The gallbladder and biliary tract in cystic fibrosis

Towards a Standardized Classification of the Hepatobiliary Manifestations in Cystic Fibrosis (CFHBI): A Joint ESPGHAN/NASPGHAN Position Paper

The broad spectrum of hepatobiliary involvement in cystic fibrosis (CF) has been commonly referred to as cystic fibrosis liver disease (CFLD). However, differences in the definitions of CFLD have led to variations in reported prevalence, incidence rates, and standardized recommendations for diagnosis and therapies. Harmonizing the description of the spectrum of hepatobiliary involvement in all people with CF (pwCF) is deemed essential for providing a reliable account of the natural history, which in turn supports the development of meaningful clinical outcomes in patient care and research. Recognizing this necessity, The European Society for Paediatric Gastroenterology Hepatology and Nutrition (ESPGHAN) and the North American Society for Pediatric Gastroenterology, Hepatology and Nutrition (NASPGHAN) commissioned and tasked a committee to develop and propose a systematic classification of the CF hepatobiliary manifestations to increase uniformity, accuracy, and comparability for clinical, registry, and research purposes. This report describes the committee's combined expert position statement on hepatobiliary involvement in CF, which has been endorsed by NASPGHAN and ESPGHAN. We recommend using CFHBI (Cystic Fibrosis Hepato-Biliary Involvement) as the updated term to describe and classify all hepatobiliary manifestations in all pwCF. CFHBI encompasses the current extensive spectrum of phenotypical, clinical, or diagnostic expressions of liver involvement observed in pwCF. We present a schematic categorization of CFHBI, which may also be used to track and classify the changes and development of CFHBI in pwCF over time. The proposed classification for CFHBI is based on expert consensus and has not been validated for clinical practice and research purposes. Achieving validation should be an important aim for future research.

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.

Cystic fibrosis-related liver disease: Clinical presentations, diagnostic and monitoring approaches in the era of CFTR modulator therapies

Cystic fibrosis (CF) is the most common autosomal recessive disease in the Caucasian population. Cystic fibrosis-related liver disease (CFLD) is defined as the pathogenesis related to the underlying CFTR defect in biliary epithelial cells. CFLD needs to be distinguished from other liver manifestations that may not have any pathological significance. The clinical/histological presentation and severity of CFLD vary. The main histological presentation of CFLD is focal biliary fibrosis, which is usually asymptomatic. Portal hypertension develops in a minority of cases (about 10%) and may require specific management including liver transplantation for end-stage liver disease. Portal hypertension is usually the result of the progression of focal biliary fibrosis to multilobular cirrhosis during childhood. Nevertheless, non-cirrhotic portal hypertension as a result of porto-sinusoidal vascular disease is now identified increasingly more frequently, mainly in young adults. To evaluate the effect of new CFTR modulator therapies on the liver, the spectrum of hepatobiliary involvement must first be precisely classified. This paper discusses the phenotypic features of CFLD, its underlying physiopathology and relevant diagnostic and follow-up approaches, with a special focus on imaging.

Micro-gallbladder: A rare surgical problem

Micro-gallbladder is a rare clinical entity and mostly linked with cystic fibrosis (CF), which is an autosomal recessive disease involving a protein Cystic fibrosis transmembrane conductance regulator (CFTR) which regulates secretion and absorption in the pulmonary, reproductive and gastrointestinal systems including the liver. Biliary secretion becomes hyperviscous, leading to cholestasis and partial obstruction of the cystic duct. This causes recurrent cholecystitis and gallstone formation. Ultimately, atrophy of the gallbladder results, thus a 'micro-gallbladder' defined as being <2-3 cm in length and 0.5-1.5 cm in width. A shrunken gallbladder from recurrent attacks of gallstone-induced cholecystitis is not typically termed as a micro-gallbladder. Laparoscopic cholecystectomy is definitive treatment for symptomatic micro-gallbladder, even though most cases are managed conservatively without surgery. We report a case of symptomatic micro-gallbladder in a non-CF patient, managed successfully by laparoscopic cholecystectomy.

Early pathogenesis of cystic fibrosis gallbladder disease in a porcine model

Hepatobiliary disease causes significant morbidity in people with cystic fibrosis (CF), yet this problem remains understudied. We previously found that newborn CF pigs have microgallbladders with significant luminal obstruction in the absence of infection and consistent inflammation. In this study, we sought to better understand the early pathogenesis of CF pig gallbladder disease. We hypothesized that loss of CFTR would impair gallbladder epithelium anion/liquid secretion and increase mucin production. CFTR was expressed apically in non-CF pig gallbladder epithelium but was absent in CF. CF pig gallbladders lacked cAMP-stimulated anion transport. Using a novel gallbladder epithelial organoid model, we found that Cl- or HCO3- was sufficient for non-CF organoid swelling. This response was absent for non-CF organoids in Cl-/HCO3--free conditions and in CF. Single-cell RNA-sequencing revealed a single epithelial cell type in non-CF gallbladders that coexpressed CFTR, MUC5AC, and MUC5B. Despite CF gallbladders having increased luminal MUC5AC and MUC5B accumulation, there was no significant difference in the epithelial expression of gel-forming mucins between non-CF and CF pig gallbladders. In conclusion, these data suggest that loss of CFTR-mediated anion transport and fluid secretion contribute to microgallbladder development and luminal mucus accumulation in CF.

Biliary disease and cholecystectomy after initiation of elexacaftor/ivacaftor/tezacaftor in adults with cystic fibrosis

Individuals with cystic fibrosis (CF) have an increased risk for gallbladder abnormalities and biliary tract disease, but the reported incidence of these manifestations of CF varies widely in the literature. With the approval of elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA), increasing numbers of CF patients have been initiated on highly effective cystic fibrosis transmembrane regulator (CFTR) modulator therapy. While elevations in hepatic panel are known potential side effects of CFTR modulators, there have been no published cases of biliary disease or acute cholecystitis attributed to these medications. In this case series, we describe seven patients at two adult CF centers with biliary colic shortly after initiation with ELX/TEZ/IVA, six of whom required cholecystectomy.

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 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.

The Efficacy of MRI in the diagnostic workup of cystic fibrosis-associated liver disease: A clinical observational cohort study

PURPOSE

To identify independent imaging features and establish a diagnostic algorithm for diagnosis of cystic fibrosis (CF)-associated liver disease (CFLD) in CF patients compared to controls using gadoxetic acid-enhanced MRI.

METHODS

A total of 90 adult patients were enrolled: 50 with CF, 40 controls. The CF group was composed of two subgroups: a retrospective test subgroup (n = 33) and a prospective validation subgroup (n = 17). Controls (patients with normal liver enzymes and only benign focal liver lesions) were divided accordingly (27:13). MRI variables, including quantitative and qualitative parameters, were used to distinguish CFLD from controls using clinical symptoms, laboratory tests and Debray criteria. Disease severity was classified according to Child-Pugh and Albumin-Bilirubin (ALBI) scores. Fifteen qualitative single-lesion CF descriptors were defined. Two readers independently evaluated the images. Univariate statistical analysis was performed to obtain significant imaging features that differentiate CF patients from controls. Through multivariate analysis using chi-squared automatic interaction detector (CHAID) methodology the most important descriptors were identified. Diagnostic performance was assessed by receiver-operating characteristic (ROC) analysis.

RESULTS

Three independent imaging descriptors distinguished CFLD from controls: (1) presence of altered gallbladder morphology; (2) periportal tracking; and (3) periportal fat deposition. Prospective validation of the classification algorithm demonstrated a sensitivity of 94.1% and specificity of 84.6% for discriminating CFLD from controls. Disease severity was well associated with the imaging features.

CONCLUSIONS

A short unenhanced MRI protocol can identify the three cardinal imaging features of CFLD. The hepatobiliary phase of gadoxetic acid-enhanced MRI can define CFLD progression.

KEY POINTS

• Using a multivariate classification analysis, we identified three independent imaging features, altered gallbladder morphology (GBAM), periportal tracking (PPT) and periportal fat deposition (PPFD), that could diagnose CFLD with high sensitivity, 94.1 % (95% CI: 71.3-99.9) and moderate specificity, 84.6 % (95% CI: 54.6-98.1). • Based upon the results of this study, gadoxetic acid-enhanced MRI with DWI is able to diagnose early-stage CFLD, as well as its progression.

Gallbladder and bile duct disease in Cystic Fibrosis

Cystic fibrosis (CF) is a multi-organ, clinically diverse disorder caused by mutations in the cystic fibrosis transmembrane conductance receptor (CFTR). Awareness of extra-pulmonary manifestations, including gastrointestinal and hepatobiliary disturbances, is an increasingly important part of providing high-quality care to patients with CF. Furthermore, biliary disorders, including gallbladder and bile duct disease, are common complications of CF. Therefore, a thorough understanding and efficient clinical evaluation of the gallbladder and biliary tree is an important aspect of integrated care for the patient with CF in order to prevent progression of undetected pathology. This best practice article summarizes the basis for gallbladder and bile duct pathology, describes the context and clinical presentation of biliary disease, and provides recommended approaches to delivery of high-quality care for patients with CF.

Biliary manifestations of systemic diseases

Patients with a variety of systemic diseases may present with clinical indications of biliary tract disorders. This article describes a group of systemic conditions associated with bile duct abnormalities and the role of endoscopic therapy in their diagnosis and management.

Molecular mechanisms of ursodeoxycholic acid toxicity & side effects: ursodeoxycholic acid freezes regeneration & induces hibernation mode

Ursodeoxycholic acid (UDCA) is a steroid bile acid approved for primary biliary cirrhosis (PBC). UDCA is reported to have “hepato-protective properties”. Yet, UDCA has “unanticipated” toxicity, pronounced by more than double number of deaths, and eligibility for liver transplantation compared to the control group in 28 mg/kg/day in primary sclerosing cholangitis, necessitating trial halt in North America. UDCA is associated with increase in hepatocellular carcinoma in PBC especially when it fails to achieve biochemical response (10 and 15 years incidence of 9% and 20% respectively). “Unanticipated” UDCA toxicity includes hepatitis, pruritus, cholangitis, ascites, vanishing bile duct syndrome, liver cell failure, death, severe watery diarrhea, pneumonia, dysuria, immune-suppression, mutagenic effects and withdrawal syndrome upon sudden halt. UDCA inhibits DNA repair, co-enzyme A, cyclic AMP, p53, phagocytosis, and inhibits induction of nitric oxide synthatase. It is genotoxic, exerts aneugenic activity, and arrests apoptosis even after cellular phosphatidylserine externalization. UDCA toxicity is related to its interference with drug detoxification, being hydrophilic and anti-apoptotic, has a long half-life, has transcriptional mutational abilities, down-regulates cellular functions, has a very narrow difference between the recommended (13 mg/kg/day) and toxic dose (28 mg/kg/day), and it typically transforms into lithocholic acid that induces DNA strand breakage, it is uniquely co-mutagenic, and promotes cell transformation. UDCA beyond PBC is unjustified.

Intensive care management of the patient with cystic fibrosis

Cystic fibrosis was previously thought to be a disease of childhood. With a better understanding of this condition along with improvements in therapy, patients with cystic fibrosis are now living well into adulthood. The aim of this article is to familiarize the intensive care unit physician with cystic fibrosis care, to discuss complications associated with cystic fibrosis specifically related to the intensive care unit, and to detail the current recommendations for the clinical management of the patient with cystic fibrosis. With advancing disease, the most severely affected organs are the lungs. Obstruction, infection, and inflammation contribute to the decline of pulmonary function, ultimately leading to death. Some patients may be eligible for lung transplantation, but choosing wisely will affect posttransplant survival. Because other organs are affected by the genetic defect and associated treatments, serious complications related to the liver, pancreas, intestines, and kidneys must be considered by the intensivist faced with a patient with cystic fibrosis. As practitioners, the fact that not all patients will survive and help our patients and families gracefully through the end-of-life process should be accepted.

Heterogeneity of the intrahepatic biliary epithelium

The objectives of this review are to outline the recent findings related to the morphological heterogeneity of the biliary epithelium and the heterogeneous pathophysiological responses of different sized bile ducts to liver gastrointestinal hormones and peptides and liver injury/toxins with changes in apoptotic, proliferative and secretory activities. The knowledge of biliary function is rapidly increasing because of the recognition that biliary epithelial cells (cholangiocytes) are the targets of human cholangiopathies, which are characterized by proliferation/damage of bile ducts within a small range of sizes. The unique anatomy, morphology, innervation and vascularization of the biliary epithelium are consistent with function of cholangiocytes within different regions of the biliary tree. The in vivo models [e.g., bile duct ligation (BDL), partial hepatectomy, feeding of bile acids, carbon tetrachloride (CCl₄) or α-naphthylisothiocyanate (ANIT)] and the in vivo experimental tools [e.g., freshly isolated small and large cholangiocytes or intrahepatic bile duct units (IBDU) and primary cultures of small and large murine cholangiocytes] have allowed us to demonstrate the morphological and functional heterogeneity of the intrahepatic biliary epithelium. These models demonstrated the differential secretory activities and the heterogeneous apoptotic and proliferative responses of different sized ducts. Similar to animal models of cholangiocyte proliferation/injury restricted to specific sized ducts, in human liver diseases bile duct damage predominates specific sized bile ducts. Future studies related to the functional heterogeneity of the intrahepatic biliary epithelium may disclose new pathophysiological treatments for patients with cholangiopathies.

Whatever happened to "neonatal hepatitis"?

'Idiopathic neonatal hepatitis' is a term that has traditionally been used to denote a clinical syndrome manifest by prolonged jaundice in the neonate. This description is now used much less frequently because recent studies unite well-defined clinical, biochemical and molecular features of intrahepatic cholestasis into specific syndromes. Advances in the understanding of the molecular basis of cholestatic syndromes now enable the classification of syndromes based on biology and offer an opportunity to develop new diagnostic approaches and treatment strategies that take into account the genetic make-up of the child with cholestasis.