Primary Sclerosing Cholangitis Associated with Elevated ImmunoglobulinG4: Clinical Characteristics and Response to Therapy

Secondary Sclerosing Cholangitis due to Drugs With a Special Emphasis on Checkpoint Inhibitors

BACKGROUND

Secondary sclerosing cholangitis (SSC), is one of the phenotypes of DILI first described in the 1980s. Check point inhibitors (CPIs) are currently the most frequent cause of SCC.

AIMS

To describe the epidemiology, clinical and biochemical features at presentation, differential diagnoses, pathophysiology, imaging, histological characteristics and management associated with SSC.

MATERIALS AND METHODS

A language and date-unrestricted Medline literature search was conducted to identify case reports and clinical series on SSC with special emphasis on CPIs (2007-2023).

RESULTS

We identified 19 different drugs that have been shown to induce SSC. A total of 64 cases with SSC due to CPIs are presented. This was mostly seen in patients treated with anti-Programmed cell death (PD)-1/PD-L1 inhibitors. The most frequent presenting signs and symptoms were abdominal pain and jaundice. Large-duct cholangitis induced by CPIs is a very rare condition while small-duct cholangitis is more common. Nivolumab and pembrolizumab were the most commonly implicated agents. Biopsies have revealed predominant CD8+ T cell infiltration in biliary strictures. Corticosteroids is linked to a low frequency of success and is the only agent recommended to begin the treatment.

CONCLUSIONS

CPIs-induced SSC seems to affect the entire biliary system. Clinicians should consider and suspect SSC when a probable CPIs-induced hepatitis does not respond to corticosteroids. Additionally, further randomized, controlled trials should prospectively investigate alternative therapies for treatment.

Only repeatedly elevated IgG4 levels in primary sclerosing cholangitis may distinguish a particular patient phenotype

BACKGROUND

Primary sclerosing cholangitis (PSC) is a chronic liver disease leading to inflammation with scaring and strictures of bile ducts, which can lead to liver cirrhosis. A subtype of PSC characterized by high serum IgG4 (sIgG4) levels has been reported to be associated with poor outcomes, but the exact role and the longitudinal development of sIgG4 levels in PSC progression remains to be clarified. The aim of this study was to investigate if subsequent analysis of sIgG4 levels allows the identification of the PSC phenotype with high sIgG4.

METHODS

sIgG4 values were repeatedly analysed in a well-characterized European PSC cohort of 110 individuals. Biochemical parameters, clinical endpoints, death and liver transplantation were compared between PSC subgroups.

RESULTS

12.7% (n = 14) of PSC patients showed increased sIgG4 levels (PSC-IgG4). The values normalized in 57.1% (n = 8; PSC-IgG4norm) during follow-up measurements, whereas the values remained permanently elevated in 42.9% (n = 6; PSC-IgG4const). Serum values of AP and γGT were significantly higher in PSC-IgG4const compared to PSC-IgG4norm at final blood sampling. Furthermore, mean age at PSC diagnosis was markedly lower in PSC-IgG4const compared to PSC-IgG4norm.

CONCLUSIONS

This is the first study analyzing longitudinal development of sIgG4 in PSC. Our data indicate that only sequential determination of sIgG4 levels allow to accurately distinguish between the PSC phenotype with high sIgG4 and PSC with low sIgG4.

Primary sclerosing cholangitis with IgG4-positive plasma cells in bile duct biopsies - Frequency and characterization

OBJECTIVES

Patients diagnosed with primary sclerosing cholangitis (PSC) but with characteristics of immunoglobulin G4 (IgG4)-associated cholangitis (IAC) have been described. IAC often presents with biliary IgG4-positive plasma cell (IgG4+ PC) infiltration and responds to corticosteroids. In PSC, the frequencies or implications of biliary IgG4+ PC are unknown. We aimed to characterize the phenomenon of biliary IgG4+ PC in patients with an established PSC diagnosis.

METHODS

Bile duct biopsies from 191 surveillance or therapeutic endoscopic retrograde cholangiography of 58 PSC patients were retrospectively analyzed for IgG4+ PC infiltration. Patients with ≥10 IgG4+ PC per high-power field (HPF) were identified and characterized by clinical parameters, including serum IgG4 and cholangiographic presentations.

RESULTS

Altogether 39.7% of the PSC patients showed ≥10 IgG4+ PC/HPF in bile duct biopsies. Patients with biliary IgG4+ PC infiltration were significantly younger at diagnosis of PSC (P = 0.023). There was no association between biliary IgG4+ PC infiltration and transplant-free survival (P = 0.618). Patients with IgG4+ PC infiltration in bile duct biopsies showed significantly higher baseline (P = 0.002) and maximum (P = 0.001) serum IgG4 compared to those without. Biliary IgG4+ PC infiltration was associated with high-grade bile duct strictures (P = 0.05). IgG4-positive plasma cell infiltrations were found multifocally in 72.7% of this subgroup of PSC patients.

CONCLUSIONS

IgG4+ PC ≥10/HPF can be found abundantly in bile duct biopsies in PSC. Histological findings correlated with serum IgG4, age, and high-grade bile duct strictures. IgG4+ PC was located multifocally, hinting at a systemic biliary phenotype.

Fibrotic phenotype of IgG4-related disease

A prompt response to glucocorticoids is a clinical hallmark of IgG4-related disease. However, manifestations characterised by prominent tissue fibrosis on histological examination can be less responsive to glucocorticoid therapy than other types of IgG4-related disease. These manifestations include retroperitoneal fibrosis, fibrosing mediastinitis, Riedel thyroiditis, orbital pseudotumor, and hypertrophic pachymeningitis, among others. To explain this discrepancy, a preliminary distinction into proliferative and fibrotic phenotypes of IgG4-related disease has been proposed on the basis of clinical presentation, pathological features, and response to immunosuppressive therapy. Implications of this classification for patient management remain an important area of investigation. In this Series paper, we aim to dissect the pathophysiology of tissue fibrosis in IgG4-related disease and discuss how clinicians should approach the management of fibrotic manifestations of IgG4-related disease based on the most recent diagnostic and therapeutic developments.

Diagnostic Tests in Primary Sclerosing Cholangitis: Serology, Elastography, Imaging, and Histology

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease characterized by progressive inflammation and fibrosis of the biliary tree leading to biliary strictures, cholangitis, and cirrhosis. Early in presentation, patients may have normal liver tests, though over time develop a cholestatic pattern of liver injury. Diagnosis is made radiographically with magnetic resonance or endoscopic cholangiography. While several autoantibodies are associated with PSC, none have proven to have adequate diagnostic utility. Liver biopsy is rarely recommended unless to evaluate for small-duct PSC or overlap syndrome. Elastography, in various forms, is an effective, non-invasive modality to evaluate liver fibrosis in PSC.

Complete Biochemical Remission With Oral Vancomycin in a Patient With Primary Sclerosing Cholangitis and High Serum Immunoglobulin G4 Levels

Primary sclerosing cholangitis (PSC) is a progressive cholestatic liver disease characterized by intrahepatic and extrahepatic bile duct strictures leading to cirrhosis. A subtype with elevated serum immunoglobulin (Ig) G4 levels has been recently identified. Elevated IgG4 titers can be present in 9%-15% of patients with PSC. Currently, liver transplantation is the only effective treatment of PSC, although multiple medical therapies are under evaluation. We report a case of a young adult with PSC and elevated IgG4 levels who had marked serum aminotransferase elevation; the patient had an incomplete response to steroids but achieved complete biochemical remission after initiation of oral vancomycin.

The Role of Immunoglobulin G4 in Outcomes of Primary Sclerosing Cholangitis

INTRODUCTION

Primary sclerosing cholangitis (PSC) is a chronic, cholestatic liver disease that is characterized by an inflammatory and fibrotic process affecting bile ducts which eventually develops into liver cirrhosis and liver failure. The aim of this study was to investigate serum IgG subclass distribution in patients with PSC and its possible association with PSC outcomes.

PATIENTS AND METHODS

We performed a retrospective analysis of 181 patients who had been diagnosed with PSC between January 1970 and December 2015 and followed at our outpatient clinic. Their demographic, immunological, and clinical characteristics were recorded and analyzed.

RESULTS

This study included 181 patients with PSC (120 males, 61 females). There was no association between IgGs and the development of autoimmune hepatitis, cirrhosis, cholangiocarcinoma, liver transplantation, inflammatory bowel disease, and colectomy. Patients with elevated IgG4 had statistically significant higher rates of cholangitis (p = 0.02) and endoscopic retrograde cholangiopancreatography (ERCP) (p = 0.009). High IgG4 values were observed in nine patients who underwent ERCP. In these nine patients, on average, IgG4 was evaluated 5 years after ERCP (min 3 days, max 11 years). Subanalysis considering only IgG4 values evaluated before ERCP showed no significant difference but remains significant if we consider IgG4 values after ERCP.

CONCLUSION

Elevated IgG4 in our study showed a possible association with higher rates of cholangitis and ERCP among patients with primary sclerosing cholangitis. It seems that IgGs may be a useful tool for the prediction of outcomes in patients with PSC. A prospective study is necessary, especially to study the trends of IgGs values during disease as well as the role of possible seroconversion.

EASL Clinical Practice Guidelines on sclerosing cholangitis

Management of primary or secondary sclerosing cholangitis is challenging. These Clinical Practice Guidelines have been developed to provide practical guidance on debated topics including diagnostic methods, prognostic assessment, early detection of complications, optimal care pathways and therapeutic (pharmacological, endoscopic or surgical) options both in adults and children.

Serological biomarkers for management of primary sclerosing cholangitis

Clinical manifestations and progression of primary sclerosing cholangitis (PSC) are heterogeneous, and its pathogenesis is poorly understood. The importance of gut-liver interactions in the pathogenesis has been clinically confirmed and highlighted in different theories. Recent advances regarding biomarkers of biliary-gut crosstalk may help to identify clinically relevant PSC subgroups assisting everyday clinical work-up (e.g., diagnosis, disease stratification, or surveillance) and the exploration of potential therapeutic targets. Alkaline phosphatase produced by the biliary epithelium is consistently associated with prognosis. However, its level shows natural fluctuation limiting its use in individual patients. Inflammatory, cell activation, and tissue remodeling markers have been reported to predict clinical outcome. Elevated immunoglobulin (Ig) G4 level is associated with a shorter transplantation-free survival. IgG type atypical perinuclear anti-neutrophil cytoplasmic antibodies (P-ANCAs) are non-specific markers of various autoimmune liver diseases and may reflect an abnormal B-cell response to gut microbial antigens. IgG type atypical P-ANCA identifies PSC patients with particular clinical and genetic (for human leukocyte antigens) characteristics. The presence of IgA type anti-F-actin antibody (AAA) may predict a progressive disease course, and it is associated with enhanced mucosal immune response to various microbial antigens and enterocyte damage. IgA type anti-glycoprotein 2 (GP2) antibodies identify patients with a severe disease phenotype and poor survival due to enhanced fibrogenesis or development of cholangiocarcinoma. Elevated soluble vascular adhesion protein-1 (sVAP-1) level is associated with adverse disease outcomes in PSC. High sVAP-1 levels correlate with mucosal addressin cell adhesion molecule-1 (MAdCAM-1) expression in the liver that contributes to gut activated T-cell homing to the hepatobiliary tract. In the present paper, we review the evidence on these possible serological markers that could potentially help address the unmet clinical needs in PSC.

Clinical Utility of Personalized Serum IgG Subclass Ratios for the Differentiation of IgG4-Related Sclerosing Cholangitis (IgG4-SC) from Primary Sclerosing Cholangitis (PSC) and Cholangiocarcinoma (CCA)

BACKGROUND

The differential diagnosis of immunoglobulin G4-sclerosing cholangitis (IgG4-SC) from primary sclerosing cholangitis (PSC) or cholangiocarcinoma (CCA) is important. In this study, we aimed to find the best combinations of serum IgG subclasses and IgG4 levels for differentiating IgG4-SC from PSC or CCA.

METHODS

In total, 31 patients with IgG4-SC, 27 patients with PSC, and 40 patients with CCA were enrolled from 2003 to 2017 at a single tertiary referral center. We retrospectively assessed the IgG4, IgG4/IgG1, IgG4/(IgG1+IgG3), and (IgG4+IgG2)/(IgG1+IgG3) in each of the patients. ROC curves were established to obtain the optimal cutoff value for each parameter. McNemar's test was used to compare the sensitivities, specificities, and accuracies of diagnostic algorithms.

RESULTS

In differentiating IgG4-SC from PSC, the accuracies of IgG4/IgG1 ≥ 0.087 and of IgG4/(IgG1+IgG3) ≥ 0.081 were significantly higher than that of IgG4 ≥ 135 mg/dL alone (78% vs. 66%, p = 0.025). Serum IgG4 ≥ 52 mg/dL showed the best accuracy for differentiation of IgG4-SC from CCA, with a sensitivity and specificity of 80% and 82%, respectively, but this was statistically not significant (p = 0.405).

CONCLUSIONS

The serum IgG4/IgG1 or IgG4/(IgG1+IgG3) level may help to differentiate IgG4-SC from PSC. IgG4 alone is the most accurate serologic marker for the differentiation of IgG4-SC from CCA.

Cutting edge issues in juvenile sclerosing cholangitis

Sclerosing cholangitis (SC) is a rare chronic disorder characterised by inflammation and progressive obliterative fibrosis of the intrahepatic and/or extrahepatic bile ducts. Diagnosis is based on cholangiogram showing bile duct dilatation, narrowing and obliteration of the biliary tree, and histologically, on the presence of inflammatory bile duct damage leading to periductal fibrosis. In children the most common SC is associated with strong autoimmune features, overlapping with those of autoimmune hepatitis (AIH); this form is known as autoimmune sclerosing cholangitis, ASC. Conversely, primary SC (PSC), a condition in which the term "primary" indicates that aetiology and pathogenesis are unknown, is rare in paediatrics. Secondary SC (SSC) defines a cholangiopathy associated with an identifiable aetiology such as immunodeficiencies, infections or haematological disorders. ASC and PSC are strongly associated with inflammatory bowel disease (IBD). ASC responds biochemically well to immunosuppressive drugs and ursodeoxycholic acid (UDCA). Primary forms are exclusively managed with oral UDCA, while in the secondary forms the medical treatment depends on the underlying aetiology. Despite treatment, SC often progresses to biliary cirrhosis and end-stage liver disease requiring liver transplantation. The disease can recur after transplant. Better understanding of pathogenic mechanisms and better treatment modalities are needed to improve the prognosis of this invalidating hepatic disorder.

Serum IgG4 cut-off of 70 mg/dL is associated with a shorter time to cirrhosis decompensation and liver transplantation in primary sclerosing cholangitis patients

BACKGROUND

Primary sclerosing cholangitis (PSC) is an immune-mediated biliary disorder of unknown etiology with no effective treatment. The purpose of this study was to better prognosticate the development of cirrhosis, decompensation, and requirement for liver transplantation (LT) in PSC patients based on serum immunoglobulin G4 (IgG4) levels.

METHODS

A retrospective chart review was conducted on PSC patients seen at the University of Alberta Hospital between 2002 and 2017. PSC patients were categorized as high IgG4 group (≥70 mg/dL) or normal IgG4 group (<70 mg/dL). Laboratory parameters, clinical characteristics, and outcomes were compared between the groups.

RESULTS

One hundred and ten patients were followed over a mean period of 7.3 (SD 5) years. Seventy-two patients (66%) were male, the mean age at diagnosis of PSC was 35 (SD 15) years, and inflammatory bowel disease (IBD) was present in 80 patients (73%). High IgG4 levels were found in 37 patients (34%). PSC patients with high IgG4 had a shorter mean cholangitis-free survival time (5.3 versus 10.4 years, p = 0.02), cirrhosis-free survival time (8.7 versus 13.0 years, p = 0.02), and LT-free survival time (9.3 years versus 18.9 years, p <0.001). IgG4 ≥70 mg/dL was independently associated with liver decompensation and LT-free outcomes. A cut-off IgG4 value of ≥70 mg/dL performed better than a cut-off value of ≥140 mg/dL to predict time to LT (area under the curve [AUC] 0.68, p = 0.03, sensitivity 72%, specificity 78%).

CONCLUSIONS

Serum IgG4 ≥70 mg/dL in PSC predicts a shorter time to cirrhosis decompensation and LT.

IgG4-Related Sclerosing Cholangitis: Rarely Diagnosed, but not a Rare Disease

IgG4-related sclerosing cholangitis, a biliary manifestation of an IgG4-related disease, belongs to the spectrum of sclerosing cholangiopathies which result in biliary stenosis. It presents with signs of cholestasis and during differential diagnosis it should be distinguished from cholangiocarcinoma or from other forms of sclerosing cholangitis (primary and secondary sclerosing cholangitis). Despite increasing information and recently established diagnostic criteria, IgG4-related sclerosing cholangitis remains underdiagnosed in routine clinical practice. The diagnosis is based on a combination of the clinical picture, laboratory parameters, histological findings, and a cholangiogram. Increased serum IgG4 levels are nonspecific but are indeed a part of the diagnostic criteria proposed by the Japan Biliary Association and the HISORt criteria for IgG4-SC. High serum IgG4 retains clinical utility depending on the magnitude of elevation. Approximately 90% of patients have concomitant autoimmune pancreatitis, while 10% present with isolated biliary involvement only. About 26% of patients have other organ involvement, such as IgG4-related dacryoadenitis/sialadenitis, IgG4-related retroperitoneal fibrosis, or IgG4-related renal lesions. A full-blown histological finding characterized by IgG4-enriched lymphoplasmacytic infiltrates, obliterative phlebitis, and storiform fibrosis is difficult to capture in practice because of its subepithelial localization. However, the histological yield is increased by immunohistochemistry, with evidence of IgG4-positive plasma cells. Based on a cholangiogram, IgG-4 related sclerosing cholangitis is classified into four subtypes according to the localization of stenoses. The first-line treatment is corticosteroids. The aim of the initial treatment is to induce clinical and laboratory remission and cholangiogram normalization. Even though 30% of patients have a recurrent course, in the literature data, there is no consensus on chronic immunosuppressive maintenance therapy. The disease has a good prognosis when diagnosed early.

Primary sclerosing cholangitis with moderately elevated serum-IgG4 - characterization and outcome of a distinct variant phenotype

BACKGROUND AND AIMS

Immunoglobulin G4-associated cholangitis (IAC) is characterized by distinctly elevated immunoglobulin G4 in serum (sIgG4) and responds well to corticosteroid therapy. Primary Sclerosing Cholangitis (PSC) is a progressive liver disease without causal treatment options usually not responding to immunosuppression. Increased serum levels of sIgG4 in patients with PSC, that do not meet criteria of IAC, have been reported in 10%-25%. Therefore, we aimed to characterize this subgroup of patients in a retrospective, multicenter study.

METHODS

sIgG4 values of 289 patients with PSC from three German university hospitals were analysed. Patients with elevated sIgG4 levels were identified and further characterized by clinical and biochemical parameters and by cholangiographic presentation. Clinical endpoints, death and liver transplantation were compared between groups. Parameters associated with outcome were identified with Cox regression analysis.

RESULTS

14.5% of patients with PSC showed increased sIgG4 levels (PSC-IgG4), presented with significantly higher (P < .02) albumin, aspartate-aminotransferase, bilirubin and alkaline phosphatase and had a significant lower prevalence of a concomitant autoimmune hepatitis (P = .025). Cholangiogram obtained via ERC showed extrahepatic dominant strictures more often in the PSC-IgG4 subgroup (P = .047). The disease severity models Amsterdam-Oxford-Score (P = .018) and Mayo-Risk-Score (P = .025) predicted lower survival rates for the PSC-IgG4 subgroup. Transplant-free survival after first diagnosis of PSC was shorter in patients with elevated sIgG4 (11.6 vs 15.1 years, P = .001).

CONCLUSION

Patients with PSC and elevated sIgG4 should be considered as a distinct subgroup, characterized by different clinical and cholangiographical features and are associated with an inferior outcome.

Diagnosing Biliary Strictures: Distinguishing IgG4-Related Sclerosing Cholangitis From Cholangiocarcinoma and Primary Sclerosing Cholangitis

Biliary strictures caused by inflammation or fibrosis lead to jaundice and cholangitis which often make it difficult to distinguish malignant strictures. In cases when malignancy cannot be excluded, surgery is often performed. The concept of immunoglobulin G4 (IgG4)-related sclerosing cholangitis (SC) as a benign biliary stricture was recently proposed. The high prevalence of the disease in Asian countries has resulted in multiple diagnostic and treatment guidelines; however, there is need to formulate a standardized diagnostic strategy among various countries considering the utility, invasiveness, and cost-effectiveness. We evaluated accuracies of various diagnostic modalities for biliary strictures comparing pathology in the Delphi meetings which were held in Rochester, MN. The diagnostic utility for each modality was graded according to the experts, including gastroenterologists, endoscopists, radiologists, and pathologists from the United States and Japan. Diagnostic utility of 10 modalities, including serum IgG4 level, noninvasive imaging, endoscopic ultrasound, endoscopic retrograde cholangiopancreatography-related diagnostic procedures were advocated and the reasons were specified. Serum IgG4 level, noninvasive imaging, diagnostic endoscopic ultrasound and intraductal ultrasonography under endoscopic retrograde cholangiopancreatography were recognized as useful modalities for the diagnosis. The information in this article will aid in the diagnosis of biliary strictures particularly for distinguishing IgG4-SC from cholangiocarcinoma and/or primary SC.

Recent advances in the treatment of primary sclerosing cholangitis

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

Review of primary sclerosing cholangitis with increased IgG4 levels

Primary sclerosing cholangitis (PSC) is a chronic progressive liver disease. Sub-types 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 PubMed, 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 PSC-normal 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.

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

New British Society of Gastroenterology/UK-PSC guidelines have recently discussed the current state-of-the-art on primary sclerosing cholangitis and outlined key elements for the management of this disease. The current lack of effective pharmacological treatments to prevent progression of liver fibrosis to cirrhosis limits our ability to modify the natural history of the disease. However, a personalised approach and structured follow-up could allow earlier diagnosis and management of complications and favour access to liver transplantation, which remains the only available treatment. Our commentary overviews the updates and summarises the key recommendations of the recent guidelines for the management of primary sclerosing cholangitis.

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

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

Preventative care in cholestatic liver disease: Pearls for the specialist and subspecialist

Cholestatic liver diseases (CLDs) encompass a variety of disorders of abnormal bile formation and/or flow. CLDs often lead to progressive hepatic insult and injury and following the development of cirrhosis and associated complications. Many such complications are clinically silent until they manifest with severe sequelae, including but not limited to life-altering symptoms, metabolic disturbances, cirrhosis, and hepatobiliary diseases as well as other malignancies. Primary sclerosing cholangitis (PSC) and primary biliary cholangitis (PBC) are the most common CLDs, and both relate to mutual as well as unique complications. This review provides an overview of PSC and PBC, with a focus on preventive measures aimed to reduce the incidence and severity of disease-related complications.

Factors Associated With Outcomes of Patients With Primary Sclerosing Cholangitis and Development and Validation of a Risk Scoring System

We sought to identify factors that are predictive of liver transplantation or death in patients with primary sclerosing cholangitis (PSC), and to develop and validate a contemporaneous risk score for use in a real-world clinical setting. Analyzing data from 1,001 patients recruited to the UK-PSC research cohort, we evaluated clinical variables for their association with 2-year and 10-year outcome through Cox-proportional hazards and C-statistic analyses. We generated risk scores for short-term and long-term outcome prediction, validating their use in two independent cohorts totaling 451 patients. Thirty-six percent of the derivation cohort were transplanted or died over a cumulative follow-up of 7,904 years. Serum alkaline phosphatase of at least 2.4 × upper limit of normal at 1 year after diagnosis was predictive of 10-year outcome (hazard ratio [HR] = 3.05; C = 0.63; median transplant-free survival 63 versus 108 months; P < 0.0001), as was the presence of extrahepatic biliary disease (HR = 1.45; P = 0.01). We developed two risk scoring systems based on age, values of bilirubin, alkaline phosphatase, albumin, platelets, presence of extrahepatic biliary disease, and variceal hemorrhage, which predicted 2-year and 10-year outcomes with good discrimination (C statistic = 0.81 and 0.80, respectively). Both UK-PSC risk scores were well-validated in our external cohort and outperformed the Mayo Clinic and aspartate aminotransferase-to-platelet ratio index (APRI) scores (C statistic = 0.75 and 0.63, respectively). Although heterozygosity for the previously validated human leukocyte antigen (HLA)-DR*03:01 risk allele predicted increased risk of adverse outcome (HR = 1.33; P = 0.001), its addition did not improve the predictive accuracy of the UK-PSC risk scores. Conclusion: Our analyses, based on a detailed clinical evaluation of a large representative cohort of participants with PSC, furthers our understanding of clinical risk markers and reports the development and validation of a real-world scoring system to identify those patients most likely to die or require liver transplantation.

Evolving role of magnetic resonance techniques in primary sclerosing cholangitis

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

Clinical practice guidelines for IgG4-related sclerosing cholangitis

IgG4‐related sclerosing cholangitis (IgG4‐SC) is a distinct type of cholangitis frequently associated with autoimmune pancreatitis and currently recognized as a biliary manifestation of IgG4‐related disease. Although clinical diagnostic criteria of IgG4‐SC were established in 2012, differential diagnosis from primary sclerosing cholangitis and cholangiocarcinoma is sometimes difficult. Furthermore, no practical guidelines for IgG4‐SC are available. Because the evidence level of most articles retrieved through searching the PubMed, Cochrane Library, and Igaku Chuo Zasshi databases was below C based on the systematic review evaluation system of clinical practice guidelines MINDS 2014, we developed consensus guidelines using the modified Delphi approach. Three committees (a guideline creating committee, an expert panelist committee for rating statements according to the modified Delphi method, and an evaluating committee) were organized. Eighteen clinical questions (CQs) with clinical statements were developed regarding diagnosis (14 CQs) and treatment (4 CQs). Recommendation levels for clinical statements were set using the modified Delphi approach. The guidelines explain methods for accurate diagnosis, and safe and appropriate treatment of IgG4‐SC.

Design and Endpoints for Clinical Trials in Primary Sclerosing Cholangitis

Primary sclerosing cholangitis (PSC) is a rare and chronic liver disease for which there is no effective therapy. Interest has grown in developing treatments for this condition, with several agents proposed as potential therapies. However, there is a lack of clarity about how to measure clinical benefit in trials involving patients with this complex and rare disease. This article reviews regulatory information, the available literature on natural history, as well as potential candidate clinical and surrogate endpoints for PSC. (Hepatology 2018; 00:000-000).

Clinical guidelines for primary sclerosing cholangitis 2017

BACKGROUND

Primary sclerosing cholangitis (PSC) is relatively rare disease and pathogenesis and methods of treatments were still not established. Then, we had conducted the making clinical guidelines to manage patients with PSC based on the literature review and expert opinions. These clinical guidelines were made for the medical doctors on the management of PSC, except child case of PSC.

METHODS

We had employed modified Delphi method. The production committee decided guidelines, strength of recommendations and evidence level after reviewed literatures systematically, and The Expert panel evaluated those. The Scientific Committee of the Japan Biliary Association (JBA) evaluated revised guidelines, and the Public comments were collected on web site of JBA.

RESULTS

We had made 16 guidelines about epidemiology/pathophysiology, diagnostics, therapy and prognosis. Also, we had made both diagnostic and therapeutic flow chart.

CONCLUSIONS

We hope that these guidelines will contribute to the improvement and development of the medical care of PSC.

Endoscopic management of primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is a rare but clinically important cholestatic liver disease. Histopathologically and cholangiographically, PSC is characterized by intra- and/or extra-hepatic bile duct inflammation and fibro-obliteration, which ultimately leads to biliary cirrhosis and related sequelae, including development of hepatobiliary and colorectal carcinomata. PSC can be diagnosed at essentially any age and carries a median survival of 15-20 years, regardless of age at diagnosis, and is a foremost risk factor for cholangiocarcinoma. Given the chronic and progressive nature of PSC, its inherent association with both neoplastic and non-neoplastic biliary tract complications, and the lack of effective pharmacotherapies, alimentary and biliary tract endoscopy plays a major role in the care of patients with PSC. Areas covered: Here, we provide a narrative review on endoscopic management of PSC, including established and evolving applications to the diagnosis and treatment of both its benign and malignant complications. Expert commentary: Due to the rarity of PSC and the considerable patient-years required to rigorously study major endpoints, there remains a paucity of high-quality evidence regarding its management. As the advanced endoscopic repertoire expands, so has the interest in developing best practices in PSC, which we discuss herein.

The significance of serum IgG4 and CA19-9, autoantibodies in diagnosis and differential diagnosis of IgG4-related sclerosing cholangitis

OBJECTIVE

To investigate the value of serum levels of IgG₄ and CA19-9, and autoantibodies in the diagnosis of IgG₄-related sclerosing cholangitis (IgG₄-SC).

METHODS

We detected the serum IgG₄ and CA19-9 of 45 IgG₄-SC patients, 173 non-IgG₄-SC patients and 48 healthy controls by immunoassay and chemiluminescence, respectively, with antinuclear antibody (ANA), anti-neutrophil antibody (ANCA), anti-smooth muscle antibody (SMA) and anti-mitochondrial antibody (AMA) level detected by indirect immunofluorescence. Then analyze the detection results.

RESULTS

(1) The positive rates of ANA, ANCA, SMA and AMA in patients with IgG₄-SC were 40%, 6.67%, 0 and 2.22%. Among them, the positive rate of ANA was significantly higher than that of the healthy control group (p < .01), and the positive rate of ANA, ANCA, SMA and AMA were significantly different from that of the non-IgG₄-SC group (p < .05). (2) Serum levels of IgG₄ and CA19-9 increased significantly in patients with IgG₄-SC compared with the healthy controls (p < .01). The areas under the ROC curve (AUC) of IgG₄ and CA19-9 were 0.9750 and 0.6498, respectively (p < .05).

CONCLUSION

The high levels of serum IgG₄ and CA19-9, and autoantibodies detections are of great important clinical value in diagnosis and differential diagnosis of IgG₄-SC.

Localized autoimmune pancreatitis mimicking pancreatic cancer: Case report and literature review

Autoimmune pancreatitis (AP) is a rare autoimmune pancreatic manifestation of systemic immunoglobulin G4 (IgG4)-related sclerosing disease. Distinguishing between AP and pancreatic cancer is crucial because the clinical courses, treatments, and prognoses of these two disease entities are quite different. We herein report a case involving a 52-year-old man with subacute epigastralgia who visited our hospital for evaluation of a suspicious pancreatic mass found during esophagogastroduodenoscopy. Enhanced computed tomography (CT) revealed an enlarged lesion in the pancreatic head with encasement of hepatic vessels. The lesion also exhibited increased ¹⁸F-fluorodeoxyglucose accumulation on positron emission tomography/CT imaging, which was highly suggestive of pancreatic cancer. After open biopsy, morphologic examination showed an inflammatory infiltrate in the pancreas, which was compatible with chronic sclerotic pancreatitis. Further laboratory tests revealed an elevated serum IgG4 level, and the diagnosis of sclerotic pancreatitis was then confirmed. After corticosteroid treatment, the pancreatic lesion showed shrinkage on follow-up CT, and the serum IgG4 titer decreased to the normal range. This case suggests that clinicians should be familiar with the clinical presentations and diagnostic criteria of AP versus pancreatic cancer. An awareness of the differences between these diseases may avoid misdiagnosis and unnecessary surgical intervention.

Development of a scoring system for differentiating IgG4-related sclerosing cholangitis from primary sclerosing cholangitis

BACKGROUND

Recent research has shown that a substantial number of patients with primary sclerosing cholangitis (PSC) can also have elevated serum/tissue IgG4. The aim of our study was to develop a simple scoring system for the discrimination of IgG4-related sclerosing cholangits (IgG4-SC) from PSC.

METHODS

Patients with IgG4-SC (n = 39) and PSC (n = 76) who had intrahepatic/hilar strictures were included. Candidate-differentiating variables included patient age, other organ involvement (OOI), inflammatory bowel disease, serum IgG4, and cholangiographic features. A scoring system was developed on the basis of these variables, and its performance was internally validated using a bootstrapping-based method.

RESULTS

The scoring system in the final model included age (<30 years, 0 points; 30-39 years, 1 point; 40-49 years, 2 points; 50-59 years, 3 points; ≥60 years, 4 points), OOI (no, 0 points; yes, 3 points), and beaded appearance (yes, 0 points; no, 2 points). The patients were classified according to their total score into three categories: 0-4 points, probable PSC; 5-6 points, indicating diagnostic steroid trial; 7-9 points, probable IgG4-SC. The discrimination between IgG4-SC and PSC using the scoring system was excellent (area under the receiver operating characteristic curve, 0.986).

CONCLUSIONS

A reliable differentiation of IgG4-SC from PSC can be made using the scoring system presented here. We suggest the diagnosis of IgG4-SC at a cutoff of 7 points or higher and the indication of diagnostic steroid trial at 5 or 6 points. External validation of our scoring system is warranted.

No negative impact of serum IgG4 levels on clinical outcome in 435 patients with primary sclerosing cholangitis from Japan

BACKGROUND

Several studies have demonstrated that elevated serum IgG4 levels are associated with poor outcomes of primary sclerosing cholangitis (PSC), but the impact of serum IgG4 levels on PSC remains controversial. In this study, we aimed to determine prognostic factors of patients with PSC and to investigate the association between serum IgG4 levels and the clinical features and prognosis of PSC in a Japanese cohort.

METHODS

We retrospectively analyzed follow-up data for 435 patients with PSC (UMIN000018438). Patients with distinct etiologies of sclerosing cholangitis including IgG4-related sclerosing cholangitis (IgG4-SC) were excluded from this study.

RESULTS

Serum IgG4 levels were tested at the time of diagnosis in 216 of 435 patients with PSC, and were elevated in 27 patients (>134 mg/dl, 12.5%). Clinical features at diagnosis were comparable between patients with normal and elevated serum IgG4 levels, with the exception of serum albumin. The overall and liver-transplantation free survival rate was comparable between the groups. Multivariate analysis indicated that age, albumin, and bilirubin, but not IgG4, at the time of diagnosis affected PSC prognosis.

CONCLUSIONS

The current study showed that serum IgG4 levels at diagnosis do not affect PSC prognosis in a Japanese cohort that excluded patients with IgG4-SC.

Imaging of autoimmune biliary disease

Autoimmune biliary diseases are poorly understood but important to recognize. Initially, autoimmune biliary diseases are asymptomatic but may lead to progressive cholestasis with associated ductopenia, portal hypertension, cirrhosis, and eventually liver failure. The three main forms of autoimmune biliary disease are primary biliary cirrhosis, primary sclerosing cholangitis, and IgG4-associated cholangitis. Although some overlap may occur between the three main autoimmune diseases of the bile ducts, each disease typically affects a distinct demographic group and requires a disease-specific diagnostic workup. For all the autoimmune biliary diseases, imaging provides a means to monitor disease progression, assess for complications, and screen for the development of hepatobiliary malignancies that are known to affect patients with these diseases. Imaging is also useful to suggest or corroborate the diagnosis of primary sclerosing cholangitis and IgG4-associated cholangitis. We review the current literature and emphasize radiological findings and considerations for these autoimmune diseases of the bile ducts.

Primary sclerosing cholangitis associated with inflammatory bowel disease: an update

Primary sclerosing cholangitis (PSC) is a chronic progressive disease, usually associated with underlying inflammatory bowel diseases (IBDs), with a prevalence of 60-80% in western countries. Herein, we review the current knowledge about the association between PSC and IBD in terms of clinical approach and long-term patient management. A PubMed search was conducted for English-language publications from 2000 through 2015 using the following keywords: primary sclerosing cholangitis, inflammatory bowel disease, ulcerative colitis, Crohn's disease, diagnosis, therapy, follow-up, and epidemiology. In terms of diagnosis, liver function tests and histology are currently used. The medical treatment options for PSC associated with IBD do not differ from the cases of PSC alone, and include ursodeoxycholic acid and immunosuppressive agents. These treatments do not seem to improve survival, even if ursodeoxycholic acid given at low doses may be chemopreventive against colorectal cancer (CRC). Liver transplantation is the only potential curative therapy for PSC with reported survival rates of 85 and 70% at 5 and 10 years after transplant; however, there is a risk for PSC recurrence, worsening of IBD activity, and de-novo IBD occurrence after liver transplantation. PSC-IBD represents an important public health concern, especially in view of the increased risk for malignancy, including CRC. Long-life annual surveillance colonoscopy is usually recommended, although the exact timescale is still unclear. Further studies are required both to clarify whether annual colonoscopy is cost-effective, especially in younger patients, and to identify potential pharmaceutical agents and genetic targets that may retard disease progression and protect against CRC.

Primary Sclerosing Cholangitis: Multiple Phenotypes, Multiple Approaches

Primary sclerosing cholangitis (PSC) is a heterogeneous, idiopathic, inflammatory disorder frequently associated with inflammatory bowel diseases. PSC patients may be classified into several subphenotypes. Investigations of pediatric, nonwhite, and female PSC patients have revealed distinguishing features. The natural history of PSC is variable in progression with numerous possible clinical outcomes. PSC patients may suffer bacterial cholangitis, cholangiocarcinoma, or colorectal adenocarcinoma. Treatments focusing on bile acid therapy and immunosuppression have not proven beneficial. Interest in PSC and international collaboration has led to improved understanding of the heterogeneity and the genetic structure and introduced possible effective therapeutics.

IgG4-Related Disease of the Gastrointestinal Tract: A 21st Century Chameleon

CONTEXT

Immunoglobulin G4 (IgG4)-related disease is a systemic fibroinflammatory disease capable of affecting virtually any organ. Although the pancreas and hepatobiliary system are commonly affected, involvement of the tubular gut is unusual. The pancreatic manifestations of this disease (autoimmune pancreatitis) often mimic pancreatic carcinoma, whereas the hepatobiliary manifestations are mistaken for cholangiocarcinoma or primary sclerosing cholangitis. The characteristic histologic features include a dense lymphoplasmacytic infiltrate, storiform-type fibrosis, and obliterative phlebitis. An increase in IgG4(+) plasma cells and an IgG4 to IgG ratio of more than 40% are considered obligatory components of the diagnostic algorithm.

OBJECTIVE

To review the challenges associated with the diagnosis of IgG4-related disease of the gastrointestinal tract.

DATA SOURCES

A review of pertinent literature, along with the author's personal experience, based on institutional and consultation materials.

CONCLUSION

The complete spectrum of histologic changes is seldom captured in a biopsy specimen, and thus, the histopathology findings are best interpreted within the overall clinical context. Increased IgG4(+) plasma cells are identified in a variety of benign and malignant diseases of the gastrointestinal tract.

Current Concepts in Primary Biliary Cirrhosis and Primary Sclerosing Cholangitis

Primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) are chronic, cholestatic diseases of the liver with common clinical manifestations. Early diagnosis and treatment of PBC slows progression and decreases the need for transplant. However, one-third of patients will progress regardless of treatment. Bilirubin <1.0 and alkaline phosphatase <2.0 x the upper limit of normal at 1 year after treatment appear to predict 10-year survival. Ursodeoxycholic acid (UDCA) is the recommended treatment for PBC, and recent studies with obeticholic acid showed promising results for UDCA non-responders. Unlike PBC, no therapy has been shown to alter the natural history of PSC. The recommended initial diagnostic test for PSC is magnetic resonance cholangiopancreatography, typically showing bile duct wall thickening, focal bile duct dilatation, and saccular dilatation of the intra- and/or extrahepatic bile ducts. Immunoglobulin 4-associated cholangitis must be excluded when considering the diagnosis of PSC, to allow for proper treatment, and monitoring of disease progression. In addition to the lack of therapy, PSC is a pre-malignant condition and close surveillance is indicated.

Recent Advances in Autoimmune Pancreatitis

Autoimmune pancreatitis (AIP) is a form of chronic pancreatitis that is characterized clinically by frequent presentation with obstructive jaundice, histologically by a dense lymphoplasmacytic infiltrate with fibrosis, and therapeutically by a dramatic response to corticosteroid therapy. Two distinct diseases, type 1 and type 2 AIP, share these features. However, these 2 diseases have unique pancreatic histopathologic patterns and differ significantly in their demographic profiles, clinical presentation, and natural history. Recognizing the popular and long-standing association of the term "AIP" with what is now called "type 1 AIP," we suggest using "AIP" solely for type 1 AIP and to acknowledge its own distinct disease status by using "idiopathic duct-centric chronic pancreatitis" (IDCP) for type 2 AIP. AIP is the pancreatic manifestation of immunoglobulin G4-related disease (IgG4-RD). The etiopathogenesis of AIP and IgG4-RD is largely unknown. However, the remarkable effectiveness of B-cell depletion therapy with rituximab in patients with AIP and IgG4-RD highlights the crucial role of B cells in its pathogenesis. IDCP is less commonly recognized, and little is known about its pathogenesis. IDCP has no biomarker but is associated with inflammatory bowel disease in ~25% of patients. Recently, the international consensus diagnostic criteria for AIP identified combinations of features that are diagnostic of both diseases. Both AIP and IDCP are corticosteroid responsive; however, relapses are common in AIP and rare in IDCP. Therefore, maintenance therapy with either an immunomodulator (eg, azathioprine, 6-mercaptopurine, or mycophenolate mofetil) or rituximab is often necessary for patients with AIP. Long-term survival is excellent for both patients with AIP and patients with IDCP.

Primary sclerosing cholangitis: a clinical update

INTRODUCTION

Primary sclerosing cholangitis (PSC) is a progressive cholestatic disorder that ultimately can lead to cirrhosis, liver failure, malignancy and death. It is strongly associated with inflammatory bowel disease (IBD), and though a rare disease, its incidence is increasing. There are no proven medical therapies for PSC.

SOURCES OF DATA

Ovid Medline was utilised to search for articles with keywords 'sclerosing cholangitis' and 'cholangiocarcinoma' and containing titles 'primary sclerosing cholangitis', and references of these papers were cross-referenced for further relevant manuscripts.

AREAS OF AGREEMENT

PSC is a rare disease, and there is a strong association with risk loci within the major histocompatibility complex and other genes common to other autoimmune diseases. PSC is a premalignant condition, associated with higher rates of hepatobiliary and colorectal cancer in patients with ulcerative colitis (UC).

AREAS OF CONTROVERSY

The pathogenesis is unclear, and competing theories exist surrounding toxic bile acids, enhanced homing of particular T cells from the gut to the liver and increased passage of toxins to the liver through a permeable bowel wall. It is unclear whether the higher rate of colonic cancer in PSC/UC occurs in PSC/Crohn's disease. Ursodeoxycholic acid therapy reduces liver enzymes but has not been shown to improve survival. It may reduce the prevalence of bowel cancer.

GROWING POINTS

Recent genetic studies have revealed new risk loci, pointing to the importance of the immune system and its interaction with the biome.

AREAS TIMELY FOR DEVELOPING RESEARCH

On the basis of the genetic studies discussed earlier, novel agents are being developed and trialled in the treatment of PSC.

ACG Clinical Guideline: Primary Sclerosing Cholangitis

Primary sclerosing cholangitis is a chronic cholestatic liver disease that can shorten life and may require liver transplantation. The cause is unknown, although it is commonly associated with colitis. There is no approved or proven therapy, although ursodeoxycholic acid is used by many on an empiric basis. Complications including portal hypertension, fat-soluble vitamin deficiency, metabolic bone diseases, and development of cancers of the bile duct or colon can occur.

Biomarkers for disease progression of primary sclerosing cholangitis

PURPOSE OF REVIEW

Primary sclerosing cholangitis (PSC) is a chronic cholestatic liver disease of unknown origin. There is no medical treatment of proven benefit on survival; once patients have progressed to end-stage liver disease, the only treatment option is liver transplantation.

RECENT FINDINGS

Over the last years, some progress has been made in identifying biomarkers of PSC disease progression. Categories that can be distinguished include clinical and biochemical biomarkers, histology, imaging, prognostic modelling and genetics. With this review, we summarize biomarkers for progression of PSC from these six categories, which have been studied to date.

SUMMARY

Biomarkers for the progression of PSC disease course can be used for several purposes. First of all, they can be implemented as surrogate endpoints for clinical trials. Second, biomarkers of disease progression form the basis of prognostic modelling, which is needed for proper patient counselling and management. Lastly, these biomarkers may yield a better understanding of PSC pathogenesis.

IgG4-related sclerosing cholangitis in the absence of autoimmune pancreatitis mimicking extrahepatic cholangiocarcinoma

AIMS

IgG4-related sclerosing cholangitis in extrahepatic bile ducts in the absence of autoimmune pancreatitis (AIP) is rare and is poorly studied. Herein, we present the clinicopathological features of four cases of IgG4-related sclerosing cholangitis.

METHODS AND RESULTS

The clinicopathological features of IgG4-related sclerosing cholangitis were compared with those of IgG4-related sclerosing cholangitis with AIP (n = 7), extrahepatic cholangiocarcinoma (n = 29), primary sclerosing cholangitis (n = 40), and secondary sclerosing cholangitis (n = 12). Several histomorphologic features distinguish IgG4-related sclerosing cholangitis, including a marked degree of bile duct injury, a higher percentage of lymphoid follicle formation, a higher percentage of perineuritis, and a more diffuse and dense lymphoplasmacytic infiltrate. All four cases of IgG4-related sclerosing cholangitis occurred exclusively in males. Of these cases, none had IgG4 serology checked preoperatively, and all had a preoperative diagnosis of extrahepatic cholangiocarcinoma. Clinical follow-up was available in 2 patients with a mean time of 11 months. Follow-up confirmed the benign course of the disease as the patients showed no evidence of relapse. IgG4-related conditions, including sclerosing cholecystitis and retroperitoneal fibrosis, were noted in three patients.

CONCLUSIONS

IgG4-related sclerosing cholangitis in the absence of AIP presents as a distinct and under-recognized disease that mimics extrahepatic cholangiocarcinoma clinically. Awareness of this entity is essential to avoid erroneously diagnosing malignancy. The current threshold of 10 IgG4-positive plasma cells/high-power field (HPF) in the biopsy is not specific enough to exclude cholangiocarcinoma. Therefore, we suggest the diagnostic cut-off to be 50 IgG4-positive plasma cells/HPF in the biopsy.

Lymphoplasmacytic sclerosing pancreatitis without IgG4 tissue infiltration or serum IgG4 elevation: IgG4-related disease without IgG4

Type 1 autoimmune pancreatitis can be diagnosed by and is synonymous with its pathognomonic histopathologic appearance called lymphoplasmacytic sclerosing pancreatitis. Type 1 autoimmune pancreatitis, also called IgG4-related pancreatitis, is the pancreatic manifestation of IgG4-related disease. However, the role of IgG4 in the pathogenesis of IgG4-related disease is unclear. We describe patients with LPSP without serum or tissue IgG4 abnormalities. From the Mayo Clinic database of autoimmune pancreatitis patients, we identified three patients with histologically confirmed type 1 autoimmune pancreatitis (lymphoplasmacytic sclerosing pancreatitis) who had normal serum IgG4 and no increase in IgG4-positive plasma cells in tissue. We reviewed original clinical records and pathologic specimens, and describe the clinical and histologic features of these three patients. All patients (age/gender: 63/F, 70/M and 68/M) had normal serum IgG and IgG4 levels, and multiple sections of pancreatic histology did not show increased IgG4-positive plasma cells. Two patients were diagnosed retrospectively following pancreatic surgery, one relapsed in another organ and one has remained relapse free. Another patient was diagnosed by pancreatic core biopsy and has suffered multiple relapses that have been controlled by rituximab. These cases highlight the fact that although the currently agreed upon name for type 1 autoimmune pancreatitis is IgG4-related pancreatitis, serum and tissue IgG4 abnormalities are best considered characteristic, but not essential for the diagnosis of this enigmatic condition.