Prevalence of Primary Sclerosing Cholangitis in Patients With Inflammatory Bowel Disease: A Systematic Review and Meta-analysis

Targeting the Endocannabinoidome: A Novel Approach to Managing Extraintestinal Complications in Inflammatory Bowel Disease

Background: Inflammatory bowel disease (IBD) is a chronic inflammatory disorder marked by persistent gastrointestinal inflammation and a spectrum of systemic effects, including extraintestinal manifestations (EIMs) that impact the joints, skin, liver, and eyes. Conventional therapies primarily target intestinal inflammation, yet they frequently fail to ameliorate these systemic complications. Recent investigations have highlighted the complex interplay among the immune system, gut, and nervous system in IBD pathogenesis, thereby underscoring the need for innovative therapeutic approaches. Methods: We conducted a comprehensive literature search using databases such as PubMed, Scopus, Web of Science, Science Direct, and Google Scholar. Keywords including "cannabinoids", "endocannabinoid system", "endocannabinoidome", "inflammatory bowel disease", and "extraintestinal manifestations" were used to identify peer-reviewed original research and review articles that explore the role of the endocannabinoidome (eCBome) in IBD. Results: Emerging evidence suggests that eCBome-a network comprising lipid mediators, receptors (e.g., CB1, CB2, GPR55, GPR35, PPARα, TRPV1), and metabolic enzymes-plays a critical role in modulating immune responses, maintaining gut barrier integrity, and regulating systemic inflammation. Targeting eCBome not only improves intestinal inflammation but also appears to mitigate metabolic, neurological, and extraintestinal complications such as arthritis, liver dysfunction, and dermatological disorders. Conclusions: Modulation of eCBome represents a promising strategy for comprehensive IBD management by addressing both local and systemic disease components. These findings advocate for further mechanistic studies to develop targeted interventions that leverage eCBome as a novel therapeutic avenue in IBD.

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.

Primary sclerosing cholangitis-inflammatory bowel disease: Epidemiology, mortality, and impact of diagnostic sequence

Background & Aims

Primary sclerosing cholangitis (PSC) carries significant morbidity and mortality compared with inflammatory bowel disease (IBD). We characterized epidemiology trends and outcomes in those with PSC-IBD and IBD, paying particular attention to the impact of PSC-IBD diagnostic sequence on outcomes.

Methods

Incidence and prevalence of PSC-IBD and IBD (2002-2018) were evaluated using validated health administrative data-derived cohorts from Ontario, Canada (population ∼15 million). Transplant and death outcomes were assessed, with PSC-IBD diagnostic sequence as the exposure of interest.

Results

Incidence of PSC-IBD and IBD was 0.46 and 24.6/100,000 person-years (PYs) respectively, whereas prevalence was 5.53 and 588/100,000 PY respectively. Incidence/prevalence of PSC-IBD increased over time, unlike for IBD. Age at IBD diagnosis was earlier among those with PSC-IBD compared with those with IBD alone. Higher socioeconomic status associated with high PSC-IBD incidence rates and fastest incidence rise. Those diagnosed with IBD before PSC had higher risk of transplant/death compared with PSC before IBD (hazard ratio [HR] 1.34, 95% CI 1.02-1.75), driven by an increased risk of death (HR 2.73, 95% CI 1.68-4.45). PSC-IBD had a 4.5-fold greater risk of transplant/death compared with IBD alone. Liver-related and luminal gastrointestinal disease, particularly hepatopancreatobiliary malignancy, were predominant causes of death among those with PSC-IBD, while cardiovascular and respiratory diseases were predominant among those with IBD.

Conclusions

Population-level data support distinct epidemiological patterns among people living with PSC-IBD compared with IBD, including a higher socioeconomic status and worse outcomes in those found to have IBD before PSC.

Impact and implications

Individuals with primary sclerosing cholangitis (PSC) face increased morbidity and mortality compared with the general population and those with inflammatory bowel disease (IBD); yet, most individuals with PSC are found to have concomitant IBD during their lifetime. This study describes the distinctive epidemiological differences and mortality trends at the population level between PSC-IBD and IBD. While PSC-IBD remains a rare condition, diagnoses are on the rise (particularly among higher socioeconomic status populations), with most patients being diagnosed with IBD before PSC; this group also experienced higher mortality post-PSC diagnosis compared with those diagnosed with PSC first, with a large proportion of deaths caused by liver- and gut-related causes. Practical applications of these findings include further studies to evaluate whether earlier identification of PSC-IBD affects disease outcomes, as well as educating patients, clinicians, and policymakers on the importance of recognizing PSC-IBD as a distinct entity from IBD alone.

Liver diseases: epidemiology, causes, trends and predictions

As a highly complex organ with digestive, endocrine, and immune-regulatory functions, the liver is pivotal in maintaining physiological homeostasis through its roles in metabolism, detoxification, and immune response. Various factors including viruses, alcohol, metabolites, toxins, and other pathogenic agents can compromise liver function, leading to acute or chronic injury that may progress to end-stage liver diseases. While sharing common features, liver diseases exhibit distinct pathophysiological, clinical, and therapeutic profiles. Currently, liver diseases contribute to approximately 2 million deaths globally each year, imposing significant economic and social burdens worldwide. However, there is no cure for many kinds of liver diseases, partly due to a lack of thorough understanding of the development of these liver diseases. Therefore, this review provides a comprehensive examination of the epidemiology and characteristics of liver diseases, covering a spectrum from acute and chronic conditions to end-stage manifestations. We also highlight the multifaceted mechanisms underlying the initiation and progression of liver diseases, spanning molecular and cellular levels to organ networks. Additionally, this review offers updates on innovative diagnostic techniques, current treatments, and potential therapeutic targets presently under clinical evaluation. Recent advances in understanding the pathogenesis of liver diseases hold critical implications and translational value for the development of novel therapeutic strategies.

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.

Hepatobiliary and pancreatic manifestations in inflammatory bowel disease: an umbrella review of meta-analyses

Background

Inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn's disease (CD), can affect the hepatobiliary system and pancreas, substantially impacting the life quality of patients.

Objectives

To evaluate the quality of evidence and comprehensively assess the validity of associations of IBD with hepatobiliary and pancreatic diseases.

Design

We performed an umbrella review of existing meta-analyses in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) recommendations.

Data sources and methods

We systematically searched PubMed, Embase, and Web of Science from inception to April 2024, to identify and appraise meta-analyses examining IBD and risk of hepatobiliary and pancreatic manifestations. Methodologic quality was assessed with A Measurement Tool to Assess Systematic Reviews (AMSTAR 2) and the strength of evidence was graded according to prespecified criteria.

Results

A total of 14 meta-analyses of observational studies were included. The strongest-validity evidence suggested the significant associations between IBD and risk of gallstones (odds ratio (OR) = 1.72; 95% confidence interval (CI) = 1.40-2.12) and acute pancreatitis (OR = 3.11; 95% CI = 2.93-3.30). Highly suggestive evidence indicated a significantly increased risk of hepatobiliary cancer in UC (incidence rate ratio (IRR) = 2.05; 95% CI = 1.52-2.76) and CD (IRR = 2.31; 95% CI = 1.25-4.28). In addition, highly suggestive evidence indicated that IBD was associated with portal venous system thrombosis. Suggestive evidence showed a significantly higher prevalence of primary sclerosing cholangitis, non-alcoholic fatty liver disease, autoimmune hepatitis, and autoimmune pancreatitis in IBD patients than in the general population.

Conclusion

The associations between IBD and multiple hepatobiliary and pancreatic disorders showed varying levels of evidence and magnitude of risk. Further high-quality primary studies are needed to identify IBD patients who are more at risk and would benefit the most from screening and prevention programs.

Trial registration PROSPERO

CRD42023451461.

Suboptimal disease control and contributing factors in Italian IBD patients: The IBD-PODCAST Study

BACKGROUND AND AIM

Suboptimal disease control (SDC) and its contributing factors in IBD according to STRIDE-II criteria is unclear. IBD-PODCAST was a non-interventional, international, multicenter real-world study to assess this.

METHODS

Data from the Italian IBD cohort (N=220) are presented here. Participants aged ≥19 with confirmed IBD diagnosis of ≥1 year were consecutively enrolled. A retrospective chart review and cross-sectional assessment by physicians and patients within the past 12 months were performed. SDC or optimal disease control was assessed using adapted STRIDE-II criteria.

RESULTS

At the index date, 53.4 % of 116 CD patients and 49.0 % of 104 UC patients had SDC, mainly attributed to a Short Inflammatory Bowel Disease Questionnaire score <50, failure to achieve endoscopic remission, and the presence of active extra-intestinal manifestations in both diseases. Disease monitoring with imaging and/or endoscopy during the previous year was conducted in ∼50 % of patients, with endoscopy performed in ∼40 %. Potential therapeutic adjustments were reported for half of the patients.

CONCLUSIONS

This study highlights SDC in a significant portion of IBD Italian patients. These results emphasize the need for more proactive management strategies in both CD and UC patients.

Primary Biliary Cholangitis Associated with Ulcerative Colitis: Case Series and Literature Review

Purpose: To study the coexistence of ulcerative colitis (UC) and primary biliary cholangitis (PBC). Methods: The Beijing Friendship Hospital patient database was explored to identify patients presenting both UC and PBC from January 2015 to July 2024. By a review of the literature, the characteristics of UC patients who experienced PBC was summarized. Results: We identified 890 UC patients and reported 4 individuals who suffered from UC and PBC. Compared to the general population, UC patients seem to have a higher risk of PBC. Only 28 cases of UC with PBC have been reported so far. Most patients were diagnosed with UC prior to PBC. Once UC patients are complicated with PBC, they might experience more than one extraintestinal manifestation (EIM). Shared susceptibility genes, certain bacterial infections, and common immune-mediated mechanisms may be involved in the pathogenesis of UC patients with PBC. Conclusions: Although the coexistence of UC and PBC is uncommon, PBC should be considered in UC patients with hepatobiliary disorders.

The mediating role of primary sclerosing cholangitis in the association between ulcerative colitis and hepatobiliary cancer investigated through Mendelian randomization

This study explored the causal relationships among primary sclerosing cholangitis (PSC), ulcerative colitis (UC), and hepatobiliary cancer (HBC) by using bidirectional two-sample, two-step Mendelian randomization (MR) analysis. Genetic variants associated with PSC and UC from the FinnGen research database were used for instrumental variable-based analyses. Mediation analyses were conducted to examine the role of PSC and UC in HBC risk. The findings revealed a causal effect of genetic predisposition to UC on PSC risk (inverse-variance-weighted [IVW] analysis odds ratio [OR] 1.145, p < 0.001), whereas no reverse causality was observed. Although UC showed no direct causal effect on HBC risk, genetic susceptibility to PSC significantly increased the risk of HBC (IVW analysis OR = 1.855, p < 0.001). Mediation analysis further identified PSC as a significant mediator amplifying the causal effect of UC on HBC risk (effect size = 0.083). These results established a causal link between genetic susceptibility to UC and increased risk of PSC, and highlighted the critical role of PSC in mediating the impact of UC on HBC risk.

Advancing therapeutic frontiers: a pipeline of novel drugs for luminal and perianal Crohn's disease management

Crohn's disease (CD) is a chronic, complex inflammatory disorder of the gastrointestinal tract that presents significant therapeutic challenges. Despite the availability of a wide range of treatments, many patients experience primary non-response, secondary loss of response, or adverse events, limiting the overall effectiveness of current therapies. Clinical trials often report response rates below 60%, partly due to stringent inclusion criteria. Emerging therapies that target novel pathways offer promise in overcoming these limitations. This review explores the latest investigational drugs in phases I, II, and III clinical trials for treating both luminal and perianal CD. We highlight promising therapies that target known mechanisms, including selective Janus kinase inhibitors, anti-adhesion molecules, tumor necrosis factor inhibitors, and IL-23 selective inhibitors. In addition, we delve into novel therapeutic strategies such as sphingosine-1-phosphate receptor modulators, miR-124 upregulators, anti-fractalkine (CX3CL1), anti-TL1A, peroxisome proliferator-activated receptor gamma agonists, TGFBRI/ALK5 inhibitors, anti-CCR9 agents, and other innovative small molecules, as well as combination therapies. These emerging approaches, by addressing new pathways and mechanisms of action, have the potential to surpass the limitations of existing treatments and significantly improve CD management. However, the path to developing new therapies for inflammatory bowel disease (IBD) is fraught with challenges, including complex trial designs, ethical concerns regarding placebo use, recruitment difficulties, and escalating costs. The landscape of IBD clinical trials is shifting toward greater inclusivity, improved patient diversity, and innovative trial designs, such as adaptive and Bayesian approaches, to address these challenges. By overcoming these obstacles, the drug development pipeline can advance more effective, accessible, and timely treatments for CD.

Molecular Mechanisms of Fibrosis in Cholestatic Liver Diseases and Regenerative Medicine-Based Therapies

The aim of this review is to explore the potential of new regenerative medicine approaches in the treatment of cholestatic liver fibrosis. Cholestatic liver diseases, such as primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC), and biliary atresia (BA), due to the accumulation of bile, often progress to liver fibrosis, cirrhosis, and liver failure. When the disease becomes severe enough to require liver transplantation. Deeply understanding the disease's progression and fibrosis formation is crucial for better diagnosis and treatment. Current liver fibrosis treatments mainly target the root causes and no direct treatment method in fibrosis itself. Recent advances in regenerative medicine offer a potential approach that may help find the ways to target fibrosis directly, offering hope for improved outcomes. We also summarize, analyze, and discuss the current state and benefits of regenerative medicine therapies such as mesenchymal stem cell (MSC) therapy, induced pluripotent stem cells (iPSCs), and organoid technology, which may help the treatment of cholestatic liver diseases. Focusing on the latest research may reveal new targets and enhance therapeutic efficacy, potentially leading to more effective management and even curative strategies for cholestatic liver diseases.

Hepatic immune regulation and sex disparities

Chronic liver disease is a major cause of morbidity and mortality worldwide. Epidemiology, clinical phenotype and response to therapies for gastrointestinal and liver diseases are commonly different between women and men due to sex-specific hormonal, genetic and immune-related factors. The hepatic immune system has unique regulatory functions that promote the induction of intrahepatic tolerance, which is key for maintaining liver health and homeostasis. In liver diseases, hepatic immune alterations are increasingly recognized as a main cofactor responsible for the development and progression of chronic liver injury and fibrosis. In this Review, we discuss the basic mechanisms of sex disparity in hepatic immune regulation and how these mechanisms influence and modify the development of autoimmune liver diseases, genetic liver diseases, portal hypertension and inflammation in chronic liver disease. Alterations in gut microbiota and their crosstalk with the hepatic immune system might affect the progression of liver disease in a sex-specific manner, creating potential opportunities for novel diagnostic and therapeutic approaches to be evaluated in clinical trials. Finally, we identify and propose areas for future basic, translational and clinical research that will advance our understanding of sex disparities in hepatic immunity and liver disease.

Total Proctocolectomy vs Subtotal/total Colectomy for Neoplasia in Patients With Inflammatory Bowel Disease and Primary Sclerosing Cholangitis

BACKGROUND

Patients with inflammatory bowel disease (IBD) and primary sclerosing cholangitis (PSC) frequently undergo restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) for medically refractory disease or colonic dysplasia/neoplasia. Subtotal colectomy with ileosigmoid or ileorectal anastomosis may have improved outcomes but is not well studied. Due to increased risk for colorectal cancer in PSC-IBD, there is hesitancy to perform subtotal colectomy. We aim to describe the frequency of colorectal dysplasia/neoplasia following IPAA vs subtotal colectomy in PSC-IBD patients.

METHODS

We completed a retrospective study from 1972 to 2022 of patients with PSC-IBD who had undergone total proctocolectomy with IPAA or subtotal colectomy. We abstracted demographics, disease characteristics, and endoscopic surveillance data from the EMR.

RESULTS

Of 125 patients (99 IPAA; 26 subtotal), the indication for surgery was rectal sparing medically refractory disease (51% vs 42%), dysplasia (37% vs 30%) and neoplasia (11% vs 26%) in IPAA vs subtotal colectomy patients, respectively. On endoscopic surveillance of IPAA patients, 2 (2%) had low-grade dysplasia (LGD) in the ileal pouch and 2 (2%) had LGD in the rectal cuff after an average of 8.4 years and 12.3 years of follow-up, respectively. One (1%) IPAA patient developed neoplasia of the rectal cuff after 17.8 years of surgical continuity. No subtotal colectomy patients had dysplasia/neoplasia in the residual colon or rectum.

CONCLUSIONS

In patients with PSC-IBD, there was no dysplasia or neoplasia in those who underwent subtotal colectomy as opposed to the IPAA group. Subtotal colectomy may be considered a viable surgical option in patients with rectal sparing PSC-IBD if adequate endoscopic surveillance is implemented.

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.

Outcome of Very Early Onset Inflammatory Bowel Disease Associated With Primary Sclerosing Cholangitis: A Multicenter Study From the Pediatric IBD Porto Group of ESPGHAN

BACKGROUND

Whether primary sclerosing cholangitis related to inflammatory bowel disease (PSC-IBD) diagnosed before 6 years (ie, VEO-IBD) has a distinct phenotype and disease course is uninvestigated. We aimed to analyze the characteristics and natural history of VEO-PSC-IBD, compared with early and adolescent-onset PSC-IBD.

METHODS

This is a multicenter, retrospective, case-control study from 15 centers affiliated with the Porto and Interest IBD group of ESPGHAN. Demographic, clinical, laboratory, endoscopic, and imaging data were collected at baseline and every 6 months. Inflammatory bowel disease-related (clinical remission, need for systemic steroids and biologics, and surgery) and PSC-related (biliary and portal hypertensive complications, need for treatment escalation and liver transplantation, cholangiocarcinoma, or death) outcomes were compared between the 2 groups.

RESULTS

Sixty-nine children were included, with a median follow-up of 3.63 years (interquartile range, 1-11): 28 with VEO-PSC-IBD (23 UC [82%], 2 IBD-U [7%] and 3 [11%] CD), and 41 with PSC-IBD (37 UC [90%], 3 IBDU [7.5%] and 1 [2.5%] CD). Most patients with UC presented with pancolitis (92% in VEO-PSC-UC vs 85% in PSC-UC, P = .2). A higher number of patients with VEO-PSC-IBD were diagnosed with PSC/autoimmune hepatitis overlap syndrome than older children (24 [92%] vs 27 [67.5%] PSC-IBD, P = .03), whereas no other differences were found for PSC-related variables. Time to biliary strictures and infective cholangitis was lower in the VEO-PSC-IBD group (P = .01 and P = .04, respectively), while no difference was found for other outcomes. No cases of cholangiocarcinoma were reported.

CONCLUSIONS

Primary sclerosing cholangitis related to inflammatory bowel disease has similar baseline characteristics whether diagnosed as VEO-IBD or thereafter. A milder disease course in terms of biliary complications characterizes VEO-PSC-IBD.

Increased Active Inflammation in the Colon is Not a Reliable Predictor of an Elevated Risk of Dysplasia in Patients With Primary Sclerosing Cholangitis and Ulcerative Colitis

Although the increased risk of colorectal neoplasia in patients with both primary sclerosing cholangitis (PSC) and ulcerative colitis (UC; termed PSC-UC) is well documented, the mechanism through which concomitant PSC increases the risk of colorectal neoplasia remains unclear. Given that the risk of colorectal neoplasia in UC is positively correlated with increased histologic inflammation, this study sought to investigate whether increased histologic inflammation could be used to stratify the risk of dysplasia development in patients with PSC-UC. Twenty patients with PSC-UC and dysplasia were compared with 30 control patients with PSC-UC who had no history of neoplasia. For each patient, all surveillance biopsies were scored using a 4-point scoring system: (1) no epithelial neutrophils = 0, (2) cryptitis only = 1, (3) cryptitis plus crypt abscess in <50% of crypts = 2, and (4) crypt abscess in ≥50% of crypts, erosion, neutrophilic exudate, and/or ulceration = 3. A score was designated for each biopsy, and both mean and maximum inflammation scores were calculated from all biopsies taken during each colonoscopy. The inflammation burden score was calculated for each surveillance interval by multiplying the average maximum score between each pair of surveillance episodes by the length of the surveillance interval in years. The average scores derived from all colonoscopies for each patient were used to determine the patient's overall mean, maximum, and inflammation burden scores. In both the dysplasia and control groups, the 3 summative inflammation scores were calculated independently for the entire colon, right colon, and left colon. The dysplasia group consisted of 14 (70%) men and 6 (30%) women, with a mean age of 27 years at UC diagnosis and a long history of pancolitis (mean duration: 17 y). A total of 49 dysplastic lesions were detected in the dysplasia group, and 8 (40%) of the 20 patients had multifocal dysplasia. The majority of dysplastic lesions belonged to nonconventional subtypes (n = 28; 57%) and were located in the right colon (n = 37; 76%). Irrespective of the colon segment, there was no significant difference in the 3 summative inflammation scores between the dysplasia and control groups ( P > 0.05). However, in each group, the 3 summative inflammation scores were significantly higher in the right colon than in the left colon ( P < 0.05). In conclusion, patients with PSC-UC exhibit increased histologic inflammation in the right colon compared with the left colon, regardless of the presence of dysplasia. Although this may provide an explanation for the predominance of right-sided colorectal neoplasia in patients with PSC-UC, increased histologic inflammation does not reliably predict an elevated risk of dysplasia in patients with PSC-UC. These findings reinforce the current recommendation for annual endoscopic surveillance for all patients with PSC-UC, irrespective of the extent and severity of inflammation.

Risk of comorbidity of autoimmune liver disease in patients with inflammatory bowel disease: A single-center case-control study in China

OBJECTIVE

To investigate the prevalence of autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), and primary sclerosing cholangitis (PSC), and the impact of comorbidity of AIH, PBC, and PSC on hospitalization burden in patients with inflammatory bowel disease (IBD).

METHODS

Inpatients admitted to Peking Union Medical College Hospital from January 1, 1998 to December 31, 2021 were included. Odds ratio (OR) and the corresponding 95% confidence interval (CI) were calculated to compare the risk of AIH, PBC, and PSC between IBD and non-IBD patients. Medical cost and length of hospitalization were compared between IBD patients with and without AIH, PBC, or PSC.

RESULTS

Among the included 858 967 inpatients, there were 3059 patients with IBD. Additionally, there were 117 patients with AIH, 879 patients with PBC, and 35 patients with PSC, regardless of having IBD or not. Patients with IBD had a significantly higher risk of AIH (OR 4.87, 95% CI 1.20-19.71, p = 0.03) and PSC (OR 112.28, 95% CI 53.88-233.98, p < 0.01) than those without IBD. While there was no significant difference in the risk of PBC between patients with and without IBD (OR 1.60, 95% CI 0.67-3.86, p = 0.29). The medical cost of each hospitalization did not differ between IBD patients with and without AIH, PBC, or PSC.

CONCLUSIONS

IBD patients had a higher risk of AIH and PSC. Comorbidity of AIH, PBC, or PSC has no significant effect on the average cost of each hospitalization in IBD patients.

Hereditary Colorectal Cancer Syndromes and Inflammatory Bowel Diseases: Risk Management and Surveillance Strategies

Background and aims: Hereditary colorectal cancer syndromes (HCCS), including familial adenomatous polyposis (FAP) and Lynch syndrome (LS), are the two most important high-risk conditions for colorectal cancer (CRC). Inflammatory bowel disease (IBD) increases the risk by two to six times compared with that in the general population. The intersection of these two conditions has rarely been documented in literature. We aimed to summarize the prevalence, pathogenesis, and current evidence-based management of IBD and HCCS and the underlying molecular mechanisms of accelerated carcinogenesis due to combined inflammation and genetic predisposition. Methods: PubMed and Scopus were searched until June 2024 to identify relevant studies investigating the epidemiology, pathogenesis, and management of IBD and coexisting hereditary CRC syndromes. Results: Co-occurrence of IBD and hereditary CRC syndromes is exceptionally uncommon. Individuals with LS and IBD tend to develop CRC at a younger age than those without IBD, with patients with ulcerative colitis facing particularly elevated risks. The interaction between mismatch deficiency and chronic inflammation requires further investigation.

Extraintestinal Manifestations in Inflammatory Bowel Disease: From Pathophysiology to Treatment

The inflammatory bowel diseases (IBDs) are systemic conditions that affect not only the gastrointestinal tract but also other parts of the body. The presence of extraintestinal manifestations can significantly impact the quality of life in IBD patients. Peripheral arthritis, episcleritis, and erythema nodosum are frequently associated with active intestinal inflammation and often improve with standard treatment targeting intestinal inflammation. In contrast, anterior uveitis, ankylosing spondylitis, and primary sclerosing cholangitis typically occur independently of disease flares. The incidence of these conditions in individuals with IBD can reach up to 50% of patients over the course of their lifetime. In addition, some advanced therapies utilized for the treatment of IBD potentially result in side effects that may resemble extraintestinal manifestations. This review provides a thorough analysis of the pathophysiology and treatment of extraintestinal manifestations associated with Crohn's disease and ulcerative colitis.

Causality of genetically determined blood metabolites on inflammatory bowel disease: a two-sample Mendelian randomization study

Inflammatory bowel disease (IBD) is a chronic and recurrent inflammatory disease of the gastrointestinal tract, including two subtypes: Crohn's disease (CD) and ulcerative colitis (UC). Metabolic disorders are important factors in the development of IBD. However, the evidence for the causal relationship between blood metabolites and IBD remains limited. A two-sample MR analysis was applied to evaluate relationships between 486 blood metabolites and IBD. The inverse variance weighted method was chosen as the primary MR analysis method. False discovery rate correction was used to control for false positives in multiple testing. Following complementary and sensitivity analyses were conducted using methods such as weight median, MR-egger, weighted mode, simple mode, Cochran Q test, and MR-PRESSO. Moreover, we performed replication, meta-analysis, Steiger test, and linkage disequilibrium score regression to enhance the robustness of the results. Additionally, we performed metabolic pathway analysis to identify potential metabolic pathways. As a result, we identified four significant causal associations between four blood metabolites and two IBD subtypes. Specifically, one metabolite was identified as being associated with the development of CD (mannose: odds ratio (OR) = 0.19, 95% confidence interval (CI) 0.08-0.43, P = 8.54 × 10-5). Three metabolites were identified as being associated with the development of UC (arachidonate (20:4n6): OR = 0.18, 95% CI 0.11-0.30, P = 2.09 × 10-11; 1, 5-anhydroglucitol: OR = 2.21, 95% CI 1.47-3.34, P = 1.50 × 10-4; 2-stearoylglycerophosphocholine: OR = 2.66, 95% CI 1.53-4.63, P = 5.30 × 10-4). The findings of our study suggested that the identified metabolites and metabolic pathways can be considered as useful circulating metabolic biomarkers for the screening and prevention of IBD in clinical practice, as well as candidate molecules for future mechanism exploration and drug target selection.

Challenges in IBD Research 2024: Precision Medicine

Precision medicine is part of 5 focus areas of the Challenges in IBD Research 2024 research document, which also includes preclinical human IBD mechanisms, environmental triggers, novel technologies, and pragmatic clinical research. Building on Challenges in IBD Research 2019, the current Challenges aims to provide a comprehensive overview of current gaps in inflammatory bowel diseases (IBDs) research and deliver actionable approaches to address them with a focus on how these gaps can lead to advancements in interception, remission, and restoration for these diseases. The document is the result of multidisciplinary input from scientists, clinicians, patients, and funders, and represents a valuable resource for patient-centric research prioritization. In particular, the precision medicine section is focused on the main research gaps in elucidating how to bring the best care to the individual patient in IBD. Research gaps were identified in biomarker discovery and validation for predicting disease progression and choosing the most appropriate treatment for each patient. Other gaps were identified in making the best use of existing patient biosamples and clinical data, developing new technologies to analyze large datasets, and overcoming regulatory and payer hurdles to enable clinical use of biomarkers. To address these gaps, the Workgroup suggests focusing on thoroughly validating existing candidate biomarkers, using best-in-class data generation and analysis tools, and establishing cross-disciplinary teams to tackle regulatory hurdles as early as possible. Altogether, the precision medicine group recognizes the importance of bringing basic scientific biomarker discovery and translating it into the clinic to help improve the lives of IBD patients.

Dissecting causal relationships between primary biliary cholangitis and extrahepatic autoimmune diseases based on Mendelian randomization

As an autoimmune disease, up to 73% of patients with primary biliary cholangitis (PBC) have a combination of extrahepatic autoimmune diseases (EHAIDs); however, the causal relationship between PBC and EHAIDs is unclear. The genome-wide association analyses provided 14 GWAS data for PBC and EHAIDs, and bidirectional, two-sample MR analyses were performed to examine the relationship between PBC and EHAIDs. The analysis using MR provides a strong and meaningful estimation of the bidirectional correlation between PBC and 7 EHAIDs: rheumatoid arthritis, systemic lupus erythematosus, Sjögren's syndrome, systemic sclerosis, autoimmune hypothyroidism, inflammatory bowel disease and ulcerative colitis of its types. In addition, PBC increases the risk of autoimmune thyroid diseases such as autoimmune hyperthyroidism and Graves' disease, as well as multiple sclerosis and psoriasis. Additionally, PBC is identified as a risk factor for Crohn's disease and Celiac disease. Based on genetic evidence, there may be connections between PBC and specific EHAIDs: not all coexisting EHAIDs induce PBC, and vice versa. This underscores the significance of prioritizing PBC in clinical practice. Additionally, if any liver function abnormalities are observed during treatment or with EHAIDs, it is crucial to consider the possibility of comorbid PBC.

Genetic association and causal relationship between multiple modifiable risk factors and autoimmune liver disease: a two-sample mendelian randomization study

BACKGROUND

The intricate etiology of autoimmune liver disease (AILD) involves genetic, environmental, and other factors that yet to be completely elucidated. This study comprehensively assessed the causal association between genetically predicted modifiable risk factors and AILD by employing Mendelian randomization.

METHODS

Genetic variants associated with 29 exposure factors were obtained from genome-wide association studies (GWAS). Genetic association data with autoimmune hepatitis (AIH), primary biliary cholangitis (PBC) and primary sclerosing cholangitis (PSC) were also obtained from publicly available GWAS. Univariate and multivariate Mendelian randomization analyses were performed to identify potential risk factors for AILD.

RESULTS

Genetically predicted rheumatoid arthritis (RA) (OR = 1.620, 95%CI 1.423-1.843, P = 2.506 × 10- 13) was significantly associated with an increased risk of AIH. Genetically predicted smoking initiation (OR = 1.637, 95%CI 1.055-2.540, P = 0.028), lower coffee intake (OR = 0.359, 95%CI 0.131-0.985, P = 0.047), cholelithiasis (OR = 1.134, 95%CI 1.023-1.257, P = 0.017) and higher C-reactive protein (CRP) (OR = 1.397, 95%CI 1.094-1.784, P = 0.007) were suggestively associated with an increased risk of AIH. Genetically predicted inflammatory bowel disease (IBD) (OR = 1.212, 95%CI 1.127-1.303, P = 2.015 × 10- 7) and RA (OR = 1.417, 95%CI 1.193-1.683, P = 7.193 × 10- 5) were significantly associated with increased risk of PBC. Genetically predicted smoking initiation (OR = 1.167, 95%CI 1.005-1.355, P = 0.043), systemic lupus erythematosus (SLE) (OR = 1.086, 95%CI 1.017-1.160, P = 0.014) and higher CRP (OR = 1.199, 95%CI 1.019-1.410, P = 0.028) were suggestively associated with an increased risk of PBC. Higher vitamin D3 (OR = 0.741, 95%CI 0.560-0.980, P = 0.036) and calcium (OR = 0.834, 95%CI 0.699-0.995, P = 0.044) levels were suggestive protective factors for PBC. Genetically predicted smoking initiation (OR = 0.630, 95%CI 0.462-0.860, P = 0.004) was suggestively associated with a decreased risk of PSC. Genetically predicted IBD (OR = 1.252, 95%CI 1.164-1.346, P = 1.394 × 10- 9), RA (OR = 1.543, 95%CI 1.279-1.861, P = 5.728 × 10- 6) and lower glycosylated hemoglobin (HbA1c) (OR = 0.268, 95%CI 0.141-0.510, P = 6.172 × 10- 5) were positively associated with an increased risk of PSC.

CONCLUSIONS

Evidence on the causal relationship between 29 genetically predicted modifiable risk factors and the risk of AIH, PBC, and PSC is provided by this study. These findings provide fresh perspectives on the management and prevention strategies for AILD.

Are Gender Differences Important for Autoimmune Liver Diseases?

Gender Medicine has had an enormous expansion over the last ten years. Autoimmune liver diseases include several conditions, i.e., autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC), and conditions involving the liver or biliary tree overlapping with AIH, as well as IgG4-related disease. However, little is known about the impact of sex in the pathogenesis and natural history of these conditions. The purpose of this review is to provide an update of the gender disparities among the autoimmune liver diseases by reviewing the data published from 1999 to 2023. The epidemiology of these diseases has been changing over the last years, due to the amelioration of knowledge in their diagnosis, pathogenesis, and treatment. The clinical data collected so far support the existence of sex differences in the natural history of autoimmune liver diseases. Notably, their history could be longer than that which is now known, with problems being initiated even at a pediatric age. Moreover, gender disparity has been observed during the onset of complications related to end-stage liver disease, including cancer incidence. However, there is still an important debate among researchers about the impact of sex and the pathogenesis of these conditions. With this review, we would like to emphasize the urgency of basic science and clinical research to increase our understanding of the sex differences in autoimmune liver diseases.

Gut Microbiota in Primary Sclerosing Cholangitis: From Prognostic Role to Therapeutic Implications

BACKGROUND

Primary sclerosing cholangitis (PSC) is a chronic cholestatic disease of unknown etiology characterized by biliary inflammation and periductal fibrosis. The gut microbiota plays a crucial role in the pathogenesis of PSC by regulating bile acid metabolism, inflammation, and immune response. On the other hand, liver disease progression affects the composition of the gut microbiota, fostering these mechanisms in a mutual detrimental way.

SUMMARY

Recent evidences described a specific pro-inflammatory microbial signature in PSC patients, with an overall reduced bacterial diversity and the loss of beneficial metabolites such as short-chain fatty acids. As effective therapies for PSC are still lacking, targeting the gut microbiota offers a new perspective in the management of this disease. To date, antibiotics, fecal microbiota transplantation, and probiotics are the most studied gut microbiota-targeted intervention in PSC, but new potential strategies such as vaccines and bacteriophages represent possible future therapeutic horizons.

KEY MESSAGES

In this review, we focus on the role of the gut microbiota in PSC, considering its pathogenetic and prognostic role and the therapeutic implications.

Prevalence of Hepatobiliary Manifestations in Inflammatory Bowel Disease: A GRADE Assessed Systematic Review and Meta-Analysis of more than 1.7 Million Patients

BACKGROUND AND AIMS

Inflammatory bowel disease [IBD] comprises an immune-mediated group of chronic gastrointestinal disorders. Patients with IBD may experience extraintestinal manifestations, such as hepatobiliary complications. This meta-analysis aims to assess the prevalence of different hepatic manifestations in IBD patients.

METHODS

For this systematic review and meta-analysis, PubMed, Scopus, Web of Science, and Embase were searched until July 20, 2022, by specifying keywords for IBD, hepatic manifestations, and study type. Full texts of cohort studies in English that examined the prevalence of different hepatic manifestations were included in this study. The primary outcome was the overall prevalence of hepatic manifestations in IBD patients. For the statistical analysis, a proportion by random effect model meta-analysis was performed. The registration number for the protocol of this study in PROSPERO is CRD42022369595.

RESULTS

From the 4421 articles retrieved from the primary search, 118 met the inclusion criteria and were included in the final analysis. After a pooled analysis of 1 729 128 patients, the overall prevalence of hepatic manifestations was 3.49% (95% confidence interval [CI]: 3.31-3.68%; I2: 99.55%). The pooled prevalence of non-alcoholic fatty liver disease in 228 216 patients was 26.1% [95% CI: 22.1-30.2%; I2: 99.018%]. After pooled analysis of 9642 patients, the prevalence of primary sclerosing cholangitis was 1.67% [95% CI: 1.47-1.88%; I2: 99.10%]. The pooled prevalence of biliary stones was 4.1% [95% CI: 3.6-4.7%; I2: 97.43%]. Autoimmune hepatitis (0.51% [95% CI: 0.26-0.75%]; I2: 85.36%) and portal vein thrombosis (0.21% [95% CI: 0.08-0.33%]; I2: 97.95%) are considered as rare manifestations.

CONCLUSION

This study summarizes the prevalence and importance of different hepatic manifestations in IBD patients. These findings are crucial for the management of extraintestinal manifestations, especially hepatic manifestations, in IBD patients.

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.

Intestinal Inflammation and Regeneration-Interdigitating Processes Controlled by Dietary Lipids in Inflammatory Bowel Disease

Inflammatory bowel disease (IBD), including Crohn's disease and ulcerative colitis, is a disease of chronic inflammatory conditions of the intestinal tract due to disturbance of the inflammation and immune system. Symptoms of IBD include abdominal pain, diarrhea, bleeding, reduced weight, and fatigue. In IBD, the immune system attacks the intestinal tract's inner wall, causing chronic inflammation and tissue damage. In particular, interlukin-6 and interlukin-17 act on immune cells, including T cells and macrophages, to amplify the immune responses so that tissue damage and morphological changes occur. Of note, excessive calorie intake and obesity also affect the immune system due to inflammation caused by lipotoxicity and changes in lipids supply. Similarly, individuals with IBD have alterations in liver function after sustained high-fat diet feeding. In addition, excess dietary fat intake, along with alterations in primary and secondary bile acids in the colon, can affect the onset and progression of IBD because inflammatory cytokines contribute to insulin resistance; the factors include the release of inflammatory cytokines, oxidative stress, and changes in intestinal microflora, which may also contribute to disease progression. However, interfering with de novo fatty acid synthase by deleting the enzyme acetyl-CoA-carboxylase 1 in intestinal epithelial cells (IEC) leads to the deficiency of epithelial crypt structures and tissue regeneration, which seems to be due to Lgr5+ intestinal stem cell function. Thus, conflicting reports exist regarding high-fat diet effects on IBD animal models. This review will focus on the pathological basis of the link between dietary lipids intake and IBD and will cover the currently available pharmacological approaches.

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.

What Is the Risk? Epidemiology and Evidence for Surveillance Regimens

Patients with inflammatory bowel disease (IBD) have increased risk of colorectal cancer (CRC). The risk for CRC is positively correlated to the duration of disease, extent of colonic involvement, and severity of inflammation. After 8 to 10 years of IBD diagnosis, the risk for CRC rises substantially and screening colonoscopy is recommended. Surveillance colonoscopy interval ranges from 1 to 5 years depending on patient and disease-specific risk factors. IBD patients with high risk factors such as having concomitant primary sclerosing cholangitis, moderate-to-severe inflammation, first-degree relative with CRC at early age, or history of invisible dysplasia or high-risk visible dysplasia should undergo surveillance colonoscopy in 1 year. Meanwhile, those with minimal colonic involvement or ≥2 consecutive unremarkable examinations while in continuous remission may consider extending the surveillance interval to 5 years. Advance in colonoscopy technique such as chromoendoscopy using dyes and/or image digital processing (virtual chromoendoscopy) may enhance dysplasia detection and is the preferred method for IBD surveillance. In the era of high-definition colonoscope, the practice of obtaining extensive biopsies throughout the colon remains controversial but is generally recommended to improve the detection rate of invisible dysplasia. Endoscopic surveillance in IBD has been shown to result in earlier detection of CRC and improved prognosis.

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).

[Inflammatory bowel diseases: Transformation of representations. A review]

The global burden of inflammatory bowel disease (IBD) is currently significant and continues to grow due to the increasing prevalence of ulcerative colitis (UC) and Crohn's disease (CD), the increasing costs of diagnosis and treatment, and the high level of disability in patients with this disease. Categories, which leads to the search for risk factors and predictors of aggressive course and extraintestinal manifestations. According to the latest data, the prevalence of UC in Russia is 16.6 per 100 000 population, the annual registered increase is 11.3%; the prevalence of CD is 5.6 per 100 000 population, and the increase is 13.7%. In the Russian population of patients with IBD, the average age of disease onset is 35.3 years for UC and 31.2 years for CD. Moreover, in 89.3% of patients with UC, it took at least 2 years to verify the diagnosis, and in CD, within 2 years from the onset of clinical symptoms, the diagnosis was established in only 72.6% of patients. One of the dominant characteristics of IBD is its multisystem nature, which leads to the development of extraintestinal manifestations (ECM), which can be observed in 50-60% of patients, while up to 25% of patients with IBD have several EMC and the most common variants are joint lesions. A higher frequency of extraintestinal manifestations is observed in CD (up to 45% of patients), in female patients, in smokers and with a longer duration of the disease. To predict clinical remission, the level of fecal calprotectin and CRP, the need for glucocorticosteroids are important, to predict endoscopic remission - the level of fecal calprotectin, and to predict histological remission, an endoscopic Schroeder index value of ≤1 is important. The absolute risk of developing colorectal cancer in IBD remains relatively low, ranging from 1.1 to 5.4% after 20 years of disease. The main risk factors for IBD are total intestinal damage, high inflammatory activity, the stricturing phenotype of CD and the presence of primary sclerosing cholangitis.

Candida spp. in Human Intestinal Health and Disease: More than a Gut Feeling

Fungi are an essential part of the normal collection of intestinal microorganisms, even though their collective abundance comprises only 0.1-1% of all fecal microbes. The composition and role of the fungal population is often studied in relation to early-life microbial colonization and development of the (mucosal) immune system. The genus Candida is frequently described as one of the most abundant genera, and altered fungal compositions (including elevated abundance of Candida spp.) have been linked with intestinal diseases such as inflammatory bowel disease and irritable bowel syndrome. These studies are performed using both culture-dependent and genomic (metabarcoding) techniques. In this review, we aimed to summarize existing data on intestinal Candida spp. colonization in relation to intestinal disease and provide a brief overview of the biological and technical challenges in this field, including the recently described role of sub-species strain variation of intestinal Candida albicans. Together, the evidence for a contributing role of Candida spp. in pediatric and adult intestinal disease is quickly expanding, even though technical and biological challenges may limit full understanding of host-microbe interactions.

Current insights on the roles of gut microbiota in inflammatory bowel disease-associated extra-intestinal manifestations: pathophysiology and therapeutic targets

Inflammatory bowel disease (IBD) is a chronic, recurrent inflammatory disease of the gastrointestinal tract. In addition to digestive symptoms, patients with IBD may also develop extra-intestinal manifestations (EIMs), the etiology of which remains undefined. The gut microbiota has been reported to exert a critical role in the pathogenesis of IBD, with a similar pattern of gut dysbiosis observed between patients with IBD and those with EIMs. Therefore, it is hypothesized that the gut microbiota is also involved in the pathogenesis of EIMs. The potential mechanisms are presented in this review, including: 1) impaired gut barrier: dysbiosis induces pore formation in the intestinal epithelium, and activates pattern recognition receptors to promote local inflammation; 2) microbial translocation: intestinal pathogens, antigens, and toxins translocate via the impaired gut barrier into extra-intestinal sites; 3) molecular mimicry: certain microbial antigens share similar epitopes with self-antigens, inducing inflammatory responses targeting extra-intestinal tissues; 4) microbiota-related metabolites: dysbiosis results in the dysregulation of microbiota-related metabolites, which could modulate the differentiation of lymphocytes and cytokine production; 5) immunocytes and cytokines: immunocytes are over-activated and pro-inflammatory cytokines are excessively released. Additionally, we summarize microbiota-related therapies, including probiotics, prebiotics, postbiotics, antibiotics, and fecal microbiota transplantation, to promote better clinical management of IBD-associated EIMs.

TNF-α Mediated the Disruption of Hepatic Tight Junction Expression in Blood-Biliary Barrier of Colitis via Downregulating PI3K/AKT Signaling Pathway

Hepatocyte tight junctions (TJ) constituted blood-biliary barrier is the most important hepatic barrier for separating bile from the bloodstream, disruption or dysfunction of TJ barrier is involved in hepatobiliary manifestations of colitis, but the underlying mechanism is still not clear. This study aims to investigate the effect and underlying mechanism of tumor necrosis factor alpha (TNF-α) on hepatic TJ protein expression in blood-biliary barrier and identify its role in the pathogenesis of acute colitis-related cholestasis. Acute colitis rat model was induced by trinitrobenzene sulfonic acid (TNBS) intra-colonic administration. TJs expression of blood-biliary barrier was tested in colitis rats, the serum TNF-α level was also determined in order to elucidate the correlation of TNF-α and TJs. HepaRG cells were used to investigate the effect of TNF-α on TJs, and the phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) signaling pathway were also evaluated in rats and TNF-α treated HepaRG cells. Acute colitis was induced in rats at 5 d post TNBS, which is accompanied with cholestasis-like alteration. Serum TNF-α level was increased in colitis rats and positively correlated with the alteration of total bile acids and bilirubin, marked decrease in TJs was found in TNF-α treated HepaRG cells and the rats, down-regulated PI3K/AKT signaling pathway were also identified in TNF-α treated HepaRG cells and the rats. The study concluded that serum TNF-α mediated the down-regulation of PI3K/AKT signaling pathway, which contributed to the reduction of TJ protein expression in acute colitis-related intrahepatic cholestasis. These findings suggest that TNF-α plays an important role in the pathogenesis of intrahepatic cholestasis of colitis.

Update on Endoscopic Dysplasia Surveillance in Inflammatory Bowel Disease

As medical management of inflammatory bowel disease makes great advances, most patients with inflammatory bowel disease will have long life expectancies without need for total colectomy. With prolonged disease duration, however, there is increased risk of dysplasia leading to colorectal cancer. Multiple consensus and guideline documents have been published over the last decade with recommendations to optimize early detection and management of dysplastic lesions. Endoscopic technology has improved tremendously, even over the past few years. Previously invisible dysplasia has become visible in most cases with advanced imaging technologies that now allow for much clearer and more detailed mucosal inspection. New tools to facilitate endoscopic resection of visible lesions have also enabled patients to avoid colectomy, with resulting need to continue colon surveillance. There are limited or conflicting data leading to inconsistent recommendations regarding the need for random biopsies, the preferred endoscopic imaging technique, and surveillance intervals after resection of dysplasia. Similarly, there remains significant variability in the application of guidelines into daily practice and availability of and training with advanced imaging technologies. Here, we present a narrative review of which patients are at highest risk for dysplasia, the current guidelines on surveillance colonoscopy, factors affecting optimal mucosal visualization, enhanced imaging techniques, standardized reporting terminologies for surveillance colonoscopy, endoscopic management of dysplasia, indications for colectomy, and briefly on future potential technologies to assist in dysplasia detection.

Low prevalence of primary sclerosing cholangitis in patients with inflammatory bowel disease in India

BACKGROUND/AIMS

Primary sclerosing cholangitis (PSC) represents the most common hepatobiliary extraintestinal manifestation of inflammatory bowel disease (IBD), including ulcerative colitis (UC) and Crohn's disease (CD). Limited data exist on PSC in patients with IBD from India. We aimed to assess the prevalence and disease spectrum of PSC in Indian patients with IBD.

METHODS

Database of IBD patients at 5 tertiary care IBD centers in India were analyzed retrospectively. Data were extracted and the prevalence of PSC-IBD was calculated.

RESULTS

Forty-eight patients out of 12,216 patients with IBD (9,231 UC, 2,939 CD, and 46 IBD unclassified) were identified to have PSC, resulting in a prevalence of 0.39%. The UC to CD ratio was 7:1. Male sex and pancolitis (UC) or colonic CD were more commonly associated with PSC-IBD. The diagnosis of IBD preceded the diagnosis of PSC in most of the patients. Majority of the patients were symptomatic for liver disease at diagnosis. Eight patients (16.66%) developed cirrhosis, 5 patients (10.41%), all UC, developed malignancies (3 colorectal cancer [6.25%] and 2 cholangiocarcinoma [4.16%]), and 3 patients died (2 decompensated liver disease [4.16%] and 1 cholangiocarcinoma [2.08%]) on follow-up. None of the patients mandated surgical therapy for IBD.

CONCLUSIONS

Concomitant PSC in patients with IBD is uncommon in India and is associated with lower rates of development of malignancies.

Ulcerative Colitis in Adults: A Review

Importance

Ulcerative colitis (UC) is a chronic inflammatory condition of the colon, with a prevalence exceeding 400 per 100 000 in North America. Individuals with UC have a lower life expectancy and are at increased risk for colectomy and colorectal cancer.

Observations

UC impairs quality of life secondary to inflammation of the colon causing chronic diarrhea and rectal bleeding. Extraintestinal manifestations, such as primary sclerosing cholangitis, occur in approximately 27% of patients with UC. People with UC require monitoring of symptoms and biomarkers of inflammation (eg, fecal calprotectin), and require colonoscopy at 8 years from diagnosis for surveillance of dysplasia. Risk stratification by disease location (eg, Montreal Classification) and disease activity (eg, Mayo Score) can guide management of UC. First-line therapy for induction and maintenance of remission of mild to moderate UC is 5-aminosalicylic acid. Moderate to severe UC may require oral corticosteroids for induction of remission as a bridge to medications that sustain remission (biologic monoclonal antibodies against tumor necrosis factor [eg, infliximab], α4β7 integrins [vedolizumab], and interleukin [IL] 12 and IL-23 [ustekinumab]) and oral small molecules that inhibit janus kinase (eg, tofacitinib) or modulate sphingosine-1-phosphate (ozanimod). Despite advances in medical therapies, the highest response to these treatments ranges from 30% to 60% in clinical trials. Within 5 years of diagnosis, approximately 20% of patients with UC are hospitalized and approximately 7% undergo colectomy. The risk of colorectal cancer after 20 years of disease duration is 4.5%, and people with UC have a 1.7-fold higher risk for colorectal cancer compared with the general population. Life expectancy in people with UC is approximately 80.5 years for females and 76.7 years for males, which is approximately 5 years shorter than people without UC.

Conclusions and Relevance

UC affects approximately 400 of every 100 000 people in North America. An effective treatment for mild to moderate UC is 5-aminosalicylic acid, whereas moderate to severe UC can be treated with advanced therapies that target specific inflammation pathways, including monoclonal antibodies to tumor necrosis factor, α4β7 integrins, and IL-12 and IL-23 cytokines, as well as oral small molecule therapies targeting janus kinase or sphingosine-1-phosphate.

Use of IBD Drugs in Patients With Hepatobiliary Comorbidities: Tips and Tricks

Advanced therapies (biologic agents and small molecules) for inflammatory bowel diseases (IBD) have radically changed the management of these diseases during the last decade. Data about these drugs in patients with hepatic disorders derive mainly from real-life studies, as these conditions often represent an exclusion criterion from pivotal drug developmental trials. However, IBD patients sometimes have concomitant liver diseases. Nonalcoholic fatty liver disease is the most prevalent hepatic comorbidity, whereas viral hepatitis, primary sclerosing cholangitis, primary biliary cholangitis, autoimmune hepatitis, and hepatic vascular disorders are less frequent. This review aimed at describing the real-life data about the use of advanced therapies for IBD in patients with concomitant hepatobiliary disorders. Hepatitis B virus and hepatitis C virus infections do not represent an absolute contraindication for novel IBD therapeutic agents. Data from the literature suggest a safe hepatobiliary profile of biologic agents and small molecules in the case of nonalcoholic fatty liver disease, autoimmune hepatitis, primary sclerosing cholangitis, primary biliary cholangitis, and portal vein thrombosis. Consequently, although the liver disease does not affect a different therapeutic approach in patients with concomitant IBD and liver disease, a close risk/benefit analysis for each drug should be performed in these patients, especially in cirrhotic patients and in the postliver transplant setting.

Extraintestinal Cancers in Inflammatory Bowel Disease: A Literature Review

BACKGROUND

Inflammatory bowel disease (IBD) is a group of chronic multifactorial inflammatory disorders including two major entities: Crohn's disease (CD) and ulcerative colitis (UC). Preliminary evidence suggests that patients with IBD may be at increased risk of developing intestinal and extraintestinal cancers (EICs). Actually, little is known about the association between IBD and EICs, and there is ever-growing concern regarding the safety of immunomodulators and biological therapy, which may represent a risk factor for carcinogenesis.

AIMS

The aim of this review is to summarize the evidence regarding the association between IBD and EICs, the safety of immunomodulators and biological therapy and the management of immunomodulators and biologic agents in IBD patients with prior or current EICs.

RESULTS

IBD patients have a higher risk of developing different forms of extraintestinal solid organ tumors and hematological malignancies. Immunomodulators and biological therapy may increase the risk of developing some types of EICs and may be consciously used in patients with IBD and current or prior history of malignancy.

CONCLUSIONS

Decisions regarding the use of immunomodulators or biological therapies should be made on an individual basis, considering a multidisciplinary approach involving oncologists.

Recent Advances in the Management of Primary Sclerosing Cholangitis

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease characterized by fibroinflammatory damage to the biliary tree, typically in the setting of inflammatory bowel disease, with an increased risk of liver failure and cholangiocarcinoma. A complex pathophysiology, heterogeneity in clinical features, and the rare nature of the disease have contributed to the lack of effective therapy to date. However, recent innovations in the characterization and prognostication of patients with PSC, in addition to new tools for medical management and emerging pharmacologic agents, give rise to the potential for meaningful progress in the next several years. This review summarizes current concepts in PSC and highlights particular areas in need of further study.

Incidence and adverse clinical events of primary sclerosing cholangitis with ulcerative colitis

PURPOSE

The aim of this study was to conduct a nationwide population-based study to estimate the incidence of primary sclerosing cholangitis in patients with ulcerative colitis (UC-PSC) and investigate healthcare use, medication use, surgery, cancer, and death as adverse clinical events of UC-PSC.

METHODS

We identified incident cases of UC with (UC-PSC) or without PSC (UC-alone) between 2008 and 2018 using health insurance claims data in Korea. Univariate (crude hazard ratio (HR)) and multivariate analyses were performed to compare the risk of adverse clinical events between groups.

RESULTS

A total of 14,406 patients with UC using population-based claims data were detected in the cohort. Overall, 3.38% (487/14,406) of patients developed UC-PSC. During a mean follow-up duration of approximately 5.92 years, the incidence of PSC in patients with UC was 185 per 100,000 person-years. The UC-PSC group showed statistically more frequent healthcare use (hospitalization and emergency department visits: HRs, 5.986 and 9.302, respectively; P < .001), higher immunomodulator and biologic use (azathioprine, infliximab, and adalimumab: HRs, 2.061, 3.457, and 3.170, respectively; P < .001), and higher surgery rate (operation for intestinal obstruction, and colectomy: HRs, 9.728 and 2.940, respectively; P < .001) than did the UC-alone group. The UC-PSC group also showed significantly higher colorectal cancer and biliary tract cancer (HRs, 2.799 and 36.343, respectively; P < .001) and mortality (HR, 4.257) rates than did the UC-alone group.

CONCLUSION

Patients with UC-PSC have higher risks of colorectal cancer, biliary tract cancer, and death than do patients with UC-alone. Although considered a rare disease, managing this complex and costly disease requires recognition of the impact of increased burden on healthcare services.

Colitis ameliorates cholestatic liver disease via suppression of bile acid synthesis

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease characterized by chronic inflammation and progressive fibrosis of the biliary tree. The majority of PSC patients suffer from concomitant inflammatory bowel disease (IBD), which has been suggested to promote disease development and progression. However, the molecular mechanisms by which intestinal inflammation may aggravate cholestatic liver disease remain incompletely understood. Here, we employ an IBD-PSC mouse model to investigate the impact of colitis on bile acid metabolism and cholestatic liver injury. Unexpectedly, intestinal inflammation and barrier impairment improve acute cholestatic liver injury and result in reduced liver fibrosis in a chronic colitis model. This phenotype is independent of colitis-induced alterations of microbial bile acid metabolism but mediated via hepatocellular NF-κB activation by lipopolysaccharide (LPS), which suppresses bile acid metabolism in-vitro and in-vivo. This study identifies a colitis-triggered protective circuit suppressing cholestatic liver disease and encourages multi-organ treatment strategies for PSC.

Ulcerative colitis complicated by primary sclerosing cholangitis and autoimmune hepatitis overlap syndrome: a case report and literature review

Primary sclerosing cholangitis (PSC), autoimmune hepatitis (AIH), and ulcerative colitis (UC) are immune diseases of the digestive system. Some patients develop overlap syndrome, the presentation of two or more of the clinical, biochemical, immunological, and histological features of these conditions simultaneously or sequentially. The incidence of UC in PSC-AIH overlap syndrome is as high as 50%. In contrast, PSC-AIH overlap syndrome is rare in UC patients. However, because it has a low prevalence and has been studied in less detail, PSC is often misdiagnosed as primary biliary cholangitis (PBC) in its early stage. Herein, we reported a case of a 38-year-old male patient who presented to a clinician in 2014 with irregular bowel habits. A colonoscopy suggested UC. In 2016, the patient was found to have abnormal liver function and was diagnosed with PBC by pathology. He was treated with ursodeoxycholic acid (UDCA) but this had no effect on his liver function. Additional liver biopsies in 2018 indicated PBC-AIH overlap syndrome. The patient refused hormone therapy for personal reasons. Following UDCA monotherapy, his liver function remained abnormal. The patient was reexamined after repeated abnormal liver function tests and bowel symptoms. Systematic laboratory testing, imaging diagnosis, colonoscopy, liver biopsy, and various pathological examinations conducted in 2021 were used to diagnose the patient with PSC-AIH-UC overlap syndrome. He was treated with various drugs, including UDCA, methylprednisolone, mycophenolate mofetil, and mesalazine. His liver function improved significantly after treatment and follow-up is ongoing. Our case report highlights the need to raise awareness about rare and difficult-to-diagnose clinical disorders.

Global burden of Liver Disease: 2023 Update

Liver disease accounts for 2 million deaths and is responsible for 4% of all deaths (1 out of every 25 deaths worldwide); approximately 2/3 of all liver related deaths occur in men. Deaths are largely attributable to complications of cirrhosis and hepatocellular carcinoma, with acute hepatitis accounting for a smaller proportion of deaths. The most common causes of cirrhosis worldwide are related to viral hepatitis, alcohol, and nonalcoholic fatty liver disease (NAFLD). Hepatotropic viruses are the etiological factor in most cases of acute hepatitis, but drug-induced liver injury increasingly accounts for a significant proportion of cases. This iteration of the global burden of liver disease is an update of the 2019 version and focuses mainly on areas where significant new information is available like alcohol-associated liver disease, NAFLD, viral hepatitis, and HCC. We also devote a separate section to the burden of liver disease in Africa, an area of the world typically neglected in such documents.

Therapeutic effect of ustekinumab on patients with extra-intestinal manifestations of Crohn's disease

INTRODUCTION

Ustekinumab serves as an important alternative option for patients with various extraintestinal manifestations (EIMs), which leads to poor quality of life and heavy burden of care. Therefore, a comprehensive review summarizing the efficacy and safety of ustekinumab in patients with CDassociated EIMs is needed to provide reference for clinical medication and help with the appliance of precision medicine.

AREAS COVERED

In this review, we collected and summarized the efficacy and paradoxical side effects of ustekinumab in patients with CDassociated EIMs including musculoskeletal, cutaneous, ocular, and hepatobiliary manifestations. This literature review was performed using PubMed to identify and collect relevant studies published in English.

EXPERT OPINION

The effectiveness of ustekinumab on patients with CDassociated EIMs is mainly reflected in musculoskeletal and cutaneous manifestations compared to ocular or hepatobiliary manifestations. Relevant data from large scale cohort studies and prospective randomized trials are needed to further demonstrate the efficacy and safety of ustekinumab in patients with multiple EIMs.

Inflammasome and pyroptosis in autoimmune liver diseases

Autoimmune hepatitis (AIH), primary biliary cholangitis (PBC), primary sclerosing cholangitis (PSC), and IgG4-related sclerosing cholangitis (IgG4-SC) are the four main forms of autoimmune liver diseases (AILDs), which are all defined by an aberrant immune system attack on the liver. Most previous studies have shown that apoptosis and necrosis are the two major modes of hepatocyte death in AILDs. Recent studies have reported that inflammasome-mediated pyroptosis is critical for the inflammatory response and severity of liver injury in AILDs. This review summarizes our present understanding of inflammasome activation and function, as well as the connections among inflammasomes, pyroptosis, and AILDs, thus highlighting the shared features across the four disease models and gaps in our knowledge. In addition, we summarize the correlation among NLRP3 inflammasome activation in the liver-gut axis, liver injury, and intestinal barrier disruption in PBC and PSC. We summarize the differences in microbial and metabolic characteristics between PSC and IgG4-SC, and highlight the uniqueness of IgG4-SC. We explore the different roles of NLRP3 in acute and chronic cholestatic liver injury, as well as the complex and controversial crosstalk between various types of cell death in AILDs. We also discuss the most up-to-date developments in inflammasome- and pyroptosis-targeted medicines for autoimmune liver disorders.