that patients presenting with idiopathic recurrent or chronic pancreatitis have an increased frequency of cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations. We present a retrospective chart review of 12 pediatric cases (n = 12) that were presented to an outpatient community clinic with clinical manifestations associated with CF. The pancreatic insufficiency prevalence (PIP) score was calculated on CFTR mutations. The mutations considered for the calculation of the PIP score were: F508del (c.1521_1523del), V201M (c.601G > A), I507del (c.1519_1521del), and L1335P (c.4004T > C). V201M mutation was classified as mild in both PIP scores, and a correlation with pancreatitis was noted. Clinical manifestations vary in cases with the V201M variant (c.601G > A). One case was diagnosed with CFTR-related disorder (CRD) and recurrent pancreatitis. It is important to consider CRMS or CRD as a differential diagnosis in the pediatric population of Puerto Rico due to the implications and increased risk of pancreatitis and other CF-related complications.

Analysis of INSPPIRE-2 Cohort: Risk Factors and Disease Burden in Children With Acute Recurrent or Chronic Pancreatitis

OBJECTIVES

The objective of this study is to investigate risk factors and disease burden in pediatric acute recurrent pancreatitis (ARP) and chronic pancreatitis (CP).

METHODS

Data were obtained from INternational Study group of Pediatric Pancreatitis: In search for a cuRE-2 (INSPPIRE-2), the largest multi-center prospective cohort study in pediatric patients with ARP or CP.

RESULTS

Of 689 children, 365 had ARP (53%), 324 had CP (47%). CP was more commonly associated with female sex, younger age at first acute pancreatitis (AP) attack, Asian race, family history of CP, lower BMI%, genetic and obstructive factors, PRSS1 mutations and pancreas divisum. CFTR mutations, toxic-metabolic factors, medication use, hypertriglyceridemia, Crohn disease were more common in children with ARP. Constant or frequent abdominal pain, emergency room (ER) visits, hospitalizations, medical, endoscopic or surgical therapies were significantly more common in CP, episodic pain in ARP. A total of 33.1% of children with CP had exocrine pancreatic insufficiency (EPI), 8.7% had diabetes mellitus. Compared to boys, girls were more likely to report pain impacting socialization and school, medical therapies, cholecystectomy, but no increased opioid use. There was no difference in race, ethnicity, age at first AP episode, age at CP diagnosis, duration of disease, risk factors, prevalence of EPI or diabetes between boys and girls. Multivariate analysis revealed that family history of CP, constant pain, obstructive risk factors were predictors of CP.

CONCLUSIONS

Children with family history of CP, constant pain, or obstructive risk factors should raise suspicion for CP.

Elevated Levels of Toxic Bile Acids in Serum of Cystic Fibrosis Patients with CFTR Mutations Causing Pancreatic Insufficiency

Hepatobiliary involvement is a hallmark in cystic fibrosis (CF), as the causative CF Transmembrane Conductance Regulator (CFTR) defect is expressed in the biliary tree. However, bile acid (BA) compositions in regard to pancreatic insufficiency, which is present at an early stage in about 85% of CF patients, have not been satisfactorily understood. We assess the pattern of serum BAs in people with CF (pwCF) without CFTR modulator therapy in regard to pancreatic insufficiency and the CFTR genotype. In 47 pwCF, 10 free and 12 taurine- and glycine-conjugated BAs in serum were prospectively assessed. Findings were related to genotype, pancreatic insufficiency prevalence (PIP)-score, and hepatic involvement indicated by serum liver enzymes, as well as clinical and ultrasound criteria for CF-related liver disease. Serum concentrations of total primary BAs and free cholic acid (CA) were significantly higher in pwCF with higher PIP-scores (p = 0.025, p = 0.009, respectively). Higher total BAs were seen in pwCF with PIP-scores ≥0.88 (p = 0.033) and with pancreatic insufficiency (p = 0.034). Free CA was higher in patients with CF-related liver involvement without cirrhosis, compared to pwCF without liver disease (2.3-fold, p = 0.036). pwCF with severe CFTR genotypes, as assessed by the PIP-score, reveals more toxic BA compositions in serum. Subsequent studies assessing changes in BA homeostasis during new highly effective CFTR-modulating therapies are of high interest.

Surgical considerations in cystic fibrosis: what every general surgeon needs to know

Cystic fibrosis (CF) is a complex multiorgan disease, which often affects the gastrointestinal tract. With improved CF specific therapies and multidisciplinary management, patients with CF are now living longer with a median life expectancy of around 50 years. This increased life expectancy has resulted in corresponding increase in presentations of the CF patient with comorbid surgical conditions that were never important considerations. Investigations and management of these conditions, such as distal intestinal obstruction syndrome and colorectal cancer warrant good clinical understanding of the unique challenges that CF patients present including chronic immunosuppression, impaired respiratory function and their multi-organ dysfunction. The purpose of this review is to provide general surgeons with a contemporary update on the CF related surgical issues as they are likely to become increasingly involved in the care of these complex patients and form an integral part of the multidisciplinary team.

Analysis of the genotypic profile and its relationship with the clinical manifestations in people with cystic fibrosis: study from a rare disease registry

Background

Cystic fibrosis (CF) has a vast and heterogeneous mutational spectrum in Europe. This variability has also been described in Spain, and there are numerous studies linking CFTR variants with the symptoms of the disease. Most of the studies analysed determinate clinical manifestations or specific sequence variants in patients from clinical units. Others used registry data without addressing the genotype–phenotype relationship. Therefore, the objective of this study is to describe the genetic and clinical characteristics of people with CF and to analyse the relationship between both using data from the rare disease registry of a region in southeastern Spain.

Methods

A cross-sectional study was carried out in people with a confirmed diagnosis of CF registered in the Rare Diseases Information System (SIER) of the Region of Murcia (Spain). The patients were classified into two genotypes according to the functional consequence that the genetic variants had on the CFTR protein.

Results

There were 192 people diagnosed with CF reported in the Region of Murcia as of 31 December 2018. Seventy-six genotypes and 49 different variants were described, with c.1521_1523delCTT (p. Phe508del) being the most common in 58.3% of the CF patients and 37.0% of the alleles. In addition, 67% of the patients were classified as a high-risk genotype, which was associated with a lower percentage of FEV₁ (OR: 5.3; 95% CI: 1.2, 24.4), an increased risk of colonization by Pseudomonas aeruginosa (OR: 7.5; 95% CI: 1.7, 33.0) and the presence of pancreatic insufficiency (OR: 28.1; 95% CI: 9.3, 84.4) compared to those with a low-risk genotype.

Conclusions

This is the first study in Spain that describes the mutational spectrum and its association with clinical manifestations in patients with CF using data from a rare disease registry. The results obtained allow planning for the health resources needed by people with this disease, thus contributing to the development of personalized medicine that helps to optimize health care in CF patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-022-02373-y.

Current clinical opinion on CFTR dysfunction and patient risk of pancreatitis: diagnostic and therapeutic considerations

INTRODUCTION

Cystic fibrosis transmembrane conductance regulator (CFTR)-mediated chloride and bicarbonate secretion is integral to the pancreas' ability to produce the alkaline pancreatic juice required for proper activation of enzymes for digestion. Disruption in this process increases the risk for pancreatitis.

AREAS COVERED

Using original basic and clinical research, as well as clinical case reports and recent reviews indexed in PubMed, we discuss why patients with CFTR dysfunction are at risk for pancreatitis. We also discuss diagnostic modalities for assessing CFTR function, as well as new therapeutic advancements and the impact these are having on pancreatic function, pancreatitis in particular.

EXPERT OPINION

CFTR-related pancreatitis occurs in the presence of monallelic or biallelic mutations and/or from toxin-mediated channel disruption. Research-based CFTR diagnostics have been expanded, yet all current methods rely on measuring CFTR chloride transport in non-pancreatic cells/tissue. Newer CFTR-directed therapies ('CFTR modulators') are both improving pancreatitis (pancreatic-sufficient CF patients) and increasing the risk for pancreatitis (previously pancreatic-insufficient CF patients). Our experiences with these drugs are enlightening us on how CFTR modulation can affect pancreatitis risk across a wide spectrum of pancreatic disease, and represents an opportunity for therapeutic relief from pancreatitis in those without CF, but who suffer from CFTR-related pancreatitis.

Gene Polymorphism of Biotransformation Enzymes and Ciprofloxacin Pharmacokinetics in Pediatric Patients with Cystic Fibrosis

(1) Background: Ciprofloxacin (CPF) is widely used for the treatment of cystic fibrosis, including pediatric patients, but its pharmacokinetics is poorly studied in this population. Optimal CPF dosing in pediatric patients may be affected by gene polymorphism of the enzymes involved in its biotransformation. (2) Materials and Methods: a two-center prospective non-randomized study of CPF pharmacokinetics with sequential enrollment of patients (n-33, mean age 9.03 years, male-33.36%), over a period from 2016 to 2021. All patients received tablets of the original CPF drug Cyprobay® at a dose of 16.5 mg/kg to 28.80 mg/kg. Blood sampling schedule: 0 (before taking the drug), 1.5 h; 3.0 h; 4.5 h; 6.0 h; 7.5 h after the first dosing. CPF serum concentrations were analyzed by high performance liquid chromatography mass spectrometry. The genotype of biotransformation enzymes was studied using total DNA isolated from whole blood leukocytes by the standard method. (4) Results: a possible relationship between the CA genotype of the CYP2C9 gene (c.1075A > C), the GG genotype of the CYP2D6*4 gene (1846G > A), the AG genotype of the GSTP1 gene (c.313A > G), the GCLC* genotype 7/7 and the CPF concentration in plasma (increased value of the area under the concentration−time curve) was established. Conclusions: Gene polymorphism of biotransformation enzymes may affect ciprofloxacin pharmacokinetics in children.

Pancreatic Insufficiency in a Child with p.Gly542* and c.2657+5G>A Heterozygote CFTR: A Case Report

Cystic fibrosis is a monogenic and autosomal recessive disease. It is caused by mutations in the Cystic Fibrosis Transmembrane Conductance Regulator gene responsible for encoding the CFTR protein. Involvement of the gastrointestinal and respiratory systems is the main clinical manifestation. In this case, we report a heterozygous CFTR patient harboring class I (p.Gly542*) and class V (c.2657+5G>A) mutations. The importance of this case report lies in the clinical features because the patient, aged 3 years, presented with early exocrine pancreatic insufficiency, which can be considered atypical, as most individuals with this genotype are pancreatic sufficient or develop pancreatic insufficiency later in life. This report aims at presenting the tests requested that contributed to the patient's diagnosis, as well as at understanding the association between these mutations and their phenotypic presentation. Interpretation of the genotype-phenotype relationship represents a challenge, as genetic analysis alone is not sufficient to clearly predict severity of the disease. This is because the significant phenotypic heterogeneity existing among patients with the same genotype may exert socioeconomic and sociocultural influences, or by the action of CFTR modifiers, such as environmental and modifying genes, which can alter the protein's function and exert an impact on the individual's phenotype.

Digestive outcomes in Cystic fibrosis

Cystic fibrosis (CF) is the most frequent life-limiting autosomal recessive disease in Caucasians, affecting the respiratory tract, but also the pancreas, gut, and hepatobiliary tract. CF is caused by variants in the Cystic Fibrosis Transmembrane conductance Regulator (CFTR) gene. Prognosis of CF has markedly improved over the last 20 years because of the management in CF centers and recent introduction of CFTR modulators, aimed at correcting the defective CFTR protein. There are nowadays more CF adults than children, with a predicted median survival age of around 50 years in high-income countries. Around 85% of CF patients have pancreatic insufficiency present at birth. Gastroesophageal reflux disease (GERD) is more frequent in CF patients, but its role on decline in lung health is controversial. Distal small bowel obstruction syndrome (DIOS) caused by meconium-like stool plugs occurs at any age after the neonatal period, affecting up to 15-20% of CF patients. Because of increased life expectancy, most CF patients are expected to live to their fifties or beyond, when cancer is more frequent. In addition, CF is associated with a higher risk for GI malignancy as compared with the general population. Colorectal cancer represents the most significant risk, and colonoscopy-based screening is recommended from 40 years of age onwards. Other digestive outcomes in CF reviewed in this paper include meconium ileus, Clostridium difficile infection, intussusception, acute appendicitis, small intestinal bacterial overgrowth, appendiceal mucocele and rectal prolapse. Every CF Center should comprise a gastroenterologist with expertise in the care of CF patients.

CFTR:F508d/A613T Mutation Is Associated With Recurrent Episodes of Pancreatitis

Pancreatic insufficiency (PI) is found in 85% of individuals with cystic fibrosis (CF). Of the remaining who are pancreatic sufficient (PS), there is potential for developing pancreatitis, and is described in ~20% of PS individuals. We report a case of a 17.5-year-old female presenting with acute recurrent pancreatitis (ARP) and PS, later diagnosed with CF. This is the first reported case of ARP in an individual with a F508d/A613T genotype. To date, there are only 6 other individuals with this genotype, and the mechanisms of it causing ARP and no overt respiratory symptoms of CF are unclear. Her diagnosis occurred 10 years after her initial presentation of pancreatitis, highlighting the importance of screening for CFTR mutations in the workup for ARP with no clear etiology.

Intestinal Inflammation and Alterations in the Gut Microbiota in Cystic Fibrosis: A Review of the Current Evidence, Pathophysiology and Future Directions

Cystic fibrosis (CF) is a life-limiting autosomal recessive multisystem disease. While its burden of morbidity and mortality is classically associated with pulmonary disease, CF also profoundly affects the gastrointestinal (GI) tract. Chronic low-grade inflammation and alterations to the gut microbiota are hallmarks of the CF intestine. The etiology of these manifestations is likely multifactorial, resulting from cystic fibrosis transmembrane conductance regulator (CFTR) dysfunction, a high-fat CF diet, and the use of antibiotics. There may also be a bidirectional pathophysiological link between intestinal inflammation and changes to the gut microbiome. Additionally, a growing body of evidence suggests that these GI manifestations may have significant clinical associations with growth and nutrition, quality of life, and respiratory function in CF. As such, the potential utility of GI therapies and long-term GI outcomes are areas of interest in CF. Further research involving microbial modulation and multi-omics techniques may reveal novel insights. This article provides an overview of the current evidence, pathophysiology, and future research and therapeutic considerations pertaining to intestinal inflammation and alterations in the gut microbiota in CF.

What Do We Know about the Microbiome in Cystic Fibrosis? Is There a Role for Probiotics and Prebiotics?

Cystic fibrosis (CF) is a life-shortening genetic disorder that affects the cystic fibrosis transmembrane conductance regulator (CFTR) protein. In the gastrointestinal (GI) tract, CFTR dysfunction results in low intestinal pH, thick and inspissated mucus, a lack of endogenous pancreatic enzymes, and reduced motility. These mechanisms, combined with antibiotic therapies, drive GI inflammation and significant alteration of the GI microbiota (dysbiosis). Dysbiosis and inflammation are key factors in systemic inflammation and GI complications including malignancy. The following review examines the potential for probiotic and prebiotic therapies to provide clinical benefits through modulation of the microbiome. Evidence from randomised control trials suggest probiotics are likely to improve GI inflammation and reduce the incidence of CF pulmonary exacerbations. However, the highly variable, low-quality data is a barrier to the implementation of probiotics into routine CF care. Epidemiological studies and clinical trials support the potential of dietary fibre and prebiotic supplements to beneficially modulate the microbiome in gastrointestinal conditions. To date, limited evidence is available on their safety and efficacy in CF. Variable responses to probiotics and prebiotics highlight the need for personalised approaches that consider an individual’s underlying microbiota, diet, and existing medications against the backdrop of the complex nutritional needs in CF.

Geographic distribution and phenotype of European people with cystic fibrosis carrying A1006E mutation

BACKGROUND

A1006E is a Cystic Fibrosis (CF) mutation that is still not widely known. We report phenotypic features and geographic distribution of the largest cohort of people with CF (pwCF) carrying A1006E to date.

METHODS

Study of European pwCF carrying A1006E mutation, included in the European CF Society Patient Registry (ECFSPR). Genotype, ancestries and all variables recorded were compared to a cohort of F508del/F508del patients. Rate of decline in percentage-of-predicted FEV₁ (ppFEV₁) was also analyzed using the 2010-2017 ECFSPR.

RESULTS

44 pwCF carrying A1006E were reported (59% males), median age 33 years old (3-58), 54.5% Spanish and 40.9% Italian, most with ancestry in Murcia (Spain) and Lazio (Italy) regions. Compared to F508del homozygous, A1006E-pwCF were significantly older (75% vs. 52.5% ≥ 18 years old) and diagnosed at later median age (6.98 vs. 0.29 years); showed lower rates of meconium ileus (2.33% vs. 17.7%), pancreatic insufficiency (27.91% vs. 99.26%), diabetes (2.33% vs. 21.98%), liver disease (6.98% vs. 36.72%) and Pseudomonas aeruginosa chronic colonization (30.95% vs. 42.51%); and presented better nutrition (BMI z-score 0.44 vs. -0.43) and ppFEV₁ (90.8% vs. 78.6%), with 18.9% (most >40 years old) having a ppFEV₁<70%. Additional ppFEV₁ decline (0.96% per year) was attributed to F508del/F508del genotype (p = 0.0007). None died or needed organ transplantation during the study period.

CONCLUSIONS

A1006E-pwCF are mainly of Western Mediterranean Spanish and Italian descent. When compared with F508del/F508del-pwCF, they usually have a milder form of the disease, associated with pancreatic sufficiency and slower FEV₁ decline. However, some will develop progressive respiratory impairment during adulthood.

The Exocrine Pancreas in Cystic Fibrosis in the Era of CFTR Modulation: A Mini Review

Cystic fibrosis (CF) is a common disorder of autosomal recessive inheritance, that once conferred a life expectancy of only a few months. Over recent years, significant advances have been made to CF therapeutic approaches, changing the face of the disease, and facilitating the partial restoration of pancreatic function. This mini review summarizes the current landscape of exocrine pancreatic management in CF and explores areas for future direction and development.

Receptor Guanylyl Cyclase C and Cyclic GMP in Health and Disease: Perspectives and Therapeutic Opportunities

Receptor Guanylyl Cyclase C (GC-C) was initially characterized as an important regulator of intestinal fluid and ion homeostasis. Recent findings demonstrate that GC-C is also causally linked to intestinal inflammation, dysbiosis, and tumorigenesis. These advances have been fueled in part by identifying mutations or changes in gene expression in GC-C or its ligands, that disrupt the delicate balance of intracellular cGMP levels and are associated with a wide range of clinical phenotypes. In this review, we highlight aspects of the current knowledge of the GC-C signaling pathway in homeostasis and disease, emphasizing recent advances in the field. The review summarizes extra gastrointestinal functions for GC-C signaling, such as appetite control, energy expenditure, visceral nociception, and behavioral processes. Recent research has expanded the homeostatic role of GC-C and implicated it in regulating the ion-microbiome-immune axis, which acts as a mechanistic driver in inflammatory bowel disease. The development of transgenic and knockout mouse models allowed for in-depth studies of GC-C and its relationship to whole-animal physiology. A deeper understanding of the various aspects of GC-C biology and their relationships with pathologies such as inflammatory bowel disease, colorectal cancer, and obesity can be leveraged to devise novel therapeutics.

Bicarbonate Transport in Cystic Fibrosis and Pancreatitis

CFTR, the cystic fibrosis (CF) gene-encoded epithelial anion channel, has a prominent role in driving chloride, bicarbonate and fluid secretion in the ductal cells of the exocrine pancreas. Whereas severe mutations in CFTR cause fibrosis of the pancreas in utero, CFTR mutants with residual function, or CFTR variants with a normal chloride but defective bicarbonate permeability (CFTR^BD), are associated with an enhanced risk of pancreatitis. Recent studies indicate that CFTR function is not only compromised in genetic but also in selected patients with an acquired form of pancreatitis induced by alcohol, bile salts or smoking. In this review, we summarize recent insights into the mechanism and regulation of CFTR-mediated and modulated bicarbonate secretion in the pancreatic duct, including the role of the osmotic stress/chloride sensor WNK1 and the scaffolding protein IRBIT, and current knowledge about the role of CFTR in genetic and acquired forms of pancreatitis. Furthermore, we discuss the perspectives for CFTR modulator therapy in the treatment of exocrine pancreatic insufficiency and pancreatitis and introduce pancreatic organoids as a promising model system to study CFTR function in the human pancreas, its role in the pathology of pancreatitis and its sensitivity to CFTR modulators on a personalized basis.

Inherited pancreatic exocrine insufficiency and pancreatitis: When children transition to adult care

Hereditary pancreatitis (HP) encompasses two distinct disease groups: the first manifests as congenital exocrine pancreatic insufficiency (EPI), and the second includes hereditary forms of pancreatitis. EPI represents the ultimate expression of gland function loss. Cystic fibrosis is by far the most frequent aetiology of early-onset EPI; genetics and a growing understanding of the disease mechanisms have paved the way for innovative and personalized treatment approaches. Efforts are ongoing to further decipher the pathophysiology and explore new therapies for other causes of EPI. HP occurs in patients carrying mutations in genes encoding digestive proteases or proteins playing an important role in proper pancreatic function and homeostasis. Improved sequencing techniques have led to the discovery of several causal and disease promoting genes. Most forms of HP have a paediatric onset but complications usually manifest during adulthood. Surveillance in experienced centres is mandatory to diagnose and address these complications in a timely manner.

CFTR modulators increase risk of acute pancreatitis in pancreatic insufficient patients with cystic fibrosis

Patients with pancreatic insufficient cystic fibrosis rarely develop acute pancreatitis due to insufficient acinar reserve. We describe a series of five patients under the age of 18 (range 8-16 years) with pancreatic insufficient cystic fibrosis who developed a phenotype in keeping with acute pancreatitis following initiation of CFTR modulator therapy. This occurred at a median of 30 months following CFTR modulator initiation. 3/5 of these patients also developed pancreatic sufficiency or at least an intermediary pancreas status, indicated by fecal elastases above 100 μg/g. This series highlights a mostly unrecognized potential side effect of this therapy as well as the potential of CFTR modulator therapies to improve exocrine pancreatic function, even in adolescent patients.

Mislocalization of CFTR expression in acute pancreatitis and the beneficial effect of VX-661 + VX-770 treatment on disease severity

Cystic fibrosis transmembrane conductance regulator (CFTR) has an essential role in maintaining pancreatic ductal function. Impaired CFTR function can trigger acute pancreatitis (AP) and exacerbate disease severity. We aimed to investigate the localization and expression of CFTR during AP, and determined the effects of a CFTR corrector (VX-661) and potentiator (VX-770) on disease severity. AP was induced in FVB/n mice by 6-10 hourly intraperitoneal injections of 50 μg/kg cerulein. Some mice were pre-treated with five to six daily injections of 2 mg/kg VX-661 + VX-770. Control animals were administered physiological saline instead of cerulein and dimethyl sulfoxide instead of VX compounds. AP severity was determined by measuring laboratory and histological parameters; CFTR and CK19 expression was measured. Activity of ion transporters was followed by intracellular pH or fluid secretion measurement of isolated pancreatic intra-/interlobular ducts. Cerulein-induced AP severity was greatest between 12 and 24 h. CFTR mRNA expression was significantly increased 24 h after AP induction. Immunohistochemistry demonstrated disturbed staining morphology of CFTR and CK19 proteins in AP. Mislocalization of CFTR protein was observed from 6 h, while expression increased at 24 h compared to control. Ductal HCO₃ ^- transport activity was significantly increased 6 h after AP induction. AP mice pre-treatment with VX-661 + VX-770 significantly reduced the extent of tissue damage by about 20-30%, but other parameters were unchanged. Interestingly, VX-661 + VX-770 in vitro administration significantly increased the fluid secretion of ducts derived from AP animals. This study described the course of the CFTR expression and mislocalization in cerulein-induced AP. Our results suggest that the beneficial effects of CFTR correctors and potentiators should be further investigated in AP. KEY POINTS: Cystic fibrosis transmembrane conductance regulator (CFTR) is an important ion channel in epithelial cells. Its malfunction has several serious consequences, like developing or aggravating acute pancreatitis (AP). Here, the localization and expression of CFTR during cerulein-induced AP in mice were investigated and the effects of CFTR corrector (VX-661) and a potentiator (VX-770) on disease severity were determined. CFTR mRNA expression was significantly increased and mislocalization of CFTR protein was observed in AP compared to the control group. Interestingly, pre-treatment of AP mice with VX-661 + VX-770 significantly reduced the extent of pancreatic tissue damage by 20-30%. In vitro administration of VX-661 + VX-770 significantly increased the fluid secretion of ducts derived from AP animals. Based on these results, the utilization of CFTR correctors and potentiators should be further investigated in AP.

Demographics and risk factors for pediatric recurrent acute pancreatitis

PURPOSE OF REVIEW

Approximately 20-30% of children who experience one episode of acute pancreatitis will have at least one additional episode. For some children, pancreatitis recurs multiple times and in a few years is followed by the diagnosis of chronic pancreatitis. Identifying risk factors for recurrent episodes and disease progression is critical to developing therapeutic interventions.

RECENT FINDINGS

Obesity is driving an increase in biliary stone disease and severe acute pancreatitis. Recurrent acute pancreatitis (RAP) may lead to the development of diabetes through autoimmune mechanisms. Cystic fibrosis or CFTR-related disorders may present as RAP and CFTR modulator therapy can increase or decrease the risk of acute pancreatitis in these populations. Children with Crohn disease have a three-fold risk of acute pancreatitis over the general population while children with ulcerative colitis are at increased risk for pediatric autoimmune pancreatitis, a disorder that may be distinct from autoimmune pancreatitis described in adults. Obstructive jaundice in the absence of identified mechanical factors may be a presenting sign of pediatric autoimmune pancreatitis.

SUMMARY

Pediatric RAP is a painful condition that leads to gland destruction and functional insufficiency. Risk factors are being clarified but preventive treatments remain elusive.

Timing of pancreatic enzyme replacement therapy (PERT) in cystic fibrosis

BACKGROUND

Cystic fibrosis (CF) is an autosomal recessive, life-limiting, multisystem disease affecting over 70,000 individuals worldwide. Between 80% and 90% of people with CF suffer with pancreatic exocrine insufficiency, which if left untreated, leads to a poor nutritional status. Pancreatic enzyme replacement therapy (PERT) has been shown to be effective in improving nutritional status and subsequently associated with improved lung function. However, the timings of PERT administration in relation to a meal are subjective and not standardised, meaning that variations in the timing of PERT dosing persist.

OBJECTIVES

The primary objective of the review is to compare the efficacy (fat absorption) and effectiveness (nutritional status, lung function and quality of life) of different PERT dosing strategies in terms of timing of administration for treating dietary malabsorption in all individuals with CF.

SEARCH METHODS

We searched the Cochrane Cystic Fibrosis Trials Register, compiled from electronic database searches and handsearching of journals and conference abstract books. We also searched the reference lists of relevant articles and reviews. Date of last search: 24 June 2021. We also searched ongoing trials registers on 09 July 2021.

SELECTION CRITERIA

Randomised controlled trials (RCTs), including cross-over RCTs with a minimum washout period of two weeks, and quasi-RCTs of PERT dosing regimens in people (of any age) with CF.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed and screened the studies identified from the searches. We planned to use GRADE to assess the certainty of evidence for our pre-specified critical outcomes, but we did not identify any eligible studies.

MAIN RESULTS

No studies met the eligibility criteria and therefore we did not include any in this review. The excluded studies were either cross-over in design (but lacking a sufficient washout period between treatments) or did not assess the timing of PERT. One study which was terminated early is awaiting assessment pending further information.

AUTHORS' CONCLUSIONS

We were unable to determine whether one dosing schedule for PERT is better than another since we identified no eligible RCTs. While the introduction of PERT to people with CF can improve their nutritional status, there are a limited number of studies which address this review question, and none met our eligibility criteria. Since malnutrition and adverse gastrointestinal symptoms remain a common feature in CF, the assessment of the relative performance of dosing schedules may provide evidence to improve outcomes in people with CF who are pancreatic insufficient. Further research is needed to fully evaluate the role of dosing schedules for PERT in fat absorption. Research should also establish reliable outcome measures and minimal clinically important differences. While RCTs with a cross-over design may have advantages over a parallel group design, an adequate washout period between intervention periods is essential.

Acute Pancreatitis in a Previously Exocrine Pancreatic Insufficient Cystic Fibrosis Patient Who Had Improved Pancreatic Function After Being Treated With Lumacaftor/Ivacaftor

Exocrine pancreatic insufficiency (EPI) is a common complication of cystic fibrosis (CF). While previously considered to be irreversible, recent reported cases document improved pancreatic function in CF patients with mild mutations after ivacaftor treatment alone. We report a 12-year-old female with homozygous F508del CF and EPI who developed acute pancreatitis after 3 years on lumacaftor/ivacaftor and subsequently had improved pancreatic function. As CF therapies advance, some EPI CF patients with more severe CF transmembrane conductance regulator mutations may see improved pancreatic function and subsequently develop pancreatitis.

Cystic fibrosis

Cystic fibrosis is a monogenic disease considered to affect at least 100 000 people worldwide. Mutations in CFTR, the gene encoding the epithelial ion channel that normally transports chloride and bicarbonate, lead to impaired mucus hydration and clearance. Classical cystic fibrosis is thus characterised by chronic pulmonary infection and inflammation, pancreatic exocrine insufficiency, male infertility, and might include several comorbidities such as cystic fibrosis-related diabetes or cystic fibrosis liver disease. This autosomal recessive disease is diagnosed in many regions following newborn screening, whereas in other regions, diagnosis is based on a group of recognised multiorgan clinical manifestations, raised sweat chloride concentrations, or CFTR mutations. Disease that is less easily diagnosed, and in some cases affecting only one organ, can be seen in the context of gene variants leading to residual protein function. Management strategies, including augmenting mucociliary clearance and aggressively treating infections, have gradually improved life expectancy for people with cystic fibrosis. However, restoration of CFTR function via new small molecule modulator drugs is transforming the disease for many patients. Clinical trial pipelines are actively exploring many other approaches, which will be increasingly needed as survival improves and as the population of adults with cystic fibrosis increases. Here, we present the current understanding of CFTR mutations, protein function, and disease pathophysiology, consider strengths and limitations of current management strategies, and look to the future of multidisciplinary care for those with cystic fibrosis.

Exocrine pancreas insufficiency: clinical significance and approaches to correction from evidence medicine

Exocrine pancreatic insufficiency (EPI) is a common complication of both benign and malignant diseases of the pancreas, as well as a consequence of radical surgical operations on the pancreas and a whole range of other variable extra-pancreatic causes. In clinical practice in the adult population, most cases of EPI are associated with chronic pancreatitis, while in the pediatric population with cystic fibrosis. The regression of the production of digestive enzymes in EPI mediates the development of the syndrome of maldigestion and malabsorption, leading to the progressive development of malnutrition, the importance of which is often underestimated by practitioners. At the same time, the development of nutritional deficiency is not just a complication of EPI, but also has an important effect on the course of the underlying causative disease, worsening the prognosis and quality of life of the patient, and is also a proven risk factor for osteoporosis and sarcopenia. To date, compensation for the absolute deficiency of pancreatic enzymes using enzyme replacement therapy is the only possible way to correct the EPI and prevent nutritional deficiency.

Animal Models and Their Role in Understanding the Pathophysiology of Cystic Fibrosis-Associated Gastrointestinal Lesions

The life expectancy of cystic fibrosis (CF) patients has greatly increased over the past decade, and researchers and clinicians must now navigate complex disease manifestations that were not a concern prior to the development of modern therapies. Explosive growth in the number of CF animal models has also occurred over this time span, clarifying CF disease pathophysiology and creating opportunities to understand more complex disease processes associated with an aging CF population. This review focuses on the CF-associated pathologies of the gastrointestinal system and how animal models have increased our understanding of this complex multisystemic disease. Although CF is primarily recognized as a pulmonary disease, gastrointestinal pathology occurs very commonly and can affect the quality of life for these patients. Furthermore, we discuss how next-generation genetic engineering of larger animal models will impact the field's understanding of CF disease pathophysiology and the development of novel therapeutic strategies.

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 (CFTR^tm1HGU ) 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 CFTR^tm1HGU 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 CFTR^tm1HGU did not differ from controls. Fluid and bicarbonate secretion were greatly impaired, whereas faecal chymotrypsin remained unchanged. LPS stimulation of splenocytes from CFTR^tm1HGU 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.

Cystic fibrosis-related diabetes onset can be predicted using biomarkers measured at birth

Purpose

Cystic fibrosis (CF), caused by pathogenic variants in the CF transmembrane conductance regulator (CFTR), affects multiple organs including the exocrine pancreas, which is a causal contributor to cystic fibrosis–related diabetes (CFRD). Untreated CFRD causes increased CF-related mortality whereas early detection can improve outcomes.

Methods

Using genetic and easily accessible clinical measures available at birth, we constructed a CFRD prediction model using the Canadian CF Gene Modifier Study (CGS; n = 1,958) and validated it in the French CF Gene Modifier Study (FGMS; n = 1,003). We investigated genetic variants shown to associate with CF disease severity across multiple organs in genome-wide association studies.

Results

The strongest predictors included sex, CFTR severity score, and several genetic variants including one annotated to PRSS1, which encodes cationic trypsinogen. The final model defined in the CGS shows excellent agreement when validated on the FGMS, and the risk classifier shows slightly better performance at predicting CFRD risk later in life in both studies.

Conclusion

We demonstrated clinical utility by comparing CFRD prevalence rates between the top 10% of individuals with the highest risk and the bottom 10% with the lowest risk. A web-based application was developed to provide practitioners with patient-specific CFRD risk to guide CFRD monitoring and treatment.

Critical thresholds: key to unlocking the door to the prevention and specific treatments for acute pancreatitis

Acute pancreatitis (AP), an acute inflammatory disorder of the exocrine pancreas, is one of the most common gastrointestinal diseases encountered in emergency departments with no specific treatments. Laboratory-based research has formed the cornerstone of endeavours to decipher the pathophysiology of AP, because of the limitations of such study in human beings. While this has provided us with substantial understanding, we cannot answer several pressing questions. These are: (a) Why is it that only a minority of individuals with gallstones, or who drink alcohol excessively, or are exposed to other causative factors develop AP? (b) Why do only some develop more severe manifestations of AP with necrosis and/or organ failure? (c) Why have we been unable to find an effective therapeutic for AP? This manuscript provides a state-of-the-art review of our current understanding of the pathophysiology of AP providing insights into the unanswered clinical questions. We describe multiple protective factors operating in most people, and multiple stressors that in a minority induce AP, independently or together, via amplification loops. We present testable hypotheses aimed at halting progression of severity for the development of effective treatments for this common unpredictable disease.

Paediatric pancreatic diseases

Paediatric pancreatic diseases are often under-recognised and may be associated with severe diseases and significant clinical consequences. In recent years, advances have been made in key areas, particularly with the contributions from international societies and study groups focused on paediatric pancreatic disease research. This review focuses on the two key manifestations of pancreatic disorders in childhood, pancreatitis and exocrine pancreatic dysfunction.

Cystic fibrosis and the gut

Cystic fibrosis (CF) is a recessive disease caused by mutations in the CF transmembrane conductance regulator (CFTR) gene. The gene product, CFTR protein, has important manifestations in the intestine, pancreas and hepatobiliary system. Increased survival has caused CF to be primarily an adult disease today. Physicians must be knowledgeable as to the varied phenotype in the gastrointestinal tract. This review will outline the main gastrointestinal manifestations including a section on gastrointestinal malignancy in CF. Novel treatments treating the basic effect in CF are now being introduced and their effects on the gastrointestinal tract are discussed.

Pancreatic complications in children with cystic fibrosis

PURPOSE OF REVIEW

The pancreas is highly affected in cystic fibrosis, with complications occurring early in childhood. This review highlights recent research in exocrine pancreatic function in the era of cystic fibrosis transmembrane conductance regulator (CFTR) modulator therapies and discusses how these are affecting pancreatitis and exocrine pancreatic insufficiency (EPI) in children. Additionally, new research into exocrine--endocrine interactions sheds light on how CFTR dysfunction in ductal cells may affect beta cells.

RECENT FINDINGS

Ivacaftor has disproved the hypothesis that EPI in children with cystic fibrosis is irreversible. Improvements in pancreatic function have increased pancreatitis episodes in some children and reduced them in others. Imaging advances are providing complementary methods for exocrine pancreatic function testing. New research into the interplay between the exocrine and endocrine components of the pancreas are elucidating the intertwined and complex relationship between the exocrine and endocrine pancreas.

SUMMARY

Pancreatic complications contribute to the morbidity and mortality of children with cystic fibrosis. Increasing use of highly effective CFTR modulators will not only abrogate these but will also advance our understanding of pancreatic pathophysiology in cystic fibrosis. New frontiers into pancreatic gene therapy and exocrine--endocrine research will help provide new therapeutic opportunities for pancreatitis, EPI, and diabetes in cystic fibrosis.