Liver Disease Of Unknown Etiology Research Articles

Increased IgD and CD27 Double Negative (DN) B cell population in pediatric onset autoimmune hepatitis

Autoimmune hepatitis (AIH) is a chronic, inflammatory liver disease of unknown aetiology which requires lifelong immunosuppression. Most therapeutic and outcome studies of AIH have been conducted predominantly in Caucasian (European Ancestry, EA) cohorts, with the exclusion of African American (AA) patients due to inadequate sample size. It is known that AA patients have a severe phenotype of autoimmune diseases and demonstrate a poor response to conventional medical therapy. Understanding cellular and molecular pathways which determine AIH severity and progression in AA patients is likely to lead to the discovery of novel, personalised and better tolerated therapies. The aim of the study is to determine the distinct effector B cell phenotypes which contribute to disease severity and progression of AIH in AA children as compared to their EA cohorts. PBMCs were isolated from blood samples collected from patients visiting Children’s Healthcare of Atlanta (CHOA) and were grouped into AA, (n = 12), EA, (n = 11) and controls (n = 12) and were processed for flow cytometry. Markers of B cell development, maturation and activation were assessed namely CD19, CD21, IgD, CD27, CD38, CD11c, CD24, CD138. AA children with AIH demonstrated an expansion of CD19 + ve, Activated Naïve (aN), (CD19+ IgD-/CD27- Double Negative (DN2) ([CD19+/IgD-/CD27++CD38++) cells. Plasmablasts were significantly higher along with Signalling Lymphocytic activation molecule F7 (SLAMF7). Unswitched memory [CD19+] IgD+CD27+ (USM) B cells were significantly contracted in AA patients with AIH. B cell phenotyping reveals a distinct profile in AA AIH patients with a major skewing towards the expansion of effector pathways which have been previously characterised in severe SLE in AA patients. These results suggest that the quantification and therapeutic target of B cell pathway could contribute substantially to the clinical approach to AIH especially in the AA population.

Second- and third-line treatment agents in autoimmune hepatitis (AIH): Where do we stand?

Autoimmune hepatitis (AIH) is a chronic liver disease of unknown aetiology that can lead to end stage liver disease if left without treatment. Corticosteroids with or without azathioprine (AZA) are considered the recommended standard first-line treatment option for the induction and maintenance of remission. The aim of treatment is to achieve complete biochemical response (CBR), defined by normal transaminases and immunoglobulin G (IgG) within 6–12 months after treatment initiation. However, response rates to standard treatment vary widely as approximately 10–25% of cases develop intolerance, insufficient response, or rarely non-response to AZA. Mycophenolate mofetil (MMF) is an effective and safe alternative first-line treatment in AIH, based on its high rates of CBR among treatment-naive patients, but can also be considered as second-line drug in patients with poor response or intolerance to AZA. However, even after the administration of second line treatment there is a small proportion of patients with refractory disease that bear the highest probability of developing decompensated cirrhosis and hepatocellular carcinoma. For this difficult to treat subgroup of patients third-line treatments are warranted. Therefore, the aim of this review is to summarize the current evidence on second- and third-line therapies for AIH, as well as, to set the background for future perspectives on safer and more efficient treatment strategies.

STAT activation in regulatory CD4+ T cells of patients with primary sclerosing cholangitis.

Regulatory CD4+ T cells (Tregs) are pivotal for inhibition of autoimmunity. Primary sclerosing cholangitis (PSC) is an autoimmune cholestatic liver disease of unknown etiology where contribution of Tregs is still unclear. Activation of the JAK-STAT pathway critically modifies functions of Tregs. In PSC, we studied activation of STAT proteins and Treg functions in response to cytokines. In 51 patients with PSC, 10 disease controls (chronic replicative hepatitis C), and 36 healthy controls we analyzed frequencies of Foxp3+CD25+CD127lowCD4+ Tregs, their expression of ectonucleotidase CD39, and cytokine-induced phosphorylation of STAT1, 3, 5, and 6 using phospho-flow cytometry. In parallel, we measured cytokines IFN-gamma, interleukin (IL)-6, IL-2, and IL-4 in serum via bead-based immunoassays. In patients with PSC, ex vivo frequencies of peripheral Tregs and their expression of CD39 were significantly reduced (p < .05 each). Furthermore, serum levels of IFN-gamma, IL-6, IL-2, and IL-4 were markedly higher in PSC (p < .05 each). Unlike activation of STAT1, STAT5, and STAT6, IL-6 induced increased phosphorylation of STAT3 in Tregs of PSC-patients (p = .0434). Finally, STAT3 activation in Tregs correlated with leukocyte counts. In PSC, we observed enhanced STAT3 responsiveness of CD4+ Tregs together with reduced CD39 expression probably reflecting inflammatory activity of the disease.

Berberine alleviates concanavalin A-induced autoimmune hepatitis in mice by modulating the gut microbiota.

Autoimmune hepatitis (AIH) is an immune-mediated liver disease of unknown etiology accompanied by intestinal dysbiosis and a damaged intestinal barrier. Berberine (BBR) is a traditional antibacterial medicine that has a variety of pharmacological properties. It has been reported that BBR alleviates AIH, but relevant mechanisms remain to be fully explored. BBR was orally administered at doses of 100mg⋅kg-1⋅d-1 for 7 days to mice before concanavalin A-induced AIH model establishment. Histopathological, immunohistochemical, immunofluorescence, western blotting, ELISA, 16S rRNA analysis, flow cytometry, real-time quantitative PCR, and fecal microbiota transplantation studies were performed to ascertain BBR effects and mechanisms in AIH mice. We found that liver necrosis and apoptosis were decreased upon BBR administration; the levels of serum transaminase, serum lipopolysaccharide, liver proinflammatory factors TNF-α, interferon-γ, IL-1β, and IL-17A, and the proportion of Th17 cells in spleen cells were all reduced, while the anti-inflammatory factor IL-10 and regulatory T cell proportions were increased. Moreover, BBR treatment increased beneficial and reduced harmful bacteria in the gut. BBR also strengthened ileal barrier function by increasing the expression of the tight junction proteins zonula occludens-1 and occludin, thereby blocking lipopolysaccharide translocation, preventing lipopolysaccharide/toll-like receptor 4 (TLR4)/ NF-κB pathway activation, and inhibiting inflammatory factor production in the liver. Fecal microbiota transplantation from BBR to model mice also showed that BBR potentially alleviated AIH by altering the gut microbiota. BBR alleviated concanavalin A-induced AIH by modulating the gut microbiota and related immune regulation. These results shed more light on potential BBR therapeutic strategies for AIH.

Patients With Autoimmune Hepatitis and Nonalcoholic Fatty Liver Disease: Characteristics, Treatment, and Outcomes.

The objective of this study was to characterize an autoimmune hepatitis (AIH)/nonalcoholic fatty liver disease (NAFLD) overlap cohort, determine if they received standard of care treatment, and delineate their outcomes in comparison with patients with AIH or NAFLD alone. AIH is a relatively rare and heterogeneously presenting liver disease of unknown etiology. NAFLD is a leading cause of liver disease worldwide. AIH treatment includes steroids, which have adverse metabolic effects that can worsen NAFLD. No treatment guidelines are available to mitigate this side on AIH/NAFLD overlap patients. Few studies to date have examined these patients' characteristics, management practices, and outcomes. A single-center, retrospective chart review study examining biopsy-proven AIH/NAFLD, AIH, and NAFLD patients. Characteristics, treatment, and 1- and 3-year outcomes (all-cause mortality, need for liver transplantation, or decompensated cirrhosis) were evaluated. A total of 72 patients (36.1% AIH/NAFLD, 34.7% AIH, and 29.2% NAFLD) were included. AIH/NAFLD patients were found to be more often Hispanic/Latino, female, and with lower liver aminotransaminases, immunoglobulin G, and anti-smooth muscle antibody positivity. AIH/NAFLD patients were less likely to receive standard of care treatment. No significant differences in outcomes were seen between AIH/NAFLD and either AIH or NAFLD. Our study demonstrated that AIH/NAFLD patients have unique characteristics and are less likely to receive standard of care treatment compared with patients with AIH alone. Despite this, no difference in outcomes (all-cause mortality, need for liver transplantation, or decompensated cirrhosis) was seen. Given NAFLD's rising prevalence, AIH/NAFLD cases will likely increase, and may benefit from alternative treatment guidelines to prevent worsening of NAFLD.

Long-term clinical and socioeconomic outcomes of children with biliary atresia.

Biliary atresia (BA) is rare liver disease of unknown etiology, and is a major indication for liver transplant (LT). Previous data indicate improved outcomes with early referral for Kasai portoenterostomy (KPE). Evaluate the long-term outcomes in BA, with particular focus on those transitioned to adult care with native livers. Patients with BA treated between1980 and 2012 were identified. Data were collected from the time of referral, transition to adult care, and the most recent clinic notes, from which patient and native liver survival were calculated. Four hundred and fifty-four patients with BA were identified, who were followed up for median of 16.4 years from birth; 74 died (41 of whom had a LT), giving a 20-year survival rate of 83.6%. Two hundred and seventy-two patients received an LT, with the median native liver survival being 35 months. Of patients who transitioned to adult care, 54 of 180 (30.0%) retained their native liver. Of these, 72% (39 of 54) had evidence of chronic liver disease at transition, of whom 8 were subsequently lost to follow-up, 9 were transplanted, and 22 remained stable with compensated liver disease. Of the 15 of 54 patients (28%) with no evidence of chronic disease in their native liver disease at transition, 3 were subsequently lost to follow-up; none received transplants, although 3 patients developed new-onset liver disease. All patients transitioned to adult care completed secondary school education (N = 180), with 49% having attended college/university and 87% being in employment or education at the last follow-up. Of female patients, 34% had at least one pregnancy (27 children in 21 women), while 22% of males had fathered a child. Long-term outcomes in BA are good, with patients surviving into adult life. Progression of chronic liver disease and associated morbidity is common in those who retained their native livers, suggesting that these patients require monitoring of liver disease throughout adult life, and early recognition of the need for LT.

Incidence and predictors of hepatocellular carcinoma in patients with autoimmune hepatitis

Autoimmune hepatitis (AIH) is a rare chronic liver disease of unknown aetiology; the risk of hepatocellular carcinoma (HCC) remains unclear and risk factors are not well-defined. We aimed to investigate the risk of HCC across a multicentre AIH cohort and to identify predictive factors. We performed a retrospective, observational, multicentric study of patients included in the International Autoimmune Hepatitis Group Retrospective Registry. The assessed clinical outcomes were HCC development, liver transplantation, and death. Fine and Gray regression analysis stratified by centre was applied to determine the effects of individual covariates; the cumulative incidence of HCC was estimated using the competing risk method with death as a competing risk. A total of 1,428 patients diagnosed with AIH from 1980 to 2020 from 22 eligible centres across Europe and Canada were included, with a median follow-up of 11.1 years (interquartile range 5.2-15.9). Two hundred and ninety-three (20.5%) patients had cirrhosis at diagnosis. During follow-up, 24 patients developed HCC (1.7%), an incidence rate of 1.44 cases/1,000 patient-years; the cumulative incidence of HCC increased over time (0.6% at 5 years, 0.9% at 10 years, 2.7% at 20 years, and 6.6% at 30 years of follow-up). Patients who developed cirrhosis during follow-up had a significantly higher incidence of HCC. The cumulative incidence of HCC was 2.6%, 4.6%, 5.6% and 6.6% at 5, 10, 15, and 20 years after the development of cirrhosis, respectively. Obesity (hazard ratio [HR] 2.94, p=0.04), cirrhosis (HR 3.17, p=0.01), and AIH/PSC variant syndrome (HR 5.18, p=0.007) at baseline were independent risk factors for HCC development. HCC incidence in AIH is low even after cirrhosis development and is associated with risk factors including obesity, cirrhosis, and AIH/PSC variant syndrome. The risk of developing hepatocellular carcinoma (HCC) in individuals with autoimmune hepatitis (AIH) seems to be lower than for other aetiologies of chronic liver disease. Yet, solid data for this specific patient group remain elusive, given that most of the existing evidence comes from small, single-centre studies. In our study, we found that HCC incidence in patients with AIH is low even after the onset of cirrhosis. Additionally, factors such as advanced age, obesity, cirrhosis, alcohol consumption, and the presence of the AIH/PSC variant syndrome at the time of AIH diagnosis are linked to a higher risk of HCC. Based on these findings, there seems to be merit in adopting a specialized HCC monitoring programme for patients with AIH based on their individual risk factors.

Advancing diagnosis and management of liver disease in adults through exome sequencing

Whole-exome sequencing (WES) is an effective tool for diagnosis in patients who remain undiagnosed despite a comprehensive clinical work-up. While WES is being used increasingly in pediatrics and oncology, it remains underutilized in non-oncological adult medicine, including in patients with liver disease, in part based on the faulty premise that adults are unlikely to harbor rare genetic variants with large effect size. Here, we aim to assess the burden of rare genetic variants underlying liver disease in adults at two major tertiary referral academic medical centers. WES analysis paired with comprehensive clinical evaluation was performed in fifty-two adult patients with liver disease of unknown etiology evaluated at two US tertiary academic health care centers. Exome analysis uncovered a definitive or presumed diagnosis in 33% of patients (17/52) providing insight into their disease pathogenesis, with most of these patients (12/17) not having a known family history of liver disease. Our data shows that over two-thirds of undiagnosed liver disease patients attaining a genetic diagnosis were being evaluated for cholestasis or hepatic steatosis of unknown etiology. This study reveals an underappreciated incidence and spectrum of genetic diseases presenting in adulthood and underscores the clinical value of incorporating exome sequencing in the evaluation and management of adults with liver disease of unknown etiology. S.V. is supported by the NIH/NIDDK (K08 DK113109 and R01 DK131033-01A1) and the Doris Duke Charitable Foundation Grant #2019081. This work was supported in part by NIH-funded Yale Liver Center, P30 DK34989.

Poor Access to Liver Transplantation and Survival of Children With Acute Liver Failure, Acute-on-chronic Liver Failure or Chronic Liver Disease.

We describe the survival of children with acute liver failure (ALF), chronic liver disease (CLD), or acute-on-chronic liver failure (ACLF) with poor access to liver transplantation (LT). A retrospective cohort study of 42 patients <18 years of age was conducted in the Hospital Civil de Guadalajara "Dr. Juan I. Menchaca". The median age was 76 months; 57.1% were female, 40.5% presented with ALF, 35.7% with CLD, and 23.8% with ACLF. Also, 38.1% (16/42) presented liver disease of unknown etiology. Death occurred in 45.2%; 14.3% were transferred to another hospital, and none received LT. Mortality in ALF, CLD, and ACLF was 76%, 0%, and 60%, respectively. In the survival analysis, within the first 20 months after diagnosis, the mortality rate was greater than 50% with ALF. The importance of having referral programs that perform liver transplantation is highlighted by the poor prognosis of the patients, despite conservative treatment.

Cryptogenic chronic hepatitis: looking for an ideal diagnostic algorithm

IntroductionCryptogenic chronic hepatitis is a growing cause of liver transplants, affecting 5%–15% of patients with chronic liver diseases. This study aimed to identify underlying causes of cryptogenic liver disease in a Brazilian cohort and propose a new diagnostic algorithm, including investigation for metabolic-dysfunction-associated fatty liver disease (MAFLD) and lysosomal acid lipase deficiency (LAL-D).MethodsA retrospective analysis was conducted on 326 patients with presumed cryptogenic hepatitis.ResultsUsing Czaja’s algorithm, non-alcoholic fatty liver disease was diagnosed in 21.3% of patients, while alpha-1 antitrypsin deficiency, alcoholic liver disease, autoimmune hepatitis, hemochromatosis, biliary-related hepatitis, viral hepatitis, Budd–Chiari syndrome, glycogenosis, drug-induced liver injury, and Wilson’s disease were diagnosed in smaller proportions (&amp;lt; 3.5% each). LAL-D was found in 1% of patients, and 53.6% of patients remained with cryptogenic hepatitis. The etiology of the liver disease in a subset of patients undergoing liver transplantation was updated post hoc based on explant histology, and non-alcoholic steatohepatitis was found in 52.5% of patients. By incorporating the concept of MAFLD, the new algorithm could diagnose 49.1% of patients, reducing the number of individuals without an etiological diagnosis by 11.4%.ConclusionOne-third of patients with initially presumed cryptogenic liver disease were diagnosed with MAFLD. LAL-D should be considered in patients with chronic liver disease of unknown etiology. The updated diagnostic algorithm proposed in this study could improve diagnostic accuracy and aid in the management of patients with cryptogenic hepatitis.

Exome sequencing reveals IFT172 variants in patients with non-syndromic cholestatic liver disease.

Gene defects contribute to the aetiology of intrahepatic cholestasis. We aimed to explore the outcome of whole-exome sequencing (WES) in a cohort of 51 patients with this diagnosis. Both paediatric (n = 33) and adult (n = 18) patients with cholestatic liver disease of unknown aetiology were eligible. WES was used for reassessment of 34 patients (23 children) without diagnostic genotypes in ABCB11, ATP8B1, ABCB4 or JAG1 demonstrable by previous Sanger sequencing, and for primary assessment of additional 17 patients (10 children). Nasopharyngeal swab mRNA was analysed to address variant pathogenicity in two families. WES revealed biallelic variation in 3 ciliopathy genes (PKHD1, TMEM67 and IFT172) in 4 clinically unrelated index subjects (3 children and 1 adult), heterozygosity for a known variant in PPOX in one adult index subject, and homozygosity for an unreported splice-site variation in F11R in one child. Whereas phenotypes of the index patients with mutated PKHD1, TMEM67, and PPOX corresponded with those elsewhere reported, how F11R variation underlies liver disease remains unclear. Two unrelated patients harboured different novel biallelic variants in IFT172, a gene implicated in short-rib thoracic dysplasia 10 and Bardet-Biedl syndrome 20. One patient, a homozygote for IFT172 rs780205001 c.167A>C p.(Lys56Thr) born to first cousins, had liver disease, interpreted on biopsy aged 4y as glycogen storage disease, followed by adult-onset nephronophthisis at 25y. The other, a compound heterozygote for novel frameshift variant IFT172 NM_015662.3 c.2070del p.(Met690Ilefs*11) and 2 syntenic missense variants IFT172 rs776310391 c.157T>A p.(Phe53Ile) and rs746462745 c.164C>G p.(Thr55Ser), had a severe 8mo cholestatic episode in early infancy, with persisting hyperbilirubinemia and fibrosis on imaging studies at 17y. No patient had skeletal malformations. Our findings suggest association of IFT172 variants with non-syndromic cholestatic liver disease.

Alcohol intake is associated with a decreased risk of developing primary biliary cholangitis.

BACKGROUNDPrimary biliary cholangitis (PBC) is a chronic progressive liver disease of unknown aetiology characterised by immune-mediated destruction of small and medium-sized intrahepatic bile ducts. There are few well-established risk factors and epidemiological studies are needed to further evaluate the pathogenesis of the disease. AIMTo evaluate the relationship between alcohol intake, smoking and marijuana use with PBC development. METHODSWe conducted a prevalent case control study of 200 cases and 200 age (within a five year age band) and sex-matched controls, identified from the Victorian PBC prevalence study. We assessed lifetime alcohol intake and smoking behaviour (both tobacco and marijuana) prior to PBC onset and used conditional logistic regression for analyses. RESULTSAlcohol intake consistently showed a dose-dependent inverse association with case status, and this was most substantial for 21-30 years and 31-40 years (Ptrend < 0.001). Smoking was associated with PBC, with a stronger association with a longer duration of smoking [e.g., adjusted OR 2.27 (95%CI: 1.12- 4.62) for those who had smoked for 20-35 years]. There was no association between marijuana use and PBC. CONCLUSIONAlcohol appears to have an inverse relationship with PBC. Smoking has been confirmed as an environmental risk factor for PBC. There was no association between marijuana use and PBC.

DHEA Protects Human Cholangiocytes and Hepatocytes against Apoptosis and Oxidative Stress.

Primary biliary cholangitis (PBC) is a rare chronic cholestatic and immune-mediated liver disease of unknown aetiology that targets intrahepatic bile duct cells (cholangiocytes) and primarily affects postmenopausal women, when their estrogen levels sharply decrease. An impaired cholangiocyte response to estrogen characterizes the terminal stage of the disease, as this is when an inefficiency of cholangiocyte proliferation, in balancing the loss of intrahepatic bile ducts, is observed. Here, we report that the estrogen precursor dehydroepiandrosterone (DHEA) and its sulfate metabolites, DHEA-S and 17 β-estradiol, enhance the proliferation of cholangiocytes and hepatocytes in vitro. Flow cytometry analysis showed that DHEA and DHEA-S decreased glyco-chenodeoxycholic acid (GCDC)-driven apoptosis in cholangiocytes. Cell viability assay (MTT) indicated that ER-α, -β, and the G-protein-coupled estrogen receptor, are involved in the protection of DHEA against oxidative stress in cholangiocytes. Finally, immunoblot analysis showed an elevated level of steroid sulfatase and a reduced level of sulfotransferase 1E1 enzymes, involved in the desulfation/sulfation process of estrogens in cirrhotic PBC, and primary sclerosis cholangitis (PSC) liver tissues, another type of chronic cholestatic and immune-mediated liver disease. Taken together, these results suggest that DHEA can prevent the deleterious effects of certain potentially toxic bile acids and reactive oxygen species, delaying the onset of liver disease.

Autoimmune hepatitis as the first manifestation of autoimmune polyendocrine syndrome type 1 in a 5-year-old girl

Autoimmune hepatitis is a chronic inflammatory liver disease of unknown etiology; the prevalence of juvenile autoimmune hepatitis is unknown. Autoimmune hepatitis occurs in 10–20% of patients with type 1 autoimmune polyendocrine syndrome, a rare (orphan) disease, which is characterized by a clinical triad in 70–100% of cases: chronic mucocutaneous candidiasis, hypopara thy roidismand adrenal insufficiency, as well as more 25 possible autoimmune endocrine and non-endocrine manifestations.Thisstudy describes a case of a 5-year-old girl with autoimmune hepatitis as the first clinical manifestation of the disease. The symptoms of chronic mucocutaneous candidiasis enabled us to suggest and genetically confirm the diagnosis of autoimmune poly endocrine syndrome type 1 before the lesions of endocrine organs. The girl had nonsense mutations R257 * and p.Q94* of the AIRE gene in a compound heterozygous state. Later, there appeared another autoimmune disorder – common vitiligo.Timelydiagnosisoftype1autoimmunepolyendocrinesyndromeinachildwiththefirstnon-endocrine autoimmune manifestation, initiation of therapy and further medical management made it possible to preventseve recomplications and improve the patient’s quality of life.

O-8 THE IMPORTANCE OF LYSOSOMAL ACID LIPASE DEFICIENCY IN THE ETIOLOGICAL INVESTIGATION OF CRYPTOGENIC LIVER DISEASE IN ADULTS: A MULTICENTER STUDY

Lysosomal acid lipase deficiency (LAL-D) is a rare genetic disease associated with lipid metabolism deregulation leading to atherosclerosis, dyslipidemia, and hepatic steatosis, with potential progression to cirrhosis. Investigation of LAL-D in patients with chronic liver disease is not routinely performed in most centers. The aim of this study was to evaluate whether it is worthwhile to investigate LAL-D in patients with liver disease of unknown etiology, and if there is any particular population that this search should be focused. This was a multicenter cross-sectional study in 295 patients followed with presumed cryptogenic liver disease from four tertiary centers in Brazil. Clinical, demographic and laboratory data from participants were assessed, with the exclusion of all known causes of liver disease. All patients were submitted to the investigation of LAL enzyme activity. The exams were collected on dried blood spot (DBS). A total of 135 patients were included in the study. Three patients (2.22%) presented values of LAL below the reference limit, compatible with LAL-D. The mean age of these patients was 43.9±10.1 years, of which 2 were females. The mean BMI was 24.3±0.7 and mean serum glycemia was 89.7±3.2 mg/dL. The mean serum HDL and triglycerides were 21.7±3.2 mg/dL and 206.7±25.5 mg/dL, respectively. Despite being a rare disease, also in our study population, LAL-D investigation may be considered in those individuals without overweight with reduced serum HDL and elevated triglycerides levels and chronic liver disease of unknown etiology.

Gut microbiota depletion exacerbates cholestatic liver injury via loss of FXR signalling.

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease of unknown aetiology for which there are no approved therapeutic options. Patients with PSC display changes in gut microbiota and in bile acid (BA) composition; however, the contribution of these alterations to disease pathogenesis remains controversial. Here we identify a role for microbiota-dependent changes in BA synthesis that modulates PSC pathophysiology. In a genetic mouse model of PSC, we show that loss of microbiota-mediated negative feedback control of BA synthesis results in increased hepatic BA concentrations, disruption of bile duct barrier function and, consequently, fatal liver injury. We further show that these changes are dependent on decreased BA signalling to the farnesoid X receptor, which modulates the activity of the rate-limiting enzyme in BA synthesis, CYP7A1. Moreover, patients with advanced stages of PSC show suppressed BA synthesis as measured by serum C4 levels, which is associated with poor disease prognosis. Our preclinical data highlight the microbiota-dependent dynamics of BA metabolism in cholestatic liver disease, which could be important for future therapies targeting BA and gut microbiome interactions, and identify C4 as a potential biomarker to functionally stratify patients with PSC and predict disease outcomes.

Co-expression gene network analysis reveals novel regulatory pathways involved in porto-sinusoidal vascular disease

Porto-sinusoidal vascular disease (PSVD) is a rare vascular liver disease of unknown etiology that causes portal hypertension. It usually affects young individuals and shortens live expectancy. The deregulated pathways involved in PSVD development are unknown and therefore we lack curative treatments. The purpose of this study was to integrate transcriptomic and clinical data by comprehensive network-based modeling in order to uncover altered biological processes in patients with PSVD. We obtained liver tissue samples from 20 consecutive patients with PSVD and 21 sex- and age-matched patients with cirrhosis and 13 histologically normal livers (HNL) (initial cohort) and performed transcriptomic analysis. Microarray data were analyzed using weighted gene correlation network analysis to identify clusters of highly correlated genes differently expressed in patients with PSVD. We next evaluated the molecular pathways enriched in patients with PSVD and the core-related genes from the most significantly enriched pathways in patients with PSVD. Our main findings were validated using RNA sequencing in a different cohort of PSVD, cirrhosis and HNL (n= 8 for each group). Patients with PSVD have a distinctive genetic profile enriched mainly in canonical pathways involving hemostasis and coagulation but also lipid metabolism and oxidative phosphorylation. Serpin family (SERPINC1), the apolipoproteins (APOA, APOB, APOC), ATP synthases (ATP5G1, ATP5B), fibrinogen genes (FGB, FGA) and alpha-2-macroglobulin were identified as highly connective genes that may have an important role in PSVD pathogenesis. PSVD has a unique transcriptomic profile and we have identified deregulation of pathways involved in vascular homeostasis as the main pathogenic event of disease development. Porto-sinusoidal vascular disease is a rare but life-shortening disease that affects mainly young people. Knowledge of the disrupted pathways involved in its development will help to identify novel therapeutic targets and new treatments. Using a systems biology approach, we identify that pathways regulating endothelial function and tone may act as drivers of porto-sinusoidal vascular disease.

Giant cell hepatitis associated with autoimmune hemolytic anemia: an update

Giant cell hepatitis associated with autoimmune hemolytic anemia (GCH-AHA) is a rare and severe disease characterized by autoimmune hemolysis associated with acute liver injury, histologically defined by widespread giant cell transformation. It occurs after the neonatal period, most commonly in the first year of life and uniquely affects pediatric patients. It is still poorly understood and likely underdiagnosed, although in recent years there have been advances in the understanding of its pathogenesis and the liver injury is now hypothesized to be secondary to a humoral immune mechanism. Although no laboratory test specific for the diagnosis currently exists, given its severity, it is fundamental to rule out GCH-AHA when evaluating a patient in the first year of life presenting with AHA and/or with acute liver disease of unknown etiology. While GCH-AHA is progressive in nature as other autoimmune liver disorders, it differs significantly from juvenile autoimmune hepatitis (JAIH) in that a cure can be achieved after several years of intensive treatment in a portion of patients. Conventional first line therapy consist of prednisone/prednisolone combined with azathioprine, however, several immunosuppressive drugs, commonly used in the treatment of JAIH have been tried as second line therapy, including cyclosporine, cyclophosphamide, mycophenolate mofetil, 6-mercaptopurine, calcineurin inhibitors, and sirolimus. Intravenous immunoglobulins have also been used in cases of severe liver dysfunction and/or severe anemia allowing for transitory remission. More recently treatment with B-cell depletion has been attempted in some patients and encouraging results have been reported in refractory cases. Although what constitutes optimal treatment has yet to be determined, the recent progress in the understanding of the pathogenetic mechanisms of GCH-AHA have made positive strides, cautiously pointing toward a hopeful prognosis for some of these patients.

Progressive familial intrahepatic cholestasis type 3: Report of four clinical cases, novel ABCB4 variants and long-term follow-up

Introduction and objectivesProgressive familial intrahepatic cholestasis type 3 (PFIC-3) is a rare autosomal recessive cholestatic liver disorder caused by mutations in the ABCB4 gene. The aim of this study was to present the phenotypic and genotypic spectrum of 4 Polish PFIC-3 patients diagnosed in a one-referral centre. Materials and methodsThe study included 4 patients with cholestasis and pathogenic variants in the ABCB4 gene identified by next-generation sequencing (NGS) of a targeted-gene panel or whole exome sequencing (WES). Clinical, laboratory, histological, and molecular data were collected. ResultsFour patients (three males) were identified. The age at first noted clinical signs and symptoms was 6, 2.5, 14, and 2 years respectively; the mean age was 6 years. Those signs and symptoms include pruritus (2 out of 4 patients) and hepatomegaly with splenomegaly (4 out of 4 patients). The age at the time of referral to our centre was 9, 3, 15, and 2.5 years respectively, while the mean age was 7 years. Chronic cholestatic liver disease of unknown aetiology was established in all of them. The NGS analysis was performed in all patients at the last follow-up visit. Three novel variants including c.902T>A, p.Met301Lys, c.3279+1G>A, p.?, and c.3524T>A, p.Leu1175His were identified. The time from the first consultation to the final diagnosis was 14, 9, 3, and 1 year respectively; the mean was 6.8 years. A detailed follow-up was presented. ConclusionsThe clinical phenotype of PFIC-3 could be variable. The clinical and biochemical diagnosis of PFIC-3 is difficult, thus the NGS study is very useful in making a proper diagnosis.

Limitation of the simplified scoring system for the diagnosis of autoimmune Hepatitis with acute onset.

Autoimmune Hepatitis (AIH) is a chronic inflammatory liver disease of unknown aetiology characterized by the presence of autoantibodies, hypergammaglobulinaemia with specific IgG increase and interface hepatitis on liver histology. The clinical course of AIH is classically characterized by fluctuating periods of decreased or increased disease activity and therefore its clinical spectrum is variable ranging from no symptoms to severe acute hepatitis and even fulminant hepatic failure. Acute presentation may not differ from acute hepatitis of other causes and diagnosis can be difficult. We describe our experience on diagnostic performance of the two AIH scoring systems in acute onset of AIH and found that revised version of the original criteria (1999) achieves the diagnosis in about 30% of patients who presented with normal IgG serum levels and lower frequency of autoantibody positivity in whom the simplified score did not allow the diagnosis.