MSC-derived exosomes attenuate hepatic fibrosis in primary sclerosing cholangitis through inhibition of Th17 differentiation

Primary sclerosing cholangitis(PSC)is an autoimmune cholangiopathy characterized by chronic inflammation of the biliary epithelium and periductal fibrosis,with no curative treatment available,and liver transplantation is inevitable for end-stage patients.Human placentalmesenchymal stem cell(hpMSC)-derived exosomes have demonstrated the ability to prevent fibrosis,inhibit collagen production and possess immunomodulatory properties in autoimmune liver disease.Here,we prepared hpMSC-derived exosomes(Exo^(MSC))and further investigated the anti-fibrotic effects and detailed mechanism on PSC based on Mdr2^(−/−)mice and multicellular organoids established from PSC patients.The results showed that Exo^(MSC) ameliorated liver fibrosis in Mdr2^(−/−)mice with significant collagen reduction in the preductal area where Th17 differentiation was inhibited as demonstrated by RNAseq analysis,and the percentage of CD4+IL-17A+T cells was reduced both in Exo^(MSC)-treated Mdr2^(−/−)mice(Mdr2^(−/−)-Exo)in vivo and Exo^(MSC)-treated Th17 differentiation progressed in vitro.Furthermore,Exo^(MSC) improved the hypersecretory phenotype and intercellular interactions in the hepatic Th17 microenvironment by regulating PERK/CHOP signaling as supported by multicellular organoids.Thus,our data demonstrate the antifibrosis effect of Exo^(MSC) in PSC disease by inhibiting Th17 differentiation,and ameliorating the Th17-induced microenvironment,indicating the promising potential therapeutic role of Exo^(MSC) in liver fibrosis of PSC or Th17-related diseases.

Autoimmune hepatitis and primary sclerosing cholangitis after direct-acting antiviral treatment for hepatitis C virus:A case report

BACKGROUND Chronic hepatitis C virus(HCV)infection is a major global health concern that leads to liver fibrosis,cirrhosis,and cancer.Regimens containing direct-acting antivirals(DAAs)have become the mainstay of HCV treatment,achieving a high sustained virological response(SVR)with minimal adverse events.CASE SUMMARY A 74-year-old woman with chronic HCV infection was treated with the DAAs ledipasvir,and sofosbuvir for 12 wk and achieved SVR.Twenty-four weeks after treatment completion,the liver enzyme and serum IgG levels increased,and antinuclear antibody became positive without HCV viremia,suggesting the development of autoimmune hepatitis(AIH).After liver biopsy indicated AIH,a definite AIH diagnosis was made and prednisolone was initiated.The treatment was effective,and the liver enzyme and serum IgG levels normalized.However,multiple strictures of the intrahepatic and extrahepatic bile ducts with dilatation of the peripheral bile ducts appeared on magnetic resonance cholangiopancreatography after 3 years of achieving SVR,which were consistent with primary sclerosing cholangitis.CONCLUSION The potential risk of developing autoimmune liver diseases after DAA treatment should be considered.

Recombinant adeno-associated virus 8-mediated inhibition of microRNA let-7a ameliorates sclerosing cholangitis in a clinically relevant mouse model

BACKGROUND Primary sclerosing cholangitis(PSC)is characterized by chronic inflammation and it predisposes to cholangiocarcinoma due to lack of effective treatment options.Recombinant adeno-associated virus(rAAV)provides a promising platform for gene therapy on such kinds of diseases.A microRNA(miRNA)let-7a has been reported to be associated with the progress of PSC but the potential therapeutic implication of inhibition of let-7a on PSC has not been evaluated.AIM To investigate the therapeutic effects of inhibition of a miRNA let-7a transferred by recombinant adeno-associated virus 8(rAAV8)on a xenobiotic-induced mouse model of sclerosing cholangitis.METHODS A xenobiotic-induced mouse model of sclerosing cholangitis was induced by 0.1% 3,5-Diethoxycarbonyl-1,4-Dihydrocollidine(DDC)feeding for 2 wk or 6 wk.A single dose of rAAV8-mediated anti-let-7a-5p sponges or scramble control was injected in vivo into mice onset of DDC feeding.Upon sacrifice,the liver and the serum were collected from each mouse.The hepatobiliary injuries,hepatic inflammation and fibrosis were evaluated.The targets of let-7a-5p and downstream molecule NF-κB were detected using Western blot.RESULTS rAAV8-mediated anti-let-7a-5p sponges can depress the expression of let-7a-5p in mice after DDC feeding for 2 wk or 6 wk.The reduced expression of let-7a-5p can alleviate hepato-biliary injuries indicated by serum markers,and prevent the proliferation of cholangiocytes and biliary fibrosis.Furthermore,inhibition of let-7a mediated by rAAV8 can increase the expression of potential target molecules such as suppressor of cytokine signaling 1 and Dectin1,which consequently inhibit of NF-κB-mediated hepatic inflammation.CONCLUSION Our study demonstrates that a rAAV8 vector designed for liver-specific inhibition of let-7a-5p can potently ameliorate symptoms in a xenobiotic-induced mouse model of sclerosing cholangitis,which provides a possible clinical translation of PSC of human.

IgG4-related sclerosing cholangitis associated with essential thrombocythemia:A case report

BACKGROUND The complexity of immunoglobulin G4(IgG4)-related diseases and their potential connection to hematologic malignancies remains unclear.This article provided a review of the diagnosis and treatment of a patient with IgG4-related sclerosing cholangitis(SC)and essential thrombocythemia(ET),along with an analysis of relevant literature to enhance comprehension of this disease.CASE SUMMARY A 56-year-old male was admitted to two hospitals with deteriorating jaundice and pruritus prior to hospitalization.Beyond our expectations,the patient was first diagnosed with IgG4-SC and ET with the Janus kinase 2 V617F mutation.Interestingly,the administration of acetate prednisone significantly resulted in improvements in both IgG4-SC and ET.Clinicians need to pay attention to immune disorders and inflammation as they contribute to the development of various disease phenotypes.CONCLUSION When IgG4-SC is suspected without histopathological evidence,diagnostic therapy and long-term regular follow-up can lead to positive treatment outcomes.Clinicians should be mindful of the potential presence of concurrent hematologic diseases in patients with immune disorders.

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

BACKGROUND Ulcerative colitis(UC)with concomitant primary sclerosing cholangitis(PSC)represents a distinct disease entity(PSC-UC).Mayo endoscopic subscore(MES)is a standard tool for assessing disease activity in UC but its relevance in PSC-UC remains unclear.AIM To assess the accuracy of MES in UC and PSC-UC patients,we performed histological scoring using Nancy histological index(NHI).METHODS MES was assessed in 30 PSC-UC and 29 UC adult patients during endoscopy.NHI and inflammation were evaluated in biopsies from the cecum,rectum,and terminal ileum.In addition,perinuclear anti-neutrophil cytoplasmic antibodies,fecal calprotectin,body mass index,and other relevant clinical characteristics were collected.RESULTS The median MES and NHI were similar for UC patients(MES grade 2 and NHI grade 2 in the rectum)but were different for PSC-UC patients(MES grade 0 and NHI grade 2 in the cecum).There was a correlation between MES and NHI for UC patients(Spearman's r=0.40,P=0.029)but not for PSC-UC patients.Histopathological examination revealed persistent microscopic inflammation in 88%of PSC-UC patients with MES grade 0(46%of all PSC-UC patients).Moreover,MES overestimated the severity of active inflammation in an additional 11%of PSCUC patients.CONCLUSION MES insufficiently identifies microscopic inflammation in PSC-UC.This indicates that histological evaluation should become a routine procedure of the diagnostic and grading system in both PSC-UC and PSC.

Journey to diagnosis:An unfinished exploration of IgG4-related sclerosing cholangitis

IgG4-related sclerosing cholangitis(IgG4-SC)is an inflammatory disease that leads to bile duct stricture,characterized by the infiltration of IgG4-positive plasma cells into the bile duct wall,thickening of the bile duct wall,and narrowing of the lumen.The differential diagnosis of IgG4-SC mainly includes primary sclerosing cholangitis,cholangiocarcinoma,and pancreatic cancer.IgG4-SC is often associated with autoimmune pancreatitis and can be accurately diagnosed based on clinical diagnostic criteria.However,isolated IgG4-SC is difficult to distinguish from biliary tumors.Given the significant differences in biological behavior,treatment,and prognosis between these diseases,accurately identifying isolated IgG4-SC has very important clinical significance.

Inflammatory bowel disease of primary sclerosing cholangitis:A distinct entity?

This is a review of the characteristic findings of inflammatory bowel disease(IBD)associated with primary sclerosing cholangitis(PSC)and their usefulness in the diagnosis of sclerosing cholangitis.PSC is a chronic inflammatory disease characterized by idiopathic fibrous obstruction and is frequently associated with IBD.IBDassociated with PSC(PSC-IBD)shows an increased incidence of pancolitis,mild symptoms,and colorectal malignancy.Although an increased incidence of pancolitis is a characteristic finding,some cases are endoscopically diagnosed as right-sided ulcerative colitis.Pathological studies have revealed that inflammation occurs more frequently in the right colon than the left colon.The frequency of rectal sparing and backwash ileitis should be investigated in a future study based on the same definition.The cholangiographic findings of immunoglobulin G4-related sclerosing cholangitis(IgG4-SC)are similar to those of PSC.The rare association between IBD and IgG4-SC and the unique characteristics of PSC-IBD are useful findings for distinguishing PSC from IgG4-SC.

Liver transplant in primary sclerosing cholangitis:Current trends and future directions

Primary sclerosing cholangitis(PSC)is a chronic and progressive immunemediated cholangiopathy causing biliary tree inflammation and scarring,leading to liver cirrhosis and end-stage liver disease.Diagnosis of PSC is challenging due to its nonspecific symptoms and overlap with other liver diseases.Despite the rising incidence of PSC,there is no proven medical therapy that can alter the natural history of the disease.While liver transplantation(LT)is the most effective approach for managing advanced liver disease caused by PSC,post-transplantation recurrence of PSC remains a challenge.Therefore,ongoing research aims to develop better therapies for PSC,and continued efforts are necessary to improve outcomes for patients with PSC.This article provides an overview of PSC’s pathogenesis,clinical presentation,and management options,including LT trends and future aspects.It also highlights the need for improved therapeutic options and ethical considerations in providing equitable access to LT for patients with PSC.Additionally,the impact of liver transplant on the quality of life and psychological outcomes of patients with PSC is discussed.Ongoing research into PSC’s pathogenesis and post-transplant recurrence is crucial for improved understanding of the disease and more effective treatment options.

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.

Intrahepatic cholangiocarcinoma in patients with primary sclerosing cholangitis and ulcerative colitis: Two case reports

BACKGROUND Primary sclerosing cholangitis(PSC)is an extraintestinal manifestation of ulcerative colitis(UC).PSC is a well-known risk factor for intrahepatic cholangiocarcinoma(ICC),and ICC is known to have a poor prognosis.CASE SUMMARY We present two cases of ICC in patients with PSC associated with UC.In the first case,a tumor was found by magnetic resonance imaging(MRI)in the liver of a patient with PSC and UC who presented to our hospital with right-sided rib pain.The second patient was asymptomatic,but we unexpectedly detected two liver tumors in an MRI performed to evaluate bile duct stenosis associated with PSC.ICC was strongly suspected by computed tomography and MRI in both cases,and surgery was performed,but unfortunately,the first patient died of ICC recurrence 16 mo postoperatively,and the second patient died of liver failure 14 mo postoperatively.CONCLUSION Careful follow-up of patients with UC and PSC with imaging and blood tests is necessary for early detection of ICC.

Cholangiocarcinoma, Primary Sclerosing Cholangitis, or IgG4-Sclerosing Cholangitis: Similar Presentations with Different Managements

In our case, we present a case of an 80-year-old male who was referred to the gastroenterologist for evaluation of a suspicious mass. CT imaging at the time had shown intrahepatic and extrahepatic biliary dilations, and the patient was thought to have a pancreatic or a common bile duct mass. A mass biopsy showed no malignancy, and further evaluation was warranted. The patient was found to have elevated IgG4 levels and was diagnosed with IgG4-sclerosing cholangitis (IgG4-SC). IgG4 has been found to create a wide array of pathologies, including autoimmune pancreatitis, dacryoadenitis, and sialadenitis. These pathologies have been grouped under an IgG4-Related Disease (IgG4-RD) category. In some cases, this IgG4-RD can present as a subclass of primary sclerosing cholangitis due to immune depositions and swelling of the CBD. Due to the strictures caused by the sclerosing cholangitis, intrahepatic and extrahepatic dilations might be found on endoscopic ultrasound (EUS). It is imperative to differentiate this from a malignant mass as the early recognition and treatment of IgG4-SC can lead to complete resolution. In this case report, we present a case of a patient who was found to have IgG4-SC and responded well to steroid treatment.

First case of IgG4-related sclerosing cholangitis associated with autoimmune hemolytic anemia

To our knowledge,patients with immunoglobulin G4-related sclerosing cholangitis(IgG4-SC)associated with autoimmune hemolytic anemia(AIHA)have not been reported previously.Many patients with IgG4-SC have autoimmune pancreatitis(AIP)and respond to steroid treatment.However,isolated cases of IgG4-SC are difficult to diagnose.We describe our experience with a patient who had IgG4-SC without AIP in whom the presence of AIHA led to diagnosis.The patient was a73-year-old man who was being treated for dementia.Liver dysfunction was diagnosed on blood tests at another hospital.Imaging studies suggested the presence of carcinoma of the hepatic hilus and primary sclerosing cholangitis,but a rapidly progressing anemia developed simultaneously.After the diagnosis of AIHA,steroid treatment was begun,and the biliary stricture improved.IgG4-SC without AIP was thus diagnosed.

Review of primary sclerosing cholangitis with increased IgG4 levels

Primary sclerosing cholangitis(PSC) is a chronic progressive liver disease. Subtypes of PSC have been described, most recently PSC with elevated serum and/or tissue IgG4 subclass. We aim to summarise the clinical phenotype,disease associations, differential diagnosis, response to therapy and pathogenic mechanisms underlying PSC-high IgG4 subtype. We reviewed Pub Med,MEDLINE and Embase with the search terms "primary sclerosing cholangitis","IgG4", and "IgG4-related sclerosing cholangitis(IgG4-SC)". Elevated serum IgG4 are found in up-to one-quarter, and abundant IgG4-plasma cell infiltrates in the liver and bile ducts are found in up-to one-fifth of PSC patients. This group have a distinct clinical phenotype, with some studies reporting a more aggressive course of liver and associated inflammatory bowel disease, compared to PSCnormal IgG4 and the disease mimic IgG4-SC. Distinguishing PSC-high IgG4 from IgG4-SC remains challenging, requiring careful assessment of clinical features,organ involvement and tissue morphology. Calculation of serum IgG4:IgG1 ratios and use of a novel IgG4:IgG RNA ratio have been reported to have excellent specificity to distinguish IgG4-SC and PSC-high IgG4 but require validation in larger cohorts. A role for corticosteroid therapy in PSC-high IgG4 remains unanswered, with concerns of increased toxicity and lack of outcome data. The immunological drivers underlying prominent IgG4 antibodies in PSC are incompletely defined. An association with PSC-high IgG4 and HLA class-II haplotypes(B*07, DRB1*15), T-helper2 and T-regulatory cytokines(IL4, IL10,IL13) and chemokines(CCL1, CCR8) have been described. PSC-high IgG4 have a distinct clinical phenotype and need careful discrimination from IgG4-SC,although response to immunosuppressive treatments and long-term outcome remains unresolved. The presence of IgG4 likely represents chronic activation to persistent antigenic exposure in genetically predisposed individuals.

Small duct primary sclerosing cholangitis: A discrete variant or a bridge to large duct disease, a practical review

The natural history,associations with inflammatory bowel disease(IBD),and long-term outcomes of large duct primary sclerosing cholangitis(ldPSC)have been well documented.Small duct primary sclerosing cholangitis(sdPSC)is a much less common and relatively more benign variant.The natural history of sdPSC has been difficult to characterize given the limited number of studies in the literature especially with regards to the subset of patients who progress to large duct involvement.It has been unclear whether sdPSC represented a subset of ldPSC,an earlier staging of ldPSC,or a completely separate and distinct entity of its own.Strong associations between sdPSC and IBD have been established with suspicion that concurrent sdPSC-IBD may be a key prognostic factor in determining which patients are at risk of progression to ldPSC.Little is known regarding the discrete circumstances that predisposes some patients with sdPSC to progress to ldPSC.It has been suspected that progression to large biliary duct involvement subjects this subset of patients to potentially developing lifethreatening complications.Here the authors conducted a thorough review of the published sdPSC literature using Pubmed searches and cross-referencing to compile all accessible studies regarding cohorts of sdPSC patients in order better characterize the subset of sdPSC patients who progress to ldPSC and the associated outcomes.

Concurrent systemic AA amyloidosis can discriminate primary sclerosing cholangitis from IgG4-associated cholangitis

Chronic hepatobiliary inflammatory diseases are not widely acknowledged as underlying disorders of systemic AA amyloidosis,except epidemic schistosomiasis.Among them,primary sclerosing cholangitis (PSC) might initiate amyloid A protein deposition in diverse tissues,giving rise to systemic amyloidosis,due to a progressive and unresolved inflammatory process,and its possible association with inflammatory bowel diseases.Nevertheless,only one such case has been reported in the literature to date.We report a 69-year-old Japanese woman with cirrhosis who was diagnosed with PSC complicated with systemic AA amyloidosis,without any evidence of other inflammatory disorders.As a result of cholestasis in conjunction with biliary strictures and increased serum IgG4,the presence of IgG4 + plasma cells was examined systemically,resulting in unexpected documentation of Congo-red-positive amyloid deposits,but not IgG4 + plasma cells,in the liver,stomach and salivary glands.Elevated serum IgG4 is the hallmark of IgG4-related disease,including IgG4-associated cholangitis,but it has also been demonstrated in certain patients with PSC.Amyloid A deposits in multiple organs associated with an indolent clinical course that progresses over many years might have a diagnostic value in discriminating PSC from IgG4-associated cholangitis.

Resected case of eosinophilic cholangiopathy presenting with secondary sclerosing cholangitis

Eosinophilic cholangiopathy is a rare condition characterized by eosinophilic infiltration of the biliary tract and causes sclerosing cholangitis. We report a patient with secondary sclerosing cholangitis with eosinophilic cholecystitis. A 46-year-old Japanese man was admitted to our hospital with jaundice. Computed tomography revealed dilatation of both the intrahepatic and extrahepatic bile ducts, diffuse thickening of the wall of the extrahepatic bile duct, and thickening of the gallbladder wall. Under the diagnosis of lower bile duct carcinoma, he underwent pyloruspreserving pancreatoduodenectomy and liver biopsy. On histopathological examination, conspicuous fibrosis was seen in the lower bile duct wall. In the gallbladder wall, marked eosinophilic infiltration was seen. Liver biopsy revealed mild portal fibrosis. He was diagnosed as definite eosinophilic cholecystitis with sclerosing cholangitis with unknown etiology. The possible etiology of sderosing cholangitis was consequent fibrosis from previous eosinophilic infiltration in the bile duct. The clinicopathological findings of our case and a literature review indicated that eosinophilic cholangiopathy could cause a condition mimicking primary sclerosing cholangitis （PSC）. Bile duct wall thickening in patients with eosinophilic cholangitis might be due to fibrosis of the bile duct wall. Eosinophilic cholangiopathy might be confused as PSC with eosinophilia.

Distinct gut microbiota profiles in patients with primary sclerosing cholangitis and ulcerative colitis

To characterize the gut bacterial microbiota of patients with primary sclerosing cholangitis (PSC) and ulcerative colitis (UC). METHODSStool samples were collected and relevant clinical data obtained from 106 study participants, 43 PSC patients with (n = 32) or without (n = 11) concomitant inflammatory bowel disease, 32 UC patients, and 31 healthy controls. The V3 and V4 regions of the 16S ribosomal RNA gene were sequenced on Illumina MiSeq platform to cover low taxonomic levels. Data were further processed in QIIME employing MaAsLin and LEfSe tools for analysis of the output data. RESULTSMicrobial profiles in both PSC and UC were characterized by low bacterial diversity and significant change in global microbial composition. Rothia, Enterococcus, Streptococcus, Veillonella, and three other genera were markedly overrepresented in PSC regardless of concomitant inflammatory bowel disease (IBD). Rothia, Veillonella and Streptococcus were tracked to the species level to identify Rothia mucilaginosa, Streptococcus infantus, S. alactolyticus, and S. equi along with Veillonella parvula and V. dispar. PSC was further characterized by decreased abundance of Adlercreutzia equolifaciens and Prevotella copri. Decrease in genus Phascolarctobacterium was linked to presence of colonic inflammation regardless of IBD phenotype. Akkermansia muciniphila, Butyricicoccus pullicaecorum and Clostridium colinum were decreased in UC along with genus Roseburia. Low levels of serum albumin were significantly correlated with enrichment of order Actinomycetales. CONCLUSIONPSC is associated with specific gut microbes independently of concomitant IBD and several bacterial taxa clearly distinguish IBD phenotypes (PSC-IBD and UC).

Primary sclerosing cholangitis as an independent risk factor for colorectal cancer in the context of inflammatory bowel disease: A review of the literature

To examine and evaluate recent evidence regarding the epidemiology, pathogenesis and management of colorectal cancer(CRC) development in inflammatory bowel disease(IBD)-primary sclerosing cholangitis(PSC) patients. Using the PubMed database, a literature search was conducted for relevant articles in English from the past 10 years. Relevant studies investigating PSC as a risk factor for CRC in IBD in the context of incidence and prevalence, pathogenesis, prevention and prognosis were included in this review. Recent evidence increasingly points to PSC as a significant risk factor in the development of CRC in patients with concomitant IBD. PSC may be an important risk factor for CRC in different populations worldwide. The mechanism for this increase in risk is still unclear. The efficacy of UDCA as a chemopreventive agent remains controversial. Liver transplantation does not halt the development of CRC, although there is not enough evidence to suggest that it is associated with increased incidence of CRC. While routine colonoscopic surveillance should be performed in patients with concurrent PSC and IBD, more high-level evidence is required to support the benefits of the procedure. While many new developments have taken place in the last decade, the pathogenesis and optimal management of CRC development in IBD-PSC patients remain unclear.

Primary sclerosing cholangitis, autoimmune hepatitis and overlap syndromes in inflammatory bowel disease

Primary sclerosing cholangitis （PSC） is a chronic progressive disorder of unknown aetiology characterised by chronic inflammation and stricture formation of the biliary tree. Symptoms include itch and lethargy and in advanced cases cholangitis and end-stage liver disease, however increasing numbers of asymptomatic individuals are being identified. The disease is rare in the general population but is strongly associated with inflammatory bowel disease （IBD） affecting up to 5% of patients with Ulcerative Colitis, with a slightly lower prevalence （up to 3.6%） in Crohns disease. The strength of this association means that the vast majority （ 〉 90%） of patients with PSC also have IBD, although many may have only mild gastro-intestinal symptoms. Usually IBD presents before PSC, although vice-versa can occur and the onset of both conditions can be separated in some cases by many years. Mean age of diagnosis of PSC is in the fitch decade of life with a strong male predominance. Risk is increased in those with a family history of PSC, suggesting a genetic predisposition and the disease is almost exclusive to non-smokers. The ulcerative colitis associated with PSC is characteristically mild, runs a quiescent course, is associated with rectal sparing, more severe right sided disease, backwash ilieitis and has a high risk of pouchitis post-colectomy. Most worrisome is the high risk of colorectal malignancy which necessitates routine colonoscopic surveillance. Cholangiocarcinoma is also a frequent complication of PSC with a 10%-15% lifetime risk of developing this condition. Treatment with high dose ursodeoxycholic acid offers some chemoprotective effects against colorectal malignancy and may decrease symptoms, biochemical and histological progression of liver disease. Small duct PSC patients characteristically have normal cholangiography, and liver biopsy is required for diagnosis, it appears to have a more favourable prognosis. Autoimmune Hepatitis （AIH） is also more prevalent in patients with IBD, with up to 16% of patients with Autoimmune Hepatitis also having ulcerative colitis. A small subgroup of patients have a AIH-PSC overlap syndrome and the management of these patients depends on liver histology, serum IgM levels, autoantibodies, degree of biochemical cholestasis and cholangiography as some of these patients may respond to immunosupression.

Sclerosing cholangitis associated with autoimmune pancreatitis differs from primary sclerosing cholangitis

AIM:To clarify the characteristic features of biliary le-sions in patients with autoimmune pancreatitis(AIP) and compare them with those of primary sclerosing cholangitis(PSC) .METHODS:The clinicopathological characteristics of 34 patients with sclerosing cholangitis(SC) associated with AIP were compared with those of 4 patients with PSC.RESULTS:SC with AIP occurred predominantly in el-derly men.Obstructive jaundice was the most frequent initial symptom in SC with AIP.Only SC patients with AIP had elevated serum IgG4 levels,and sclerosing diseases were more frequent in these patients.SC pa-tients with AIP responded well to steroid therapy.Seg-mental stenosis of the lower bile duct was observed only in SC patients with AIP,but a beaded and pruned-tree appearance was detected only in PSC patients.Dense infi ltration of IgG4-positive plasma cells was de-tected in the bile duct wall and the periportal area,as well as in the pancreas,of SC patients with AIP.CONCLUSION:SC with AIP is distinctly different from PSC.The two diseases can be discriminated based on cholangiopancreatographic findings and serum IgG4 levels.