Cystic Fibrosis & disorders of the large intestine: DIOS, constipation, and colorectal cancer

Presentation, characteristics and management of obstructive intestinal conditions in cystic fibrosis

Objective

Constipation and distal intestinal obstruction syndrome (DIOS) are common gastrointestinal manifestations of cystic fibrosis (CF). The primary aim was to describe the characteristics of constipation and DIOS hospitalisations in a paediatric and adult CF service over a 12-year period. The secondary aims were to determine the proportion of constipation and DIOS presentations which met the European Society for Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) CF Working Group definitions and to describe management strategies of both conditions.

Method

A retrospective study of children and adults with CF who were admitted with a primary diagnosis of constipation or DIOS between 1 January 2011 and 31 December 2022. ESPGHAN definitions for constipation and DIOS were retrospectively applied to all admissions to determine if the primary medical diagnosis met ESPGHAN criteria.

Results

During the 12-year study period, 42 hospitalisations for constipation were recorded in 19 patients, and 33 hospitalisations for DIOS were recorded in 23 patients. 88.10% of constipation episodes met ESPGHAN definitions, compared with 3.0% of DIOS episodes. Constipation and DIOS were primarily treated with polyethylene glycol (PEG). The use of sodium amidotrizoate meglumine enemas was significantly higher in the DIOS group (p=0.045). Those admitted with DIOS were significantly less likely to be recommended a weaning dose of PEG (p=0.018).

Conclusion

Children and adults with CF are more commonly admitted for the management of constipation than DIOS. There is considerable variation in diagnostic and therapeutic practice, and this study highlights the need to enhance the translation and adoption of existing best-practice guidelines.

Gastrointestinal Pathologies in Pediatric Patients With Cystic Fibrosis Undergoing Endoscopy: A Single-Center Retrospective Review Over 15 Years

Introduction Previous studies have demonstrated an increased incidence of gastrointestinal (GI) pathologies, specifically celiac disease (CD) and eosinophilic esophagitis (EoE), in patients with cystic fibrosis (CF). However, there is minimal data available regarding endoscopic findings in pediatric patients with CF and GI mucosal disease.  Methods A retrospective chart review was performed on patients with CF under 18 years of age who underwent esophagogastroduodenoscopy (EGD) or colonoscopy with biopsy over a 15-year period at our institution. Patient characteristics including assigned sex at birth, CF genetic mutations (if identified), and cystic fibrosis transmembrane conductance regulator (CFTR) modulator use were recorded. Data obtained at the time of biopsy included body mass index (BMI), indication for the procedure, exocrine pancreatic status, visual endoscopic findings, and histologic findings. Results A total of 72 patients with CF were included in the study. 24% (n=17) were found to have abnormal endoscopic biopsy results. EoE (13% of all patients, n=9) and CD (6% of all patients, n=4) were the most common GI diagnoses present on endoscopic biopsy. All 3 patients taking CFTR modulator medications at the time of endoscopy had normal biopsy results. Of the 17 patients found to have abnormal pathology results, 14 (82%) were taking proton-pump inhibitor (PPI) medication at the time of endoscopy. Conclusion This study highlights the probable increased frequency of GI disease in the pediatric CF population. These findings underscore the importance of maintaining a broad differential diagnosis while considering utilization of endoscopy with biopsy in pediatric patients with CF who have GI symptoms.

Diagnosis and Management of Gastrointestinal Manifestations in Children with Cystic Fibrosis

Cystic fibrosis (CF) is primarily known for its pulmonary consequences, which are extensively explored in the existing literature. However, it is noteworthy that individuals with CF commonly display gastrointestinal (G-I) manifestations due to the substantial presence of the cystic fibrosis transmembrane conductance regulator (CFTR) protein in the intestinal tract. Recognized as pivotal nonpulmonary aspects of CF, G-I manifestations exhibit a diverse spectrum. Identifying and effectively managing these manifestations are crucial for sustaining health and influencing the overall quality of life for CF patients. This review aims to synthesize existing knowledge, providing a comprehensive overview of the G-I manifestations associated with CF. Each specific G-I manifestation, along with the diagnostic methodologies and therapeutic approaches, is delineated, encompassing the impact of innovative treatments targeting the fundamental effects of CF on the G-I tract. The findings underscore the imperative for prompt diagnosis and meticulous management of G-I manifestations, necessitating a multidisciplinary team approach for optimal care and enhancement of the quality of life for affected individuals. In conclusion, the authors emphasize the urgency for further clinical studies to establish a more robust evidence base for managing G-I symptoms within the context of this chronic disease. Such endeavors are deemed essential for advancing understanding and refining the clinical care of CF patients with G-I manifestations.

Potential systemic effects of acquired CFTR dysfunction in COPD

Chronic obstructive pulmonary disease (COPD) is characterized by airflow limitation, respiratory symptoms, inflammation of the airways, and systemic manifestations of the disease. Genetic susceptibility and environmental factors are important in the development of the disease, particularly exposure to cigarette smoke which is the most notable risk factor. Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene are the cause of cystic fibrosis (CF), which shares several pathophysiological pulmonary features with COPD, including airway obstruction, chronic airway inflammation and bacterial colonization; in addition, both diseases also present systemic defects leading to comorbidities such as pancreatic, gastrointestinal, and bone-related diseases. In patients with COPD, systemic CFTR dysfunction can be acquired by cigarette smoking, inflammation, and infection. This dysfunction is, on average, about half of that found in CF. Herein we review the literature focusing on acquired CFTR dysfunction and the potential role in the pathogenesis of comorbidities associated with COPD and chronic bronchitis.

Cystic Fibrosis and Cancer: Unraveling the Complex Role of CFTR Gene in Cancer Susceptibility

Cystic fibrosis (CF) is a genetic disorder affecting multiple organs, primarily the lungs and digestive system. Over the years, advancements in medical care and treatments have significantly increased the life expectancy of individuals with CF. However, with this improved longevity, concerns about the potential risk of developing certain types of cancers have arisen. This narrative review aims to explore the relationship between CF, increased life expectancy, and the associated risk for cancers. We discuss the potential mechanisms underlying this risk, including chronic inflammation, immune system dysregulation, and genetic factors. Additionally, we review studies that have examined the incidence and types of cancers seen in CF patients, with a focus on gastrointestinal, breast, and respiratory malignancies. We also explore the impact of CFTR modulator therapies on cancer risk. In the gastrointestinal tract, CF patients have an elevated risk of developing colorectal cancer, pancreatic cancer, and possibly esophageal cancer. The underlying mechanisms contributing to these increased risks are not fully understood, but chronic inflammation, altered gut microbiota, and genetic factors are believed to play a role. Regular surveillance and colonoscopies are recommended for early detection and management of colorectal cancer in CF patients. Understanding the factors contributing to cancer development in CF patients is crucial for implementing appropriate surveillance strategies and improving long-term outcomes. Further research is needed to elucidate the molecular mechanisms involved and develop targeted interventions to mitigate cancer risk in individuals with CF.

Thinking outside the box: a review of gastrointestinal symptoms and complications in cystic fibrosis

INTRODUCTION

Gastrointestinal (GI)-related symptoms, complications, and comorbidities in cystic fibrosis (CF) are common and research to reduce their burden is a priority for the CF community. To enable future research, this review aimed to summarize the range of GI symptoms, complications and comorbidities seen in CF, the underlying pathophysiology, and treatments.

AREAS COVERED

This was a rapid systematic review undertaken using the recommendations from the Cochrane Rapid Reviews Methods Group. We searched databases including PubMed, Embase, Medline and the Cochrane database and identified those studies reporting GI-related symptoms, complications, or comorbidities in CF or their treatment. Our searches identified 2,930 studies and a total 119 studies met our inclusion criteria. Where a prevalence could be determined, GI symptoms were reported in 33.7% of study participants. The range of symptoms reported was broad and the highest median prevalence included flatulence (43.5%), bloating and abdominal distension (36%), and fatty stool (36%). Meconium ileus was reported in 12% and distal intestinal obstruction syndrome in 8.5.

EXPERT OPINION

GI-related symptoms, complications, and comorbidities in CF are common. More consistent characterization and recording of these symptoms in clinical studies may help achieve the priority of reducing the burden of GI disease in CF.

CFTR high expresser cells in cystic fibrosis and intestinal diseases

Cystic Fibrosis Transmembrane Conductance Regulator (CFTR), the Cl^-/HCO₃ ^- channel implicated in Cystic Fibrosis, is critical to the pathophysiology of many gastrointestinal diseases. Defects in CFTR lead to intestinal dysfunction, malabsorption, obstruction, infection, inflammation, and cancer that increases morbidity and reduces quality of life. This review will focus on CFTR in the intestine and the implications of the subpopulation of CFTR High Expresser Cells (CHEs) in Cystic Fibrosis (CF), intestinal physiology and pathophysiology of intestinal diseases.

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.

Distal Intestinal Obstruction Syndrome Relieved by Ileoscopy in a Patient With Cystic Fibrosis: A Case Report and Literature Review

Distal intestinal obstruction syndrome (DIOS) is a common complication in patients with cystic fibrosis (CF). Patients typically present with right lower quadrant pain, nausea, abdominal distention, and failure to pass stool or flatus. It can be managed conservatively with medical interventions but some cases may require colonoscopy and even surgery. We report a rare instance in which a CF patient with a previous ileostomy developed DIOS and was successfully managed with ileoscopy after medical management failed.

Abdominal Surgical Procedures in Adult Patients With Cystic Fibrosis: What Are the Risks?

BACKGROUND

With advances in medical care, patients with cystic fibrosis are more commonly living into adulthood, yet there are limited data describing the need for GI surgery and its outcomes in adult cystic fibrosis patients.

OBJECTIVE

We aim to use a national administrative database to evaluate trends in abdominal GI surgery and associated postoperative outcomes among adult cystic fibrosis patients.

DESIGN

This was a national retrospective cohort study.

SETTING

A national all-payor administrative database from 2000 to 2014 was used.

PATIENTS

Patients included adults (age ≥18 years) with cystic fibrosis undergoing abdominal GI surgery.

MAIN OUTCOME MEASURES

The primary outcome was trend over time in number of surgical admissions. Secondary outcomes included morbidity and mortality by procedure type.

RESULTS

We identified 3075 admissions for abdominal surgery, of which 28% were elective. Major GI surgical procedures increased over the study period ( p < 0.01), whereas appendectomy and cholecystectomy did not demonstrate a clear trend ( p = 0.90). The most common procedure performed was cholecystectomy ( n = 1280; 42%). The most common major surgery was segmental colectomy ( n = 535; 18%). Obstruction was the most common surgical indication ( n = 780; 26%). For major surgery, in-hospital mortality was 6%, morbidity was 37%, and mean length of stay was 15.9 days (SE 1.2).

LIMITATIONS

The study is limited by a lack of granular physiological and clinical data within the administrative data source.

CONCLUSIONS

Major surgical admissions for adult patients with cystic fibrosis are increasing, with the majority being nonelective. Major surgery is associated with significant morbidity, mortality, and prolonged length of hospital stay. These findings may inform perioperative risk for adult patients with cystic fibrosis in need of GI surgery. See Video Abstract at http://links.lww.com/DCR/B850 .

PROCEDIMIENTOS QUIRRGICOS ABDOMINALES EN PACIENTES ADULTOS CON FIBROSIS QUSTICA CULES SON LOS RIESGOS

ANTECEDENTES:Con los avances en la medicina, los pacientes con fibrosis quística viven más comúnmente hasta la edad adulta, pero hay datos escasos que describan la necesidad de cirugía gastrointestinal y sus resultados en pacientes adultos con fibrosis quística.OBJETIVO:Nuestro objetivo es utilizar una base de datos administrativa nacional para evaluar las tendencias en la cirugía gastrointestinal abdominal y los resultados posoperatorios asociados entre los pacientes adultos con fibrosis quística.DISEÑO:Estudio de cohorte retrospectivo nacional.AJUSTE:Base de datos administrativa nacional de todas las instituciones pagadoras desde 2000 a 2014.PACIENTES:Todos los pacientes adultos (edad> 18) con fibrosis quística sometidos a cirugía gastrointestinal abdominal.PRINCIPALES MEDIDAS DE RESULTADO:El resultado primario fue la tendencia a lo largo del tiempo en el número de ingresos quirúrgicos. Los resultados secundarios incluyeron morbilidad y mortalidad por tipo de procedimiento.RESULTADOS:Identificamos 3.075 ingresos por cirugía abdominal de los cuales el 28% fueron electivos. Los procedimientos quirúrgicos gastrointestinales mayores aumentaron durante el período de estudio (p <0,01) mientras que la apendicectomía y la colecistectomía no demostraron una tendencia clara (p = 0,90). El procedimiento realizado con mayor frecuencia fue la colecistectomía (n = 1.280; 42%). La cirugía mayor más común fue la colectomía segmentaria (n = 535; 18%). La obstrucción fue la indicación quirúrgica más común (n = 780; 26%). Para la cirugía mayor, la mortalidad hospitalaria fue del 6%, la morbilidad del 37% y la estadía media de 15,9 días (EE 1,2).LIMITACIONES:El estudio está limitado por la falta de datos clínicos y fisiológicos granulares dentro de la fuente de datos administrativos.CONCLUSIONES:Los ingresos quirúrgicos mayores de pacientes adultos con fibrosis quística están aumentando y la mayoría no son electivos. La cirugía mayor se asocia con una morbilidad y mortalidad significativas y una estancia hospitalaria prolongada. Estos hallazgos pueden informar el riesgo perioperatorio para pacientes adultos con fibrosis quística que necesitan cirugía gastrointestinal. Consulte Video Resumen en http://links.lww.com/DCR/B850 . (Traducción-Dr. Felipe Bellolio ).

Children With Cystic Fibrosis Have Elevated Levels of Fecal Chitinase-3-like-1

Although chitinase-3-like-1 (CHI3L1), predominately produced by epithelial cells and macrophages, is relevant to pulmonary disease in cystic fibrosis (CF), fecal levels have not yet been assessed in children with CF. Fecal CHI3L1 was measured with a commercial immunoassay using fecal samples provided by children with CF and healthy control (HC) children. Higher median (interquartile range) fecal CHI3L1 levels were seen in the 52 children with CF than in the 35 controls: 15.97 (3.34-50.53) ng/g versus 2.93 (2.13-9.27) ng/g ( P = 0.001). Fecal CHI3LI did not differ according to sex. In the children with CF, fecal CHI3L1 levels did not correlate with growth parameters nor were the levels affected by pancreatic insufficiency. Children with CF had higher fecal CHI3L1 levels, suggesting underlying gut inflammation. Further work is required to confirm the current findings and to ascertain the longer-term significance of elevated CHI3L1.

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.

Small bowel water content assessed by MRI in health and disease: a collation of single-centre studies

BACKGROUND

New developments in MRI have allowed the non-invasive, accurate measurement of the small bowel water content (SBWC).

AIMS

To collate studies measuring SBWC following ingestion of a range of foods in both health and disease to provide data for adequately powering future studies in this area.

METHODS

This collation brings together 29 studies including 954 participants (530 healthy, 54 diverticulosis, 255 IBS, 53 functional constipation, 12 cystic fibrosis, 15 Crohn's disease, 20 coeliac disease, 15 scleroderma) which have been carried out in a single centre using comparable study designs.

RESULTS

Fasting SBWC (mean 82 [SD 65] mL) shows high variability with a small decline with advancing age (healthy volunteers only; individual patient data). Fasting values are increased in untreated coeliac disease (202 [290] mL, P = 0.004). Post-prandial SBWC shows less intra-individual variability than fasting values in healthy volunteers. SBWC is increased by eating, most markedly by high fat meals but also by fibre, both viscous and particulate. Indigestible residue accumulates in late post-prandial period but empties soon after ingestion of a high calorie meal which produces a significant drop (by 50 [52] mL) in healthy volunteers. The associated fall in SBWC is abnormal in people with cystic fibrosis (SBWC reduced by 10 [121] mL, P = 0.002) and in people with irritable bowel syndrome with diarrhoea (SBWC reduced by 17 [43] mL, P = 0.007).

CONCLUSIONS

SBWC as assessed by MRI is a valuable biomarker indicating the balance of secretion and absorption in health and disease and the impact of treatments.

Malignancies in patients with cystic fibrosis: a case series

Background

Previous reports have shown an increased number of colorectal cancers in patients with cystic fibrosis. We assessed the database of our cystic fibrosis center to identify patients with all kinds of cancer retrospectively. All patients visiting the Cystic Fibrosis Centre Innsbruck between 1995 and 2019 were included.

Case presentation

Among 229 patients with cystic fibrosis treated at the Cystic Fibrosis Centre in Innsbruck between 1995 and 2019, 11 subjects were diagnosed with a malignant disease. The median age at diagnosis was 25.2 years (mean 24.3 years). There were four gynecological malignancies (cervical intraepithelial neoplasia and cervical cancer), two hematological malignancies (acute lymphocytic leukemia), one gastrointestinal malignancy (peritoneal mesothelioma), and four malignancies from other origins (malignant melanoma, neuroblastoma, adrenocortical carcinoma, and thyroid cancer). One malignancy occurred after lung transplantation. There was a strong preponderance of females, with 10 of the 11 cases occurring in women. Six deaths were attributed to cancer.

Conclusions

Most diagnoses were made below 30 years of age, and half of the subjects died from the malignant disease. Awareness of a possible malignancy is needed in patients with atypical symptoms. Regular screenings for cancer should also be considered, not only for gastrointestinal tumors.

Colonic Transit Time and Fecal Impaction in Children and Adolescents With Cystic Fibrosis-associated Constipation

BACKGROUND

Constipation is prevalent in pediatric cystic fibrosis (CF) patients and colonic motility has not been studied in this population. In this study, we aimed to evaluate the total and segmental colonic transit time in children and adolescents with CF based on the presence of constipation and radiological fecal impaction.

METHODS

In this case series, all patients aged 3 to 20 years of a CF reference center were invited to participate. CF-associated constipation was diagnosed based on the European Society for Paediatric Gastroenterology Hepatology and Nutrition criteria. Total and segmental colonic transit time was determined using radiopaque markers. Fecal impaction on plain abdominal radiography was assessed based on the Barr score.

RESULTS

Of the 43 eligible patients, 34 (79%) agreed to participate. Constipation was found in 44.1% of children and adolescents, predominantly in girls. The total colonic transit time (medians of 42 and 24 hours, respectively, P = 0.028) and the segmental right colon transit time (medians of 8 and 2 hours, respectively, P = 0.012) were significantly longer in CF-associated constipation group than in the group of patients without constipation. The frequency of radiological fecal impaction was similar in patients with (50.0%) and without (64.2%) CF-associated constipation (P = 0.70). There was no relationship between radiological fecal impaction and the total and segmental colonic transit time.

CONCLUSIONS

Children and adolescents with CF-associated constipation had a longer total and segmental right colon transit time. Colonic transit time was similar in patients with and without radiological fecal impaction.

Postprandial changes in gastrointestinal function and transit in cystic fibrosis assessed by Magnetic Resonance Imaging

BACKGROUND

Cystic fibrosis (CF) is a multi-system genetic disorder affecting >72,000 people worldwide. Most CF patients experience gastrointestinal symptoms and can develop complications. However, the mechanisms of CF gut disease are not well understood. We evaluated gut function and transit in CF using magnetic resonance imaging (MRI). We hypothesised oro-caecal transit time (OCTT) is longer in CF; with lower small bowel water content (SBWC).

METHODS

Twelve CF patients aged 12-40 years and 12 age and sex-matched controls underwent serial MRIs over 1 day with standardised meals. The primary endpoint was OCTT, assessed by the appearance of a food bolus in the caecum. Other measures included corrected SBWC and corrected colonic volume (both area under the curve, AUC), gastric half-emptying time and gastrointestinal symptoms.

RESULTS

OCTT was longer in CF (CF 330 mins [270, >360] vs. controls 210 mins [173, 315], p = 0.04), with no difference in gastric half-emptying times. Corrected SBWC was higher in CF (CF 62 L.min/m2 [36, 80] vs. controls 34 L.min/m2 [28, 41], p = 0.021); minimal postprandial decrease between T240 and T300 (CF 13 mL/m2 [-13, 57] vs. controls 102 mL/m2 [67, 108], p = 0.002) suggests impaired ileal emptying. Corrected colonic volumes were higher in CF (CF 186 L.min/m2 [167, 206] vs. controls 123 L.min/m2 [89, 146], p = 0.012). There were no differences in gastrointestinal symptoms.

CONCLUSIONS

MRI provides novel insights into CF pathophysiology. Sub-clinical ileal obstruction may be more prevalent than previously thought. Gastrointestinal MRI shows promise as an investigational tool in CF.

Luminal Gastrointestinal Manifestations of Cystic Fibrosis

PURPOSE OF REVIEW

People with cystic fibrosis (CF) are living longer. General age-related and CF-specific gastrointestinal symptoms are increasingly recognized. In this article, we review the latest data on luminal gastrointestinal manifestations in CF.

RECENT FINDINGS

People with CF have increased incidence of gastroesophageal reflux disease symptoms and often prescribed proton-pump inhibitors (PPI). PPI use may increase risk of pulmonary exacerbations. Evidence to support gastric fundoplication to improve pulmonary outcomes is limited. Features of intestinal dysmotility are common. There are distinct differences in the gut microbiome in the CF population which may have clinical implications. CF is a possible hereditary digestive cancer syndrome, particularly in regard to colorectal cancer (CRC) with earlier incidence of CRC and advanced colonic neoplasia. Early screening colonoscopy is warranted in the CF population. Gastrointestinal manifestations in CF are prevalent across all digestive organs. More study on the effect of interventions for symptomatic treatment and cancer screening is needed.

Inhibition of Na+ /H+ exchanger isoform 3 improves gut fluidity and alkalinity in cystic fibrosis transmembrane conductance regulator-deficient and F508del mutant mice

BACKGROUND AND PURPOSE

Constipation and intestinal obstructive episodes are major health problems in cystic fibrosis (CF) patients. Three FDA-approved drugs against constipation-prone irritable bowel syndrome were tested for their ability to increase luminal fluidity and alkalinity in cystic fibrosis transmembrane conductance regulator (CFTR) null (cftr^-/- ) and F508del mutant (F508del^mut/mut ) murine intestine.

EXPERIMENTAL APPROACH

Guanylate cyclase C agonist linaclotide, PGE₁ analogue lubiprostone and intestine-specific NHE3 inhibitor tenapanor were perfused through a ~3 cm jejunal, proximal or mid-distal colonic segment in anaesthetized cftr^-/- , F508del^mut/mut and WT mice. Net fluid balance was determined gravimetrically and alkaline output by pH-stat back titration.

KEY RESULTS

Basal jejunal fluid absorptive rates were significantly higher and basal HCO₃ ^- output was significantly lower in cftr^-/- and F508del^mut/mut compared to WT mice. In cftr^-/- and F508del^mut/mut mice, all three drugs significantly inhibited the fluid absorptive rate and increased alkaline output in the jejunum and tenapanor and lubiprostone, but not linaclotide, in the colon. After tenapanor pre-incubation, linaclotide elicited a robust fluid secretory response in WT jejunum, while no further change in absorptive rates was observed in cftr^-/- and F508del^mut/mut jejunum, suggesting that the increase in gut fluidity and alkalinity by linaclotide in CF gut is mediated via NHE3 inhibition. Lubiprostone also inhibited fluid absorption in cftr^-/- and F508del^mut/mut jejunum via NHE3 inhibition but had a residual NHE3-independent effect.

CONCLUSION AND IMPLICATIONS

Linaclotide, lubiprostone and tenapanor reduced fluid absorption and increased alkaline output in the CF gut. Their application may ameliorate constipation and reduce obstructive episodes in CF patients.

Designing the GALAXY study: Partnering with the cystic fibrosis community to optimize assessment of gastrointestinal symptoms

BACKGROUND

Gastrointestinal (GI) involvement among persons with cystic fibrosis (CF) is highly prevalent, representing a significant source of morbidity. Persons with CF have identified GI concerns as a top research priority, yet universal clinical outcome measures capturing many of the GI symptoms experienced in CF are lacking. The GALAXY study was envisioned to address this unmet need.

METHODS

The GALAXY study team partnered with Community Voice, a community of patients with CF and their caregivers, to identify the patient reported outcome measures that most accurately reflected their experience with GI symptoms in CF. We also surveyed CF care teams to identify the comfort level of various team members (providers, nurses and dieticians) in managing a variety of GI conditions.

RESULTS

Members of Community Voice identified the combination of PAC-SYM, PAGI-SYM, PAC-QOL and the Bristol Stool scale with three additional symptom-specific questions as patient-reported outcome measures that comprehensively captured the CF experience with GI disease. CF care team providers reported a high level of comfort in treating GI conditions including constipation (92%), GERD (93%), and gassiness (77%), however comfort level was limited to only first-line interventions.

CONCLUSION

By partnering with persons with CF as well as their caregivers and medical providers, the GALAXY study is designed to uniquely capture the prevalence and severity of GI involvement among persons with CF in a manner that reflects the CF patient experience. The results of GALAXY will inform the development of future interventional trials and serve as a reproducible and objective study endpoint.

Proximal intestinal obstruction syndrome (PIOS) in a patient with cystic fibrosis: A case report

Introduction

Distal Intestinal Obstruction Syndrome is a rare complication in patients with cystic fibrosis, which characterized by the accumulation of viscid fecal material, combined with sticky mucous secretions located in the distal ileum adhere to the intestinal wall, causing complete bowel obstruction.

Presentation of case

We report a case of a 45 years old patient with cystic fibrosis, who presented bowel obstruction secondary to accumulation of fecal material, combined with mucous secretions, in the mid-jejunum. A diagnostic laparoscopy was performed where a dilated jejunum was encountered with impaction of fecal content. Surgery was converted to open surgery, where a longitudinal enterotomy of 5 cm after the transition zone was created, evacuating manually the fecal material with mucous secretion. The patient evolved favorably, without complications.

Discussion

We present a case of a patient with cystic fibrosis presenting with bowel obstruction due to a proximal intestinal obstruction syndrome, which can be diagnosed with the DIOS definition, with the only distinction of a more proximal location in the gastrointestinal tract, such as the stomach, the duodenum, or the jejunum.

Conclusion

It is important for the clinician to know the existence of this syndrome at its different locations in the small bowel to treat accordingly.

•

Proximal Intestinal Obstruction Syndrome is a rare complication in patients with cystic fibrosis.

•

It is the accumulation of viscid feces with mucous secretions in the small bowel.

•

It is important to know the existence of this syndrome to treat accordingly.

Rapidly progressive metastatic cholangiocarcinoma in a postpartum patient with cystic fibrosis: a case report

BACKGROUND

Cholangiocarcinoma is a rare gastrointestinal malignancy that arises within the intrahepatic, perihilar, and/or extrahepatic bile ducts. Individuals with cystic fibrosis are at increased risk for gastrointestinal malignancies. The most common gastrointestinal malignancy in cystic fibrosis is colon cancer, but other gastrointestinal malignancies also occur at greater rates than the general population.

CASE PRESENTATION

We present a case of a rapidly progressive metastatic intrahepatic cholangiocarcinoma in an individual with cystic fibrosis who was 5 months postpartum, incidentally found while undergoing a lung transplantation evaluation.

CONCLUSION

A heightened clinical awareness of gastrointestinal malignancies, beyond colon cancer, in individuals with cystic fibrosis is warranted. It remains unclear if pregnancy is an additional risk factor for gastrointestinal malignancies in cystic fibrosis.

Prevalence of constipation in cystic fibrosis patients: a systematic review of observational studies

OBJECTIVE

To systematically revise the literature in search of data about the prevalence of constipation in patients with cystic fibrosis according to the publications in this field, which partly refer to guidelines defined in 2010 by the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition.

SOURCES

Systematic review selecting articles based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, including Cystic Fibrosis patients of all ages. Sources of information were selected to identify the articles without period limitation: CADTH - Canadian Agency for Drugs and Technologies in Health, CINAHL Complete, Clinical Trials US NIH, Cochrane Library, Embase, MEDLINE via Ovid, Scopus, Web Of Science, PubMed, SciELO, MEDLINE and LILACS , Health Systems Evidence, PDQ Evidence, CRD Canadian Agency for Drugs and Technologies in Health, INAHTA - International Network of Agencies for Health Technology Assessment, and PEDro.

FINDINGS

The prevalence of constipation was reported in eight observational studies. Only two studies assessed the frequency of constipation as a primary objective; in the others, constipation was quoted along with the prevalence of the spectrum of gastrointestinal manifestations. Altogether, the publications included 2,018 patients, the reported prevalence varied from 10% to 57%. Only two of the six articles published after 2010 followed the definition recommended by the European Society.

CONCLUSIONS

Constipation is a frequent but still insufficiently assessed complaint of Cystic Fibrosis patients. The use of diverse diagnostic criteria restricts comparison and epidemiological conclusions, future studies should compulsorily apply the European Society for Pediatric Gastroenterology, Hepatology, and Nutrition definition.

Gut microbiota is involved in the alleviation of loperamide-induced constipation by honey supplementation in mice

Constipation is one of the most common functional gastrointestinal disorders accompanied with intestinal dysbiosis. Laxatives for constipation usually have side effects. Bee honey is a natural food with unique composition, antimicrobial properties, and bifidogenic effect. In order to assess whether honey can ameliorate loperamide-induced constipation in BALB/c mice through the alteration of the gut microbiota, the present study was undertaken. Mice were given Jarrah honey (7.5 g/kg body weight) by gavage once per day for 5 days. Fecal water content, intestinal transit rate together with the colon concentrations of substance P (SP), vasoactive intestinal peptide (VIP), and serotonin (5-hydroxytryptamine; 5-HT) were evaluated. Furthermore, we determined the effect of honey treatment on gut microbiota in mice using stool genomic 16S rRNA sequencing. As a result, honey showed an obvious improvement in fecal water content and alleviated constipation by modulating the microbial composition of the microbiota, and this was highly associated with a proportional decrease in gut Desulfovibrio. In addition, we found that the colon level of neurotransmitters SP and VIP was significantly related to microbial variations. Our results indicate that gut microbiota is involved in the alleviation of loperamide-induced constipation by honey supplementation in mice, and it could be considered as an evaluating parameter in constipation therapy strategies.

CFTR is a negative regulator of γδ T cell IFN-γ production and antitumor immunity

CFTR, a chloride channel and ion channel regulator studied mostly in epithelial cells, has been reported to participate in immune regulation and likely affect the risk of cancer development. However, little is known about the effects of CFTR on the differentiation and function of γδ T cells. In this study, we observed that CFTR was functionally expressed on the cell surface of γδ T cells. Genetic deletion and pharmacological inhibition of CFTR both increased IFN-γ release by peripheral γδ T cells and potentiated the cytolytic activity of these cells against tumor cells both in vitro and in vivo. Interestingly, the molecular mechanisms underlying the regulation of γδ T cell IFN-γ production by CFTR were either TCR dependent or related to Ca²⁺ influx. CFTR was recruited to TCR immunological synapses and attenuated Lck-P38 MAPK-c-Jun signaling. In addition, CFTR was found to modulate TCR-induced Ca²⁺ influx and membrane potential (V_m)-induced Ca²⁺ influx and subsequently regulate the calcineurin-NFATc1 signaling pathway in γδ T cells. Thus, CFTR serves as a negative regulator of IFN-γ production in γδ T cells and the function of these cells in antitumor immunity. Our investigation suggests that modification of the CFTR activity of γδ T cells may be a potential immunotherapeutic strategy for cancer.

Validity and Reliability of a Novel Multimodal Questionnaire for the Assessment of Abdominal Symptoms in People with Cystic Fibrosis (CFAbd-Score)

BACKGROUND AND OBJECTIVE

For people with cystic fibrosis, validated patient-reported outcome measures for the assessment of the complex abdominal involvement are lacking. The objective of this study was to examine whether the CFAbd-Score, a novel questionnaire consisting of 28 items, meets the essential requirements (validity and reliability) for a patient-reported outcome measure according to US Food and Drug Administration recommendations.

METHODS

Content validity was assessed by recording the frequencies and severity of symptoms that occurred during the prior 2 weeks in patients with cystic fibrosis (n = 116; aged ≥ 6 years). Comparing the CFAbd-Score results obtained from patients with cystic fibrosis and healthy controls (n = 88), we determined known-groups validity. To explore the structure of the patient-reported outcome measure, a factor analysis was conducted. Internal consistency of the five extracted score domains was assessed using Cronbach's alpha. For test-retest reliability, a subgroup of patients (n = 43) was reevaluated and intra-class correlation coefficients were determined.

RESULTS

The CFAbd-Score differentiated patients with cystic fibrosis from healthy controls with a large effect size (17.3 ± 1.1 vs. 8.0 ± 0.7 points; p < 0.001; Cohen's d = 0.85). Items, domains, and scores reflected the relevance to patients with cystic fibrosis and allowed a differentiation between subgroups of patients with cystic fibrosis (e.g., patients with and without abdominal pain, pancreatic sufficiency, and age groups). High item-domain loadings as well as good to excellent internal consistency and reproducibility (Cronbach's α = 0.70-0.92; intra-class correlation coefficient = 0.932, 95% confidence interval 0.874-0.963) indicated construct validity and reliability.

CONCLUSIONS

The CFAbd-Score has successfully passed through key steps of the iterative process of patient-reported outcome measure development. Prospectively, the CFAbd-Score is proposed as a patient-centered instrument for monitoring abdominal symptoms and, most interestingly, for evaluating changes in symptoms with novel treatments such as cystic fibrosis transmembrane regulator modulators.

TRAIL REGISTRATION

ClinicalTrials.gov: NCT03052283.

Distal intestinal obstruction syndrome: an important differential diagnosis for abdominal pain in patients with cystic fibrosis

As life expectancy for those with cystic fibrosis (CF) now exceeds 40 years of age, adult hospitals away from specialized CF services are being exposed more frequently to people with acute complications of CF. Well-known manifestations of CF include pulmonary disease and pancreatic insufficiency with malabsorption. However, a less well-known entity is distal intestinal obstruction syndrome (DIOS), which is an important cause of obstructive symptoms in people with CF that must be differentiated from other causes of bowel obstruction. However, one confounding factor is that adults with CF may have elements of both DIOS and mechanical bowel obstruction due to adhesions from previous operations. A recent tragic outcome in a young adult with CF highlights the need for all doctors, both junior and senior, especially those who are not directly involved in day-to-day CF care, to understand the features of DIOS and the appropriate management, which differs from that of a mechanical bowel obstruction. This review aims to highlight the clinical and pathophysiological features of DIOS, differentiate it from other causes of bowel obstruction and contrast management strategies. Improved knowledge of DIOS will help to facilitate appropriate recognition and permit optimal, multidisciplinary management of this CF complication.

Case report of synchronous post-lung transplant colon cancers in the era of colorectal cancer screening recommendations in cystic fibrosis: screening "too early" before it's too late

BACKGROUND

The increasing life expectancy of individuals with Cystic Fibrosis (CF) is likely to be associated with new age-related challenges, colorectal cancer (CRC) most notably; recent consensus recommendations for CRC screening published in 2018 represent an important early step in addressing the emerging awareness of CF as a gastrointestinal cancer syndrome. These recommendations, however, need to be further refined based on more systematic data. We discuss an illustrative first-ever case of synchronous CRC arising in a post-lung transplant individual with CF within the recommended surveillance interval after a well-documented prior normal colonoscopy.

CASE PRESENTATION

A 51-year-old female individual with homozygous F508del CF, presents to clinic with abdominal discomfort and intermittent blood in stools. She had previously undergone bilateral lung transplantation 18 years earlier, as well as two kidney transplants related to immunosuppression-related nephrotoxicity. A diagnostic colonoscopy was performed which revealed the presence of two separate synchronous colon cancers in the cecum and transverse colon; she had undergone a colonoscopy three years prior to this exam which was structurally normal. Endoscopic quality indicators, including a good quality bowel preparation, colonoscopic withdrawal time > 12 min, and quarterly Adenoma Detection Rate (ADR) ranging from 50 to 70% for both male and female patients for the endoscopist from both colonoscopic exams, as well as secondary retrospective comparative review of the pertinent case images, diminish the risk for a "missed" cancer or advanced lesion on the index exam. These cancers did not demonstrate any immunohistochemical features suggestive of Lynch Syndrome, though the rapid progression to cancer within the surveillance interval (possibly non-polypoid in nature) is similar. This cancer presentation within the newly-established recommended colon cancer screening interval warrants concern.

CONCLUSIONS

This case prompts serious discussion regarding the length of surveillance intervals in the post-transplant CF population (a population at 20-30 times greater risk for CRC compared to the general non-CF population), as well as the importance of documenting endoscopic quality benchmarks, particularly if a narrative of interval CRC development continues to develop with further prospective monitoring and multi-center experience.

Acute and chronic non-pulmonary complications in adults with cystic fibrosis

INTRODUCTION

Cystic fibrosis (CF) is a genetic disease that primarily affects the respiratory system and often leads to respiratory failure and premature death. Although pulmonary complications contribute to 85% of deaths, non-pulmonary complications are responsible for significant morbidity and mortality in adults with CF. Areas covered: This review summarizes acute and chronic non-pulmonary complications in CF patients, with emphasis on emerging complications and in the context of the current growth and aging of the CF adult population. It also addresses the potential benefits of CF transmembrane conductance regulator modulator therapy. Complications that occur after solid organ (e.g. lung and/or liver) transplantation have been excluded. The review is based on an extensive search of the available literature, using PubMed and international guidelines, and on the authors' clinical experience. Expert commentary: Acute non-pulmonary complications have been well described but should be recognized and managed carefully. Managing chronic non-pulmonary complications is an important and changing aspect of CF patient care, particularly with the emergence of novel complications in adults. Early detection of non-pulmonary complications is essential to the development of prevention and treatment strategies that aim to further improve the survival and health status of adult CF patients.

Acute Appendicitis Masquerading Distal Intestinal Obstruction Syndrome in Adult Cystic Fibrosis

Overshadowed by Sino-pulmonary infections, Cystic Fibrosis (CF) commonly affects gastrointestinal organs because of secretory and motility dysfunction. Infrequently, these changes result in Distal Intestinal Obstruction Syndrome (DIOS), an increasingly diagnosed gastrointestinal entity in adult Cystic Fibrosis patients. We present a case 22-year-old male who presented to our hospital with right lower quadrant abdominal pain with suspicion of acute appendicitis and was subsequently diagnosed as DIOS. Our case highlights the importance of DIOS as one of the differential diagnosis of right lower quadrant abdominal pain in a patient with a CF, especially for physicians working at community hospitals which may not have a Cystic Fibrosis care program available.

Consuming Genistein Improves Survival Rates in the Absence of Laxative in ΔF508-CF Female Mice

Genistein is a naturally occurring isoflavone found in soy. Genistein has been shown to increase the open probability of the most common cystic fibrosis (CF) disease-associated mutation, ∆F508-CFTR. Mice homozygous for the ∆F508 mutation are characterized with severe intestinal disease and require constant laxative treatment for survival. This pathology mimics the intestinal obstruction (meconium ileus) seen in some cystic fibrosis patients. This study tested whether dietary supplementation with genistein would reduce the dependence of the ∆F508 CF mouse model on laxatives for survival, thereby improving mortality rates. At weaning (21 days), homozygous ∆F508 mice were maintained on one of three diet regimens for a period of up to 65 days: normal diet, normal diet plus colyte, or genistein diet. Survival rates for males were as follows: standard diet (38%, n = 21), standard diet plus colyte (83%, n = 42) and genistein diet (60%, n = 15). Survival rates for females were as follows: standard diet (47%, n = 19), standard diet plus colyte (71%, n = 38), and genistein diet (87%, n = 15). Average weight of male mice fed genistein diet increased by ~2.5 g more (p = 0.006) compared to those with colyte treatment. Genistein diet did not change final body weight of females. Expression of intestinal SGLT-1 increased 2-fold (p = 0.0005) with genistein diet in females (no change in males, p = 0.722). Expression of GLUT2 and GLUT5 was comparable between all diet groups. Genistein diet reduced the number of goblet cells per micrometer of crypt depth in female (p = 0.0483), yet was without effect in males (p = 0.7267). The results from this study demonstrate that supplementation of diet with genistein for ~45 days increases the survival rate of female ∆F508-CF mice (precluding the requirement for laxatives), and genistein only improves weight gain in males.

[Acute pulmonary and non-pulmonary complications in adults with cystic fibrosis]

INTRODUCTION

Cystic fibrosis (CF) is a genetic disease primarily affecting the lungs, which could lead to chronic respiratory failure and premature death. CF patients are usually followed in specialized centers, but may present outside of these centers when they seek care for acute pulmonary and/or non-pulmonary complications. The aim of this paper is to provide appropriate knowledge necessary for managing respiratory and non-respiratory emergencies in CF adults.

METHODS

The review is based on international guidelines, extensive search of the available literature using Pubmed, and experience of the CF reference center at Cochin hospital (Paris, France). Complications occurring after solid organ transplantation (e.g., lung and/or liver) are excluded from this review.

RESULTS

Main acute respiratory complications are pulmonary exacerbations, hemoptysis, pneumothorax and allergic bronchopulmonary aspergillosis. Acute non-respiratory complications include hyponatremic dehydration, acute pancreatitis, acute complications of gallstones, distal intestinal obstruction syndrome, symptomatic nephrolithiasis, acute kidney injury, drug intolerances and catheter-related acute complications.

CONCLUSION

This review summarizes acute pulmonary and non-pulmonary complications occurring in adults with CF, focusing on diagnosis and principles of treatment, with the aim of providing a reference that can be used in clinical practice.

Approach to chronic abdominal pain in Cystic Fibrosis

Abdominal pain in individuals with CF is challenging for the patient as well as the physician, as the differential diagnosis can be complex. Most gastrointestinal manifestations of CF present with regional abdominal pain. Pain localization, which requires knowledge of gut development and innervation, is crucial to understanding the pathophysiology of abdominal pain in CF. The location of the pain, together with the clinical presentation, shapes the differential diagnosis and thus guides the evaluation and management.

Unmet needs in cystic fibrosis: the next steps in improving outcomes

INTRODUCTION

Cystic fibrosis (CF) outcomes and survival have improved over the last century primarily due to advancements in antibiotics, nutritional, and pulmonary therapies. Reviewed here are the significant unmet needs that exist for individuals with CF. Areas covered: With the recent development of medications that address the underlying defect in the CF protein, there is hope that there will be continued improvement in CF outcomes. However, there remains a need to prevent or stop progression of CF-related complications, as the CF protein is important to several body systems. As end stage lung disease is the primary cause of mortality in CF, a need exists for advancements in pulmonary therapies to reduce time burden, identification of best practices for the treatment of pulmonary exacerbations, further development of anti-infective and anti-inflammatory therapies, and appropriately timed referral for lung transplantation at end-stage lung disease. Extra-pulmonary complications are increasingly recognized and better understanding of such problems as CF related liver disease is needed. Expert commentary: While CFTR modulators are available for the majority of CF patients, there remains a need for effective therapies to address infection, inflammation, irreversible lung disease, and extrapulmonary complications of CF.