Incidence and prevalence of primary sclerosing cholangitis in a defined adult population in Sweden

The epidemiological trends and projected future of primary sclerosing cholangitis by 2040: An updated meta-analysis and modeling study

BACKGROUND AND AIMS

Primary sclerosing cholangitis (PSC) exhibits varying incidence and prevalence rates across different regions; however, comprehensive global studies examining its geographic distribution and future trends are scarce. This study presents an updated meta-analysis through 2024 and projects the global and regional prevalence of PSC from 2024 to 2040 using an illness-death multi-state model.

METHODS

We conducted a thorough systematic search across multiple databases to identify all primary studies published until 2024 that reported on the incidence, prevalence, and mortality rates of PSC in various regions. Using the gathered data, we developed an illness-death model to forecast the future prevalence of PSC, covering the years 2024-2040.

RESULTS

Our meta-analysis revealed that the global pooled incidence and prevalence rates of PSC are 0.65 and 7.52 per 100,000 persons, respectively. Projections indicate that the global prevalence of PSC will rise to 22.98 cases per 100,000 (95% CI: 21.0-24.95), corresponding to an overall increase of 28.3%. Specifically, North America is forecasted to experience a 5.45% increase in PSC cases, reaching 24.76 cases per 100,000 (95% CI: 19.63-29.88), while Western Europe is anticipated to see a more pronounced rise of 28.79%, resulting in a prevalence of 21.48 cases per 100,000 (95% CI: 18.3-24.65) by 2040.

CONCLUSIONS

Our findings indicate a substantial rise in the number of individuals affected by PSC in recent years and estimate a significant future burden of the disease.

Epidemiological and economical burden of cholestatic liver disease

The main cholestatic liver diseases comprise primary sclerosing cholangitis, primary biliary cholangitis, and IgG4-related cholangitis. Despite being classified as rare diseases, these are becoming gradually more important in the field of hepatology since their incidence is slowly rising while the viral hepatitis burden is declining. Cholestatic liver diseases now rank among the 3 most frequent indications for liver transplantation in many Western countries. An accurate understanding of the epidemiology and burden of disease on both the individual and society of cholestatic diseases is of great importance. This review aims to provide a comprehensive overview of the current literature on the epidemiology, health-related quality of life, and economic burden of primary sclerosing cholangitis, primary biliary cholangitis, and IgG4-related cholangitis.

Primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a chronic biliary inflammation associated with periductular fibrosis of the intrahepatic and extrahepatic bile ducts leading to strictures, bacterial cholangitis, decompensated liver disease and need for liver transplantation. This rare focal liver disease affects all races and ages, with a predominance of young males. There is an up to 88% association with inflammatory bowel disease. Although the aetiology is unknown and the pathophysiology is poorly understood, PSC is regarded as an autoimmune liver disease based on a strong immunogenetic background. Further, the associated risk for various malignancies, particularly cholangiocellular carcinoma, is also poorly understood. No medical therapy has been approved so far nor has been shown to improve transplant-free survival. However, ursodeoxycholic acid is widely used since it improves the biochemical parameters of cholestasis and is safe at low doses. MRI of the biliary tract is the primary imaging technology for diagnosis. Endoscopic interventions of the bile ducts should be limited to clinically relevant strictures for balloon dilatation, biopsy and brush cytology. End-stage liver disease with decompensation is an indication for liver transplantation with recurrent PSC in up to 38% of patients. Several novel therapeutic strategies are in various stages of development, including apical sodium-dependent bile acid transporter and ileal bile acid transporter inhibitors, integrin inhibitors, peroxisome proliferator-activated receptor agonists, CCL24 blockers, recombinant FGF19, CCR2/CCR5 inhibitors, farnesoid X receptor bile acid receptor agonists, and nor-ursodeoxycholic acid. Manipulation of the gut microbiome includes faecal microbiota transplantation. This article summarizes present knowledge and defines unmet medical needs to improve quality of life and survival.

Prevalence and bidirectional association between primary sclerosing cholangitis and Crohn's disease: A systematic review and meta-analysis

PURPOSE

This meta-analysis aimed to evaluating the prevalence of Crohn's disease in primary sclerosing cholangitis (PSC) and the incidence of primary sclerosing cholangitis in Crohn's disease (CD), along with their interrelation.

METHODS

An extensive search was conducted in the PubMed and Embase to identify available publications up to December 2023. Studies were included if they reported the prevalence of CD in PSC patients, or vice versa. Proportions were assessed using the DerSimonian and Laird method, followed by transformation via the Freeman-Tukey double inverse sine transformation. The quality of the included studies utilizing the Joanna Briggs Institute Critical Appraisal Checklist.

RESULTS

Based on quantitative analysis of 61 studies, the prevalence of PSC in patients with CD was 0.88% (95% CI: 0.53-1.30%). The prevalence of PSC in male CD patients was 0.45% (95% CI: 0.03-1.16%). In female CD patients, the prevalence was 0.51% (95% CI: 0.09-1.14%). The prevalence of CD with PSC was 11.27% (95% CI: 9.56-13.10%). The prevalence of CD in male PSC patients was 10.71% (95% CI: 7.42-14.50%). Among female PSC patients, the pooled prevalence of CD was 13.05% (95% CI: 11.05-15.19%).

CONCLUSIONS

We found a significant bidirectional association between PSC and CD, with a higher prevalence of CD in female with PSC compared to male. These findings provide important epidemiological data for clinical practice.

Incidence and Prevalence of Primary Sclerosing Cholangitis: A Meta-analysis of Population-based Studies

BACKGROUND

Primary sclerosing cholangitis is a chronic liver disease associated with significant morbidity, mortality, and healthcare utilization. We conducted a systematic review and meta-analysis of population-based studies of the incidence and prevalence of primary sclerosing cholangitis.

METHODS

Medline and Embase were systematically searched to identify population-based studies of a defined geographic area and reported the incidence or prevalence of primary sclerosing cholangitis in the general population. Meta-analyses, using random-effects, were performed to calculate overall and country-specific incidence (per 100 000 persons/year) and prevalence rates (per 100 000 persons) with 95% confidence intervals.

RESULTS

The 14 studies on incidence and the 12 for prevalence originated from North America, Asia, Europe, and Oceania. Incidence and prevalence rates of primary sclerosing cholangitis were 0.87 (95% confidence interval, 0.59-1.29) and 13.53 (95% confidence interval, 10.20-17.94) per 100 000 persons, respectively.

CONCLUSIONS

Both the prevalence and incidence of primary sclerosing cholangitis is low in the general population. Future studies on the incidence and prevalence of primary sclerosing cholangitis in the general population should be directed at Asia, Africa, and Latin America to allow for a more robust assessment of the global epidemiology of primary sclerosing cholangitis.

Caregiver-reported symptom burden and preferences for therapeutic goals in pediatric primary sclerosing cholangitis

This study analyzed qualitative and quantitative survey responses from 51 pediatric primary sclerosing cholangitis (PSC) patients and caregivers using the PSC Partners Patient Registry-Our Voices survey. The most common symptoms reported by children/caregivers include: fatigue (71%), abdominal pain (69%), anxiety (59%), appetite loss (51%), insomnia (49%), and pruritus (45%). When experiencing symptoms at their worst, over half of patients/caregivers reported limitations in physically demanding activities (67%), work/school duties (63%), social life activities (55%), and activities for fun or exercise (53%). Over half of patients/caregivers expressed willingness to participate in clinical trials, however none reported ever participating in trials for new or investigational PSC drugs. This study revealed a substantial patient/caregiver-reported symptom burden for children with PSC that impacts quality of life and limits access to clinical trials. Future efforts should focus on developing patient-centered clinical endpoints for PSC trials, increasing trial availability for pediatric PSC patients, and reducing logistical barriers to trial involvement.

It's Not Always Infections When It Comes to Resource-Poor Countries: A Fascinating Case Report

A patient's demographics often guide healthcare providers toward clues to a diagnosis. A recent travel history becomes an essential piece of the puzzle when there is a high suspicion of an infectious cause. When a patient walks into the hospital after having traveled to or from a resource-poor country with systemic afflictions, a physician's mind quickly jumps to infectious causes, and in most circumstances, it proves to be correct. We report an interesting case of a 28-year-old male from Guatemala who experienced acute gastrointestinal (GI) symptoms. Previous research in this field has shown that patients with inflammatory bowel disease (IBD) are prone to a slew of GI infections. Interestingly, our patient's presenting symptoms were initially attributed to "infections," but a thorough investigation revealed an unexpected twist of events. Our patient presented with multiple GI infections after the usual triggers, which masqueraded the coexistence of underlying primary sclerosing cholangitis and ulcerative colitis for a short course but were diagnosed promptly after a thorough workup.

Vascular adhesion protein-1 blockade in primary sclerosing cholangitis: Open-label, multicenter, single-arm, phase II trial

BACKGROUND

Primary sclerosing cholangitis is a progressive inflammatory liver disease characterized by biliary and liver fibrosis. Vascular adhesion protein-1 (VAP-1) is important in the inflammatory process driving liver fibrosis. We evaluated the safety and efficacy of VAP-1 blockade with a monoclonal antibody (timolumab, BTT1023) in patients with primary sclerosing cholangitis.

METHODS

BUTEO was a prospective, single-arm, open-label, multicenter, phase II trial, conducted in 6 centers in the United Kingdom. Patients with primary sclerosing cholangitis aged 18-75 years had an alkaline phosphatase value of >1.5 times the upper limit of normal. The dose-confirmatory stage aimed to confirm the safety of timolumab through the incidence of dose-limiting toxicity and sufficient trough levels of circulating antibody to block VAP-1 function. The primary outcome of the dose-expansion portion of the trial was patient's response to timolumab at day 99, as measured by a reduction in serum alkaline phosphatase by 25% or more from baseline to day 99.

RESULTS

Twenty-three patients were recruited: 7 into the initial dose-confirmatory stage and a further 16 into an expansion stage. Timolumab (8 mg/kg) was confirmed to be safe for the duration of administration with sufficient circulating levels. Only 2 of the 18 evaluable patients (11.1%) achieved a reduction in alkaline phosphatase levels of 25% or more, and both the proportion of circulating inflammatory cell populations and biomarkers of fibrosis remained unchanged from baseline.

CONCLUSIONS

The BUTEO trial confirmed 8 mg/kg timolumab had no short-term safety signals and resulted in sufficient circulating levels of VAP-1 blocking timolumab. However, the trial was stopped after an interim assessment due to a lack of efficacy as determined by no significant change in serum liver tests.

Rare liver diseases in Egypt: Clinical and epidemiological characterization

Illnesses that afflict a tiny number of individuals are referred to as rare diseases (RDs), sometimes called orphan diseases. The local healthcare systems are constantly under financial, psychological, and medical strain due to low incidence rates, unusual presentations, flawed diagnostic standards, and a lack of treatment alternatives for these RDs. The effective management of the once widely spread viral hepatitis B and C has altered the spectrum of liver diseases in Egypt during the last several years. The detection of uncommon disorders such as autoimmune, cholestatic, and hereditary liver diseases has also been made easier by the increasing knowledge and greater accessibility of specific laboratory testing. Finally, despite Egypt's large population, there are more uncommon liver disorders than previously thought. This review article discusses the clinical and epidemiological characteristics of a few uncommon liver disorders and the information currently accessible concerning these illnesses in Egypt.

Primary Sclerosing Cholangitis: Gender Effects in Valencia's Low-Prevalence Region

BACKGROUND AND AIMS

Recent studies point out to epidemiological changes in primary sclerosing cholangitis (PSC). Our aims were to determine in PSC patients followed in several centers in a Mediterranean geographic area: (i) changes in baseline features and (ii) effect of gender on clinical course.

METHODS

Retrospective multicenter study of PSC patients treated in 8 hospitals in a Mediterranean area between 2000 and 2021. Charts were reviewed compiling demographic, clinical, radiological, and histological variables.

RESULTS

Cohort of 112 PSC patients included, 42% women, 70% diagnosed after 2010. Women were increasingly diagnosed in recent cohorts. The median time from diagnosis to the combined endpoint liver transplantation (Lt) and/or death was 6.9 years. Asthenia at diagnosis (p = 0.009) was associated with lower transplant-free survival, while diagnosis before 2005 was associated with greater LT-free survival (p < 0.001). By Cox regression, LT-free survival was not influenced by age, sex, or cirrhosis at the time of diagnosis. Women were found to have less jaundice at diagnosis (2 vs 14%; p = 0.013), higher prevalence of ANA antibodies (43.9 vs 15.7%; p = 0.003), and lower GGT levels at diagnosis (GGT 123 vs 209U/L; p = 0.014) than men.

CONCLUSION

In an area traditionally considered to have low prevalence, the prevalence of affected women surpasses expectations based on existing literature. There appear to be gender-related variations in the presentation of the condition, highlighting the need for confirmation through larger-scale studies.

Epidemiology of autoimmune liver disease in Korea: evidence from a nationwide real-world database

BACKGROUND

Autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), and primary sclerosing cholangitis (PSC) are all immune-mediated chronic inflammatory liver diseases. Autoimmune liver diseases are rare, making identification and treatment difficult. To improve clinical outcomes and enhance patient quality of life, we performed an epidemiological study of autoimmune liver diseases based on real-world comprehensive data.

RESULTS

We used National Health Insurance Service claims data in Korea from 2005 to 2019. Patients were identified using the International Classification of Disease 10th Revision code, and rare intractable disease codes assigned according to the strict diagnostic criteria. In the AIH cohort, 8,572 (83.9%) were females and the mean age at diagnosis was 56.3 ± 14.3 years. PBC also showed female dominance (83.3%) and the mean age was 57.8 ± 12.6 years. Patients with PSC showed no sex predominance and had a mean age of 57.8 ± 21.5 years. During the study period, there were 10,212, 6,784, and 888 AIH, PBC, and PSC patients, respectively. The prevalence of AIH, PBC, and PSC in 2019 were 18.4, 11.8, and 1.5 per 100,000 population, while the corresponding incidences were 2.3, 1.4, and 0.3 per 100,000 population, respectively. Analysis of sex-age-standardized data showed that the annual prevalence of these diseases is increasing. The 10-year survival rates were 89.8%, 74.9%, and 73.4% for AIH, PBC, and PSC, respectively.

CONCLUSIONS

The number of patients with autoimmune liver disease in South Korea is increasing over time. Further research on autoimmune liver disease is needed to fulfill unmet clinical needs.

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.

Primary Sclerosing Cholangitis: Epidemiology, Diagnosis, and Presentation

Primary sclerosing cholangitis (PSC) is considered an immunologically mediated disease. However, some of its features are not consistent with the typical profile of autoimmune conditions. PSC is characterized by progressive biliary fibrosis that may ultimately result in the eventual development of cirrhosis. In recent years, multiple studies have reported that the incidence and prevalence of this disease are on the rise. Consequently, patients are often diagnosed without symptoms or signs of advanced liver disease, although many still present with signs of decompensated liver disease. This article discusses the epidemiology, clinical presentation, and diagnostic workup in patients with PSC.

Inflammatory bowel disease and primary sclerosing cholangitis: One disease or two?

Primary sclerosing cholangitis (PSC) was declared one of the biggest unmet needs in hepatology during International Liver Congress 2016 in Berlin. Since then, not much has changed unfortunately, largely due to the still elusive pathophysiology of the disease. One of the most striking features of PSC is its association with inflammatory bowel disease (IBD), with the majority of patients with PSC being diagnosed with extensive colitis. This review describes the epidemiology of IBD in PSC, its specific phenotype, complications and potential pathophysiological mechanisms connecting the two diseases. Whether PSC is merely an extra-intestinal manifestation of IBD or if PSC and IBD are two distinct diseases that happen to share a common susceptibility that leads to a dual phenotype is debated. Implications for the management of the two diseases together are also discussed. Overall, this review summarises the available data in PSC-IBD and discusses whether PSC and IBD are one or two disease(s).

Sex differences in chronic liver disease and benign liver lesions

The epidemiology, natural history, and therapeutic responses of chronic liver diseases and liver lesions often vary by sex. In this review, we summarize available clinical and translational data on these aspects of the most common liver conditions encountered in clinical practice, including the potential contributions of sex hormones to the underlying pathophysiology of observed differences. We also highlight areas of notable knowledge gaps and discuss sex disparities in access to liver transplant and potential strategies to address these barriers. Given established sex differences in immune response, drug metabolism, and response to liver-related therapies, emerging clinical trials and epidemiological studies should prioritize dedicated analyses by sex to inform sex-specific approaches to liver-related care.

Genetic link between primary sclerosing cholangitis and thyroid dysfunction: a bidirectional two-sample Mendelian randomization study

BACKGROUND

Observational studies have demonstrated an association between primary sclerosing cholangitis (PSC) and thyroid dysfunction (TD). However, the causal relationship between PSC and TD remains uncertain. The purpose of this study is to investigate the causal associations and specific direction between these two conditions. Gaining insight into the potential causal relationship between PSC and TD is valuable for elucidating the pathogenesis of PSC and for devising innovative approaches for the prevention and treatment of PSC and its associated complications.

METHODS

We conducted a bidirectional two-sample Mendelian randomization (MR) analysis to investigate the causal association between PSC and TD, such as autoimmune thyroid disease (AITD), thyroid cancer (TC), thyroid stimulating hormone (TSH), thyrotropin-releasing hormone (TRH), among others. PSC was the exposure variable, while TD was the outcome variable. To identify suitable instrumental variables (IVs), we utilized genome-wide association study (GWAS) datasets to select potential candidate single-nucleotide polymorphisms (SNPs). The primary statistical approach employed was the inverse-variance weighted (IVW) method, which was complemented by a series of sensitivity analyses to assess the robustness of the results by estimating heterogeneity and pleiotropy.

RESULTS

We found that the causal associations between genetically predicted PSC and Graves' disease (GD), hyperthyroidism (IVW OR=1.230, 95%CI: 1.089-1.389, P=0.001; IVW OR=1.001, 95%CI: 1.000-1.002, P=0.000) were statistically significant. The reverse MR analysis indicated that genetic susceptibility to hyperthyroidism (P=0.000) and hypothyroidism (p=0.028) might be the risk of PSC. There was no statistically significant causal association observed between PSC and other TD (IVW P>0.05), with the exception of GD, hyperthyroidism, and hypothyroidism as determined through bidirectional two-sample analysis. To ensure the reliability of our findings, additional sensitivity analyses were conducted, including the leave-one-out (LOO) test, heterogeneity test, and pleiotropic test.

CONCLUSION

In this study, we conducted an investigation into the causal association between PSC and TD. Our findings indicate that PSC significantly elevates the susceptibility to GD and hyperthyroidism from a statistical perspective. These results shed light on the etiology of PSC and have implications for the management of patients with PSC.

Liver transplant in patients with primary sclerosing cholangitis: A retrospective cohort from Northeastern Brazil

BACKGROUND

Primary sclerosing cholangitis (PSC) manifests within a broad ethnic and racial spectrum, reflecting different levels of access to health care.

AIM

To evaluate the clinical profile, complications and survival rates of patients with PSC undergoing liver transplantation (LTx) at a Brazilian reference center.

METHODS

All patients diagnosed with PSC before or after LTx were included. The medical records were reviewed for demographic and clinical variables, including outcomes and survival. The level of statistical significance was set at P < 0.05.

RESULTS

Our cohort represented 1.6% (n = 34) of the 2113 patients receiving liver grafts at our service over the past two decades. Most were male (n = 19; 56%). The average age (40 ± 14 years) was similar for men and women (P = 0.347). The mean follow-up time from diagnosis to LTx was 68 mo. Most patients had the classic form of PSC. Three women had PSC/autoimmune hepatitis overlap syndrome, and one patient had small-duct PSC. Alkaline phosphatase levels at diagnosis and pre-LTx model for end-stage liver disease. scores were significantly higher in males. Inflammatory bowel research (IBD) was investigated by colonoscopy in 26/34 (76%) and was present in most cases (18/26; 69%). IBD was less common in women than in men (44.4% vs. 55.6%) (P = 0.692). Cholangiocarcinoma (CCA) was diagnosed in 2/34 (5.9%) patients by histopathology of the explant (survival: 3 years 6 mo, and 4 years 11 mo). Two patients had complications requiring a second LTx (one after 7 d due to hepatic artery thrombosis and one after 17 d due to primary graft dysfunction). Five patients (14.7%) developed biliary stricture. The overall median post-LTx survival was 66 mo. Most deaths occurred in the first year (infection n = 2, primary liver graft dysfunction n = 3, unknown cause n = 1). The 1-year and 5-year survival rates of this cohort were 82.3% and 70.6%, respectively, matching the mean overall survival rates of LTx patients at our center (87.1% and 69.43%, respectively) (P = 0.83).

CONCLUSION

Survival after 1 and 5 years was similar to that of other LTx indications. The observed CCA survival rate suggests CCA may be an indication for LTx in selected cases.

The Origin and Fate of Liver Myofibroblasts

Liver fibrosis of different etiologies is a serious health problem worldwide. There is no effective therapy available for liver fibrosis except the removal of the underlying cause of injury or liver transplantation. Development of liver fibrosis is caused by fibrogenic myofibroblasts that are not present in the normal liver, but rather activate from liver resident mesenchymal cells in response to chronic toxic or cholestatic injury. Many studies indicate that liver fibrosis is reversible when the causative agent is removed. Regression of liver fibrosis is associated with the disappearance of activated myofibroblasts and resorption of the fibrous scar. In this review, we discuss the results of genetic tracing and cell fate mapping of hepatic stellate cells and portal fibroblasts, their specific characteristics, and potential phenotypes. We summarize research progress in the understanding of the molecular mechanisms underlying the development and reversibility of liver fibrosis, including activation, apoptosis, and inactivation of myofibroblasts.

The role of serology, liver function tests and imaging in screening of primary sclerosing cholangitis: the HelPSCreen score

OBJECIVES

At present, no sensitive or specific screening test exists for primary sclerosing cholangitis (PSC). PSC screening is mainly based on elevated alkaline phosphatase (ALP) in patients with inflammatory bowel disease (IBD). We aimed to produce a screening score based on laboratory tests to predict the likelihood of PSC. Moreover, we evaluated the additional roles of liver histology and magnetic resonance cholangiopancreatography (MRCP) in the diagnosis of PSC.

MATERIALS AND METHODS

The data of 385 patients who came for their first endoscopic retrograde cholangiography (ERC) to confirm PSC diagnosis were retrieved from the PSC registry of the Helsinki University Hospital. Overall, 69 patients referred for ERC with suspected PSC, in whom PSC was excluded by ERC or liver biopsy and MRCP, served as controls. We included patients' demographics and 13 laboratory test results in the analysis. Variables with significant odds ratios were selected for multivariate logistic regression, which was used to create a novel scoring system for PSC. The presence of IBD, serum perinuclear anti-neutrophil cytoplasmic antibodies, and ALP levels demonstrated the highest predictive value for PSC. A score was assigned for each statistically significant predictor.

RESULTS

The optimal cut-off point for the score was ≥3, with an AUC of 0.83 (95%CI: 0.78-0.88). The addition of liver histology or MRCP findings to the score did not add a predictive value.

CONCUSIONS

In conclusion, we created a novel, simple scoring system to screen the probability of PSC. The HelPSCreen-score may help to assess the disease prevalence and to target further investigations in patients suspected of PSC.

Good outcomes of living donor liver transplant in primary sclerosing cholangitis: an experience from North India

BACKGROUND

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease. In the absence of effective medical therapy, liver transplant is the definitive treatment for advanced stage. However, recurrence of PSC after liver transplant is of concern which can lead to graft failure and may require retransplant. There are limited data on outcomes of living donor liver transplant (LDLT) in PSC. Also, in LDLT as donors are genetically related there can be an increased risk of recurrence. We conducted this retrospective study to analyze the outcomes of LDLT in PSC at a tertiary liver transplant center in north India.

METHODS

We conducted a retrospective analysis of 3213 transplant recipients who underwent LDLT from January 2006 to May 2021. Of these 26 (0.80%) patients had PSC as indication for liver transplantation (PSC = 24, PSC-AIH overlap = 2). Data analysis was done to look for baseline demographics, clinical details, transplant outcomes, PSC recurrence, and survival.

RESULTS

Mean age of study group was 42 (± 13.8) years and 19 patients (73.1%) were males. All patients had decompensated cirrhosis at the time of transplant. Mean CTP score and MELD score were 9.5 (± 1.8) and 18.9 (± 7.1), respectively. Sixteen patients received modified right lobe graft, seven extended right lobe graft and five patients received left lateral graft. Median graft weight and mean graft to recipient weight ratio (GRWR) were 633.5 (IQR 473.5-633.5) grams and 1.23 (± 0.42), respectively. Most common biliary anastomosis was hepaticojejunostomy, done in 19 (73.1%) while duct to duct anastomosis was performed in 7 (26.9%) patients. Median follow-up was 96 (36-123) months. One patient had ulcerative colitis and none had cholangiocarcinoma. Two (7.7%) patients had bile leak during early post-transplant period. Three (11.1%) patients developed graft rejection and were managed successfully with steroid pulses. Three patients died during early post-transplant period while seven deaths occurred during long-term follow-up including one death due to COVID-19. Five (21.73%) patients had recurrence of PSC of which two patients had graft loss including one after retransplantation. The one year graft and patient survival rate was 88.5%.

CONCLUSION

LDLT can be performed in PSC with good long-term outcomes with a risk of PSC recurrence in about one-fifth patients.

The microbiota and the gut-liver axis in primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) offers unique opportunities to explore the gut-liver axis owing to the close association between liver disease and colonic inflammation. It is well established that the gut microbiota in people with PSC differs from that of healthy individuals, but details of the microbial factors that demarcate PSC from inflammatory bowel disease (IBD) without PSC are poorly understood. In this Review, we aim to provide an overview of the latest literature on the gut microbiome in PSC and PSC with IBD, critically examining hypotheses on how microorganisms could contribute to the pathogenesis of PSC. A particular emphasis will be put on pathogenic features of the gut microbiota that might explain the occurrence of bile duct inflammation and liver disease in the context of IBD, and we postulate the potential existence of a specific yet unknown factor related to the gut-liver axis as causative in PSC. Available data are scrutinized in the perspective of therapeutic approaches related to the gut-liver axis.

Inflammatory conditions play a role in recurrence of PSC after liver transplantation – an international multicentre study

Background & Aims

Liver transplantation (LT) for primary sclerosing cholangitis (PSC) is complicated by recurrence of PSC (rPSC) in up to 25% of recipients. Recurrence has been shown to be detrimental for both graft and patient survival. For both PSC and rPSC, a medical cure is not available. To predict and ideally to prevent rPSC, it is imperative to find risk factors for rPSC that can be potentially modified. Therefore, we aimed to identify such factors for rPSC in a large international multicentre study including 6 centres in PSC-prevalent countries.

Methods

In this international multicentre, retrospective cohort study, 531 patients who underwent transplantation for PSC were included. In 25% of cases (n = 131), rPSC was diagnosed after a median follow-up of 6.72 (3.29–10.11) years post-LT.

Results

In the multivariable competing risk model with time-dependent covariates, we found that factors representing an increased inflammatory state increase the risk for rPSC. Recurrent cholangitis before LT as indication for LT (hazard ratio [HR] 3.6, 95% CI 2.5–5.2), increased activity of inflammatory bowel disease after LT (HR 1.7, 95% CI 1.08–2.75), and multiple acute cellular rejections (HR: non-linear) were significantly and independently associated with an increased risk of rPSC. In contrast to the findings of previous studies, pretransplant colectomy was not found to be independently protective against the development of rPSC.

Conclusions

An increased inflammatory state before and after LT may play a causal and modifiable role in the development of rPSC. Pretransplant colectomy did not reduce the risk of rPSC per se. Recurrent cholangitis as indication for LT was associated with an increased risk of rPSC.

Impact and implications

Recurrence of PSC (rPSC) negatively affects survival after liver transplant (LT). Modifiable risk factors could guide clinical management and prevention of rPSC. We demonstrate that an increased inflammatory state both before and after LT increases the incidence of rPSC. As these are modifiable factors, they could serve as targets for future studies and therapies. We also added further evidence to the ongoing debate regarding preventive colectomy for rPSC by reporting that in our multicenter study, we could not find an independent association between colectomy and risk of rPSC.

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rPSC occurred after LT in 25% of recipients in this multicentre study from 6 transplant centres (Europe and North America).

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An increased systemically inflammatory state, both before and after LT, increases the risk of rPSC development.

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Increased IBD activity post-LT was associated with a higher risk of rPSC development.

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Performing a colectomy before LT was not associated with a reduction of rPSC.

Cellular and transcriptional heterogeneity in the intrahepatic biliary epithelium

Epithelial tissues comprise heterogeneous cellular subpopulations, which often compartmentalize specialized functions like absorption and secretion to distinct cell types. In the liver, hepatocytes and biliary epithelial cells (BECs; also called cholangiocytes) are the two major epithelial lineages and play distinct roles in (1) metabolism, protein synthesis, detoxification, and (2) bile transport and modification, respectively. Recent technological advances, including single cell transcriptomic assays, have shed new light on well-established heterogeneity among hepatocytes, endothelial cells, and immune cells in the liver. However, a "ground truth" understanding of molecular heterogeneity in BECs has remained elusive, and the field currently lacks a set of consensus biomarkers for identifying BEC subpopulations. Here, we review long-standing definitions of BEC heterogeneity as well as emerging studies that aim to characterize BEC subpopulations using next generation single cell assays. Understanding cellular heterogeneity in the intrahepatic bile ducts holds promise for expanding our foundational mechanistic knowledge of BECs during homeostasis and disease.

Prevalence of inflammatory bowel disease in patients with primary sclerosing cholangitis: A systematic review and meta-analysis

BACKGROUND AND AIM

Previous studies have established an association between primary sclerosing cholangitis (PSC) and inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis (UC). The disease burden of IBD in PSC patients was not well estimated. The study aimed to quantify the pooled prevalence of IBD in PSC and to investigate whether subtypes of PSC and sex influence the prevalence of IBD.

METHODS

PubMed, Embase, and Web of Science were searched through November 2021 for studies reporting data on IBD among PSC patients. The outcomes were the prevalence of IBD in patients with PSC, as well as the association (odds ratio [OR]) of IBD in PSC according to subtype and sex.

RESULTS

Based on the analysis of 25 studies, the prevalence of IBD in patients with PSC was 71.1% (95% CI 68.2-75.1%), most commonly in UC (55.9%, 95% CI 52.5-59.3%). The pooled prevalence of IBD was 76.9% in Australia (95% CI 71.2-82.6%, 1 study), 75.9% (95% CI 69.5-82.3%, 4 studies) in North America, 70.9% (95% CI 65.8-76.0%, 17 studies) in Europe and 67.0% (95% CI 57.9-76.0%, 2 studies) in Asia. Male PSC patients had a higher prevalence of IBD (OR 1.67, 95% CI 1.52-1.83) and UC (OR 2.02, 95% CI 1.56-2.63) and a lower prevalence of CD (OR 0.77, 95% CI 0.67-0.88) than female patients. Large duct PSC patients had a higher prevalence of IBD (OR 2.57, 95% CI 2.03-3.25) and UC (OR 4.51, 95% CI 1.22-16.71) than small duct PSC patients.

CONCLUSIONS

The study provided the first pooled estimates of the burden of IBD in patients with PSC and could be used as the basis for risk stratification of PSC patients.

Epidemiology, Natural History, and Outcomes of Primary Sclerosing Cholangitis: A Systematic Review of Population-based Studies

BACKGROUND & AIMS

The aim of this study was to quantify the global epidemiology of primary sclerosing cholangitis (PSC), alongside the incidence of liver transplantation, cancer, and death, through robust systematic review of population-based data.

METHODS

We searched MEDLINE and EMBASE up to and including June 30, 2020 to identify population-based studies reporting the incidence and/or prevalence of PSC. Studies that did not report original data, or of exclusively pediatric-onset disease (diagnosis age <16 years) or exclusively PSC-associated with inflammatory bowel disease were excluded.

RESULTS

Of 4922 published studies, 17 fulfilled inclusion criteria; 16 documenting incidence and 14 prevalence. The highest reported incidence of PSC was reported in Northern Europe (Finland, 1.58 and Norway, 1.3 per-100,000 population, respectively) and North America (Minnesota, 1.47); with the lowest being observed across the Mediterranean Basin (Italy, 0.1). Prevalence ranged from 31.7 in Finland and 23.99 in Minnesota, to 1.33 in Singapore and 0.0 in Alaska. Of studies reporting temporal occurrence, an increase in disease incidence was observed across North America and Northern Europe (4 studies), alongside an increase in prevalence over time (4 studies). The incidence and risks for clinical outcomes were presented by 9 of the included studies. Median transplant-free survival ranged from 9.7 (United States) to 20.6 years (Netherlands), with standardized mortality ratios of 2.5 and 4.2 compared with the control population. The standardized incidence of cholangiocarcinoma ranged from 235 (Finland) to 398 (Netherlands).

CONCLUSIONS

Estimates of PSC incidence and prevalence vary, with most studies conducted in North America and Western Europe; the latter showing a steady increase in disease occurrence over time. Further research is needed to understand changes in disease epidemiology, including etiological drivers, the implications of rising case burden on health care policy, and better appreciation of PSC in the developing world.

Gender and Autoimmune Liver Diseases: Relevant Aspects in Clinical Practice

Autoimmune liver diseases (AILDs) include autoimmune hepatitis, primary biliary cholangitis and primary sclerosing cholangitis. The etiologies of AILD are not well understood but appear to involve a combination of genetic and environmental factors. AILDs commonly affect young individuals and are characterized by a highly variable clinical course. These diseases significantly influence quality of life and can progress toward liver decompensation or the onset of hepatocellular or cholangiocarcinoma; a significant number of patients eventually progress to end-stage liver disease, requiring liver transplantation. In this review, we focus on the sex characteristics and peculiarities of AILD patients and highlight the relevance of a sex-specific analysis in future studies. Understanding the sex differences underlying AILD immune dysregulation may be critical for developing more effective treatments.

PSC associated inflammatory bowel disease: a distinct entity

INTRODUCTION

Primary sclerosing cholangitis (PSC) is a rare, chronic, and progressive cholestatic disease involving intra- and/or extrahepatic bile ducts. PSC in many patients results in end-stage liver diseases. Nearly 60% of the PSC patients suffer from concomitant inflammatory bowel diseases (IBDs). Classically, IBDs are divided into two principle types: Crohn's disease (CD) and ulcerative colitis (UC). However, with growing knowledge, PSC-associated IBD (PSC-IBD) seems to be a rather distinct entity with specific genetics, clinical, and microbiota characteristics.

AREAS COVERED

In this article, we aim to review the unique characteristics of PSC-IBD from clinical, genetic, and microbiota point of view.

EXPERT OPINION

PSC-IBD's unique characteristics contribute to the notion that it could be a distinct entity. Acknowledgment of PSC-IBD as a novel entity necessitates designing new clinical guidelines for diagnosis and developing novel therapies.

The Epidemiology of UK Autoimmune Liver Disease Varies With Geographic Latitude

BACKGROUND & AIMS

The epidemiology of autoimmune liver disease (AILD) is challenging to study because of the diseases' rarity and because of cohort selection bias. Increased incidence farther from the Equator has been reported for multiple sclerosis, another autoimmune disease. We assessed the incidence of primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC), and autoimmune hepatitis (AIH) in relation to latitude.

METHODS

We performed a retrospective cohort study using anonymized UK primary care records from January 1, 2002, to May 10, 2016. All adults without a baseline diagnosis of AILD were included and followed up until the first occurrence of an AILD diagnosis, death, or they left the database. Latitude was measured as registered general practice rounded down to whole degrees.

RESULTS

The cohort included 8,590,421 records with 53.3 × 10⁷ years of follow-up evaluation from 694 practices. There were 1314 incident cases of PBC, 396 of PSC, and 1034 of AIH. Crude incidences were as follows: PBC, 2.47 (95% CI, 2.34-2.60); PSC, 0.74 (95% CI, 0.67-0.82); and AIH, 1.94 (95% CI, 1.83-2.06) per 100,000 per year. PBC incidence correlated with female sex, smoking, and deprivation; PSC incidence correlated with male sex and non-smoking; AIH incidence correlated with female sex and deprivation. A more northerly latitude was associated strongly with incidence of PBC: 2.16 (95% CI, 1.79-2.60) to 4.86 (95% CI, 3.93-6.00) from 50°N to 57°N (P = .002) and incidence of AIH: 2.00 (95% CI, 1.65-2.43) to 3.28 (95% CI, 2.53-4.24) (P = .003), but not incidence of PSC: 0.82 (95% CI, 0.60-1.11) to 1.02 (95% CI, 0.64-1.61) (P = .473). Incidence after adjustment for age, sex, smoking, and deprivation status showed similar positive correlations for PBC and AIH with latitude, but not PSC. Incident AIH cases were younger at more northerly latitude.

CONCLUSIONS

We describe an association in the United Kingdom between more northerly latitude and the incidence of PBC and AIH that requires both confirmation and explanation.

Clinical Features and Outcomes of Primary Sclerosing Cholangitis in the Highly Admixed Brazilian Population

BACKGROUND

Primary sclerosing cholangitis (PSC) is associated with a broad phenotypic spectrum in different populations from diverse ethnic and racial backgrounds. This study aimed to describe the clinical characteristics and outcomes of PSC in a multicenter cohort of patients from Brazil.

METHODS

Data from the Brazilian Cholestasis Study Group were retrospectively reviewed to assess demographic information and clinical characteristics of PSC, as well as the outcomes, such as transplantation-free survival.

RESULTS

This cohort included 210 patients. After excluding 33 (15.7%) patients with PSC and overlap syndrome of autoimmune hepatitis, 177 (97 males, median age 33 (21-42) years) with clear-cut PSC were eligible for this study. Most of the patients (n = 139, 78.5%) were symptomatic, and 104 (58.7%) had advanced PSC at the time of diagnosis. Concurrent inflammatory bowel disease was observed in 78 (58.6%) of the investigated patients (n = 133), and most of them had ulcerative colitis (n = 61, 78.2%). The 1- and 5-year survival free of liver transplantation or death were 92.3 ± 2.1% and 66.9 ± 4.2%, respectively, and baseline advanced PSC, pruritus, and elevated bilirubin levels were independent risk factors for the composite adverse outcome. Females were significantly older and had lower bilirubin levels than males at baseline, but survival was not associated with sex. Approximately 12.4% (n = 22) of patients with PSC died, and 32.8% (n = 58) underwent liver transplantation at a median follow-up time of 5.3 and 3.2 years.

CONCLUSION

Multiethnic Brazilian PSC patients exhibited a less pronounced male predominance and a lower frequency of inflammatory bowel disease than Caucasians. Adverse outcomes were more frequent, probably due to advanced disease at baseline.

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.

Global incidence, prevalence and features of primary sclerosing cholangitis: A systematic review and meta-analysis

BACKGROUND & AIMS

Primary sclerosing cholangitis (PSC) is an idiopathic, cholestatic liver disease with a diverse range of clinical manifestations. Inter-regional data on PSC are variable, but its global geoepidemiology has not been well-studied. We aimed to examine the worldwide incidence, prevalence and features of PSC and PSC-inflammatory bowel disease (PSC-IBD).

METHODS

A systematic search of multiple databases was conducted to identify all original, full-text studies until December 2020 with data regarding the incidence rate (IR) and/or prevalence of PSC. Outcomes were PSC IR, prevalence, features and IBD concurrence. Additionally, a meta-analysis of PSC IR was performed. The study was registered in PROSPERO (CRD42021224550).

RESULTS

Of the 1003 studies identified, 17 studies spanning three continents were included. PSC IR was 0.60 per 100 000 person-years (PY) (95% confidence interval: 0.37-0.88 per 100 000 PY). In pooled subgroup analysis for studies conducted in Europe and North America, PSC IR was 0.62 and 0.53 per 100 000 PY, respectively. PSC prevalence ranged 0-31.7 per 100 000 persons, with notable inter-regional differences. Mean age at PSC diagnosis was bimodally distributed, with relative peaks at 15 and 35 years. Mean concurrence of IBD with PSC was 50%, with 76% having ulcerative colitis, 17% Crohn's disease and 8% indeterminate/unspecified IBD.

CONCLUSION

While considerable heterogeneity exists in the geoepidemiology of PSC, overall, the classical dogmata of male predilection, bimodal distribution of mean age and high PSC-IBD concurrence appear to hold true. Despite a seemingly stable IR over time, further studies are needed to better understand the geoepidemiology of PSC.

Recent advances in clinical practice: epidemiology of autoimmune liver diseases

Autoimmune liver diseases are chronic inflammatory hepatobiliary disorders that when classically defined encompass three distinctive clinical presentations; primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC) and autoimmune hepatitis (AIH). Meaningful changes in disease epidemiology are reported, with increasing incidence and prevalence of AIH and PSC in Europe, and rising prevalence of PBC across Europe, North America and the Asia-Pacific region. However, there appears to be very significant global variation with contemporary incidence rates of disease per 100 000 ranging from 0.84 to 2.75 for PBC, 0.1 to 4.39 for PSC and 0.4 to 2.39 for AIH. Prevalence corresponds, and per 100 000 estimates for PBC range from 1.91 to 40.2, for PSC between 0.78 and 31.7 and for AIH from 4.8 to 42.9. Population-based studies and multicentre observational cohort series provide improved understanding of the clinical course that patients experience, highlighting variations in presenting phenotypes geographically and temporally. Collectively, while autoimmune liver diseases are rare, the clinical burden is disproportionately high relative to population incidence and prevalence. Age, sex and race also impact clinical outcomes, and patient morbidity and mortality are reflected by high need for gastroenterology, hepatology and organ transplant services.

Risk factors, epidemiology and prognosis of cholangiocarcinoma in Finland

Background

Cholangiocarcinoma (CCA) is a cancer arising from the intra‐ and extrahepatic bile ducts. The early stages are often asymptomatic, CCA is frequently diagnosed in an advanced stage and the prognosis of CCA is often dismal.

Objective

Our objective was to estimate the incidence of CCA in Finland and to identify risk factors for CCA, with a special interest in primary sclerosing cholangitis (PSC).

Methods

We identified all CCA cases during 1974–2018 from the Finnish Cancer Registry and calculated age‐standardised incidence rates. Five controls for each case were extracted from the Population Registry, matched by age, gender and municipality of residence at the time of diagnosis. Odds ratios (ORs) for risk factors were estimated with conditional logistic regression and survival estimates with the Kaplan–Meier method.

Results

Incidence of CCA remained stable in both genders; the age‐standardised rate (World Standard) in 2013–2017 in males and females was 1.7 per 100,000 person years and 1.3 per 100,000 person years, respectively. Primary sclerosing cholangitis carried a 30‐fold risk of intrahepatic cholangiocarcinoma (iCCA) and 25‐fold risk of extrahepatic cholangiocarcinoma (eCCA). Diabetes, inflammatory bowel disease and liver cirrhosis were associated with iCCA, whereas cholelithiasis and viral hepatitis C were associated with eCCA. The cumulative 5‐year survival was 4.6%.

Conclusions

The incidence of CCA has been stable. Known risk factors for CCA were confirmed, with PSC having the highest OR. Survival remains poor.

Recurrence of primary sclerosing cholangitis after liver transplantation - analysing the European Liver Transplant Registry and beyond

Liver transplantation for primary sclerosing cholangitis (PSC) can be complicated by recurrence of PSC (rPSC). This may compromise graft survival but the effect on patient survival is less clear. We investigated the effect of post‐transplant rPSC on graft and patient survival in a large European cohort. Registry data from the European Liver Transplant Registry regarding all first transplants for PSC between 1980 and 2015 were supplemented with detailed data on rPSC from 48 out of 138 contributing transplant centres, involving 1,549 patients. Bayesian proportional hazards models were used to investigate the impact of rPSC and other covariates on patient and graft survival. Recurrence of PSC was diagnosed in 259 patients (16.7%) after a median follow‐up of 5.0 years (quantile 2.5%‐97.5%: 0.4–18.5), with a significant negative impact on both graft (HR 6.7; 95% CI 4.9–9.1) and patient survival (HR 2.3; 95% CI 1.5–3.3). Patients with rPSC underwent significantly more re‐transplants than those without rPSC (OR 3.6, 95% CI 2.7–4.8). PSC recurrence has a negative impact on both graft and patient survival, independent of transplant‐related covariates. Recurrence of PSC leads to higher number of re‐transplantations and a 33% decrease in 10‐year graft survival.

Cholestatic Liver Disease: Current Treatment Strategies and New Therapeutic Agents

Cholestatic liver disease is a disease that causes liver damage and fibrosis owing to bile stasis. It is represented by primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC), but the pathophysiological pathways that cause bile stasis in both diseases are different. The pathogenesis of the disease is still unclear, although autoimmune mechanisms have been postulated and partially elucidated. Although the disease may progress slowly with only mild liver dysfunction, it may progress to liver cirrhosis or liver failure, which require liver transplantation. As a medical treatment, ursodeoxycholic acid is widely used for PBC and has proved to be very effective against disease progression in cases of PBC. On the other hand, its efficacy is limited in cases of PSC, and the research and development of various drugs are underway. Furthermore, the clinical course of both diseases is quite variable, making the design of clinical trials fairly difficult. In this review, we present the general natural history of PBC and PSC, and provide information on the latest drug therapies currently available and those that are under investigation.

Fibrotic Events in the Progression of Cholestatic Liver Disease

Cholestatic liver diseases including primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) are associated with active hepatic fibrogenesis, which can ultimately lead to the development of cirrhosis. However, the exact relationship between the development of liver fibrosis and the progression of cholestatic liver disease remains elusive. Periductular fibroblasts located around the bile ducts seem biologically different from hepatic stellate cells (HSCs). The fibrotic events in these clinical conditions appear to be related to complex crosstalk between immune/inflammatory mechanisms, cytokine signalling, and perturbed homeostasis between cholangiocytes and mesenchymal cells. Several animal models including bile duct ligation (BDL) and the Mdr2-knockout mice have improved our understanding of mechanisms underlying chronic cholestasis. In the present review, we aim to elucidate the mechanisms of fibrosis in order to help to identify potential diagnostic and therapeutic targets.

Primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a rare chronic cholestatic liver disease characterized by inflammatory destruction of the intrahepatic and/or extrahepatic bile ducts, leading to bile stasis, fibrosis, and ultimately to cirrhosis, and often requires liver transplantation (LT). PSC occurs more commonly in men, and is typically diagnosed between the ages of 30 and 40. Most cases occur in association with inflammatory bowel disease (IBD), which often precedes the development of PSC. PSC is usually diagnosed after detection of cholestasis during health evaluation or screening of patients with IBD. When symptomatic, the most common presenting symptoms are abdominal pain, pruritus, jaundice or fatigue. The etiology of PSC is poorly understood, but an increasing body of evidence supports the concept of cholangiocyte injury as a result of environmental exposure and an abnormal immune response in genetically susceptible individuals. PSC is a progressive disease, yet no effective medical therapy for halting disease progression has been identified. Management of PSC is mainly focused on treatment of symptoms and addressing complications. PSC can be complicated by bacterial cholangitis, dominant strictures (DSs), gallbladder polyps and adenocarcinoma, cholangiocarcinoma (CCA) and, in patients with IBD, colorectal malignancy. CCA is the most common malignancy in PSC with a cumulative lifetime risk of 10-20%, and accounts for a large proportion of mortality in PSC. LT is currently the only life-extending therapeutic approach for eligible patients with end-stage PSC, ultimately required in approximately 40% of patients. LT secondary to PSC has an excellent outcome compared to other LT indications, although the disease can recur and result in morbidity post-transplant.

Recent advances in the treatment of primary sclerosing cholangitis

Introduction: PSC is a rare liver disease that leads frequently to cirrhosis and need for liver transplantation. No medical treatment is of proven value. Liver transplantation is the only curative therapy available. There is a big medical need to find medical therapy that can alter the natural history of the disease.Areas covered: The authors highlight advances in PSC, based on recent literature retrieved from PubMed until September 2020 regarding both medical and endoscopic biliary therapy.Future possibilities for treatment of PSC are discussed.Expert opinion: Biliary endoscopy is the cornerstone in the treatment of dominant strictures. Single-user peroral cholangioscopy is an emerging modality. Balloon dilatation therapy is the treatment of choice of dominant strictures. The most promising medical therapies showing efficacy in phase II trials are nor-Ursodeoxycholic acid, obethicolic acid, the non-steroidal FXR agonist Cilofexor and Aldafermin, a synthetic analogue of FGF-19. Antibiotics, particularly vancomycin have shown potential benefits, particularly in children but phase III studies are lacking. In observational studies of effects of biological therapy in patients with IBD/PSC adalimumab was associated with reduction in ALP. Results of liver transplantation are favorable but recurrence can be of clinical relevance particularly in patients transplanted before the age of 40.

A nationwide population-based prospective study of cirrhosis in Iceland

Background & Aims

The incidence of cirrhosis in Iceland has been the lowest in the world with only 3 cases per 100,000 inhabitants. Alcohol consumption has almost doubled in Iceland from 1980 to 2016. Obesity has also risen and hepatitis C virus has spread among people who inject drugs in Iceland. The aim of this study was to evaluate the effects of these risk factors on the incidence and aetiology of cirrhosis in Iceland.

Methods

The study included all patients diagnosed with cirrhosis for the first time during 2010–2015. Diagnosis was based on liver histology or 2 of 4 criteria: cirrhosis on imaging, ascites, varices, and/or elevated INR.

Results

Overall, 157 patients were diagnosed, 105 (67%) males, mean age 61 years. The overall incidence was 9.7 cases per 100,000 inhabitants annually. Alcohol was the only underlying cause in 48/157 (31%), non-alcoholic fatty liver disease (NAFLD) in 34/157(22%), and alcohol and hepatitis C together in 23/157(15%) were the most common causes. Only 6% of patients had an unknown cause of cirrhosis. Upon diagnosis, the median model for end-stage liver disease score was 11 (IQR 8–15), 53% were of Child-Pugh class A whereas 61 (39%) had ascites, 11% encephalopathy, and 8% variceal bleeding. In all, 25% of deaths were from HCC and 25% from liver failure.

Conclusion

A major increase in incidence of cirrhosis has occurred in Iceland associated with increases in alcohol consumption, obesity, and hepatitis C. In a high proportion NAFLD was the aetiology and very few had unknown cause of cirrhosis. The highest death rate was from HCC.

Lay summary

In a nationwide population-based study from Iceland, including all patients diagnosed with cirrhosis of the liver over a period of 5 years, we found the incidence of new cases had increased 3-fold compared with a previous study 20 years ago. The increase is attributable to increased alcohol consumption, an epidemic of diabetes and obesity, and infection with the hepatitis C virus. Furthermore, we found that with thorough investigations, a specific cause for cirrhosis could be found in 94% of patients. Patients with cirrhosis frequently die of liver cancer and other complications related to their liver disease.

•

The incidence of cirrhosis in Iceland has been the lowest among western countries.

•

In this nationwide prospective study, all patients diagnosed with cirrhosis of the liver in Iceland over a period of 5 years were included.

•

The incidence of cirrhosis had increased 3-fold compared with a study 10 years earlier owing to increased alcohol consumption, obesity, and hepatitis C.

•

With thorough investigations a specific cause for cirrhosis could be found in 94% of patients.

Trends in Incidence of Autoimmune Liver Diseases and Increasing Incidence of Autoimmune Hepatitis

BACKGROUND & AIMS

Autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), and primary sclerosing cholangitis (PSC) are autoimmune liver diseases of unknown etiology. We studied trends in incidences of AIH, PBC, and PSC in a population-based prospective study Canterbury, New Zealand.

METHODS

We collected data on patients with AIH (n = 99), PBC (n = 26), or PSC (n = 47) from public hospitals and private practices in Canterbury from 2008 through 2016. Diagnoses were made based on international standardized criteria. We calculated incidence rates for the time periods of 2008-2010, 2011-2013, and 2014-2016 and compared them using 2-tailed mid-P exact tests.

RESULTS

Overall incidence rates were 1.93 per 100,000 for AIH (95% CI, 1.58-2.34), 0.51 per 100,000 for PBC (95% CI, 0.33-0.73), and 0.92 per 100,000 for PSC (95% CI, 0.68-1.21). The incidence of AIH was significantly higher during the period of 2014-2016 (2.39 per 100,000; 95% CI, 1.76-3.23) than during the period of 2008-2010 (1.37 per 100,000; 95% CI, 0.91- 2.06) (P < .05). Incidences of PBC and PSC did not change significantly. In 2016, prevalence values were 27.4 per 100,000 for AIH (95% CI, 23.58-32.0), 9.33 per 100,000 for PBC (95% CI, 7.13-12.05), and 13.17 per 100,000 for PSC (95% CI, 10.56-16.42).

CONCLUSIONS

In a population-based prospective study, we found that the incidence of AIH was significantly higher in the 2014-2016 period than the 2008-2010 period; incidences of PBC and PSC were unchanged over the same period. Further studies are needed to determine the reasons for changes in incidence of autoimmune liver diseases.

Mesenchymal stem cell-based treatment in autoimmune liver diseases: underlying roles, advantages and challenges

Autoimmune liver disease (AILD) is a series of chronic liver diseases with abnormal immune responses, including autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), and primary sclerosing cholangitis (PSC). The treatment options for AILD remain limited, and the adverse side effects of the drugs that are typically used for treatment frequently lead to a low quality of life for AILD patients. Moreover, AILD patients may have a poor prognosis, especially those with an incomplete response to first-line treatment. Mesenchymal stem cells (MSCs) are pluripotent stem cells with low immunogenicity and can be conveniently harvested. MSC-based therapy is emerging as a promising approach for treating liver diseases based on their advantageous characteristics of immunomodulation, anti-fibrosis effects, and differentiation to hepatocytes, and accumulating evidence has revealed the positive effects of MSC therapy in AILD. In this review, we first summarize the mechanisms, safety, and efficacy of MSC treatment for AILD based on work in animal and clinical studies. We also discuss the challenges of MSC therapy in clinical applications. In summary, although promising data from preclinical studies are now available, MSC therapy is currently far for being applied in clinical practice, thus developing MSC therapy in AILD is still challenging and warrants further research.

Factors associated with major radiological progression of primary sclerosing cholangitis in patients with inflammatory bowel disease

BACKGROUND/PURPOSE OF THE STUDY

Primary sclerosing cholangitis (PSC) is the most common hepatobiliary manifestation of inflammatory bowel disease (IBD). Magnetic resonance cholangiography (MRC) has become the primary diagnostic modality for PSC. However, data on radiological progression over time of large-duct PSC-IBD are limited.

METHODS

We performed a nested case-control study to estimate the frequency of PSC in adult patients with IBD from a Middle Eastern population to assess the risk factors associated with major disease progression (formation of dominant strictures or cholangiocarcinoma) over time.

RESULTS

Data of IBD patients who were registered in the Saudi IBD Information System at tertiary care center were analyzed. Among 960 patients [477 ulcerative colitis (UC); 483 Crohn's disease (CD)], 40 PSC-IBD patients with at least two MRC performed in a one-year interval were matched with 141 IBD patients without PSC. The frequency of PSC was 4.1%. UC patients (6.2%) compared to CD (2%), 65% had extensive colitis. The incidence rate of PSC among our cohort was increased from 2.62 to 10 per 1000 patient-years between 2005 and 2019. MRC features stabilized in (46.7%); worsened in (36.9%) and 15.4% of patients developed CCA. Alkaline phosphatase (ALP) levels of PSC patients who had major changes or CCA increased significantly after 44 months of follow-up (p = 0.01). The propensity score adjusted showed that hospitalization rate among PSC patients was higher than their non-PSC counterparts (OR 8.24; 95% CI 3.16-21.47; p < 0.01).

CONCLUSION

ALP rise and hospitalization history as clinical outcome were the only factors associated with PSC-IBD major progression on MRCP.

Contemporary Epidemiology of Chronic Liver Disease and Cirrhosis

BACKGROUND & AIMS

Accurate estimates for the contemporary burden of chronic liver disease (CLD) are vital for setting clinical, research, and policy priorities. We aimed to review the incidence, prevalence, and mortality of CLD and its resulting complications, including cirrhosis and hepatocellular carcinoma (HCC).

METHODS

We reviewed the published literature on the incidence, prevalence, trends of various etiologies of CLD and its resulting complications. In addition, we provided updated data from the Centers for Disease Control and Global Burden of Disease Study on the morbidity and mortality of CLD, cirrhosis, and hepatocellular carcinoma (HCC). Lastly, we assessed the strengths and weaknesses of available sources of data in hopes of providing important context to these national estimates of cirrhosis burden.

RESULTS

An estimated 1.5 billion persons have CLD worldwide and the age-standardized incidence of CLD and cirrhosis is 20.7/100,000, a 13% increase since 2000. Similarly, cirrhosis prevalence and mortality has increased in recent years in the United States. The epidemiology of CLD is shifting, reflecting implementation of large-scale hepatitis B vaccination and hepatitis C treatment programs, the increasing prevalence of the metabolic syndrome, and increasing alcohol misuse.

CONCLUSIONS

The global burden of CLD and cirrhosis is substantial. Although vaccination, screening, and antiviral treatment campaigns for hepatitis B and C have reduced the CLD burden in some parts of the world, concomitant increases in injection drug use, alcohol misuse, and metabolic syndrome threaten these trends. Ongoing efforts to address CLD-related morbidity and mortality require accurate contemporary estimates of epidemiology and outcomes.

Effects of Primary Sclerosing Cholangitis on Risks of Cancer and Death in People With Inflammatory Bowel Disease, Based on Sex, Race, and Age

BACKGROUND & AIMS

There are insufficient population-level data on the effects of primary sclerosing cholangitis (PSC) in patients with inflammatory bowel disease (IBD).

METHODS

We identified incident cases of IBD, with PSC (PSC-IBD) and without, from April 2006 to April 2016 and collected data on outcomes through April 2019. We linked data from national health care registries maintained for all adults in England on hospital attendances, imaging and endoscopic evaluations, surgical procedures, cancer, and deaths. Our primary aim was to quantify the effects of developing PSC in patients with all subtypes of IBD and evaluate its effects on hepatopancreatobiliary disease, IBD-related outcomes, and all-cause mortality, according to sex, race, and age.

RESULTS

Over 10 years, we identified 284,560 incident cases of IBD nationwide; of these, 2588 patients developed PSC. In all, we captured 31,587 colectomies, 5608 colorectal cancers (CRCs) 6608 cholecystectomies, and 41,055 patient deaths. Development of PSC was associated with increased risk of death and CRC (hazard ratios [HRs], 3.20 and 2.43, respectively; P < .001) and a lower median age at CRC diagnosis (59 y vs 69 y without PSC; P < .001). Compared to patients with IBD alone, patients with PSC-IBD had a 4-fold higher risk of CRC if they received a diagnosis of IBD at an age younger than 40 years; there was no difference between groups for patients diagnosed with IBD at an age older than 60 years. Development of PSC also increased risks of cholangiocarcinoma (HR, 28.46), hepatocellular carcinoma (HR, 21.00), pancreatic cancer (HR, 5.26), and gallbladder cancer (HR, 9.19) (P < .001 for all). Risk of hepatopancreatobiliary cancer-related death was lower among patients with PSC-IBD who received annual imaging evaluations before their cancer diagnosis, compared to those who did not undergo imaging (HR, 0.43; P = .037). The greatest difference in mortality between the PSC-IBD alone group vs the IBD alone group was for patients younger than 40 years (incidence rate ratio >7), in contrast to those who received a diagnosis of IBD when older than 60 years (incidence rate ratio, <1.5). Among patients with PSC-IBD we observed 173 first liver transplants. Liver transplantation and PSC-related events accounted for approximately 75% of clinical events when patients received a diagnosis of PSC at an age younger than 40 years vs 31% of patients who received a diagnosis when older than 60 years (P < .001). African Caribbean heritage was associated with increased risks of liver transplantation or PSC-related death compared with white race (HR, 2.05; P < .001), whereas female sex was associated with reduced risk (HR, 0.74; P = .025).

CONCLUSIONS

In a 10-year, nationwide study, we confirmed that patients with PSC-IBD have increased risks of CRC, hepatopancreatobiliary cancers, and death compared to patients with IBD alone. In the PSC-IBD group, diagnosis of IBD at age younger than 40 years was associated with greater risks of CRC and all-cause mortality compared with diagnosis of IBD at older ages. Patients who receive a diagnosis of PSC at an age younger than 40 years, men, and patients of African Caribbean heritage have an increased incidence of PSC-related events.

An update on primary sclerosing cholangitis epidemiology, outcomes and quantification of alkaline phosphatase variability in a population-based cohort

BACKGROUND

Contemporary primary sclerosing cholangitis (PSC) population-based cohorts describing the epidemiology, natural history, and long-term fluctuations in serum alkaline phosphatase (SAP) and their prognostic relevance are lacking. Therefore, we investigated the incidence and natural history of PSC and quantified SAP fluctuations among those with PSC in Olmsted County, Minnesota over the last 41 years.

METHODS

The Rochester Epidemiology Project was used to identify 56 subjects diagnosed with PSC between 1976 and 2017 in Olmsted County. The primary endpoint (n = 19) included liver transplantation, hepatic decompensation, and cholangiocarcinoma.

RESULTS

The age- and sex-adjusted incidence of PSC (per 100,000 person years) nearly doubled from 2001 to 2017 compared to 1976-2000 (1.47; 95% CI 0.99-1.96 versus 0.79; 95% CI 0.42-1.16, p = 0.02). This increase paralleled a rise in patients with markers of a milder phenotype at the time of diagnosis: normal SAP (26.32% versus 0%, p < 0.01) and lower Mayo PSC risk score [0.36 (- 0.57 to 1.55) versus - 0.50 (- 1.25 to 0.35), p = 0.03]. Intra-individual SAP fluctuates with a median coefficient of variation of 36.20%. SAP normalization and dropping below 1.5 × upper limit of normal (ULN) occurs at a rate of 5% and 10% per year, respectively. SAP less than 1.5 × ULN was associated with a lower risk of PSC-related complications (hazard ratio 0.11; 95% CI 0.03-0.42).

CONCLUSIONS

The patients with PSC are increasingly being diagnosed with a milder phenotype. While a lower SAP is associated with improved outcomes, the high intra-individual variation of SAP levels calls into question the practice of using a single SAP value as a surrogate endpoint in clinical trials.

Primary Sclerosing Cholangitis: Burden of Disease and Mortality Using Data from the National Rare Diseases Registry in Italy

Introduction: Studies on the epidemiology of primary sclerosing cholangitis (PSC) are mainly based on tertiary referral centers; and are retrospective case series susceptible to selection bias. The aim of this study was to estimate incidence; survival and cause of mortality of PSC in Italy; using population-based data. Methods: Data collected from the National Rare Diseases Registry (RNMR) and the National Mortality Database (NMD) were integrated and analyzed. Results: We identified 502 PSC incident cases. The crude incidence rate between 2012 and 2014 was 0.10 per 100,000 individuals. Sixty percent were male; mean age at disease onset and at diagnosis were 33 and 37 years; respectively; highlighting a mean diagnostic delay of 4 years. The rate of interregional mobility was 12%. Ten-year survival was 92%. In 32% of cases the cause of death was biliary-related; 12% died of biliary or gallbladder cancer. Conclusions: For rare diseases such as PSC; population-based cohort’s studies are of paramount importance. Incidence rates of PSC in Italy are markedly lower and survival much longer than the ones reported from tertiary; single-centre series. Moreover; the diagnostic delay and the patient interregional mobility highlights the need for increasing awareness on the disease and for resource reallocation among Italian regions within the National Health Service

Small Duct Primary Sclerosing Cholangitis: An Underdiagnosed Cause of Chronic Liver Disease and Cirrhosis

Classic or large duct primary sclerosing cholangitis (PSC) is part of the PSC spectrum. It is diagnosed on clinical and biochemical findings of cholestasis supported by biliary tree changes on cholangiography, forgoing the need for an invasive liver biopsy. The spectrum contains various PSC variants with distinct clinical courses and outcomes. We present a case of small duct PSC, a rare variant that manifested insidiously with clinical and objective cholestasis but appeared negative on diagnostic cholangiography. Eventually, a liver biopsy was obtained that revealed chronic bilious disease of the small and microscopic ducts with simultaneous changes consistent with liver cirrhosis. Despite presenting like its classical counterpart, small duct PSC can remain undetectable on cholangiography due to the diminutive size of the bile ducts requiring histological confirmation. In contrast to classic PSC, small duct PSC portends a much better prognosis. However, it eventually progresses to the classic form or end-stage liver disease, requiring patients to receive timely surveillance and transplantation referrals. Due to the limited understanding of this disease process, patients with similar presentations often pose a diagnostic dilemma due to the clinical and cholangiographic mismatch. This case aims to reaffirm that a negative cholangiography does not rule out the PSC spectrum and that small duct disease is a rare but growing entity. The paucity in cases emphasizes the importance of isolated reports in guiding workup and management, especially since surveillance schedules and transplantation guidelines have not been formally established.

IgG4-Related Sclerosing Cholangitis and Primary Sclerosing Cholangitis

Sclerosing cholangitis (SC) is defined as a condition with progressive stenosis and destruction of the bile ducts due to diffuse inflammation and fibrosis and currently includes three categories: primary sclerosing cholangitis (PSC), secondary cholangitis, and IgG4-related sclerosing cholangitis (IgG4-SC). SC categories share similar clinical features, such as cholestasis. Patients with SC present with cholestatic symptoms, including jaundice and pruritus, and blood tests reveal elevation of cholestatic enzymes. Cholangiography, endoscopic or magnetic, is inevitably required for making a diagnosis. Although the presentation of IgG4-SC and PSC are similar, the comorbidities, treatment response, and outcomes differ significantly, and therefore, it is strongly advisable to be familiar with these two diseases to make a correct diagnosis. Differentiation of cholangiocarcinoma from IgG4-SC and PSC is also extremely important. In this review, the clinical characteristics, comorbidities, treatment and outcomes of IgG4-SC and PSC will be outlined based on experience mainly from Japan.