Cholestatic liver disease in children

Primary Cilia, Hypoxia, and Liver Dysfunction: A New Perspective on Biliary Atresia

Ciliopathies are disorders that affect primary or secondary cellular cilia or structures associated with ciliary function. Primary cilia (PC) are essential for metabolic regulation and embryonic development, and pathogenic variants in cilia-related genes are linked to several pediatric conditions, including renal-hepatic diseases and congenital defects. Biliary atresia (BA) is a progressive infantile cholangiopathy and the leading cause of pediatric liver transplantation. Although the exact etiology of BA remains unclear, evidence suggests a multifactorial pathogenesis influenced by both genetic and environmental factors. Patients with BA and laterality defects exhibit genetic variants associated with ciliopathies. Interestingly, even isolated BA without extrahepatic anomalies presents morphological and functional ciliary abnormalities, suggesting that environmental triggers may disrupt the ciliary function. Among these factors, hypoxia has emerged as a potential modulator of this dysfunction. Hypoxia-inducible factor 1-alpha (HIF-1α) plays a central role in hepatic responses to oxygen deprivation, influencing bile duct remodeling and fibrosis, which are key processes in BA progression. This review explores the crosstalk between hypoxia and hepatic ciliopathies, with a focus on BA. It discusses the molecular mechanisms through which hypoxia may drive disease progression and examines the therapeutic potential of targeting hypoxia-related pathways. Understanding how oxygen deprivation influences ciliary function may open new avenues for treating biliary ciliopathies and improving patient outcomes.

Timing and Indications for Liver Transplantation for Children with Chronic Liver Disease

Chronic liver disease (CLD) in children poses significant challenges, necessitating timely management to mitigate morbidity and mortality. Liver transplantation (LT) has emerged as a transformative intervention, offering improved long-term survival for paediatric patients with CLD. This review explores the evolving landscape of liver transplantation, focusing on indications and timing considerations. The aetiology of CLD is diverse, encompassing intrahepatic, extrahepatic cholestatic conditions, metabolic diseases, malignancy, and drug-induced liver injury. LT is indicated when children exhibit signs of hepatic decompensation, necessitating a comprehensive evaluation to assess transplant suitability. Indications for LT include biliary atresia, inborn errors of metabolism, hepatocellular carcinoma, and emerging indications such as mitochondrial hepatopathies and acute on chronic liver failure. The timing of transplantation is critical, emphasizing the need for early recognition of decompensation signs to optimise outcomes. Advancements in LT techniques and immunosuppressive therapies have enhanced patient and graft survival rates. Various transplant modalities, including reduced-size LT and living-related LT, offer tailored solutions to address the unique needs of paediatric patients. While LT represents a cornerstone in the management of paediatric CLD, careful patient selection, multidisciplinary collaboration, and ongoing refinements in transplant protocols are imperative for optimizing outcomes and addressing the evolving landscape of paediatric liver disease management.

Structural Disruption of Cilia and Increased Cytoplasmic Tubulin in Biliary Atresia-An Exploratory Study Focusing on Early Postoperative Prognosis Following Portoenterostomy

Introduction: Biliary atresia (BA) is a progressive hepatobiliary disease in infants, leading to liver failure and the need for transplantation. While its etiopathogenesis remains unclear, recent studies suggest primary cilia (PC) disruption plays a role. This study investigates correlations between PC and cytoplasmic tubulin (TUBA4A) alterations with hypoxia in patients with the isolated form of BA, focusing on native liver survival. Methods: Using qualitative and quantitative digital image analysis of immunofluorescence-stained liver samples, we assessed PC and TUBA4A features correlating these findings with HIF-1α nuclear positivity, clinical-laboratory data, and early native liver survival. Liver samples from fourteen BA patients and six controls with another liver disease were analyzed by digital image analysis, with data evaluated using Spearman's correlation and independent t-tests. Results: HIF-1α positivity in cholangiocytes was observed in 42.8% of BA patients. While the PC ratio per biliary structure (cilia ratio status, CRs) was similar between BA patients and controls, PC length was decreased in BA patients. Cytoplasmic TUBA4A levels were elevated in BA patients. CRs positively correlated with lower cytoplasmic TUBA4A expression and was higher in patients without HIF-1α nuclear positivity. Reduced cilia length correlated with higher bilirubin levels at portoenterostomy. Predictors of early poor prognosis (death or need for transplantation until 1 year of life) included HIF-1α positivity, elevated direct bilirubin levels, decreased cilia length, PC bending, and increased TUBA4A expression. Conclusions: Reduced PC length, PC bending, and increased intensity of cytoplasmic TUBA4A expression occur in the isolated BA clinical type and negatively impact the early prognosis after post-portoenterostomy. These findings suggest the existence of a disruption in the tubulin transport between cytoplasm and PC. The detrimental effect of HIF-1alpha pathway activation over early native liver survival was confirmed, although independently from PC or cytoplasmic tubulin features.

Pediatric Perspectives on Liver Cirrhosis: Unravelling Clinical Patterns and Therapeutic Challenges

Background: Liver cirrhosis presents significant challenges in the pediatric population due to a complex interplay of etiological factors, clinical manifestations, and limited therapeutic options. The leading contributors to cirrhosis among pediatric patients are chronic cholestasis, metabolic disorders present from birth, and long-term hepatitis. Materials and method: Our narrative review aimed to synthesize literature data on the etiology, clinical picture, diagnostic techniques, optimal management of complications, and timely transplantation. Results: The epidemiology of liver cirrhosis in pediatric patients is evolving. The introduction of a universal vaccination and effective long-term viral suppression in viral hepatitis have significantly decreased complications rates. Liver transplantation programs worldwide have also improved the management of cirrhosis complications. Conclusions: Early diagnosis, comprehensive management strategies, and advancements in treatment modalities are critical for improving outcomes. Understanding these differences is crucial in providing age-appropriate care and support for those affected by cirrhosis.

The Pharmacological Properties of Red Grape Polyphenol Resveratrol: Clinical Trials and Obstacles in Drug Development

Resveratrol is a stilbenoid from red grapes that possesses a strong antioxidant activity. Resveratrol has been shown to have anticancer activity, making it a promising drug for the treatment and prevention of numerous cancers. Several in vitro and in vivo investigations have validated resveratrol's anticancer capabilities, demonstrating its ability to block all steps of carcinogenesis (such as initiation, promotion, and progression). Additionally, resveratrol has been found to have auxiliary pharmacological effects such as anti-inflammatory, cardioprotective, and neuroprotective activity. Despite its pharmacological properties, several obstacles, such as resveratrol's poor solubility and bioavailability, as well as its adverse effects, continue to be key obstacles to drug development. This review critically evaluates the clinical trials to date and aims to develop a framework to develop resveratrol into a clinically viable drug.

Protocols of Investigation of Neonatal Cholestasis-A Critical Appraisal

Neonatal cholestasis (NC) starts during the first three months of life and comprises extrahepatic and intrahepatic groups of diseases, some of which have high morbimortality rates if not timely identified and treated. Prolonged jaundice, clay-colored or acholic stools, and choluria in an infant indicate the urgent need to investigate the presence of NC, and thenceforth the differential diagnosis of extra- and intrahepatic causes of NC. The differential diagnosis of NC is a laborious process demanding the accurate exclusion of a wide range of diseases, through the skillful use and interpretation of several diagnostic tests. A wise integration of clinical-laboratory, histopathological, molecular, and genetic evaluations is imperative, employing extensive knowledge about each evaluated disease as well as the pitfalls of each diagnostic test. Here, we review the difficulties involved in correctly diagnosing the cause of cholestasis in an affected infant.

Combined effect of hydrogen sulfide and mesenchymal stem cells on mitigating liver fibrosis induced by bile duct ligation: Role of anti-inflammatory, anti-oxidant, anti-apoptotic, and anti-fibrotic biomarkers

OBJECTIVES

Liver fibrosis eventually develops into cirrhosis and hepatic failure, which can only be treated with liver transplantation. We aimed to assess the potential role of hydrogen sulfide (H₂S) alone and combined with bone marrow-derived mesenchymal stem cells (BM-MSCs) on hepatic fibrosis induced by bile-duct ligation (BDL) and to compare their effects to silymarin.

MATERIALS AND METHODS

Alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TB), and alkaline phosphatase (ALP) were investigated in serum. Gene expression levels of CBS (cystathionine β-synthase), CSE (cystathionine γ-lyase), and alpha-smooth muscle actin (α- SMA) were measured in liver tissues using RT-PCR. Hepatic protein kinase (Akt) was assessed by Western blot assay. Liver oxidative stress markers, malondialdehyde (MDA), and reduced glutathione (GSH) were analyzed by the colorimetric method. Lipocalin-2 (LCN2) and transforming growth factor-β (TGF-β) were measured using ELIZA. Liver tissues were examined by H&E and Masson trichome staining for detection of liver necrosis or fibrosis. Caspase 3 expression was evaluated by immunohistochemistry.

RESULTS

H₂S and BM-MSCs ameliorated liver function and inhibited inflammation and oxidative stress detected by significantly decreased serum ALT, AST, ALP, TB, and hepatic MDA, Akt, TGF-β, LCN2, and α-SMA expression and significantly increased CBS and CSE gene expression levels. They attenuated hepatic apoptosis evidenced by decreased hepatic caspase expression.

CONCLUSION

Combined treatment with H₂S and BM-MSCs could attenuate liver fibrosis induced by BDL through mechanisms such as anti-inflammation, anti-oxidation, anti-apoptosis, anti-fibrosis, and regenerative properties indicating that using H₂S and MSCs may represent a promising approach for management of cholestatic liver fibrosis.

Increased Water-Solubility and Maintained Antioxidant Power of Resveratrol by Its Encapsulation in Vitamin E TPGS Micelles: A Potential Nutritional Supplement for Chronic Liver Disease

Children affected by chronic liver disease exhibit impaired neurocognitive development and growth due to the low absorption and digestion of nutrients. Furthermore, malnutrition is an adverse prognostic factor in liver transplantation as it is associated with an increase in morbidity and mortality. D-α-tocopheryl-polyethylene-glycol-succinate (TPGS) is currently administered per os as a vitamin E source to improve children's survival and well-being; however, TPGS alone does not reverse spinocerebellar degeneration and lipid peroxidation. To potentiate the effects of TPGS, we loaded micelles with resveratrol (RES), a natural polyphenol, with antioxidant and antiinflammatory activities, which has demonstrated protective action in the liver. Firstly, we investigated the suitability of TPGS to encapsulate RES in micelles by means of a phase-solubility study, then RES-TPGS formulations were prepared via solvent casting and solvent diffusion evaporation methods. RES-TPGS colloidal dispersions showed small mean diameters (12 nm), low polydispersity, and quite neutral Zeta potentials. The formulations showed a sustained drug release and a good drug loading capacity, further confirmed by infrared spectroscopy and differential scanning calorimetry. RES-TPGSs exhibited unaltered antioxidant activity compared to pristine RES via the DPPH assay and a significant reduction in toxicity compared to empty TPGS on HaCaT cells. Thus, RES-TPGS micelles may overcome the challenges of current liver disease therapy by providing more protective effects thanks to the antioxidant activity of RES and by reducing the surfactant toxicity on normal cells.

Bile Acids Impair Vaccine Response in Children With Biliary Atresia

Background

Vaccination is the best way to protect children under 5 years from death or disability. Children with biliary atresia (BA), which is the most common pediatric cholestatic end-stage liver disease (PELD), are more vulnerable to infectious diseases. However, the vaccination coverage and factors modulating vaccine responses in children with BA are largely unknown.

Methods

In this study, 288 children (median age: 7 months) diagnosed with BA before liver transplantation were enrolled for the evaluation of vaccination status and the factors affecting the immune response to the hepatitis B (HBV) vaccine. Moreover, 49 BA children (median age: 4 months) were enrolled for flow cytometric analysis of CD4⁺ T cells and CD19⁺ B cell subsets and correlations with serum bile acid levels.

Results

Generally, these children had very low routine vaccination rates for the meningococcal serogroup AC (Men AC) (41.2%), measles-mumps-rubella (MMR) (31.3%), poliomyelitis (Polio) (25.3%), hepatitis A (HAV) (25.0%), Japanese encephalitis (JE) (15.0%), diphtheria-tetanus-pertussis (DTP) (14.2%), meningococcal serogroup A (Men A) (13.5%) and varicella (VAR) (10.8%) vaccines, but not for the HBV (96.2%) and bacillus Calmette-Guérin (BCG) (84.7%) vaccines. Remarkably, 19.8% (57/288) of the patients had HBV infection. Out of 220 patients vaccinated for HBV, 113 (51.4%), 85 (38.6%) and 22 (10%) had one, two or three doses of the HBV vaccine, respectively. Furthermore, logistic regression analysis revealed that the bile acid level was an independent factor associated with poor HBV vaccine response (p = 0.03; OR = 0.394; 95% CI = 0.170-0.969). Immunophenotyping showed that bile acids were only negatively correlated with the CD19⁺CD27⁺IgG⁺ post-class-switched memory B cell ratio (p = 0.01).

Conclusion

This study reveals the overall vaccination rates of routine vaccines in Chinese BA children are very low and the poor HBV vaccine responses are associated with bile acids, possibly via the inhibition of CD19⁺CD27⁺IgG⁺ post-class-switched memory B cell response.

Clinical Trial Registration

http://www.chictr.org.cn, identifier ChiCTR1800019165.

Etiology of cirrhosis in the young

The etiology and incidence of cirrhosis in adults has been well studied, however there is scant data in younger patients. The aim of this study was to determine causes of cirrhosis in patients ≤40 years old. In this multi-institutional retrospective study, pathology databases were searched for patients ≤40-year-old with a diagnosis of cirrhosis from 1995 to 2018. Clinical charts and pathology reports were reviewed to identify etiologies of cirrhosis in each case. The patients were divided into 4 age groups (<1, 1- < 5, 5- < 18, and 18-40 years old) for further analysis. We identified 594 patients (264 female, 330 male). Among <18-year-old patients, congenital cholestatic diseases and developmental disorders were the most common causes of cirrhosis (50.2%, 172/342). Metabolic and genetic diseases were also seen more commonly in this age group (16.6%, 57/342). In contrast, viral hepatitides were the most common cause of cirrhosis in 18-40-year-old patients (39.6%, 100/252) followed by autoimmune and fatty liver disease (22.2%, 56/252 and 15.07%, 38/252, respectively). Cryptogenic cirrhosis (overall 7.2%, 42/594) was seen in 3% (4/133), 1.4% (1/69), 10.7% (15/140) and 8.7% (22/252) of patients aged <1, 1- < 5, 5- < 18, and 18-40 years, respectively. Developmental and metabolic disorders are the most common causes of cirrhosis in children (<18), while viral hepatitides are leading causes in adolescents and young adults (18-40) similar to adults. The incidence of cryptogenic cirrhosis also varies depending on the age, being lowest in 1- < 5 year and highest in 5- < 18 year age group children.

Panel-Based Next-Generation Sequencing for the Diagnosis of Cholestatic Genetic Liver Diseases: Clinical Utility and Challenges

OBJECTIVE

To test the application of a target enrichment next-generation sequencing (NGS) jaundice panel in genetic diagnosis of pediatric liver diseases.

STUDY DESIGN

We developed a capture-based target enrichment NGS jaundice panel containing 42 known disease-causing genes associated with jaundice or cholestasis and 10 pathway-related genes. During 2015-2017, 102 pediatric patients with various forms of cholestasis or idiopathic liver diseases were tested, including patients with initial diagnosis of cholestasis in infancy, progressive familial intrahepatic cholestasis, syndromic cholestasis, Wilson disease, and others.

RESULTS

Of the 102 patients, 137 mutations/variants in 44 different genes were identified in 84 patients. The genetic disease diagnosis rate was 33 of 102 (32.4%). A total of 79 of 102 (77.5%) of patients had at least 1 heterozygous genetic variation. Those with progressive intrahepatic cholestasis or syndromic cholestasis in infancy had a diagnostic rate of 62.5%. Disease-causing mutations, including ATP8B1, ABCB11, ABCB4, ABCC2, TJP2, NR1H4 (FXR), JAG1, AKR1D1, CYP7B1, PKHD1, ATP7B, and SLC25A13, were identified. Nine patients had unpredicted genetic diagnosis with atypical phenotype or novel mutations in the investigational genes. We propose an NGS diagnosis classification categorizing patients into high (n = 24), moderate (n = 9), or weak (n = 25) levels of genotype-phenotype correlations to facilitate patient management.

CONCLUSIONS

This panel enabled high-throughput detection of genetic variants and disease diagnosis in patients with a long list of candidate causative genes. A NGS report with diagnosis classification may aid clinicians in data interpretation and patient management.

Advances in diagnosis of chronic liver diseases in pediatric patients

BACKGROUND

Chronic liver diseases (CLD) present important clinical problem in children with various age-dependent causes. Nonalcoholic fatty liver disease (NAFLD) with its increasing prevalence is a major problem with regard to its timely recognition and the need for long-term disease monitoring. At present, a perfect non-invasive method for the evaluation of liver fibrosis is not available.

METHODS

A non-systematic literature search was performed to summarize the current knowledge about transient elastography (TE) with controlled attenuation parameter (CAP) in children with CLD. Ovid MEDLINE, Ovid EMBASE, Google scholar, and The Cochrane Library databases were searched for relevant articles evaluating TE in the pediatric population.

RESULTS

Normal values of liver stiffness measurements (LSM) according to the age are given, as well as the advantages and disadvantages of the method. The utility of TE in specific liver disease in pediatric population is summarized.

CONCLUSIONS

TE with CAP is a valuable non-invasive method for the liver-damage assessment. Clinical interpretation of TE results should be made in parallel with the assessment of the patient's demographics, disease etiology, and essential laboratory parameters.

Jaundice revisited: recent advances in the diagnosis and treatment of inherited cholestatic liver diseases

Background

Jaundice is a common symptom of inherited or acquired liver diseases or a manifestation of diseases involving red blood cell metabolism. Recent progress has elucidated the molecular mechanisms of bile metabolism, hepatocellular transport, bile ductular development, intestinal bile salt reabsorption, and the regulation of bile acids homeostasis.

Main body

The major genetic diseases causing jaundice involve disturbances of bile flow. The insufficiency of bile salts in the intestines leads to fat malabsorption and fat-soluble vitamin deficiencies. Accumulation of excessive bile acids and aberrant metabolites results in hepatocellular injury and biliary cirrhosis. Progressive familial intrahepatic cholestasis (PFIC) is the prototype of genetic liver diseases manifesting jaundice in early childhood, progressive liver fibrosis/cirrhosis, and failure to thrive. The first three types of PFICs identified (PFIC1, PFIC2, and PFIC3) represent defects in FIC1 (ATP8B1), BSEP (ABCB11), or MDR3 (ABCB4). In the last 5 years, new genetic disorders, such as TJP2, FXR, and MYO5B defects, have been demonstrated to cause a similar PFIC phenotype. Inborn errors of bile acid metabolism also cause progressive cholestatic liver injuries. Prompt differential diagnosis is important because oral primary bile acid replacement may effectively reverse liver failure and restore liver functions. DCDC2 is a newly identified genetic disorder causing neonatal sclerosing cholangitis. Other cholestatic genetic disorders may have extra-hepatic manifestations, such as developmental disorders causing ductal plate malformation (Alagille syndrome, polycystic liver/kidney diseases), mitochondrial hepatopathy, and endocrine or chromosomal disorders. The diagnosis of genetic liver diseases has evolved from direct sequencing of a single gene to panel-based next generation sequencing. Whole exome sequencing and whole genome sequencing have been actively investigated in research and clinical studies. Current treatment modalities include medical treatment (ursodeoxycholic acid, cholic acid or chenodeoxycholic acid), surgery (partial biliary diversion and liver transplantation), symptomatic treatment for pruritus, and nutritional therapy. New drug development based on gene-specific treatments, such as apical sodium-dependent bile acid transporter (ASBT) inhibitor, for BSEP defects are underway.

Short conclusion

Understanding the complex pathways of jaundice and cholestasis not only enhance insights into liver pathophysiology but also elucidate many causes of genetic liver diseases and promote the development of novel treatments.

Interleukin-8: A critical chemokine in biliary atresia

Biliary atresia (BA) is characterized by periductular inflammation and fibrosis and is associated with the progressive obliteration of the bile ducts. The induction and maintenance of systemic and local inflammatory responses plays a pivotal role in this process. Interleukin-8 (IL-8) is an important mediator of inflammation and the immune response in human disease. IL-8 is overexpressed in BA, and its expression positively correlates with inflammation and liver fibrosis. In this review, we focus on the available evidence, recent insights, and future clinical and preclinical possibilities regarding the role of IL-8 in BA.

Gene expression profiling of extrahepatic ducts in children with biliary atresia

As an inflammatory obliterative cholangiopathy of neonates, biliary atresia (BA) affects both intrahepatic and extrahepatic bile ducts. Its etiology has remained largely unknown. Gene expression profiling was conduced for extrahepatic bile duct tissues (including porta hepatis & common bile duct) to identify novel targets for further studies of BA. Among these tissues, porta hepatis was regarded as fibrosis group while common bile duct as self-control group. The analysis of gene expression profile in these tissues was performed with Affymetrix human microarray. Quantitative RT-PCR (qRT-PCR) was performed to confirm these results. The differential expressions of genes were identified through fold-change filtering. Gene Ontology (GO) and pathway analyses were performed using standard enrichment computation method. It was found that a total of 140 genes were differentially expressed between porta hepatis and common bile duct tissues, 19 genes up-regulated and 121 genes down-regulated. Moreover, GO analysis found that cell adhesion molecules, extracellular matrix formation, protein digestion & absorption functions may be involved in the pathogenesis of porta hepatis fibrosis. Lastly the qRT-PCR data confirmed that IL7 and CLDN2 were significantly up-regulated and both might be involved in the etiology of BA, the expression level of VCAM1 was positively correlated with severity of liver fibrosis in the BA infants. Our results demonstrated that the expressions of these aberrant genes responding to fibrosis in porta hepatis of patients with BA. Further studies of these genes may provide useful insights into the pathological mechanisms of BA.

Cirrhosis in children and adolescents: An overview

Several conditions, especially chronic liver diseases, can lead to cirrhosis in children and adolescents. Most cases in clinical practice are caused by similar etiologies. In infants, cirrhosis is most often caused by biliary atresia and genetic-metabolic diseases, while in older children, it tends to result from autoimmune hepatitis, Wilson's disease, alpha-1-antitrypsin deficiency and primary sclerosing cholangitis. The symptoms of cirrhosis in children and adolescents are similar to those of adults. However, in pediatric patients, the first sign of cirrhosis is often poor weight gain. The complications of pediatric cirrhosis are similar to those observed in adult patients, and include gastrointestinal bleeding caused by gastroesophageal varices, ascites and spontaneous bacterial peritonitis. In pediatric patients, special attention should be paid to the nutritional alterations caused by cirrhosis, since children and adolescents have higher nutritional requirements for growth and development. Children and adolescents with chronic cholestasis are at risk for several nutritional deficiencies. Malnutrition can have severe consequences for both pre- and post-liver transplant patients. The treatment of cirrhosis-induced portal hypertension in children and adolescents is mostly based on methods developed for adults. The present article will review the diagnostic and differential diagnostic aspects of end-stage liver disease in children, as well as the major treatment options for this condition.

miR-222 overexpression may contribute to liver fibrosis in biliary atresia by targeting PPP2R2A

OBJECTIVE

Biliary atresia (BA) is a devastating liver disease in infants. Progressive hepatic fibrosis is often observed in postoperative patients with BA even after a successful Kasai portoenterostomy procedure. MicroRNA-222 (miRNA) has been linked to the activation of stellate cells and the progression of liver fibrosis.

METHODS

In this study, the miR-222 expression profile in BA and infants with anicteric choledochal cyst (CC) was determined. The functional effect of miR-222 inhibition on the growth of the human hepatic stellate cell line LX-2 was also evaluated. The downstream signaling pathways and target of miR-222 were determined by coupling gene expression profiling and pathway analysis and by in silico prediction, respectively. In addition, we demonstrated miR-222 overexpression in patients with BA compared with choledochal cyst controls.

RESULTS

Inhibition of miR-222 in the LX-2 cell line significantly decreased cell proliferation. We also identified protein phosphatase 2A subunit B as a target of miR-222. The downstream signaling pathway, Akt, was also influenced by miR-222. A consistent reduction of Akt phosphorylation and Ki67 in the LX-2 line was shown following miR-222 suppression.

CONCLUSIONS

Our results show that miR-222 overexpression is common in BA and contributes to LX-2 cell proliferation by targeting protein phosphatase 2A subunit B and Akt signaling.

Using volume index and lateral hepatic angle to differentiate biliary atresia from TPN-associated cholestasis

OBJECTIVES

Differential diagnosis between biliary atresia (BA) and total parenteral nutrition-associated cholestasis (TPN-AC) and early treatment for cholestatic infants are challenges for evaluating neonatal or infantile cholestasis. The aim of our retrospective study was to apply noninvasive indices of magnetic resonance images to differentiate BA from TPN-AC.

METHODS

A total of 44 patients diagnosed as having BA (n = 30) or TPN-AC (n = 14) were included in the present retrospective study and underwent abdominal magnetic resonance imaging to evaluate the possibility of BA. The left lateral hepatic angle was determined from the coronal image of the left portal vein and portal vein of segment II. Adjusted volume indices of the right hepatic lobe (AVIR) and left lateral segment (AVILL) were calculated as the product of 3 diameters (centimeters) divided by each patient's body weight.

RESULTS

The left lateral hepatic angles of patients with BA (74° ± 21°) were significantly larger than for patients with TPN-AC (33° ± 9°) and controls (36° ± 5°, P < 0.05). AVILL of the BA (0.037 ± 0.012 cm/g) and TPN-AC groups (0.042 ± 0.030 cm/g) were not significantly different (P = 0.61) but were significantly larger than for controls (0.020 ± 0.011 cm/g) (P < 0.05). The right hepatic lobe to left lateral hepatic segment ratio (RLR) of patients with BA was significantly (P < 0.05) smaller (1.61 ± 0.58) than for patients with TPN-AC (3.08 ± 2.43) and controls (2.98 ± 0.92). Patients with BA could have relative sparing and selective enlargement of the left lateral liver with a resultant lobar difference and blunt left lateral hepatic angle.

CONCLUSIONS

Noninvasive indices of lobar difference and left lateral hepatic angle help differentiate patients with BA from those with TPN-AC.

A novel keratin18 promoter that drives reporter gene expression in the intrahepatic and extrahepatic biliary system allows isolation of cell-type specific transcripts from zebrafish liver

Heritable and acquired biliary disorders are an important cause of acute and chronic human liver disease. Biliary development and physiology have been studied extensively in rodent models and more recently, zebrafish have been used to uncover pathogenic mechanisms and potential therapies for these conditions. Here we report development of novel transgenic lines labeling the intrahepatic and extrahepatic biliary system of zebrafish larvae that can be used for lineage tracing and isolation of biliary-specific RNAs from mixed populations of liver cells. We show that GFP expression driven by a 4.4 kilobase promoter fragment from the zebrafish keratin18 (krt18) gene allows visualization of all components of the developing biliary system as early as 3 days post-fertilization. In addition, expression of a ribosomal fusion protein (EGFP-Rpl10a) in krt18:TRAP transgenic fish allows for enrichment of translated biliary cell mRNAs via translating ribosome affinity purification (TRAP). Future studies utilizing these reagents will enhance our understanding of the morphologic and molecular processes involved in biliary development and disease.

Improved outcome of biliary atresia with postoperative high-dose steroid

Objective. The dosage, duration, and the benefits of high-dose steroid treatment and outcome in biliary atresia (BA) remain controversial. In this study, we evaluated the impact of high-dose steroid therapy on the outcome of BA after the Kasai procedure. Methods. Intravenous prednisolone administration was started 1 week after surgery, followed by 8 to 12 weeks of oral prednisolone. Total bilirubin (TB) levels (3, 6, and 12 months after surgery), early onset of cholangitis, and two-year native liver survival were evaluated. Results. 53.4%, 56.9%, and 58.1% of the patients in the high-dose steroid group were jaundice-free 3, 6, and 12 months after surgery, respectively; these values were significantly higher than the 38.7%, 39.4%, and 43.3% of the low-dose steroid group. One year after surgery, the incidence of cholangitis in the high-dose group (32.0%) was lower than that in the low-dose group (48.0%). Infants with native liver in the high-dose group had a better two-year survival compared to those in the low-dose steroid group (53.7% versus 42.6%). Conclusions. The high-dose steroid protocol can reduce the incidence of cholangitis, increase the jaundice-free rate, and improve two-year survival with native liver after the Kasai operation.

p53-mediated biliary defects caused by knockdown of cirh1a, the zebrafish homolog of the gene responsible for North American Indian Childhood Cirrhosis

North American Indian Childhood Cirrhosis (NAIC) is a rare, autosomal recessive, progressive cholestatic disease of infancy affecting the Cree-Ojibway first Nations of Quebec. All NAIC patients are homozygous for a missense mutation (R565W) in CIRH1A, the human homolog of the yeast nucleolar protein Utp4. Utp4 is part of the t-Utp subcomplex of the small subunit (SSU) processome, a ribonucleoprotein complex required for ribosomal RNA processing and small subunit assembly. NAIC has thus been proposed to be a primary ribosomal disorder (ribosomopathy); however, investigation of the pathophysiologic mechanism of this disease has been hindered by lack of an animal model. Here, using a morpholino oligonucleotide (MO)-based loss-of-function strategy, we have generated a model of NAIC in the zebrafish, Danio rerio. Zebrafish Cirhin shows substantial homology to the human homolog, and cirh1a mRNA is expressed in developing hepatocytes and biliary epithelial cells. Injection of two independent MOs directed against cirh1a at the one-cell stage causes defects in canalicular and biliary morphology in 5 dpf larvae. In addition, 5 dpf Cirhin-deficient larvae have dose-dependent defects in hepatobiliary function, as assayed by the metabolism of an ingested fluorescent lipid reporter. Previous yeast and in vitro studies have shown that defects in ribosome biogenesis cause stabilization and nuclear accumulation of p53, which in turn causes p53-mediated cell cycle arrest and/or apoptosis. Thus, the nucleolus appears to function as a cellular stress sensor in some cell types. In accordance with this hypothesis, transcriptional targets of p53 are upregulated in Cirhin-deficient zebrafish embryos, and defects in biliary function seen in Cirhin-deficient larvae are completely abrogated by mutation of tp53. Our data provide the first in vivo evidence of a role for Cirhin in biliary development, and support the hypothesis that congenital defects affecting ribosome biogenesis can activate a cellular stress response mediated by p53.

α-SMA overexpression associated with increased liver fibrosis in infants with biliary atresia

OBJECTIVE

The mechanisms responsible for increased collagen production and hepatic fibrosis in biliary atresia (BA) remain largely unknown. We evaluated α-smooth muscle actin (α-SMA) expression in liver and the porta hepatis in infants with BA.

METHODS

Immunohistochemical staining for α-SMA and CD68 in the BA liver and porta hepatis was performed. A semiquantitative 3-grade staging system was employed to estimate liver fibrosis. The densities of CD68 in BA liver and the levels of direct bilirubin were assessed in relation to α-SMA expression.

RESULTS

α-SMA was found to be overexpressed in epithelial cells and in periductular collagen fibers. The expression in infants with BA was higher than that in the control group (P < 0.05). The amount of α-SMA in BA was positively correlated with liver fibrosis scores (r = 0.549, P = 0.022). The levels of α-SMA in the liver of BA were negatively related with improvements in direct bilirubin levels, 3 months postoperatively (r = -0.653, P = 0.029). The correlation between the α-SMA and CD-68 expression was not significantly different (r = 0.444, P = 0.057).

CONCLUSIONS

The expression of α-SMA in BA liver is higher than that in contro1 group. α-SMA expression is negatively correlated with the reduction of direct bilirubin, 3 months postoperatively, probably due to fibrosis or cirrhosis affecting the entire biliary system.

Interleukin-33 overexpression is associated with gamma-glutamyl transferase in biliary atresia

Interleukin-33 (IL-33) plays a crucial role in inflammation. However, it is not clear whether IL-33 levels are of clinical significance for patients with biliary atresia (BA). The purpose of this study was to determine correlations between serum IL-33 levels and the clinicopathologic features of BA. Serum samples were collected from 18 BA infants, 12 nonicteric choledochal cyst (CC) infants with normal liver function, and 10 healthy controls (HCs). Serum IL-33 levels were measured with an enzyme-linked immunosorbent assay (ELISA). Routine liver function tests were performed on the serum samples. qRT-PCR and Western blot analysis were used to detect IL-33 expression in BA liver biopsy tissues. Hepatic lobule localization of IL-33 expression in the hepatic lobule was conducted by immunohistochemistry (IHC). IL-33 levels in serum collected from BA infants were significantly elevated in comparison with CC and HC patients. Furthermore, the elevated serum levels of IL-33 in BA infants were correlated with gamma-glutamyl transferase (GGT) levels. The expression of IL-33 mRNA and protein levels were up-regulated in BA liver biopsy tissues in comparison with CC patients. IHC analysis revealed increased positive immunostaining for IL-33 in BA liver tissues as compared to that in CC tissues. These results suggest that IL-33 may play an important role in the pathogenesis of BA. In addition, the correlation of serum IL-33 levels with GGT levels may provide a novel marker for the diagnosis of BA.

Changes in epigenetic regulation of CD4+ T lymphocytesin biliary atresia

Biliary atresia (BA) is a virus-induced autoimmune disease associated with abnormal DNA methylation patterns that contribute to disease presentation. This study examined DNA methylation patterns, changes to genes associated with methylation regulation, and changes to the autoimmune-related gene interferon gamma (IFN-γ) in CD4+ T cells from BA patients. We demonstrated that genomic DNA isolated from CD4+ T cells harvested from infants presenting with BA were hypomethylated relative to healthy controls. In addition, DNA methyltransferase (DNMT1) and DNMT3a mRNA levels were significantly lower in BA CD4+ T cells compared with controls and methyl-DNA-binding domain proteins (MBD1) mRNA expression (but not MBD4 detected at higher levels in BA patients), which was significantly lower in CD4+ T cells from BA infants than in controls. DNMT1 expression positively correlated with global DNA methylation in BA CD4+ T cells. IFN-γ mRNA expression levels in BA patients were also significantly increased, and the IFN-γ gene promoter region was hypomethylated in BA CD4+ T cells compared with controls and negatively correlated with DNA methylation. These data suggest that methylation changes in CD4+ cells may contribute to BA disease presentation and progression by affecting the expression of genes associated with autoimmunity.

A case of lipoid congenital adrenal hyperplasia presenting with cholestasis

BACKGROUND

Lipoid congenital adrenal hyperplasia, is the rarest and usually the most severe form of adrenal steroidogenic defect,which may presents as infantile cholestasis.

CASE PRESENTATION

Here we present a 45 days old infant who came to our attention with cholestasis and severe intractable vomiting and electrolyte disturbances. Evaluation resulted in diagnosis of congenital adrenal hyperplasia. Hydrocortisone and flodrocortisone improved the symptoms including jaundice and vomiting. Hyponatremia and hyperkalemia also resolved with above mentioned treatment.

CONCLUSION

Congenital adrenal hyperplasia as one of the causes of neonatal cholestasis should be kept in mind, whenever there are also electrolytes abnormalities.