Clinical Features, Response to Treatment, and Outcomes of IgG4-Related Sclerosing Cholangitis

Biliary fibrosis is an important but neglected pathological feature in hepatobiliary disorders: from molecular mechanisms to clinical implications

Fibrosis resulting from pathological repair secondary to recurrent or persistent tissue damage often leads to organ failure and mortality. Biliary fibrosis is a crucial but easily neglected pathological feature in hepatobiliary disorders, which may promote the development and progression of benign and malignant biliary diseases through pathological healing mechanisms secondary to biliary tract injuries. Elucidating the etiology and pathogenesis of biliary fibrosis is beneficial to the prevention and treatment of biliary diseases. In this review, we emphasized the importance of biliary fibrosis in cholangiopathies and summarized the clinical manifestations, epidemiology, and aberrant cellular composition involving the biliary ductules, cholangiocytes, immune system, fibroblasts, and the microbiome. We also focused on pivotal signaling pathways and offered insights into ongoing clinical trials and proposing a strategic approach for managing biliary fibrosis-related cholangiopathies. This review will offer a comprehensive perspective on biliary fibrosis and provide an important reference for future mechanism research and innovative therapy to prevent or reverse fibrosis.

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.

Malignancy and mass-forming phenotypes of IgG4-related disease: a challenging diagnosis

Mass-forming phenotypes of IgG4-related disease (IgG4-RD) mimic malignancy and histological confirmation can be challenging. A woman in her 70s with HIV infection presented with painless obstructive jaundice and weight loss. Magnetic resonance imaging was suggestive of unresectable cholangiocarcinoma. Tumour markers and serum IgG4 were normal. Percutaneous liver biopsy was consistent with IgG4-RD inflammatory pseudotumour, with complete response to glucocorticoid therapy. Two years later, a new episode of obstructive jaundice occurred, with CT showing a solid lesion in the head of the pancreas with double duct sign and encasement of the portal vein. Re-induction therapy was tried without response. Fine-needle biopsy was consistent with pancreatic cancer. Supportive care was offered and the patient died 8 months later, with no signs of disease progression on subsequent imaging. We discuss the challenges of IgG4-RD diagnosis and treatment and the differential diagnosis between mass-forming phenotypes and malignancy, highlighting the difficulties in managing such patients.

Case report: Isolated immunoglobulin G4-related sclerosing cholangitis misdiagnosed as hilar cholangiocarcinoma

Background

Immunoglobulin G4-related sclerosing cholangitis (IgG4-SC) is frequently accompanied with type 1 autoimmune pancreatitis (AIP). Isolated IgG4-SC which is not accompanied with AIP is uncommon in clinical practice, and its manifestations are similar to those of hilar cholangiocarcinoma.

Case presentation

A 55-year-old male presented with persistent aggravation of icteric sclera and skin. He was initially diagnosed with hilar cholangiocarcinoma and underwent surgery. However, positive IgG4 plasma cells were found in the surgical specimens. Thus, a pathological diagnosis of IgG4-SC was established. After that, steroid therapy was given and initially effective. But he was steroid dependent, and then received rituximab therapy twice. Unfortunately, the response to rituximab therapy was poor.

Conclusion

It is crucial to differentiate isolated IgG4-SC from hilar cholangiocarcinoma to avoid unnecessary surgery. Future studies should further explore effective treatment strategy in patients who do not respond to steroids therapy. It is also required to develop novel and accurate diagnostic approaches to avoid unnecessary surgical procedures.

An atypical case of isolated immunoglobulin G4-related sclerosing cholangitis with a cholangiogram resembling primary sclerosing cholangitis

An asymptomatic 77-year-old man with intrahepatic bile duct dilation was referred to our hospital. Cholangiography revealed alternations between strictures and dilated segments from the right and left hepatic ducts to the lower bile ducts, with findings of a pruned tree, beaded, shaggy appearance, and diverticulum-like outpouching. Histopathology revealed abundant immunoglobulin G4 (IgG4)-positive plasma cells (> 10 per high-power field) with an IgG4/IgG-positive cell ratio of 40-50%. After 2 weeks of steroid therapy, the cholangiography markedly improved. Because the cholangiographic findings resembled those of primary sclerosing cholangitis, steroid therapy proved useful in differentiating IgG4-related sclerosing cholangitis from primary sclerosing cholangitis.

Clinical patterns and risk factors for multiorgan involvement in IgG4-Related disease patients

Background

IgG4-related disease with multiorgan involvement predicts higher disease activity, thus, it is necessary to identify whether IgG4-related disease involves multiple organs at the early stage. To further clarify the clinical characteristics and risk factors for IgG4-related disease with multiorgan involvement, we conducted an observational study.

Methods

We retrospectively analysed the clinical data of 160 patients who were primarily diagnosed with IgG4-related disease at the First Affiliated Hospital of Zhengzhou University from January 2015 to January 2021. According to the number of involved organs, patients were divided into two groups: multiorgan involvement and nonmultiorgan involvement. Patients were divided into a multiorgan group and a nonmultiorgan group according to multiple organ involvement.

Results

There were 82 cases identified with multiorgan involvement and 78 cases diagnosed with no multiorgan involvement in this series. Most cases were elderly and male (p > 0.05). The most frequently affected organs in IgG4-RD were the lymph nodes (50.6 %), pancreas (38.7 %) and salivary glands (35.6 %). Multivariate analysis showed that eosinophilia, IgG4>2*ULN, lymph node involvement, salivary gland involvement and lung involvement were independent risk factors for multiorgan involvement (p < 0.05).

Conclusions

The main issues in clinical practice are how to accurately diagnose the disease and screen the more vulnerable organs.

IgG4-related hepatic inflammatory pseudotumor in a patient with serum IgG4-negative type 1 autoimmune pancreatitis

IgG4-related disease (IgG4-RD) can cause heterogeneous lesion in various organs. Serum IgG4 levels are useful in monitoring patients with IgG4-RD; however, when it is negative, more careful observation is required. A 58-year-old woman who had been diagnosed with serum IgG4-negative type 1 autoimmune pancreatitis (AIP) 3 years prior visited our hospital for the evaluation of a liver tumor. She had visited a nearby hospital 1 month prior with complaints of a swelling in her right neck, and histological examinations were suggestive of IgG4-related sialadenitis. A positron emission tomography scan showed fluoro-deoxy-glucose accumulation in her right liver lobe; therefore, she was referred to our hospital. Liver tumor biopsy showed inflammatory cell infiltration and storiform fibrosis, without histological findings indicative of a malignancy. Many IgG4-positive cells were detected in immunostaining; thus, an IgG4-related hepatic inflammatory pseudo-tumor was diagnosed. After increasing in steroid dosage, the patient remained recurrence-free with 2 years. To our knowledge, this is the first report of mass-forming IPT for serum IgG4-negative type 1 AIP. Occasionally, IgG4-related IPT may appear in the periphery of the liver, and serum IgG4-negative cases should be more carefully observed because serum IgG4 is not an indicator.

IgG4-related cholangitis - a mimicker of fibrosing and malignant cholangiopathies

IgG4-related cholangitis (IRC) is the major hepatobiliary manifestation of IgG4-related disease (IgG4-RD), a systemic fibroinflammatory disorder. The pathogenesis of IgG4-RD and IRC is currently viewed as multifactorial, as there is evidence of a genetic predisposition while environmental factors, such as blue-collar work, are major risk factors. Various autoantigens have been described in IgG4-RD, including annexin A11 and laminin 511-E8, proteins which may exert a partially protective function in cholangiocytes by enhancing secretion and barrier function, respectively. For the other recently described autoantigens, galectin-3 and prohibitin 1, a distinct role in cholangiocytes appears less apparent. In relation to these autoantigens, oligoclonal expansions of IgG4+ plasmablasts are present in patients with IRC and disappear upon successful treatment. More recently, specific T-cell subtypes including regulatory T cells, follicular T helper 2 cells, peripheral T helper cells and cytotoxic CD8+ and CD4+ SLAMF7+ T cells have been implicated in the pathogenesis of IgG4-RD. The clinical presentation of IRC often mimics other biliary diseases such as primary sclerosing cholangitis or cholangiocarcinoma, which may lead to inappropriate medical and potentially invalidating surgical interventions. As specific biomarkers are lacking, diagnosis is made according to the HISORt criteria comprising histopathology, imaging, serology, other organ manifestations and response to therapy. Treatment of IRC aims to prevent or alleviate organ damage and to improve symptoms and consists of (i) remission induction, (ii) remission maintenance and (iii) long-term management. Glucocorticosteroids are highly effective for remission induction, after which immunomodulators can be introduced for maintenance of remission as glucocorticosteroid-sparing alternatives. Increased insight into the pathogenesis of IRC will lead to improved diagnosis and novel therapeutic strategies in the future.

IgG4-related digestive diseases: diagnosis and treatment

IgG4-related digestive diseases encompass a group of chronic inflammatory disorders characterized by autoimmune reactions and fibrosis affecting multiple digestive organs. These diseases are identified by elevated serum levels of IgG4 and the presence of IgG4-positive plasma cell infiltration in the affected sites, along with storiform fibrosis, obliterative phlebitis, and eosinophilic infiltration. Although extensive research has been conducted, a comprehensive understanding of these conditions remains elusive. Current clinical diagnosis often relies on the application of integrated diagnostic criteria for IgG4-related diseases, combined with specific organ involvement criteria. Distinguishing them from malignancies poses considerable challenges. Moreover, further investigations are required to elucidate the underlying pathogenic mechanisms and explore potential therapeutic interventions. This review provides a systematic classification of IgG4-related digestive diseases while discussing their diagnostic strategies, clinical presentations, and treatment modalities. The comprehensive insights shared herein aim to guide clinicians in their practice and contribute to the advancement of knowledge in this field.

An unusual cause of extrahepatic cholestasis associated with solid liver lesions: a case report

IgG4-related sclerosing cholangitis is a special type of cholangiopathy often associated with autoimmune pancreatitis. In this article, we report an unusual case of IgG4-SC limited to the common hepatic duct and associated with pseudo tumoral liver lesions, but without evidence of pancreatic involvement. Corticosteroid therapy was rapidly effective and allowed normalization of liver tests.

Secondary sclerosing cholangitis and IgG4-sclerosing cholangitis - A review of cholangiographic and ultrasound imaging

Sclerosing cholangitis (SC) represents a spectrum of chronic progressive cholestatic diseases of the intrahepatic and/or extrahepatic biliary system characterized by patchy inflammation, fibrosis, and stricturing. Primary and secondary SC must be distinguished given the different treatment modalities, risks of malignancy, and progression to portal hypertension, cirrhosis, and hepatic failure. This review focuses on secondary SC and the pathogenic mechanisms, risk factors, clinical presentation, and novel imaging modalities that help to distinguish between these conditions. We explore the detailed use of cholangiography and ultrasound imaging techniques.

IgG4-related sclerosing cholangitis, a mimicker of the cholangiocarcinoma: A case report

An 83-year-old-male patient presented with obstructive jaundice, whose imagings were consistent with the cholangiocarcinoma of the distal common bile duct. The tumor markers were within normal limits. IgG4 level was raised; therefore, IgG4-sclerosing cholangitis was made as the provisional diagnosis. Steroid therapy was started to which he responded well.

Comparison of the long-term outcomes between proximal and distal IgG4-related sclerosing cholangitis: A multicenter cohort study

BACKGROUND AND AIMS

Immunoglobulin G4-related sclerosing cholangitis (IgG4-SC) is considered a biliary manifestation of IgG4-related diseases. However, there has been a controversy on the clinical outcomes according to the location of the involved bile duct. We therefore compared the clinical outcomes and long-term prognosis of IgG4-SC with proximal bile duct involvement (proximal IgG4-SC) and IgG4-SC with distal bile duct involvement (distal IgG4-SC).

METHODS

We reviewed the data of patients with IgG4-SC that were prospectively collected at 10 tertiary centers between March 2002 and October 2020. Clinical manifestations, outcomes, association with autoimmune pancreatitis (AIP), steroid-responsiveness, and relapse of IgG4-SC were evaluated.

RESULTS

A total of 148 patients (proximal IgG4-SC, n = 59; distal IgG4-SC, n = 89) were analyzed. The median age was 65 years (IQR, 56.25-71), and 86% were male. The two groups were similar in terms of jaundice at initial presentation (51% vs 65%; P = 0.082) and presence of elevated serum IgG4 (66% vs 70%; P = 0.649). The two groups showed significant differences in terms of steroid-responsiveness (91% vs 100%; P = 0.008), association with AIP (75% vs 99%; P = 0.001), and occurrence of liver cirrhosis (9% vs 1%; P = 0.034). During a median follow-up of 64 months (IQR, 21.9-84.7), the cumulative relapse-free survival was significantly different between the two groups (67% vs 79% at 5 years; P = 0.035).

CONCLUSIONS

Relapse of IgG4-SC frequently occurred during follow-up. Proximal IgG4-SC and distal IgG4-SC had different long-term outcomes in terms of steroid-responsiveness, occurrence of liver cirrhosis, and recurrence. It may be advantageous to determine the therapeutic and follow-up strategies according to the location of bile duct involvement.

Autoimmune pancreatitis: A bibliometric analysis from 2002 to 2022

Background/Objectives

Autoimmune pancreatitis (AIP) is a distinct form of pancreatic inflammatory disease that responds well to glucocorticoid therapy. Knowledge on AIP has rapidly evolved over the past two decades. Based on bibliometric analysis, this study aimed to assess the research status of AIP over the past two decades and determine the research focus and emerging topics.

Methods

AIP-related publications published between January 1, 2002, and June 6, 2022, were retrieved from the Web of Science Core Collection. Bibliometric data were analyzed using HisCite, VOSviewer, CiteSpace, and bibliometrix package. Annual output, leading countries/regions, active institutions and authors, core journals and references, and keywords of AIP were evaluated.

Results

Overall, 1,772 publications were retrieved from 501 journals by 6,767 authors from 63 countries/regions. Japan published articles on AIP the most (n=728, 41.1%), followed by the United States (n=336, 19%), Germany (n=147, 8.3%), China (n=127, 7%), and Italy (n=107, 6%). The top three most prolific authors were Terumi Kamisawa from Tokyo Metropolitan Komagome Hospital (n=117), Kazuichi Okazaki from Kansai Medical University (n=103), and Shigeyuki Kawa from Matsumoto Dental University (n=94). Pancreas was the most productive journal regarding AIP research (n=95), followed by the Journal of Gastroenterology (n=67), Internal Medicine (n=66), Pancreatology (n=63), and World Journal of Gastroenterology (n=62). "Diagnosis" was the most mentioned keyword. "Risk," "malignancy," "outcome," "22-gauge needle," and "fine-needle aspiration" were recognized as emerging topics.

Conclusion

Japan was the leading country in AIP research. Research papers were mainly published in specialized journals. Diagnosis was the research focus. Long-term outcomes and pancreatic tissue acquisition were recognized as research frontiers for AIP.

[Differential diagnosis of IgG4-related disease]

IgG4-related disease is a chronic autoimmune fibro-inflammatory disease characterized by the presence of lymphoplasmacytic infiltrate, storiform fibrosis, obliterating phlebitis, increased number of IgG4+ cells in tissue, and, in most cases, an elevated serum IgG4 level. This disease often affects the pancreas, salivary glands and lymph nodes, but can involve almost any tissue. Its etiology is still unclear, the central role in the pathogenesis belongs to B-lymphocytes, T2-helpers, interleukins 1-β, 4, 5, 10, 13 and tumor growth factor 1-β. The ambiguous clinical picture and frequent simultaneous involvement of several organs make it difficult to diagnose, so biopsy plays a leading role in making a diagnosis. The characteristic microscopic picture, the presence of certain populations of lymphocytes are key criteria in establishing the correct diagnosis.

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.

Management, outcomes and survival of an Australian IgG4-SC cohort: The MOSAIC study

BACKGROUND AND AIMS

IgG4 sclerosing cholangitis (IgG4-SC) is the biliary component of the multisystem IgG4-related disease. We aimed to investigate the clinical features, demographics, treatment response and outcomes of IgG4-SC in a large Australian cohort.

METHODS

We conducted nationwide retrospective cohort via the Australian Liver Association Clinical Trials Network (ALA-CRN). 39 sites were invited to participate. IgG4-SC was defined by the clinical diagnostic criteria established by the Japanese Biliary Association in 2012. Data were collected on patient demographic, clinical and laboratory information, presenting features, response to therapy and clinical outcomes.

RESULTS

67 patients meet inclusion criteria from 22 sites. 76% were male with mean age of 63.3 ± 14.5 years and a median IgG4 level of 3.6 g/L [0.09-67.1]. The most frequent presenting symptom was jaundice (62%) and abdominal pain (42%) and Type 1 biliary stricturing (52%) at the distal common bile duct was the most frequent biliary tract finding. Prednisolone was used as a primary treatment in 61 (91%) and partial or complete response occurred in 95% of subjects. Relapse was common (42%) in those who ceased medical therapy. After a median follow up of 3.9 years there was one hepatocellular carcinoma and no cholangiocarcinomas.

CONCLUSIONS

Our study confirms the preponderance of IgG4-SC in males and highlights the steroid response nature of this condition although relapse is common after steroid cessation. Progression to malignancy was uncommon.

Role of transabdominal ultrasound in the diagnosis of autoimmune pancreatitis

The most important thing in the diagnosis of autoimmune pancreatitis (AIP) is to suspect the possibility of AIP. In the acute phase, diffuse pancreatic enlargement is a highly specific finding of AIP compared to focal enlargement. Though the sensitivity is low, high-frequency transducers can detect the capsule-like rim sign and penetrating duct sign. Those findings are characteristic of AIP and useful for differential diagnosis with pancreatic carcinoma. In focal AIP, both contrast-enhanced US showing iso/hypervascularity and elastography showing increased stiffness not only in the focal enlargement but also in the surrounding parenchyma are also useful for differential diagnosis. Furthermore, changes over time after the two-week steroid trial, such as resolution or measurable reduction in parenchymal enlargement and a decrease in the mean shear-wave velocity on elastography, are also cardinal features of AIP. Since AIP is a pancreatic manifestation in immunoglobulin G4-related disease, evaluation of other organs, including the biliary tract and salivary glands, is particularly useful in focal AIP. A characteristic US finding of bile ducts is three-layered (high-low-high pattern) wall thickening with a markedly thickened middle layer. US can also detect wall thickening of bile ducts, which show no abnormalities on cholangiography. These findings are useful for differential diagnosis with cholangiocarcinoma. Multiple hypoechoic areas in submandibular glands are characteristic US findings of sialadenitis in type 1 AIP, and the sensitivity is higher than that of physical examination. US can further contribute to the diagnosis of AIP by employing elastography and contrast-enhanced US in addition to high-frequency transducers.

Classification and Diagnostic Criteria for IgG4-Related Sclerosing Cholangitis

IgG4-related sclerosing cholangitis (IgG4-SC) can be classified into four types based on cholangiographic findings and regions of biliary stricture. This cholangiographic classification is useful to differentiate IgG4-SC from mimickers including cholangiocarcinoma, primary sclerosing cholangitis, and pancreatic cancer. Autoimmune pancreatitis (AIP) is a valuable clue for the diagnosis of IgG4-SC because the two are frequently found in association with each other. Two sets of diagnostic criteria for IgG4-SC have been proposed. In Japan, the clinical diagnostic criteria 2020 were recently developed. These clinical diagnostic criteria include narrowing of the intrahepatic and/or extrahepatic bile duct, thickening of the bile duct wall, serological findings, pathological findings, other organ involvement, and effectiveness of steroid therapy. When these criteria are applied, IgG4-SC is initially classified as associated or not associated with AIP, and cholangiographic classification is used for differential diagnosis. In most instances, IgG4-SC can be diagnosed on the basis of clinical diagnostic criteria. However, it is challenging to diagnose isolated IgG4-SC or IgG4-SC not associated with AIP. Here, we review the classification and diagnostic criteria for IgG4-SC, specifically focusing on the clinical diagnostic criteria 2020 and a large IgG4-SC case series from a nationwide survey in Japan.

Biliary Strictures: Etiologies and Medical Management

Biliary strictures have several etiologies that can broadly be classified into benign and malignant causes. The clinical presentation is variable with strictures identified incidentally on imaging or during the evaluation of routine laboratory abnormalities. Symptoms and cholangitis lead to imaging that can diagnose biliary strictures. The diagnosis and medical management of biliary strictures will be discussed in this article.

Hidden IgG4-Related Coronary Disease

OBJECTIVES

We present a full autopsy with a focused radiology and pathologic review of the coronary arteries. We hope that the results described in this article will help create better diagnostic measures and prevent future coronary artery vasculitis misdiagnosis.

METHODS

A full autopsy was performed on the body of Dr Myung Choong Yoon, with full consent from the family, within the department of pathology and laboratory medicine at Vancouver General Hospital. Tissue samples from the heart, brain, lungs, and spinal cord were submitted to specialist pathologists for histologic processing.

RESULTS

Cardiac gated computed tomography coronary angiography suggested periarteritis. Coexistent calcified coronary atherosclerosis with linear calcifications was present along the luminal wall, along with coronary artery ectasia. Histologic assessment confirmed features of dense adventitial fibrosis around the coronary arteries, with an exuberant lymphoplasmacytic infiltrate and numerous plasma cells consistent with IgG4-related disease. The media of the coronary arteries was markedly attenuated or completely absent, which likely contributed to the coronary arterial ectasia noted microscopically. These findings confirmed IgG4-related coronary arteritis.

CONCLUSIONS

Coronary periarteritis is an uncommon manifestation of IgG4-related disease established radiographically and later by autopsy.

Endoscopic retrograde cholangiopancreatography and intraductal ultrasonography in the diagnosis of autoimmune pancreatitis and IgG4-related sclerosing cholangitis

Endoscopic retrograde cholangiopancreatography is used to evaluate the narrowing of the main pancreatic duct in autoimmune pancreatitis (AIP) and biliary stricture in IgG4-related sclerosing cholangitis (IgG4-SC). Intraductal ultrasonography enables detailed visualization of the thickening of the bile duct wall in IgG4-SC. Pancreatic cancer, cholangiocarcinoma, and primary sclerosing cholangitis are important mimicking conditions of AIP and IgG4-SC. Diffuse or segmental stricture without marked upstream dilatation is a typical pancreatographic finding in AIP. By contrast, a single, short stricture with marked upstream dilatation is a typical finding in pancreatic cancer. The cholangiogram of IgG4-SC is classified into four types based on biliary stricture location, and this cholangiogram classification is useful for the differential diagnosis of IgG4-SC. Endoscopic retrograde cholangiography can be used to distinguish between IgG4-SC and primary sclerosing cholangitis. A segmental/long and intrapancreatic stricture is a characteristic finding of IgG4-SC, whereas band-like strictures, a beaded or pruned-tree appearance, and diverticulum-like outpouching are characteristic of primary sclerosing cholangitis. The characteristic intraductal ultrasonographic findings of circular-symmetrical wall thickening, smooth outer and inner margins, and homogeneous internal echo at the biliary stricture site are useful for diagnosis of IgG4-SC. Thickening of the bile duct wall at non-stricture sites is also a typical intraductal ultrasonographic finding of IgG4-SC and can be used for differential diagnosis from cholangiocarcinoma. Transpapillary bile duct and duodenal papilla biopsy during endoscopic retrograde cholangiopancreatography are also useful in the diagnosis of IgG4-SC.

[Recent Updates of Immunoglobulin G4-related Pancreatobiliary Disease]

Type 1 autoimmune pancreatitis and IgG4-related sclerosing cholangitis (IgG4-SC) are the pancreatobiliary manifestations of IgG4-related disease. IgG4-related disease is a newly named fibroinflammatory condition that is characterized by tumefactive lesions that contain dense lymphoplasmacytic infiltrates rich in IgG4-positive cells and often by elevated serum IgG4 concentrations. IgG4-related pancreatobiliary disease is often disguised as pancreatobiliary malignancies owing to its tumefactive nature and clinical presentations, such as obstructive jaundice. The differentiation of IgG4-SC from primary sclerosing cholangitis is also essential because of the significant differences in treatment responses and prognosis. A timely diagnosis of IgG4-related pancreatobiliary disease can lead clinicians to prescribe adequate glucocorticoid treatment that can reverse the pancreatobiliary duct strictures and obstructive jaundice. On the other hand, the diagnosis of IgG4-related pancreatobiliary disease is sometimes challenging because there is no single diagnostic clinical test. The diagnosis of IgG4-related pancreatobiliary disease rests on fulfilling the diagnostic criteria, including imaging, serology, other organ involvement, histology, and response to steroids. Approximately 50% of patients with IgG4-related pancreatobiliary disease experience relapse, despite IgG4-related pancreatobiliary disease showings a favorable short-term prognosis after glucocorticoid therapy. To reduce the relapse, long maintenance treatment for 3 years may be necessary. The purposes of this review were to emphasize the clinical problem of diagnosing IgG4-related pancreatobiliary disease as well as to highlight the use of the published guidelines for the diagnosis and management of IgG4-related pancreatobiliary disease.

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.

Liquid biopsy in cholangiocarcinoma: Current status and future perspectives

Cholangiocarcinoma (CCA) are a heterogeneous group of tumors in terms of aetiology, natural history, morphological subtypes, molecular alterations and management, but all sharing complex diagnosis, management, and poor prognosis. Several mutated genes and epigenetic changes have been detected in CCA, with the potential to identify diagnostic and prognostic biomarkers and therapeutic targets. Accessing tumoral components and genetic material is therefore crucial for the diagnosis, management and selection of targeted therapies; but sampling tumor tissue, when possible, is often risky and difficult to be repeated at different time points. Liquid biopsy (LB) represents a way to overcome these issues and comprises a diverse group of methodologies centering around detection of tumor biomarkers from fluid samples. Compared to the traditional tissue sampling methods LB is less invasive and can be serially repeated, allowing a real-time monitoring of the tumor genetic profile or the response to therapy. In this review, we analysis the current evidence on the possible roles of LB (circulating DNA, circulating RNA, exosomes, cytokines) in the diagnosis and management of patients affected by CCA.

Differences in Clinical Features and Diagnostic Strategies Between IgG4-Related Autoimmune Cholangitis and Cholangiocarcinoma

IgG4-related autoimmune cholangitis (IgG4-AIC) is often difficult to distinguish from cholangiocarcinoma (CCA). This study aimed to determine a practical clinical strategy for distinguishing between IgG4-AIC and CCA to avoid unnecessary surgical resection. We retrospectively collected and compared the clinicopathological data between IgG4-AIC and CCA patients, including the clinical, serological, and radiological characteristics, to follow up on these patients to investigate the prognosis. Among the 377 patients who received surgical resection for suspecting CCA at the Sun Yat-Sen Memorial Hospital between June 2004 and June 2014, 14 patients were diagnosed as IgG4-AIC through histochemistry after surgery. Immunohistochemistry revealed that IgG4 was up-regulated in the plasma cells of IgG4-AIC tissues in 13 out of 14 patients. The serum CA19-9 level was significantly lower than in the CCA group. Patients with IgG4-AIC can only see slight or no enhancement under the contrast enhancement CT scan, while there are no signs of ring-like or delayed enhancement that is unique to CCA. Thirteen patients were followed up, and the time was 12 to 92 months. Three of them were regularly treated with prednisone after surgery, and original symptoms disappeared. Our study demonstrated that the combination of imaging with serum CA19-9 could improve the preoperative diagnostic value and reduce the rate of unnecessary resection.

Clinical diagnostic criteria for IgG4-related sclerosing cholangitis 2020: (Revision of the clinical diagnostic criteria for IgG4-related sclerosing cholangitis 2012)

Several years have passed since the clinical diagnostic criteria for IgG4-related sclerosing cholangitis 2012 were published. New findings and knowledge have accumulated since then. The Research Committees for IgG4-related Diseases and for Intractable Diseases of the Liver and Biliary Tract, in association with the Ministry of Health, Labor, and Welfare of Japan and the Japan Biliary Association, have established a working group consisting of researchers specializing in IgG4-SC and have drawn up new clinical diagnostic criteria for IgG4-SC 2020. The diagnosis of IgG4-SC is based on a combination of the following six criteria: (a) narrowing of the intra- or extrahepatic bile duct; (b) thickening of the bile duct wall; (c) serological findings; (d) pathological findings; (e) other organ involvement; and (f) effectiveness of steroid therapy. These new diagnostic criteria for IgG4-SC are useful in practice for general physicians and other non-specialists.

IgG4-Related Sclerosing Cholangitis Mimicking Cholangiocarcinoma

IgG4-related sclerosing cholangitis (IgG4-SC) is a relatively newly identified disease that is frequently associated with autoimmune pancreatitis. The differential diagnosis between cholangiocarcinoma, primary sclerosing cholangitis, and IgG4-SC can be challenging due to significant overlap among the clinical and imaging characteristics. We report the case of a 71-year-old woman who was diagnosed with IgG4-related disease based on increased serum IgG4 levels, imaging, and clinical presentation, which showed systemic involvement, including sclerosing cholangitis and kidneys. The patient presented with chronic jaundice. Magnetic resonance imaging revealed bile duct strictures and the dilatation of upstream bile ducts, smooth wall thickening with uniform enhancement in the delayed phase, and no vascular infiltration. Multiple low-density, wedge-shaped areas were identified in both kidneys, which were hypointense on T2-weighted images and hyperintense on diffusion-weighted images. The serum IgG4 levels of this patient were elevated to nearly 10-fold the normal upper limit. A diagnosis of IgG4-SC associated with IgG4-related kidney was made. Based on this case, pre-surgery IgG4 serum treatment in patients with non-malignant bile duct stenosis was recommended to exclude IgG4-SC.

Cholangiocarcinoma Presenting after Eight Years of Treatment of IgG4-Related Autoimmune Pancreatitis with Steroids

Autoimmune pancreatitis (AIP) is characterized by pancreatic manifestations of IgG4-related disease. Malignancies in patients with AIP have been reported, but carcinoma of the bile duct is extremely rare. We report a patient with IgG4-related AIP who developed cholangiocarcinoma after 8 years of steroid treatment. A 76-year-old male presented with fever (37.8°C) due to biliary obstruction and cholangitis. He had been treated with steroids for 8 years to control inflammation due to IgG4-related AIP. During 8 years of treatment, hepatobiliary enzyme levels were well controlled within their normal range, but serum IgG4 levels remained elevated. A computed tomography scan showed intrahepatic bile duct dilatation. Magnetic resonance cholangiopancreatography showed obstructive changes at the junction of the cystic and common ducts. To relieve biliary obstruction, endoscopic bile duct drainage using a nasobiliary tube was performed, and cytology was Class IV. Aorto-caval lymph node enlargement was found at laparotomy, intraoperatively diagnosed as adenocarcinoma, and resection was abandoned. He died 4 months postoperatively. We report a patient with IgG4-related AIP complicated by cholangiocarcinoma which developed after 8 years of steroid treatment. Even if hepatobiliary markers are well controlled, periodic follow-up with imaging studies may facilitate detection of an early cholangiocarcinoma.

Biliary inflammation scoring for immunoglobulin G4-related sclerosing cholangitis: an endoscopic approach with endoscopic ultrasound

BACKGROUND AND AIMS

The differential diagnosis of immunoglobulin G4-related sclerosing cholangitis (IgG4-SC) and cholangiocarcinoma (CC) remains a clinical challenge. Imaging modalities play critical roles in the diagnosis of IgG4-SC. The present study aimed to evaluate the differential diagnosis of IgG4-SC and CC based on images of endoscopic ultrasound (EUS).

METHODS

The biliary inflammation scoring (BIS) method for EUS was developed based on the comparison between images of IgG4-SC and that of cholangiocarcinoma (CC) and other acute or chronic cholangitis. In the BIS diagnostic phase, the EUS images from 66 IgG4-SC patients and 44 CC patients were blindly evaluated using the BIS methods.

RESULTS

The sensitivity, specificity, and accuracy of the newly established BIS in distinguishing IgG4-SC from CC were 86% [95% confidence interval (CI) 75-93%], 95% (95% CI 83-99%), and 90% (95% CI 83-94%), respectively.

CONCLUSION

EUS should be considered to be added to the workup algorithm in patients with suspected IgG4-SC as a useful diagnostic procedure. BIS is a promising diagnostic method to discriminate IgG4-SC during the ongoing endoscopy.

The clinical significance of preoperative C-reactive protein/albumin ratio in patients with resected extrahepatic bile duct cancer

PURPOSE

The C-reactive protein (CRP)/albumin ratio has been identified as a potential prognostic factor for several malignancies. We, therefore, assessed the prognostic role of the CRP/albumin ratio in resected extrahepatic cholangiocarcinoma (EC).

MATERIALS AND METHODS

A total of 235 patients were retrospectively analyzed between March 2005 and December 2017. The correlations among the preoperative CRP/albumin ratio, clinicopathological factors, and clinical outcomes were investigated.

RESULTS

There were 143 males (60.8%), and the median age at the diagnosis was 70.1 (range 41.0-85.5) years. Patients were diagnosed with perihilar bile duct cancer (n = 61) and distal bile duct cancer (n = 174). The median recurrence-free survival and overall survival were 32.7 and 38.7 months, respectively. The optimal prognostic cut-off point of the CRP/albumin ratio for the survival was 0.18 (× 10³). According to the Kaplan-Meier analysis with a log-rank test, the high CRP/albumin ratio group (≥ 0.18) had a significantly shorter overall survival than the low CRP/albumin ratio group (< 0.18) (29.8 vs. 54.6 months, p = 0.002). A multivariate logistic regression analysis for the overall survival showed that CA19-9 ≥ 37 and a high CRP/albumin ratio were associated with a shorter overall survival.

CONCLUSION

A high CRP/albumin ratio appears to be significantly associated with clinically worse outcomes in patients with resected EC.

Cholestatic liver disease: Practice guidelines from the Saudi Association for the Study of Liver diseases and Transplantation

Cholestatic liver diseases (CLDs) are a group of diseases characterized by jaundice and cholestasis as the main presentation with different complications, which have considerable impact on the liver and can lead to end-stage liver disease, cirrhosis, and liver-related complications. In the last few years, tremendous progress has been made in understanding the pathophysiology, diagnosis, and treatment of patients with these conditions. However, several aspects related to the management of CLDs remain deficient and unclear. Due to the lack of recommendations that can help in the management, treatment of those conditions, the Saudi Association for the Study of Liver diseases and Transplantation (SASLT) has created a task force group to develop guidelines related to CLDs management in order to provide a standard of care for patients in need. These guidelines provide general guidance for health care professionals to optimize medical care for patients with CLDs for both adult and pediatric populations, in association with clinical judgments to be considered on a case-by-case basis. These guidelines describe common CLDs in Saudi Arabia, with recommendations on the best approach for diagnosis and management of different diseases based on the Grading of Recommendation Assessment (GRADE), combined with a level of evidence available in the literature.

IgG4-related disease: Changing epidemiology and new thoughts on a multisystem disease

IgG4-related disease (IgG4-RD) represents an immune-mediated fibroinflammatory condition with peculiar histopathologic changes that can affect various organs. In 2012 its unified nomenclature was published, which allows to abandon other synonymous names. Up to now, only little is known about its epidemiology around the world. However, although it is generally considered a rare condition, the number of patients with IgG4-RD is increasing enormously. Likewise, the annual number of publications on this subject has increased progressively. The spectrum of clinical manifestations in IgG4-RD is highly variable, depending on the severity of the disease as well as the presence of organ(s) involvement. This review gives an overview on changing epidemiology of IgG4-RD focusing the attention on the large cohorts of patients published in the literature.

IgG4-related sclerosing cholangitis suspected of being malignant tumors: A case series

BACKGROUND

IgG4-related sclerosing cholangitis (IgG4-SC) is the biliary manifestation of IgG4-related disease (IRD). IgG4-SC often has the characteristics of localized thickening of the bile duct wall, dilation of the bile duct, and obstructive jaundice, which are similar to those of biliary and pancreatic malignancies and often lead to delayed diagnosis or even misdiagnosis clinically.

AIM

To improve the clinicians' understanding of IgG4-SC and avoid its misdiagnosis by analyzing the clinical characteristics, diagnosis, and treatment of five cases of IgG4-SC.

METHODS

A retrospective analysis was performed on five cases of IgG4-SC suspected of being space-occupying lesions of the porta hepatis, ampulla, and pancreas at admission. Patient information, including age, gender, symptoms, signs, past medical history, and the process of diagnosis and treatment, was collected.

RESULTS

Four cases showed obstructive jaundice and imaging identified one case of high level biliary obstruction and three cases of low level obstruction, which suggested the possibility of malignancy. The obstruction sites were located in the porta hepatis, pancreatic head, or ampulla. One case was found to have a mass at the neck of the pancreas by physical examination. All five patients had bile duct inflammation, swelling of the pancreas, or space-occupying lesions in the imaging examination. Laboratory examinations revealed elevated bilirubin, mainly direct bilirubin, accompanied by liver dysfunction. Serum IgG4 levels were significantly increased and tumor markers were normal or slightly elevated. Four patients were diagnosed with IgG4-SC by multidisciplinary consultation, and one patient was diagnosed by pathological examination after surgery.

CONCLUSION

Multidisciplinary consultation is an important strategy in diagnosing IgG4-SC and avoiding misdiagnosis.

IgG4-related sclerosing cholangitis- A great mimicker

IgG4-related disease (IgG4 RD) is a multisystem disorder characterized by tumefactive (mass forming) lesions, storiform fibrosis, and IgG4-positive plasma cell infiltration. IgG4 sclerosing cholangitis (IgG4 SC) is the biliary manifestation of IgG4 RD, often in association with autoimmune pancreatitis (AIP). Here, we report two patients with IgG4-related cholangitis mimicking primary sclerosing cholangitis.

Usefulness of ultrasonography to assess the response to steroidal therapy for the rare case of type 2b immunoglobulin G4-related sclerosing cholangitis without pancreatitis: A case report

BACKGROUND

A type 2b immunoglobulin G4 (IgG4)-related sclerosing cholangitis (SC) without autoimmune pancreatitis is a rare condition with IgG4-SC. While the variety of the imaging modalities have tested its usefulness in diagnosing the IgG4-SC, however, the usage of ultrasonography for the assessment of the response to steroidal therapy on the changes of bile duct wall thickness have not been reported in the condition. Therefore, the information of our recent case and reported cases have been summarized.

CASE SUMMARY

We report the case of an 82-year-old Japanese man diagnosed with isolated IgG4-related SC based on the increase of serum IgG4, narrowing of the bile duct, its wall thickness, no complication of autoimmune pancreatitis, and IgG4 positive inflammatory cell infiltration to the wall with the fibrotic changes. The cholangiogram revealed type 2b according to the classification. Corticosteroid treatment showed a favorable effect, with the smooth decrease in serum IgG4 and the improvement of the bile duct wall thickness.

CONCLUSION

As isolated type 2b, IgG4-SC is rare, the images, histological findings, and clinical course of our case will be helpful for physicians to diagnose and treat the new cases appropriately.

Isolated IgG4-related sclerosing cholangitis with normal serum IgG4 levels-A case report

The isolated IgG4-SC that absent from AIP is quite rare and difficult to diagnose. We presented a case of isolated IgG4-SC with the normal serum IgG4 which was hard to differentiate with cholangiocarcinoma. Under such circumstances, liver pathology has a pivotal role in the diagnosis.

Immunoglobulin G4-related sclerosing cholangitis mimicking cholangiocarcinoma: a case report and literature review

Immunoglobulin G4 (IgG4)-related disease (IgG4-RD) is a novel clinical disease that is characterized by elevated serum IgG4 concentrations and tumefaction or tissue infiltrated by IgG4+ plasma cells. The clinical manifestations of IgG4-RD depend on the type of tissues affected. IgG4-related sclerosing cholangitis is a type of IgG4-RD. We report a patient who initially visited a local hospital with a 5-month history of jaundice. He was found to have a mass in the upper part of the common bile duct that mimicked cholangiocarcinoma. He underwent surgery in our hospital and was later diagnosed with IgG4-related sclerosing cholangitis. We administered prednisolone 40 mg once a day for treatment. Taking into account the possible side effects of moderate-dose hormone therapy, we also administered teprenone, potassium chloride, and calcium carbonate. The patient did not have any recurrence of symptoms or adverse drug reactions during follow-up.

Epidemiological features of immunoglobulin G4-related sclerosing cholangitis in Japan

BACKGROUND/PURPOSE

Epidemiological data on immunoglobulin G4-related sclerosing cholangitis (IgG4-SC) are scarce.

METHOD

We randomly selected healthcare facilities from a list of all facilities in Japan. The selection rate was determined according to a stratification based on the facility characteristics and scale. We sent questionnaires to the selected facilities enquiring about the number and sex of patients with IgG4-SC in 2018. Among responding facilities, we further inquired about the clinical characteristics of the patients with IgG4-SC.

RESULTS

We selected 1180 departments from health centers across Japan. Of them, 532 (45.1%) responded to the questionnaires. The number of reported patients with IgG4-SC was 1045, and the estimated point prevalence was 2.18 (95% confidence interval, 2.13-2.23) per 100 000 population. In addition, we enrolled 1096 patients with IgG4-SC, combining data from previously and newly registered patients. Male patients comprised 79.5% of the population and patients aged 60-80 years had the highest risk for developing the disease. The follow-up period was 5.1 ± 4.0 years and the 5- and 10-year overall survival rates were 95.3% and 89.0%, respectively.

CONCLUSIONS

The point prevalence of IgG4-SC was 2.18 per 100 000 population. The epidemiological features were similar to those observed in previous studies.

IgG4-related disease in the abdomen and pelvis: atypical findings, pitfalls, and mimics

IgG4-related disease (IgG4-RD) is a systemic, autoimmune, fibroinflammatory disease that can cause multi-organ damage. Although there have been many trials and studies since its recognition in 2003, there is still much that is unknown. Furthermore, IgG4-RD can affect any organ in the body and often has many mimics and alternative diagnoses, which can make for a challenging workup. Imaging plays a substantial role in the diagnosis of IgG4-RD and is often the first occasion where IgG4-RD comes into consideration. Thus, knowledge about the imaging findings of various manifestations of IgG4-RD can aid in the diagnosis and have a significant impact on patient management. In this article, we review the wide array of imaging findings, both typical and atypical, as well as possible mimics of IgG4-RD in the abdomen and pelvis.

European Guideline on IgG4-related digestive disease - UEG and SGF evidence-based recommendations

The overall objective of these guidelines is to provide evidence-based recommendations for the diagnosis and management of immunoglobulin G4 (IgG4)-related digestive disease in adults and children. IgG4-related digestive disease can be diagnosed only with a comprehensive work-up that includes histology, organ morphology at imaging, serology, search for other organ involvement, and response to glucocorticoid treatment. Indications for treatment are symptomatic patients with obstructive jaundice, abdominal pain, posterior pancreatic pain, and involvement of extra-pancreatic digestive organs, including IgG4-related cholangitis. Treatment with glucocorticoids should be weight-based and initiated at a dose of 0.6-0.8 mg/kg body weight/day orally (typical starting dose 30-40 mg/day prednisone equivalent) for 1 month to induce remission and then be tapered within two additional months. Response to initial treatment should be assessed at week 2-4 with clinical, biochemical and morphological markers. Maintenance treatment with glucocorticoids should be considered in multi-organ disease or history of relapse. If there is no change in disease activity and burden within 3 months, the diagnosis should be reconsidered. If the disease relapsed during the 3 months of treatment, immunosuppressive drugs should be added.

Management of biliary stricture in patients with IgG4-related sclerosing cholangitis

Background

We aimed to determine the optimal approach with endoscopic biliary drainage (EBD) and corticosteroid (CS) for the treatment of IgG4-related sclerosing cholangitis (ISC).

Methods

To evaluate the safety of EBD for treatment of biliary stricture caused by ISC, we assessed the risk of stent dislodgement and sought to determine the most appropriate time for stent removal. We also assessed the safety of treatment with CS alone for patients with obstructive jaundice, and the rate of and risk factors for biliary tract complications.

Results

Sixty-nine patients with ISC treated with CS were enrolled. Twenty-eight patients (40.6%) were treated with EBD for biliary stricture before CS initiation. Intentional stent removal was performed in thirteen (46.4%) after confirming CS-induced improvement. Eleven of thirteen patients (84.6%) underwent stent removal within 1 month after CS initiation and all their stent removals were safely carried out without early (within two weeks) recurrence of obstructive jaundice. Ten of twenty-eight patients (35.7%) experienced spontaneous stent dislodgement after CS initiation, and seven (70%) of them developed stent dislodgement two weeks to two months after CS initiation. Among forty-one patients treated with CS alone without EBD, 10 patients had obstructive jaundice at the time of CS initiation and all of them achieved clinical improvement without biliary tract infection. During the follow-up, three patients (4.3%), all of whom had undergone EBD, developed bile-duct stones, while none of those treated with CS alone developed bile-duct stones (p = 0.032). Long-term biliary stenting was a risk factor for bile-duct stones.

Conclusions

Biliary stent removal should be carried out within 2 weeks after CS initiation if biliary stricture improves to prevent stent dislodgement. Obstructive jaundice can be treated safely with CS alone in patients without infection. Clinicians should be aware of the possibility of bile-duct stones in patients treated with EBD.

Nationwide epidemiological survey of autoimmune pancreatitis in Japan in 2016

BACKGROUND

To further clarify the clinico-epidemiological features of autoimmune pancreatitis (AIP) in Japan, we conducted the fourth nationwide epidemiological survey.

METHODS

This study consisted of two stage surveys; the number of AIP patients was estimated by the first survey and their clinical features were assessed by the second survey. We surveyed the AIP patients who had visited hospitals in 2016.

RESULTS

The estimated number of AIP patients in 2016 was 13,436, with an overall prevalence rate of 10.1 per 100,000 persons. The estimated number of newly diagnosed patients was 3984, with an annual incidence rate of 3.1 per 100,000 persons. Compared to the 2011 survey, both numbers more than doubled. We obtained detailed clinical information of 1474 AIP patients. The male-to-female sex ratio was 2.94, the mean age was 68.1, and mean age at diagnosis was 64.8. At diagnosis, 63% patients were symptomatic and nearly half of them presented jaundice. Pancreatic cysts were found in 9% of the patients and calcifications in 6%. Histopathological examination was performed in 64%, mainly by endoscopic ultrasonography-guided fine needle aspiration. Extra-pancreatic lesions were detected in 60% of the patients. Eighty-four % patients received the initial steroid therapy, and 85% received maintenance steroid therapy. Kaplan-Meier analysis revealed that the relapsed survival was 14% at 3 years, 25% at 5 years, 40% at 10 years, and 50% at 15 years. Mortality was favorable, but pancreatic cancer accounted for death in one quarter of fatal cases.

CONCLUSION

We clarified the current status of AIP in Japan.

IgG4-related Sclerosing Cholangitis Mimicking Cholangiocarcinoma Diagnosed by Endoscopic Ultrasound-guided Fine-needle Aspiration

A 58-year-old man was referred for obstructive jaundice. Imaging modalities revealed the presence of multiple pancreatic tumors and the stenosis of the middle common bile duct due to a hypoenhanced localized tumor. The multiple pancreatic tumors were histopathologically diagnosed as autoimmune pancreatitis by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA). To differentiate between IgG4-related sclerosing cholangitis (IgG4-SC) and cholangiocarcinoma, we diagnosed the biliary tumor as IgG4-SC by EUS-FNA because of insufficient pathological materials obtained in a transpapillary manner. We herein report a case of IgG4-SC diagnosed by EUS-FNA.

Pancreatic and biliary tract involvement in IgG4-related disease

The diagnosis and treatment of pancreatic and biliary tract involvement in IgG4 disease can be challenging for physicians. A French series shows that the pancreas is the most frequently involved organ in systemic IgG4 disease. Pancreatitis may be found in more than 50% of patients with IgG4 disease and the biliary tract is involved in one third. Pancreatic or biliary involvement may be isolated, metachronous or synchronous of other IgG4-related organ injuries. Pancreatitis related to IgG4 disease is called autoimmune pancreatitis (AIP) type 1. The diagnosis is mainly suspected in the presence of symptoms and morphological features. Changes observed on conventional imaging are not typical and are usually similar to lesions observed in autoimmune pancreatitis type 2. AIP type 1 can also sometimes have a clinical or morphological presentation that mimics pancreatic cancer, especially pseudo-tumoral forms, associated with obstructive jaundice, weight loss and fatigue. Thus, the first challenge is to confirm the diagnosis of autoimmune pancreatitis and to exclude cancer. The AIP type must then be determined to decide on the most appropriate treatment.

IgG4-Related Sclerosing Cholangitis and Primary Sclerosing Cholangitis

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

Validity and safety of endoscopic biliary stenting for biliary stricture associated with IgG4-related pancreatobiliary disease during steroid therapy

Background  Patients with IgG4-related sclerosing cholangitis and autoimmune pancreatitis frequently develop obstructive jaundice, which requires endoscopic biliary stenting (EBS) during steroid therapy to prevent bile duct infection from cholestasis and adverse steroid effects. However, it is controversial whether EBS during steroid therapy is advisable, because the procedure itself carries a risk of cholangitis and procedure-related adverse events. This study aimed to clarify the validity and safety of EBS for patients with biliary stricture associated with IgG4-related pancreatobiliary disease (IgG4-PBD) during steroid therapy. Methods  We enrolled 59 patients who presented with biliary stricture exhibiting jaundice or liver dysfunction and who were treated with EBS. The incidences of recurrent biliary obstruction and acute cholangitis were compared for EBS cases with and without steroid administration. Results  EBS was present in 55 periods with steroid administration and 110 periods without. The incidence of recurrent biliary obstruction was significantly lower in cases with steroids than in those without (1-month no obstruction rate: 100 % vs. 82 %; log-rank test P  = 0.0015). The incidence of acute cholangitis related to stenting was significantly lower in cases with steroids than in those without (1-month no acute cholangitis rate: 100 % vs. 90 %; log-rank test P  = 0.0278). Biliary stents could be removed without acute cholangitis, liver dysfunction, or stent replacement in 96 % of patients who underwent endoscopic retrograde cholangiopancreatography 1 month after commencing steroid administration. Conclusions  EBS during steroid administration was both valid and safe in patients with biliary stricture associated with IgG4-PBD. Stents could be safely removed 1 month after steroid initiation.