Primary sclerosing cholangitis: a review of its clinical features, cholangiography, and hepatic histology

Gamma-glutamyltransferase testing in paediatric inflammatory bowel disease to screen for primary sclerosing cholangitis: a diagnostic study based on routinely collected electronic healthcare data

OBJECTIVE

To investigate, among children with inflammatory bowel disease (IBD) and elevated liver enzymes, what threshold of gamma-glutamyltransferase (GGT) best distinguishes those with and without primary sclerosing cholangitis (PSC).

METHOD

Delayed-type diagnostic study with a paired design. Children with IBD were regularly screened with GGT (index test). Confirmation of PSC was based on magnetic resonance cholangiopancreatography (MRCP) and/or liver histology (preferred reference standard). Children at low risk of PSC continued regular GGT testing for latent PSC to become visible (alternative reference test). The primary outcome was the negative predictive value (NPV) using three predefined test thresholds, respectively, 1, 2 and 5× the upper limit of normal (ULN). The secondary outcome was the GGT threshold based on receiver operating characteristic analysis.

RESULTS

132 of 469 children (28.1%) had elevated GGT levels at their first colonoscopy or during follow-up. Eventually, 34 children (7.2%) were diagnosed with PSC. Median GGT (IQR) for children with and without PSC was 227 (127-345) and 77 (59-138) U/L, respectively. Of the predefined GGT thresholds, 2× ULN (ie, 100 U/L) had the best test characteristics, including an NPV of 98% and a negative likelihood ratio of 0.04 (95% CI 0.01 to 0.31). The area under the curve was 0.83 (95% CI: 0.75 to 0.90) and the optimal GGT threshold was 103.5 U/L.

CONCLUSION

In children with IBD who have GGT elevations less than 2× ULN, the likelihood of PSC is extremely low. In such cases, MRCP and liver biopsy can be omitted. Regular GGT monitoring is advised, as PSC may develop over time.

Treatment of pruritus in primary sclerosing cholangitis: Analysis of the consortium for autoimmune liver disease registry

BACKGROUND

Cholestasis from primary sclerosing cholangitis (PSC) frequently causes pruritus. However, the prevalence of pruritus and its management have not been well studied. Investigating the Cholestatic Pruritus of Primary Sclerosing Cholangitis (ItCh-PSC) includes a retrospective medical record review to determine the prevalence, severity, and treatment patterns of pruritus.

METHODS

Data was collected at 5 academic medical centers in the United States. Medical records were searched for the terms "itch" and "pruritus" and data abstracted related to itch severity, number of encounters, and treatment.

RESULTS

Among 724 patients with PSC, 359 (50%) of patients had a documented history of pruritus, including 40%, 39%, and 21% with mild, moderate, or severe itch. Itch was less common in those with small ducts compared to large duct PSC (p=0.02) and more frequent in those of Hispanic versus non-Hispanic ethnicity (p=0.001). Compared to patients with mild itch, patients with moderate or severe itch were younger, and had more elevated liver biochemistries, more encounters with itch, and more frequently prescribed 2 or more anti-pruritic medications. Bile acid-binding resins were prescribed in 36%, hydroxyzine in 23%, rifampin in 11%, and fenofibrate in 4% of patients with any itch. The prevalence and severity of pruritus were not affected by cirrhosis, hepatic decompensation, or inflammatory bowel disease.

CONCLUSION

Itch is common in patients with PSC and is often associated with multiple prescriptions of antipruritic agents. Effective treatments for pruritus in patients with PSC remain an unmet need.

Clinical management of autoimmune liver diseases: juncture, opportunities, and challenges ahead

The three major autoimmune liver diseases are autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), and primary sclerosing cholangitis (PSC).These conditions are assumed to result from a breakdown in immunological tolerance, which leads to an inflammatory process that causes liver damage.The self-attack is started by T-helper cell-mediated identification of liver autoantigens and B-cell production of autoantibodies,and it is maintained by a reduction in the number and activity of regulatory T-cells.Infections and environmental factors have been explored as triggering factors for these conditions, in addition to a genetic predisposition.Allelic mutations in the HLA locus have been linked to vulnerability, as have relationships with single nucleotide polymorphisms in non-HLA genes.Despite the advances in the management of these diseases, there is no curative treatment for these disorders, and a significant number of patients eventually progress to an end-stage liver disease requiring liver transplantation.In this line, tailored immune-therapeutics have emerged as possible treatments to control the disease.In addition, early diagnosis and treatment are pivotal for reducing the long-lasting effects of these conditions and their burden on quality of life.Herein we present a review of the etiology, clinical presentation, diagnosis, and challenges on ALDs and the feasible solutions for these complex diseases.

DNA repair and disease: insights from the human DNA glycosylase NEIL family

The base excision repair pathway protects DNA from base damage via oxidation, deamination, alkylation and methylation. DNA glycosylases are key enzymes that recognize damaged bases in a lesion-specific manner and initiate the base excision repair process. Among these, the endonuclease VIII-like 1-3 (NEIL1-3) family, which is found in mammalian genomes, is a homolog of bacterial DNA glycosylases known as Fpg/Nei. NEIL enzymes have similar structures and substrates but with slight differences. When repair proteins are impaired, the accumulation of damaged bases can lead to increased genomic instability, which is implicated in various pathologies, including cancer and neurodegeneration. Notably, mutations in these proteins also influence a range of other diseases and inflammation. This review focuses on the influence of the NEIL family on human health across different organ systems. Investigating the relationship between NEIL mutations and diseases can improve our understanding of how these enzymes affect the human body. This information is crucial for understanding the basic mechanisms of DNA repair and enabling the development of novel inhibitors or gene therapies that target only these enzymes. Understanding the role of the NEIL family provides insights into novel therapies and improves our ability to combat genetic diseases.

Autoimmune Biliary Diseases: A Review of Primary Biliary Cholangitis, Primary Sclerosing Cholangitis, Immunoglobulin G4-Related Sclerosing Cholangitis, and Autoimmune Hepatitis

Autoimmune and immune-mediated biliary diseases represent a small proportion of biliary disorders, but owing to their progressive nature, lead to end-stage liver disease, necessitating liver transplantation for definitive management.

Limited validity of Mayo endoscopic subscore in ulcerative colitis with concomitant primary sclerosing cholangitis

BACKGROUND

Ulcerative colitis (UC) with concomitant primary sclerosing cholangitis (PSC) represents a distinct disease entity (PSC-UC). Mayo endoscopic subscore (MES) is a standard tool for assessing disease activity in UC but its relevance in PSC-UC remains unclear.

AIM

To assess the accuracy of MES in UC and PSC-UC patients, we performed histological scoring using Nancy histological index (NHI).

METHODS

MES was assessed in 30 PSC-UC and 29 UC adult patients during endoscopy. NHI and inflammation were evaluated in biopsies from the cecum, rectum, and terminal ileum. In addition, perinuclear anti-neutrophil cytoplasmic antibodies, fecal calprotectin, body mass index, and other relevant clinical characteristics were collected.

RESULTS

The median MES and NHI were similar for UC patients (MES grade 2 and NHI grade 2 in the rectum) but were different for PSC-UC patients (MES grade 0 and NHI grade 2 in the cecum). There was a correlation between MES and NHI for UC patients (Spearman's r = 0.40, P = 0.029) but not for PSC-UC patients. Histopathological examination revealed persistent microscopic inflammation in 88% of PSC-UC patients with MES grade 0 (46% of all PSC-UC patients). Moreover, MES overestimated the severity of active inflammation in an additional 11% of PSC-UC patients.

CONCLUSION

MES insufficiently identifies microscopic inflammation in PSC-UC. This indicates that histological evaluation should become a routine procedure of the diagnostic and grading system in both PSC-UC and PSC.

Comparing animal well-being between bile duct ligation models

A prevailing animal model currently used to study severe human diseases like obstructive cholestasis, primary biliary or sclerosing cholangitis, biliary atresia, and acute liver injury is the common bile duct ligation (cBDL). Modifications of this model include ligation of the left hepatic bile duct (pBDL) or ligation of the left bile duct with the corresponding left hepatic artery (pBDL+pAL). Both modifications induce cholestasis only in the left liver lobe. After induction of total or partial cholestasis in mice, the well-being of these animals was evaluated by assessing burrowing behavior, body weight, and a distress score. To compare the pathological features of these animal models, plasma levels of liver enzymes, bile acids, bilirubin, and within the liver tissue, necrosis, fibrosis, inflammation, as well as expression of genes involved in the synthesis or transport of bile acids were assessed. The survival rate of the animals and their well-being was comparable between pBDL+pAL and pBDL. However, surgical intervention by pBDL+pAL caused confluent necrosis and collagen depositions at the edge of necrotic tissue, whereas pBDL caused focal necrosis and fibrosis in between portal areas. Interestingly, pBDL animals had a higher survival rate and their well-being was significantly improved compared to cBDL animals. On day 14 after cBDL liver aspartate, as well as alanine aminotransferase, alkaline phosphatase, glutamate dehydrogenase, bile acids, and bilirubin were significantly elevated, but only glutamate dehydrogenase activity was increased after pBDL. Thus, pBDL may be primarily used to evaluate local features such as inflammation and fibrosis or regulation of genes involved in bile acid synthesis or transport but does not allow to study all systemic features of cholestasis. The pBDL model also has the advantage that fewer mice are needed, because of its high survival rate, and that the well-being of the animals is improved compared to the cBDL animal model.

Distinct metabolomic and lipidomic profiles in serum samples of patients with primary sclerosing cholangitis

Intoduction

Identification of specific metabolome and lipidome profile of patients with primary sclerosing cholangitis (PSC) is crucial for diagnosis, targeted personalized therapy, and more accurate risk stratification.

Methods

Nuclear magnetic resonance (NMR) spectroscopy revealed an altered metabolome and lipidome of 33 patients with PSC [24 patients with inflammatory bowel disease (IBD) and 9 patients without IBD] compared with 40 age-, sex-, and body mass index (BMI)-matched healthy controls (HC) as well as 64 patients with IBD and other extraintestinal manifestations (EIM) but without PSC.

Results

In particular, higher concentrations of pyruvic acid and several lipoprotein subfractions were measured in PSC in comparison to HC. Of clinical relevance, a specific amino acid and lipid profile was determined in PSC compared with IBD and other EIM.

Discussion

These results have the potential to improve diagnosis by differentiating PSC patients from HC and those with IBD and EIM.

A protective effect of inflammatory bowel disease on the severity of sclerosing cholangitis

Background

Primary sclerosing cholangitis (PSC) is a chronic liver disease marked by inflammation of the bile ducts and results in the development of strictures and fibrosis. A robust clinical correlation exists between PSC and inflammatory bowel disease (IBD). At present, published data are controversial, and it is yet unclear whether IBD drives or attenuates PSC.

Methods

Mdr2-deficient mice or DDC-fed mice were used as experimental models for sclerosing cholangitis. Additionally, colitis was induced in mice with experimental sclerosing cholangitis, either through infection with Citrobacter rodentium or by feeding with DSS. Lastly, fibrosis levels were determined through FibroScan analysis in people with PSC and PSC-IBD.

Results

Using two distinct experimental models of colitis and two models of sclerosing cholangitis, we found that colitis does not aggravate liver pathology, but rather reduces liver inflammation and liver fibrosis. Likewise, people with PSC-IBD have decreased liver fibrosis compared to those with PSC alone.

Conclusions

We found evidence that intestinal inflammation attenuates liver pathology. This study serves as a basis for further research on the pathogenesis of PSC and PSC-IBD, as well as the molecular mechanism responsible for the protective effect of IBD on PSC development. This study could lead to the discovery of novel therapeutic targets for PSC.

Phenotypes of Primary Sclerosing Cholangitis and Differential Diagnosis

Primary sclerosing cholangitis is a heterogenous immune-mediated disorder characterized by chronic inflammation and stricturing of the bile ducts. Though the driving pathophysiologic mechanisms remain elusive, there are several observed clinical phenotypes of the disease. The distribution of bile duct involvement, presence of concomitant inflammatory bowel disease, significant infiltration of IgG4-positive plasma cells, and overlapping features with other autoimmune disease has significant implications for prognosis and treatment. As there remains no pathognomonic finding for primary sclerosing cholangitis, a broad differential diagnosis and extensive evaluation of other underlying causes is critical to appropriate management.

Isocaloric diets with varying protein levels affected energy metabolism in young adult Sprague-Dawley rats via modifying the gut microbes: A lipid imbalance was brought on by a diet with a particularly high protein content

Protein is the most important macro-nutrient when it comes to maximizing health, body composition, muscle growth, and recovery of body tissue. In recent years, it has been found that protein also plays an important role in metabolism and gut microbiota. This study was performed to investigate the effects of an isocaloric diet with different crude protein contents on the energy metabolism of Sprague-Dawley (SD) rats. Results revealed that compared with the 20% crude protein (CP; control) diet, the 38% CP diet improved serum parameters that are associated with dyslipidemia and glucose metabolic disorders in SD rats, whereas the 50% CP diet increased liver injury indicators and fatty acid synthesis-related genes and protein expression in the liver. Compared with the control diet, the 14% CP diet increased the abundance of colonic short-chain fatty acid-producing bacteria (Lachnospiraceae_NK4A136_group and Ruminiclostridium_9) and promoted colonic microbial cysteine and methionine metabolism, the 38% CP diet up-regulated colonic microbial lysine biosynthesis and degradation pathways, and the 50% CP diet down-regulated colonic mucosal cholesterol metabolism. Furthermore, the increase of multiple colonic enteropathogenic bacteria in the 50% CP group was associated with higher palmitic acid and stearic acid concentrations in the colonic microbes and lower cholesterol and arachidonic acid concentrations in the colonic mucosa. These findings revealed that the 14% CP and 38% CP diets improved rats' energy metabolism, while the 50% CP diet was accompanied by lipid metabolism imbalances and an increase in the abundance of multiple enteropathogenic bacteria.

Causal effects from inflammatory bowel disease on liver function and disease: a two-sample Mendelian randomization study

Background

Accumulating evidence has shown that patients with inflammatory bowel disease (IBD) have liver function abnormalities and are susceptible to liver diseases. However, the existence of a causal relationship between IBD and liver function or disease remains unclear.

Methods

A two-sample Mendelian randomization (MR) analysis was performed using genetic associations from publicly available genome-wide association studies (GWAS). These associations encompass ulcerative colitis (UC), Crohn's disease (CD), liver function traits, and liver disease phenotypes. The liver function traits comprised hepatic biochemistries, percent liver fat, and liver iron content from the UK Biobank. Furthermore, the liver disease phenotypes included cholelithiasis, non-alcoholic fatty liver disease (NAFLD), primary sclerosing cholangitis (PSC), and primary biliary cholangitis (PBC) in cohorts of European ancestry. The primary estimation used the inverse-variance weighted method, with GWAS of C-reactive protein (CRP) in the UK Biobank serving as a positive control outcome.

Results

Genetically predicted UC is causally associated with decreased levels of albumin (ALB) and liver iron content, while genetically predicted CD is causally associated with increased levels of alkaline phosphatase (ALP). Moreover, genetically predicted UC or CD increases the risk of PSC, and CD increases the risk of PBC. Neither UC nor CD causally increases the risk of cholelithiasis and NAFLD.

Conclusion

UC affects the levels of ALB and liver iron content, while CD affects the levels of ALP. Both UC and CD increase the risk of PSC, and CD increases the risk of PBC.

Primary Sclerosing Cholangitis: Diagnostic Criteria

Primary sclerosing cholangitis is a chronic cholestatic liver disease characterized by inflammation and fibrosis of intra- and/or extrahepatic bile ducts leading to the formation of multifocal strictures alternated to bile duct dilatations. The diagnosis of the most common subtype of the disease, the large duct PSC, is based on the presence of elevation of cholestatic indices, the association of typical cholangiographic findings assessed by magnetic resonance cholangiography and the exclusion of causes of secondary sclerosing cholangitis. Liver biopsy is not routinely applied for the diagnosis of large duct PSC but is mandatory in the case of suspicion of small duct PSC or overlap with autoimmune hepatitis.

Liver Transplantation for Primary Sclerosing Cholangitis (PSC) With or Without Inflammatory Bowel Disease (IBD)-A European Society of Organ Transplantation (ESOT) Consensus Statement

Primary sclerosing cholangitis (PSC) is the classical hepatobiliary manifestation of inflammatory bowel disease (IBD) and a lead indication for liver transplantation (LT) in the western world. In this article, we present a Consensus Statement on LT practice, developed by a dedicated Guidelines' Taskforce of the European Society of Organ Transplantation (ESOT). The overarching goal is to provide practical guidance on commonly debated topics, including indications and timing of LT, management of bile duct stenosis in patients on the transplant waiting list, technical aspects of transplantation, immunosuppressive strategies post-transplant, timing and extension of intestinal resection and futility criteria for re-transplantation.

Primary sclerosing cholangitis-A long night's journey into day

Content available: Audio Recording.

Gene Set Enrichment Analysis Detected Immune Cell-Related Pathways Associated with Primary Sclerosing Cholangitis

Aim

To explore various immune cell-related causal pathways for primary sclerosing cholangitis (PSC).

Methods

Immune cell-related pathway association study was conducted via integrative analysis of PSC GWAS summary and five immune cell-related eQTL datasets. The GWAS summary data of PSC was driven from 4,796 PSC cases and 19,955 healthy controls. The eQTL datasets of CD4+ T cells, CD8+ T cells, B cells, natural killer cells (NK), monocytes, and peripheral blood cells (PB) were collected from recently eQTL study. The PSC GWAS summary dataset was first aligned with eQTL datasets of six blood cells to obtain the GWAS summary data at overlapped eQTL loci, separately. For each type of cell, the obtained PSC GWAS summary dataset of eQTLs was subjected to pathway enrichment analysis. 853 biological pathways from Kyoto Encyclopedia of Genes and Genomes, BioCarta, and Reactome pathway databases were analyzed.

Results

We identified 36 pathways for B cells, 33 pathways for CD4+ T cells, 28 pathways for CD8+ T cells, 33 pathways for monocytes (MN), 35 pathways for NK cells, and 33 for PB cells (all empirical P values <5.0 × 10-5). Comparing the pathway analysis results detected 25 pathways shared by five immune cells, such as KEGG_CELL_ADHESION_MOLECULES_CAMS (P value <5.0 × 10-5) and REACTOME_MHC_CLASS_II_ANTIGEN_ PRESENTATION (P value <5.0 × 10-5). Several cell-specific pathways were also identified, including BIOCARTA_INFLAM_PATHWAY (P value <5 × 10-5) for B cell.

Conclusion

Our study holds potential to identify novel candidate causal pathways and provides clues for revealing the complex genetic mechanism of PSC.

Three-months duration of fully-covered metal stent for refractory dominant extra-hepatic biliary stricture among primary sclerosing cholangitis patients: efficacy and safety

BACKGROUND

Dominant stricture (DS) is a main cause of complication among patients with Primary Sclerosing Cholangitis (PSC). Endoscopic treatment options include dilation and plastic stenting, each with its own benefits and drawbacks.

AIMS

The aim of the current study is to assess the safety and efficacy of fully-covered metal stent (FCMS) in these patients.

METHODS

A retrospective study of PSC patients with refractory DS, defined as strictures resistance to conventional therapy (balloon dilatation, plastic biliary stent insertion or both) and who underwent FCMS insertion for 3 months were included. The primary outcome was defined as clinical and laboratory improvement, while secondary outcomes were DS resolution upon stent removal and cholangiographic DS recurrence at 12-months after FCMS extraction.

RESULTS

Twenty patients were enrolled from January 2016 through January 2020. Improvement in weakness and pruritus were seen in 80% and 35%, 75% and 65%, 75% and 35% of patients at 1-3 and 6 months following FCMS removal, respectively. Similarly, consistent improvement in all liver enzymes and total bilirubin were seen in up to 6 month following stent removal. Only one patient (5%) needed premature FCMS removal due to cholangitis 1 week after stent placement and 2 cases (10%) of stent related pancreatitis were encountered. At 3-months all remaining stents were softly removed. Cholangiographic DS resolution was demonstrated in 13 patients (65%) after stent removal at 3-months, and DS recurred in 4 patients (4/13 = 30.7%) at 12-months following stent removal. Notably, only proximal biliary DS location showed a trend for DS recurrence (OR 28.6, P = 0.06).

CONCLUSION

Temporary 3 months duration FCMS was feasible, safe and effective treatment option among patients with PSC related refractory DS.

Cholestatic Liver Disease and Pregnancy: A Systematic Review and Meta-Analysis

Primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) are two types of chronic cholestatic liver disease (CCLD). Little is known regarding the relationship between these conditions and pregnancy. We performed a systematic review and meta-analysis regarding the maternal and fetal outcomes amongst patients with a known diagnosis of PBC and PSC undergoing pregnancy. Our analysis shows that patients with PBC and PSC who undergo pregnancy are at an increased risk of pre-term delivery, as well as the development of new or worsening pruritus during pregnancy. Additionally, patients with PBC are at higher risk of undergoing a biochemical disease flare during the postpartum period compared to during pregnancy. However, there were no documented cases of maternal mortality or development of decompensated cirrhosis during pregnancy or the postpartum period.

Review of incidence and outcomes of treatment of cholangiocarcinoma in patients with primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a premalignant condition and a well-documented risk factor for cholangiocarcinoma (CCA) which is the most common malignancy in this setting and the leading cause of deaths in the recent years, with an increasing incidence. PSC-associated CCA has a geographical distribution that follows the incidence of PSC, with an observed ascending gradient from the Eastern to the Western and from the Southern to the Northern countries. It may arise at any location along the biliary tree but is most common in the perihilar area. Patients with PSC and intrahepatic or perihilar CCA are typically not suitable for liver resection, which is otherwise the treatment of choice with curative intent in patients with resectable tumours, providing a radical resection with clear margins can be achieved. This largely relates to the commonly advanced stage of liver disease at presentation, which allows consideration for liver resection only for a very limited number of suitable patients with PSC. On the other hand, remarkable progress has been reached in the last decades with the implementation of a protocol combining neoadjuvant chemoradiation and orthotopic liver transplantation (OLT) for the treatment of perihilar CCA, within specific criteria. Excellent results have been achieved particularly for PSC patients with this cancer, who seem to benefit the most from this treatment, having converted this into an accepted indication for transplantation and the standard of care in several experienced centres. Intrahepatic CCA as an indication for OLT remains controversial and has not been accepted given disappointing previous results. However, as recent studies have shown favourable outcomes in early intrahepatic CCA, it may be that under defined criteria, OLT may play a more prominent role in the future. Distal CCA in the context of PSC requires aggressive surgical treatment with curative intent, when feasible. This review provides insight about particular features of CCA in the setting of PSC, with a main focus on its incidence, considerations relating to its anatomical location and implications to treatment and outcomes, through the viewpoint of historical evolution of management, and future perspectives.

Modulation of the Mucosa-Associated Microbiome Linked to the PTPN2 Risk Gene in Patients with Primary Sclerosing Cholangitis and Ulcerative Colitis

Gut microbiota appears to be involved in the pathogenesis of primary sclerosing cholangitis (PSC). The protein tyrosine phosphatase nonreceptor 2 (PTPN2) gene risk variant rs1893217 is associated with gut dysbiosis in inflammatory bowel disease (IBD), and PTPN2 was mentioned as a possible risk gene for PSC. This study assessed the microbial profile of ulcerative colitis (UC) patients with PSC and without PSC (non-PSC). Additionally, effects of the PTPN2 risk variant were assessed. In total, 216 mucosal samples from ileum, colon, and rectum were collected from 7 PSC and 42 non-PSC patients, as well as 28 control subjects (non-IBD). The microbial composition was derived from 16S rRNA sequencing data. Overall, bacterial richness was highest in PSC patients, who also had a higher relative abundance of the genus Roseburia compared to non-PSC, as well as Haemophilus, Fusobacterium, Bifidobacterium, and Actinobacillus compared to non-IBD, as well as a lower relative abundance of Bacteroides compared to non-PSC and non-IBD, respectively. After exclusion of patients with the PTPN2 risk variant, Brachyspira was higher in PSC compared to non-PSC, while, solely in colon samples, Eubacterium and Tepidimonas were higher in PSC vs. non-IBD. In conclusion, this study underlines the presence of gut mucosa-associated microbiome changes in PSC patients and rather weakens the role of PTPN2 as a PSC risk gene.

Recurrent Primary Sclerosing Cholangitis: Current Understanding, Management, and Future Directions

Patients with primary sclerosing cholangitis (PSC) constitute 5 to 15% of patients listed for liver transplantation worldwide. Although post-transplant outcomes are favorable, recurrent PSC (rPSC) occurs in an important subset of patients, with higher prevalence rates reported with increasing time from transplant. Given its association with poor graft outcomes and risk of retransplant, effort has been made to understand rPSC, its pathophysiology, and risk factors. This review covers these facets of rPSC and focuses on implicated risk factors including pretransplant recipient characteristics, inflammatory bowel-disease-related factors, and donor-specific and transplant-specific factors. Confirming a diagnosis of rPSC requires thoughtful consideration of alternative etiologies so as to ensure confidence in diagnosis, management, subsequent risk assessment, and counseling for patients. Unfortunately, no cure exists for rPSC; however, future large-scale efforts are underway to better characterize the natural history of rPSC and its associated risk factors with hopes of identifying potential key targets for novel therapies.

Inflammatory bowel disease course in liver transplant versus non-liver transplant patients for primary sclerosing cholangitis: LIVIBD, an IG-IBD study

BACKGROUND

Data regarding the effect of orthotopic liver transplantation (OLT) for primary sclerosing cholangitis (PSC) on inflammatory bowel disease (IBD) course are scarce and conflicting.

AIMS

To compare the incidence of refractory IBD in two groups (OLT and non-OLT) of patients affected by IBD and PSC.

METHODS

An observational, multicentre, cohort retrospective study was conducted by the Italian Group for the study of IBD in Italy. The primary outcome was the need for biologic therapy or bowel resection for medically refractory IBD or hospitalization due to IBD relapse during the follow-up. Secondary outcomes were rate of colonic dysplasia, colorectal cancer, other solid tumours, lymphoma.

RESULTS

Eighty-four patients were included in the study. The primary outcome was not different between OLT and non-OLT groups (11/27, 40.7%, versus 20/57, 35.1%, respectively, p = 0.62). The lymphoma and other tumours (thyroid cancer, kidney cancer, ileal tumour, ovarian cancer, cervical cancer) rates were significantly higher in the OLT group (p = 0.04 and p = 0.005, respectively), at the limit of statistical significance for high-grade colonic dysplasia (p = 0.06).

CONCLUSION

OLT in patients affected by IBD and PSC is not a risk factor for a more severe IBD course, but it is associated with a higher occurrence of cancer.

Clinical Characterization of Ulcerative Colitis in Patients with Primary Sclerosing Cholangitis

Objectives

The clinical/colonoscopic features of ulcerative colitis (UC) associated with primary sclerosing cholangitis (PSC), the prognostic impact of UC, and the utility of UC screening in PSC patients are unknown. We characterized UC associated with PSC and assessed UC's impact on the prognosis of PSC and the importance of colonoscopic UC screening in PSC patients.

Methods

We retrospectively analyzed the cases of 77 patients treated for PSC at a single center (April 2000–July 2019). We reviewed the clinical/colonoscopic profiles of the concurrent UC patients and compared the clinical profiles, survival, and primary causes of death between the patients with/without UC (n = 35/n = 42). The details of all patients' colonoscopies were reviewed.

Results

The concurrent UC group: 17 men, 18 women, diagnosed with PSC at the mean (SD) age of 36 (17) years; 21 patients (60%) had no UC symptoms. Colonoscopy revealed pancolitis in all patients, predominantly affecting the right-sided colon in 30 patients (86%). Lesions were scattered. Backwash ileitis (n = 13, 37%) and rectal sparing (n = 18, 51%) were observed. Most patients had mild UC; some had moderate or more severe UC (median Ulcerative Colitis Endoscopic Index of Severity (UCEIS) score 2; range, 1–5). Ludwig's stage determined by liver biopsy did not correlate with the Mayo endoscopic score for UC. The patients with UC were diagnosed with PSC at a significantly younger age than those without UC (mean (SD), 36 [17] years vs. 55 [19] years, p < 0.0001) and had a significantly higher 5-year survival rate (97.1% vs. 70.5%, p = 0.0028). UC was detected in 19 of 34 asymptomatic patients (56%) who underwent colonoscopy screening.

Conclusions

Our cohort's clinical/colonoscopic features of UC associated with PSC are more moderate or severe UC than previous cases. The coexistence of UC might affect the prognosis of PSC. In this regard, colonoscopy in PSC patients is an important examination for determining prognosis. There is also asymptomatic UC in patients with PSC. In this regard, screening for colonoscopy in PSC patients is essential. When a diagnosis of PSC is made, immediate colonoscopy is a priority with UC complications in mind.

Cholestatic Liver Diseases: A Primer for Generalists and Subspecialists

Cholestasis describes impairment in bile formation or flow which can manifest clinically with fatigue, pruritus, and jaundice. The differential diagnosis of cholestatic liver diseases is broad, and the etiologies of cholestasis vary in the anatomical location of the defect and acuity of presentation. Cholestasis may occur in a variety of clinical scenarios. Therefore, it is important for a diverse audience with varied clinical practices to have a basic understanding of manifestations of cholestatic liver diseases.

Recurrence of primary sclerosing cholangitis after liver transplantation is associated with specific changes in the gut microbiome pretransplant - a pilot study

Primary sclerosing cholangitis (PSC) is a common indication for liver transplantation (LT). Up to 25% of patients experience recurrence of PSC (rPSC) after LT, which is associated with significant morbidity and mortality. To date, it is not possible to predict which patients are at risk for rPSC. The aetiology of PSC is complex and is speculated to involve translocation of intestinal bacteria to the liver, because of its frequent co‐occurrence with inflammatory bowel diseases (IBD). Here, we investigate whether the mucosal intestinal microbiome of PSC patients (n = 97) at time of first LT can identify those patients who will develop rPSC. 16S gene sequencing of bacterial DNA isolated from formalin‐fixed paraffin‐embedded biopsies showed that PSC patients with Crohn’s disease (n = 15) have a reduced microbial diversity and that inflammation of the mucosa is associated with beta‐diversity changes and feature differences. No differences in alpha‐ or beta diversity were observed between patients with rPSC (n = 14) and without rPSC (n = 83). However, many over‐represented bacterial features were detected in patients with rPSC, while surprisingly, those without recurrence of disease were characterized by an increased presence of the Gammaproteobacteria Shigella. This pilot study warrants further investigation into bacterial differences between rPSC and non‐rPSC patients.

Evaluation of two functional CD24 polymorphisms in primary sclerosing cholangitis

Background: Primary sclerosing cholangitis (PSC) is a progressive liver disease and characterized by chronic inflammation, sclerosis and strictures of bile ducts. Several genetic risk factors might contribute to pathogenesis. Functional single nucleotide polymorphisms (SNPs) in the CD24 gene have been associated with the development of autoimmune and autoinflammatory diseases and might contribute to the susceptibility for inflammatory bowel disease (IBD).Aim: This retrospective study aimed to evaluate the impact of two functional CD24 SNPs on clinical features and disease progression in patients with PSC.Methods: A C to T coding polymorphism (rs8734) and a TG deletion in the 3´- untranslated region (rs3838646) were genotyped. The study cohort comprises of 359 PSC patients for rs3838646 genotype and 335 PSC patients for rs8734 genotype. Clinical and laboratory parameters were collected by chart review.Results: For the rs8734 genotype, 175 patients (52.2%) were found to be homozygous wildtype ('Ala/Ala'), 127 (37.9%) patients were heterozygous ('Ala/Val') and 33 patients (9.9%) were homozygous mutant ('Val/Val'). The rs8734genotype was associated with a decreased risk for dominant strictures at first diagnosis of PSC (p = .04). For the rs3838646 genotype, 322 patients (89.7%) were found to be homozygous wildtype ('TG/TG'); 37 showed the 'TG/del' genotype (10.3%). The 'TG/del'genotype was associated with alower risk of IBD (p = .01).There was no influence of both CD24 SNPs with clinical end points or transplantation-free survival in our PSC cohort.Conclusion: Our results suggest a mild association of the rs8734 CD24 genotype with dominant strictures at first diagnosis of PSC. The rs3838646 CD24 genotype is associated with a lower rate of IBD. Both SNPs seem to modulate the clinical phenotype without major pathogenetic importance for disease progression in PSC.

Consensus guidelines: best practices for detection, assessment and management of suspected acute drug-induced liver injury occurring during clinical trials in adults with chronic cholestatic liver disease

BACKGROUND

Improved knowledge of the molecular pathophysiology and immunopathogenesis of cholestatic liver diseases in recent years has led to an increased interest in developing novel therapies. Patients with cholestatic liver disease often require different approaches to assessment and management of suspected drug-induced liver injury (DILI) compared to those with healthy livers and those with parenchymal liver diseases. At present, there are no regulatory guidelines or society position papers, that systematically address best practices pertaining to detection of DILI in these patients.

AIMS

To outline best practices for detection, assessment and management of suspected acute DILI during clinical trials in adults with the cholestatic liver diseases - Primary Biliary Cholangitis (PBC) and Primary Sclerosing Cholangitis (PSC).

METHODS

This is one of the several papers developed by the IQ DILI Initiative, which is comprised of members from 16 pharmaceutical companies, in collaboration with DILI experts from academia and regulatory agencies. The contents are the result of an extensive literature review, as well as in-depth discussions among industry, regulatory and academic DILI experts, to achieve consensus recommendations on DILI-related issues occurring during clinical trials for cholestatic liver diseases.

RESULTS

Recommended best practices are outlined pertaining to hepatic eligibility criteria, monitoring of liver tests, approach to a suspected DILI signal, and hepatic discontinuation rules.

CONCLUSIONS

This paper provides a framework for the approach to detection, assessment and management of suspected acute DILI occurring during clinical trials in adults with cholestatic liver disease.

Inflammatory Bowel Disease in Children with Elevated Serum Gamma Glutamyltransferase Levels

OBJECTIVE

To assess the characteristics of inflammatory bowel disease and disease prognosis among children with elevated gamma glutamyltransferase (GGT) and primary sclerosing cholangitis (PSC)-ulcerative colitis (UC).

STUDY DESIGN

Our longitudinal, population-based cohort comprised all children and young adults diagnosed with UC in the Canadian province of Manitoba between 2011 and 2018. Diagnosis of PSC was confirmed based on a combination of cholestatic biochemical markers and cholangiographic features. The Fisher exact test with Bonferroni correction was used to examine the relationship between categorical variables.

RESULTS

We enrolled 95 children with UC/Inflammatory bowel disease-unclassified with a median age at diagnosis of 14 years (IQR: 10.4-15.9 years) and 1399 person-years follow-up. Among them, 9 children developed PSC-UC, with an incidence rate of 6.43 new cases per 1000 person-years. In this cohort, 8 (72.7%) of 11 children with high baseline serum GGT levels developed PSC-UC in comparison with 1 (1.2%) of 84 children with normal serum GGT levels at baseline (P < .001). All children with high serum GGT levels at diagnosis had pancolitis in comparison with 63.9% of children with normal serum GGT levels (P = .01). Children with high serum GGT levels were more likely to be perinuclear neutrophil antibodies-positive than those with normal levels (90.9% vs 52.0%, P = .01).

CONCLUSIONS

Our findings indicated that pediatric patients with UC and with even mild elevations of serum GGT levels, especially at baseline, might be predisposed to develop PSC.

Validation, clinical utility and limitations of the Amsterdam-Oxford model for primary sclerosing cholangitis

BACKGROUND & AIMS

Recently the Amsterdam-Oxford model (AOM) was introduced as a prognostic model to assess the risk of death and/or liver transplantation (LT) in primary sclerosing cholangitis (PSC). We aimed to validate and assess the utility of the AOM.

METHODS

Clinical and laboratory data were collected from the time of PSC diagnosis until the last visit or time of LT or death. The AOM was calculated at yearly intervals following PSC diagnosis. Discriminatory performance was assessed by calculation of the C-statistic and prediction accuracy by comparing the predicted survival with the observed survival in Kaplan-Meier estimates. A grid search was performed to identify the most discriminatory AOM threshold.

RESULTS

A total of 534 patients with PSC and a mean (SD) age of 39.2 (13.1) years were included. The diagnosis was large duct PSC in 466 (87%), PSC with features of autoimmune hepatitis in 52 (10%) and small-duct PSC in 16 (3%). During the median (IQR) follow-up of 7.8 (4.0-12.6) years, 167 patients underwent LT and 65 died. The median LT-free survival was 13.2 (11.8-14.7) years. The C-statistic of the AOM ranged from 0.67 at baseline to 0.75 at 5 years of follow-up. The difference between the predicted and observed survival ranged from -1.6% at 1 year to + 3.9% at 5 years of follow-up. Patients that developed AOM scores >2.0 were at significant risk of LT or death (time-dependent hazard ratio 4.09; 95% CI 2.99-5.61).

CONCLUSIONS

In this large cohort of patients with PSC, the AOM showed an adequate discriminative performance and good prediction accuracy at PSC diagnosis and during follow-up. This study further validates the AOM as a valuable risk stratification tool in PSC and extends its utility.

LAY SUMMARY

In our study we assessed whether the Amsterdam-Oxford model (AOM) is able to correctly estimate the risk of liver transplantation or death in patients with primary sclerosing cholangitis (PSC). This model uses 7 objective and readily available variables to estimate prognosis for individual patients at the time of PSC diagnosis. The AOM may aid in patient counselling and timing of diagnostic procedures or therapeutic interventions for complications of liver disease. We confirm that the model works well at PSC diagnosis, but also when the AOM is recalculated at different timepoints during follow-up, greatly improving the applicability of the model in clinical practice and for individual patients.

British Society of Gastroenterology and UK-PSC guidelines for the diagnosis and management of primary sclerosing cholangitis

These guidelines on the management of primary sclerosing cholangitis (PSC) were commissioned by the British Society of Gastroenterology liver section. The guideline writing committee included medical representatives from hepatology and gastroenterology groups as well as patient representatives from PSC Support. The guidelines aim to support general physicians, gastroenterologists and surgeons in managing adults with PSC or those presenting with similar cholangiopathies which may mimic PSC, such as IgG4 sclerosing cholangitis. It also acts as a reference for patients with PSC to help them understand their own management. Quality of evidence is presented using the AGREE II format. Guidance is meant to be used as a reference rather than for rigid protocol-based care as we understand that management of patients often requires individual patient-centred considerations.

Rheumatologie und Hepatologie: Diagnostik und Therapie von autoimmunen Lebererkrankungen

Unter autoimmunen Lebererkrankungen werden im klassischen Sinne 3 verschiedene Entitäten, die Autoimmune Hepatitis (AIH), die Primär biliäre Cholangitis (PBC) und die Primär sklerosierende Cholangitis (PSC) verstanden. Der nachfolgende Übersichtartikel fokusiert auf die Diagnostik und die Therapie dieser 3 autoimmunen Lebererkrankungen und gibt eine Übersicht zu möglichen zusätzlich assoziierten Autoimmunerkrankungen.

Primary Sclerosing Cholangitis: A Concise Review of Diagnosis and Management

Primary sclerosing cholangitis is a rare, chronic cholestatic liver disease characterized by progressive idiopathic stricturing of the biliary system, typically leading to cirrhosis, end-stage liver disease, and colonic or hepatobiliary malignancy. Its presentation is often that of asymptomatic alkaline phosphatase elevation. When symptoms are present, they typically include fatigue, pruritus, or jaundice. The diagnosis can be confirmed via cholangiography, either magnetic resonance cholangiography (MRCP) or endoscopic retrograde cholangiography if the former is inconclusive. The clinical course is marked by progressive liver disease leading to cirrhosis with its attendant complications of portal hypertension, often including recurrent episodes of cholangitis. Greater elevation in alkaline phosphatase or liver stiffness is associated with worse clinical outcomes. Management includes endoscopic treatment of symptomatic biliary strictures and evaluation of dominant strictures as no adequate medical treatment is available. Multiple medical therapies are under evaluation. Ultimately, liver transplantation may be necessary for management of decompensated cirrhosis or disabling symptoms. There is also a markedly increased risk of cancer, notably including cholangiocarcinoma and gallbladder and colorectal cancers (particularly in patients with colitis). Cancer screening can be done with semi-annual liver imaging (MRCP or ultrasound) and colonoscopy every 1-2 years in those with colitis.

Evolving role of magnetic resonance techniques in primary sclerosing cholangitis

Development of non-invasive methods to risk-stratify patients and predict clinical endpoints have been identified as one of the key research priorities in primary sclerosing cholangitis (PSC). In addition to serum and histological biomarkers, there has been much recent interest in developing imaging biomarkers that can predict disease course and clinical outcomes in PSC. Magnetic resonance imaging/magnetic resonance cholangiopancreatography (MRI/MRCP) continue to play a central role in the diagnosis and follow-up of PSC patients. Magnetic resonance (MR) techniques have undergone significant advancement over the last three decades both in MR data acquisition and interpretation. The progression from a qualitative to quantitative approach in MR acquisition techniques and data interpretation, offers the opportunity for the development of objective and reproducible imaging biomarkers that can potentially be incorporated as an additional endpoint in clinical trials. This review article will discuss how the role of MR techniques have evolved over the last three decades from emerging as an alternative diagnostic tool to endoscopic retrograde cholangiopancreatography, to being instrumental in the ongoing search for imaging biomarker of disease stage, progression and prognosis in PSC.

Risk of recurrence of primary sclerosing cholangitis after liver transplantation is associated with de novo inflammatory bowel disease

AIM

To evaluate risk factors for primary sclerosing cholangitis (PSC) recurrence (rPSC) after orthotopic liver transplantation (OLT) in patients with well-preserved colons.

METHODS

We retrospectively evaluated the medical records of all patients transplanted for PSC in our center between July 1994 and May 2015 and selected 47 with follow-up of at least 60 mo for further analysis based on strict inclusion and exclusion criteria. rPSC was confirmed by magnetic resonance or endoscopic retrograde cholangiopancreatography and liver biopsy. All patients were evaluated by protocolary pre-OLT colonoscopy with randomized mucosal biopsies. Colonoscopy was repeated annually after OLT. Both organ donors and recipients were human leukocyte antigen (HLA) typed by serological and/or DNA methods. All input data were thoroughly analyzed employing relevant statistical methods.

RESULTS

Altogether, 31 men and 16 women with a median (range) age of 36 (15-68) years at the time of OLT and a median follow-up of 122 (60-249) mo were included. rPSC was confirmed in 21/47 (44.7%) of patients, a median 63 (12-180) mo after transplantation. De novo colitis [rPSC in 11/12, P ≤ 0.05, hazard ratio (HR): 4.02, 95% confidence interval (CI): 1.58-10.98] and history of acute cellular rejection (rPSC in 14/25, P ≤ 0.05; HR: 2.66, 95%CI: 1.03-7.86) showed strong positive associations with rPSC. According to the univariate analysis, overlapping features of autoimmune hepatitis (rPSC in 5/5, P ≤ 0.05) and HLA-DRB1*07 in the donor (rPSC in 10/15, P ≤ 0.05) represent other potential risk factors for rPSC, while the HLA-DRB1*04 (rPSC in 0/6, P ≤ 0.05), HLA-DQB1*03 (rPSC in 1/11, P ≤ 0.05), and HLA-DQB1*07 (rPSC in 0/7, P ≤ 0.05) recipient alleles may have protective roles.

CONCLUSION

De novo colitis and acute cellular rejection are clinical conditions significantly predisposed towards recurrence of PSC after liver transplantation.

Colitis Promotes a Pathological Condition of the Liver in the Absence of Foxp3+ Regulatory T Cells

Inflammatory bowel disease is associated with extraintestinal diseases such as primary sclerosing cholangitis in the liver. Interestingly, it is known that an imbalance between Foxp3⁺ regulatory T cells (Treg) and Th17 cells is involved in inflammatory bowel disease and also in primary sclerosing cholangitis. To explain these associations, one hypothesis is that intestinal inflammation and barrier defects promote liver disease because of the influx of bacteria and inflammatory cells to the liver. However, whether and how this is linked to the Treg and Th17 cell imbalance is unclear. To address this, we used dextran sodium sulfate (DSS) and T cell transfer colitis mouse models. We analyzed the pathological conditions of the intestine and liver on histological, cellular, and molecular levels. We observed bacterial translocation and an influx of inflammatory cells, in particular Th17 cells, to the liver during colitis. In the DSS colitis model, in which Treg were concomitantly increased in the liver, we did not observe an overt pathological condition of the liver. In contrast, the T cell-mediated colitis model, in which Treg are not abundant, was associated with marked liver inflammation and a pathological condition. Of note, upon depletion of Treg in DEREG mice, DSS colitis promotes accumulation of Th17 cells and a pathological condition of the liver. Finally, we studied immune cell migration using KAEDE mice and found that some of these cells had migrated directly from the inflamed intestine into the liver. Overall, these data indicate that colitis can promote a pathological condition of the liver and highlight an important role of Treg in controlling colitis-associated liver inflammation.

Frequency, Risk Factors, and Outcome of Gallbladder Polyps in Patients With Primary Sclerosing Cholangitis: A Case-Control Study

The prevalence polyps (GBPs) in the general population has been estimated to be approximately 5%, with up to 10% of these being dysplastic or malignant. Previous studies have suggested that patients with primary sclerosing cholangitis (PSC) have increased frequency of GBPs. However, data on the prevalence, risk factors, and outcome of GBPs in these patients are sparse. This case‐control study investigates the frequency, risk factors, and outcome of GBPs in patients with PSC. In this study, 363 patients with an established diagnosis of PSC based on magnetic resonance cholangiopancreatography (MRCP), endoscopic retrograde cholangiopancreatography (ERCP), or liver biopsy were identified. Patients with at least one abdominal imaging and no history of cholecystectomy before the first available abdominal imaging were included. The presence of GBPs was confirmed by abdominal computed tomography (CT), magnetic resonance imaging (MRI), or ultrasound. Patients with GBPs were compared to those without GBPs. Furthermore, patients with malignant/premalignant polyps were compared to those with benign polyps. The frequency of GBPs in patients with PSC was 10.6%. There was no significant difference in the frequency of inflammatory bowel disease (IBD) between the two groups. Of the 16 with GBPs who underwent cholecystectomy, 10 had malignant/premalignant lesions, of whom 6 had adenocarcinoma, and 4 had high‐grade dysplasia. Of the 6 patients with adenocarcinoma, 4 had lesions >10 mm, 1 had a lesion as small as 4 mm, and 1 had a 7‐mm lesion. Conclusion: GBPs may be frequently seen in patients with PSC. These lesions seem to occur independent of IBD. In patients with PSC, even small GBPs appear to have a risk of malignancy. These findings suggest that patients with PSC and GBPs may benefit from cholecystectomy, regardless of the size of the polyp.

Dominant strictures in primary sclerosing cholangitis: A multicenter survey of clinical definitions and practices

Dominant strictures (DSs) of the biliary tree occur in approximately 50% of patients with primary sclerosing cholangitis (PSC) and may cause significant morbidity. Nevertheless, the definition and management of DSs lacks consensus. We aimed to better understand current perceptions and practices regarding PSC-associated DSs. We conducted an anonymous, 23-question, survey-based study wherein electronic surveys were distributed to 131 faculty in the Division of Gastroenterology and Hepatology at the three Mayo Clinic campuses (Rochester, Scottsdale, and Jacksonville) as well as the affiliated practice network. Responses were aggregated and compared, where applicable, to practice guidelines of the American Association for the Study of Liver Diseases and European Association for the Study of the Liver. A total of 54 faculty (41.2%) completed the survey, of whom 24 (44.4%) were hepatologists, 21 (38.9%) gastroenterologists, and 9 (16.7%) advanced endoscopists. One of the major study findings was that there was heterogeneity among participants' definition, evaluation, management, and follow-up of DSs in PSC. The majority of participant responses were in accordance with societal practice guidelines, although considerable variation was noted. Conclusion: Despite the prevalence and morbidity of DSs in PSC, clinical perceptions and practices vary widely among hepatologists, gastroenterologists, and advanced endoscopists who manage these patients, even within a single health care system. Further studies are needed to address these variations, develop general and evidence-based consensus, and increase adherence to societal guidelines. (Hepatology Communications 2018;2:836-844).

Risk factors and prognosis for recurrent primary sclerosing cholangitis after liver transplantation: a Nordic Multicentre Study

OBJECTIVES

The risk for recurrent primary sclerosing cholangitis (rPSC) after liver transplantation is associated with inflammatory bowel disease (IBD). We assessed the frequency of rPSC and studied risk factors for recurrent disease with special focus on IBD. We also evaluated the importance of rPSC for prognosis.

MATERIALS AND METHODS

All liver transplanted PSC patients in the Nordic countries between 1984 and 2007 (n = 440), identified by the Nordic Liver Transplant Registry, were studied. Data were retrieved from patients' chart reviews. Multivariable Cox regression models were used to calculate risk factors for rPSC and death.

RESULTS

Of the 440 patients with a follow-up time after liver transplantation of 3743 patient years, rPSC was diagnosed in 19% (n = 85). Colectomy before liver transplantation was associated with a reduced risk of rPSC (HR 0.49; 95% CI, 0.26-0.94, p = 0.033). Neither high IBD activity nor presence of IBD flares before or after liver transplantation was associated with rPSC. Treatment with tacrolimus was an independent risk factor associated with increased risk for rPSC (HR, 1.81; 95% CI, 1.15-2.86, p = 0.010). The risk of dying or needing a re-transplantation after rPSC was increased in all age groups, but highest in patients transplanted before 40 years of age (HR 7.3; 95% CI, 4.1-12.8, p = 0.0001).

CONCLUSIONS

This study confirms that colectomy before liver transplantation is associated with a decreased risk of rPSC. Inflammatory activity of IBD was not associated with the risk of rPSC. Tacrolimus was an independent risk factor for PSC recurrence and its use as first line immunosuppression in PSC needs further study.

Colectomy prior to diagnosis of primary sclerosing cholangitis is associated with improved prognosis in a nationwide cohort study of 2594 PSC-IBD patients

BACKGROUND

Despite the close relationship between primary sclerosing cholangitis (PSC) and inflammatory bowel disease (IBD), the association between colectomy and the prognosis of PSC remains controversial.

AIM

To explore whether colectomy prior to PSC-diagnosis is associated with transplant-free survival.

METHODS

A nationwide cohort study in Sweden including all patients aged 18 to 69 years in whom both PSC and IBD was diagnosed between 1987 and 2014 was undertaken. Each patient was followed from date of both PSC and IBD diagnoses until liver transplantation or death, or 31 December 2014. Patients with colon in situ, and colectomy prior to PSC-diagnosis were compared. Survival analyses were performed using the Kaplan-Meier method and multivariable Cox regression models.

RESULTS

Of the 2594 PSC-IBD patients, 205 patients were treated with colectomy before PSC-diagnosis. During follow-up, liver transplantations were performed in 327 patients and 509 died. The risk of liver transplantation or death was lower in patients treated with colectomy prior to PSC-diagnosis (HR 0.71, 95% CI 0.53-0.95) than in patients with colon in situ. Male gender, longer time between IBD and PSC-diagnosis and older age were all associated with an increased risk of liver transplantation or death. Colectomy after PSC-diagnosis was however not associated with an increased risk of liver transplantation or death during long-term follow-up.

CONCLUSIONS

In PSC-IBD patients, colectomy prior to PSC-diagnosis is associated with a decreased risk of liver transplantation or death.

Primary sclerosing cholangitis: A review and update

Primary sclerosing cholangitis (PSC) is a rare, chronic, cholestatic liver disease of uncertain etiology characterized biochemically by cholestasis and histologically and cholangiographically by fibro-obliterative inflammation of the bile ducts. In a clinically significant proportion of patients, PSC progresses to cirrhosis, end-stage liver disease, and/or hepatobiliary cancer, though the disease course can be highly variable. Despite clinical trials of numerous pharmacotherapies over several decades, safe and effective medical therapy remains to be established. Liver transplantation is an option for select patients with severe complications of PSC, and its outcomes are generally favorable. Periodic surveillance testing for pre- as well as post-transplant patients is a cornerstone of preventive care and health maintenance. Here we provide an overview of PSC including its epidemiology, etiopathogenesis, clinical features, associated disorders, surveillance, and emerging potential therapies.

Primary sclerosing cholangitis - a comprehensive review

Primary sclerosing cholangitis (PSC) is a rare disorder characterised by multi-focal bile duct strictures and progressive liver disease. Inflammatory bowel disease is usually present and there is a high risk of cholangiocarcinoma and colorectal cancer. Most patients ultimately require liver transplantation, after which disease recurrence may occur. With limited therapeutic options and a lack of proven surveillance strategies, patients currently have significant unmet needs. In the present seminar, we provide a comprehensive review of the status of the field. We emphasise developments related to patient stratification and disease behaviour, and provide an overview of management options from a practical, patient-centered perspective. We survey advances made in the understanding of PSC pathogenesis and summarise the ongoing efforts to develop an effective therapy based on these insights.

Pathological features of primary sclerosing cholangitis identified by bile proteomic analysis

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease of unknown origin. Previous bile proteomic analyses in patients with PSC have revealed changes in disease activity specific to malignant transformation. In this study, we established a reference bile duct-derived bile proteome for PSC that can be used to evaluate biliary pathophysiology. Samples were collected from patients with PSC or with choledocholithiasis (control) (n=6 each). Furthermore, patients with PSC-associated cholangiocarcinoma (CC) and with CC without concomitant PSC were analyzed. None of the patients showed signs of inflammation or infection based on clinical and laboratory examinations. Proteins overexpressed in patients with PSC relative to control patients were detected by two-dimensional difference gel electrophoresis and identified by liquid chromatography-tandem mass spectrometry. Functional proteomic analysis was performed using STRING software. A total of 101 proteins were overexpressed in the bile fluid of patients with PSC but not in those of controls; the majority of these were predicted to be intracellular and related to the ribosomal and proteasomal pathways. On the other hand, 91 proteins were found only in the bile fluid of controls; most were derived from the extracellular space and were linked to cell adhesion, the complement system, and the coagulation cascade. In addition, proteins associated with inflammation and the innate immune response-e.g., cluster of differentiation 14, annexin-2, and components of the complement system-were upregulated in PSC. The most prominent pathways in PSC/CC-patients were inflammation associated cytokine and chemokine pathways, whereas in CC-patients the Wnt signaling pathway was upregulated. In PSC/CC-patients DIGE-analysis revealed biliary CD14 and Annexin-4 expression, among others, as the most prominent protein that discriminates between both cohorts. Thus, the bile-duct bile proteome of patients with PSC shows disease-specific changes associated with inflammation and the innate immune response even in the absence of obvious clinical signs of cholangitis, malignancy, or inflammation. This article is part of a Special Issue entitled: Cholangiocytes in Health and Diseaseedited by Jesus Banales, Marco Marzioni and Peter Jansen.

HLA haplotypes in primary sclerosing cholangitis patients of admixed and non-European ancestry

Primary sclerosing cholangitis (PSC) is strongly associated with several human leukocyte antigen (HLA) haplotypes. Due to extensive linkage disequilibrium and multiple polymorphic candidate genes in the HLA complex, identifying the alleles responsible for these associations has proven difficult. We aimed to evaluate whether studying populations of admixed or non-European descent could help in defining the causative HLA alleles. When assessing haplotypes carrying HLA-DRB1*13:01 (hypothesized to specifically increase the susceptibility to chronic cholangitis), we observed that every haplotype in the Scandinavian PSC population carried HLA-DQB1*06:03. In contrast, only 65% of HLA-DRB1*13:01 haplotypes in an admixed/non-European PSC population carried this allele, suggesting that further assessments of the PSC-associated haplotype HLA-DRB1*13:01-DQA1*01:03-DQB1*06:03 in admixed or multi-ethnic populations could aid in identifying the causative allele.

Bile acids and intestinal microbiota in autoimmune cholestatic liver diseases

Autoimmune cholestatic liver diseases, including primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC), are manifested as an impairment of normal bile flow and excessive accumulation of potentially toxic bile acids. Endogenous bile acids are involved in the pathogenesis and progression of cholestasis. Consequently, chronic cholestasis affects the expression of bile acid transporters and nuclear receptors, and results in liver injury. Several lines of evidence suggest that intestinal microbiota plays an important role in the etiopathogenesis of cholestatic liver diseases by regulating metabolism and immune responses. However, progression of the disease may also affect the composition of gut microbiota, which in turn exacerbates the progression of cholestasis. In addition, the interaction between intestinal microbiota and bile acids is not unidirectional. Bile acids can shape the gut microbiota community, and in turn, intestinal microbes are able to alter bile acid pool. In general, gut microbiota actively communicates with bile acids, and together play an important role in the pathogenesis of PBC and PSC. Targeting the link between bile acids and intestinal microbiota offers exciting new perspectives for the treatment of those cholestatic liver diseases. This review highlights current understanding of the interactions between bile acids and intestinal microbiota and their roles in autoimmune cholestatic liver diseases. Further, we postulate a bile acids-intestinal microbiota-cholestasis triangle in the pathogenesis of autoimmune cholestatic liver diseases and potential therapeutic strategies by targeting this triangle.

Impact of age at diagnosis on disease progression in patients with primary sclerosing cholangitis

Background

The median age of diagnosis of primary sclerosing cholangitis (PSC) is ∼30-40 years.

Objective

We aimed to analyse disease progression and liver-dependent survival in patients diagnosed with PSC after 50 years of age.

Methods

Patients with PSC were analysed with regard to their age at diagnosis. Patients with a first diagnosis of PSC after the age of 50 years were considered as the late-onset group.

Results

A total of 32/215 (14.9%) patients were diagnosed with PSC after 50 years of age. The proportion of females was significantly higher among patients with late-onset PSC (48.4 vs. 27.3%; p = 0.02). Patients with later diagnosis required dilatation therapy more often due to dominant stenosis (84.2 vs. 53.1%; p = 0.01) and suffered from recurrent cholangitis more often (48.3 vs. 21.0%; p = 0.003). Patients with late-onset PSC had reduced transplantation-free survival (10.5 ± 0.6 years vs. 20.8 ± 1.7 years, p < 0.0001), with progredient liver failure and cholangiocarcinoma as the leading causes of death.

Conclusions

Patients with later age at diagnosis of PSC displayed a different clinical phenotype with a different sex ratio, immune status and an increased risk for progressive liver failure and biliary malignancies.

Inflammatory bowel disease in liver transplanted patients

Most common hepatobiliary manifestation of inflammatory bowel disease (IBD) are primary sclerosing cholangitis (PSC) and autoimmune hepatitis, ranking them as the main cause of liver transplantation (LT) in IBD setting. Course of pre-existing IBD after LT differs depending on many transplant related factors. Potential risk factors related to IBD deterioration after LT are tacrolimus-based immunosuppressive regimens, active IBD and cessation of 5-aminosalicylates at the time of LT. About 30% patients experience improvement of IBD after LT, while approximately the same percentage of patients worsens. Occurrence of de novo IBD may develop in 14%-30% of patients with PSC. Recommended IBD therapy after LT is equivalent to recommendations to overall IBD patients. Anti-tumor necrosis factor alpha appears to be efficient for refractory IBD. Due to potential side effects it needs to be applied with caution. In average 9% of patients require proctocolectomy due to medically refractory IBD or colorectal carcinoma. The most frequent complication in patients who undergo proctocolectomy with ileal-pouch anal anastomosis is pouchitis. It is still undeterminable if LT adds to risk of developing pouchitis in PSC patients. Annual colonoscopies are recommended as surveillance and precaution of colonic malignancies.

Genetics of primary sclerosing cholangitis and pathophysiological implications

Primary sclerosing cholangitis (PSC) is a chronic disease leading to fibrotic scarring of the intrahepatic and extrahepatic bile ducts, causing considerable morbidity and mortality via the development of cholestatic liver cirrhosis, concurrent IBD and a high risk of bile duct cancer. Expectations have been high that genetic studies would determine key factors in PSC pathogenesis to support the development of effective medical therapies. Through the application of genome-wide association studies, a large number of disease susceptibility genes have been identified. The overall genetic architecture of PSC shares features with both autoimmune diseases and IBD. Strong human leukocyte antigen gene associations, along with several susceptibility genes that are critically involved in T-cell function, support the involvement of adaptive immune responses in disease pathogenesis, and position PSC as an autoimmune disease. In this Review, we survey the developments that have led to these gene discoveries. We also elaborate relevant interpretations of individual gene findings in the context of established disease models in PSC, and propose relevant translational research efforts to pursue novel insights.