Clinicopathological differentiation between sclerosing cholangitis with autoimmune pancreatitis and primary sclerosing cholangitis

Background The present study was undertaken to identify the clinicopathological differences between sclerosing cholangitis with autoimmune pancreatitis (SC-AIP) and primary sclerosing cholangitis (PSC). Methods We retrospectively compared the clinical, cholangiographic, and liver biopsy findings between 24 cases of PSC and 24 cases of SC-AIP. Results Patient age at the time of diagnosis was significantly lower in the PSC group than in the SC-AIP group. The peripheral blood eosinophil count was significantly higher in the PSC group than in the SC-AIP group, but the serum IgG4 level was significantly higher in the SC-AIP group. Cholangiography revealed band-like strictures, beaded appearance, and pruned-tree appearance significantly more frequently in PSC, whereas segmental strictures and strictures of the distal third of the common bile duct were significantly more common in SC-AIP. Liver biopsy revealed fibrous obliterative cholangitis only in the PSC specimens. No advanced fibrous change corresponding to Ludwig's stages 3 and 4 was observed in any of the SC-AIP specimens. IgG4-positive plasma cell infiltration of the liver was significantly more severe in SC-AIP than in PSC. Subsequent cholangiography showed no improvement in any of the PSC cases, but all SC-AIP patients responded to steroid therapy, and improvement in the strictures was observed cholangiographically. Conclusions Based on the differences between the patients' ages and blood chemistry, cholangiographic, and liver biopsy findings, SC-AIP should be differentiated from PSC.     

Diagnostic procedures for IgG4-related sclerosing cholangitis

Background/purpose

IgG4-related sclerosing cholangitis (IgG4-SC) is one of several diseases associated with autoimmune pancreatitis (AIP). However, diffuse cholangraphic abnormalities seen in association with AIP may resemble those seen in primary sclerosing cholangitis (PSC), and the presence of segmental stenosis suggests cholangiocarcinoma. IgG4-SC responds well to steroid therapy, whereas in contrast, liver transplantation is the only effective therapy for PSC, and surgical intervention is also needed for cholangiocarcinoma. The aim of this review was to establish the diagnostic procedures for IgG4-SC.

Methods

A literature search was conducted, covering English-language articles dealing with IgG4-SC published between 1991 and March 2010. As clinical data on IgG4-SC are limited, the author also took into consideration his own clinical experience with the treatment of IgG4-SC over a period of more than 19 years.

Results

When intrapancreatic stenosis is detected, pancreatic cancer should be ruled out. If multiple intrahepatic stenosis is evident, PSC should be discriminated on the basis of cholangiographic findings and liver biopsy with IgG4 immunostaining. An association with inflammatory bowel disease (IBD) is suggestive of PSC. If stenosis is demonstrated in the hepatic hilar region, cholangiocarcinoma should be discriminated by US, EUS, IDUS, and bile duct biopsy.

Conclusion

For diagnosis of IgG4-SC, coexistence of AIP is the most useful finding. However, the most important consideration for clinicians is to be aware of IgG4-SC when encountering patients with obstructive jaundice.     

Diagnosis of IgG4-related sclerosing cholangitis

IgG4-related sclerosing cholangitis(IgG4-SC)is often associated with autoimmune pancreatitis.However,the diffuse cholangiographic abnormalities observed in IgG4-SC may resemble those observed in primary sclerosing cholangitis(PSC),and the presence of segmental stenosis suggests cholangiocarcinoma(CC).IgG4-SC responds well to steroid therapy,whereas PSC is only effectively treated with liver transplantation and CC requires surgical intervention.Since IgG4-SC was first described,it has become a third distinct clinical entity of sclerosing cholangitis.The aim of this review was to introduce the diagnostic methods for IgG4-SC.IgG4-SC should be carefully diagnosed based on a combination of characteristic clinical,serological,morphological,and histopathological features after cholangiographic classification and targeting of a disease for differential diagnosis.When intrapancreatic stenosis is detected,pancreatic cancer or CC should be ruled out.If multiple intrahepatic stenoses are evident,PSC should be distinguished on the basis of cholangiographic findings and liver biopsy with IgG4 immunostaining.Associated inflammatory bowel disease is suggestive of PSC.If stenosis is demonstrated in the hepatic hilar region,CC should be discriminated by ultrasonography,intraductal ultrasonography,bile duct biopsy,and a higher cutoff serum IgG4 level of 182 mg/dL.     

Autoimmune pancreatitis: proposal of IgG4-related sclerosing disease

Autoimmune pancreatitis (AIP) is a peculiar type of pancreatitis of presumed autoimmune etiology. Many new clinical aspects of AIP have been clarified during the past 10 years, and AIP has become a distinct entity recognized worldwide. However, its precise pathogenesis or pathophysiology remains unclear. As AIP dramatically responds to steroid therapy, accurate diagnosis of AIP is necessary to avoid unnecessary surgery. Characteristic dense lymphoplasmacytic infiltration and fibrosis in the pancreas may prove to be the gold standard for diagnosis of AIP. However, since it is difficult to obtain sufficient pancreatic tissue, AIP should be diagnosed currently based on the characteristic radiological findings (irregular narrowing of the main pancreatic duct and enlargement of the pancreas) in combination with serological findings (elevation of serum γ-globulin, IgG, or IgG4, along with the presence of autoantibodies), clinical findings (elderly male preponderance, fluctuating obstructive jaundice without pain, occasional extrapancreatic lesions, and favorable response to steroid therapy), and histopathological findings (dense infiltration of IgG4-positive plasma cells and T lymphocytes with fibrosis and obliterative phlebitis in various organs). It is apparent that elevation of serum IgG4 levels and infiltration of abundant IgG4-positive plasma cells into various organs are rather specific to AIP patients. We propose a new clinicopathological entity, “IgG4-related sclerosing disease”, and suggest that AIP is a pancreatic lesion reflecting this systemic disease.     

Pathology and immunopathology of immunoglobulin G4-related sclerosing cholangitis: The latest addition to the sclerosing cholangitis family

Sclerosing cholangitis is heterogeneous in its etiopathogenesis. Recently, sclerosing cholangitis showing abundant immunoglobulin (Ig)G4+ plasma cell infiltration was added to the sclerosing cholangitis group. This form was frequently associated with sclerosing pancreatitis (autoimmune pancreatitis) and also occasionally with other diseases such as chronic sclerosing sialadenitis, all of which falls within IgG4-related sclerosing disease. Herein, this new member, called IgG4-related sclerosing cholangitis (IgG4-SC), is reviewed. IgG4-SC shows grossly medullary and fleshy lesions along the biliary tree, and histologically marked lymphoplasmacytic infiltration with extensive fibrosis, and obliterative phlebitis, sharing histopathological features with sclerosing pancreatitis. Peribiliary glands are also severely affected. Interestingly, hepatic inflammatory pseudotumor (HIP) is not infrequently associated with IgG4-SC, and is thought as a local exaggeration of IgG4-SC. Immunohistochemically, many IgG4+ plasma cells and CD4+/CD25+ regulatory T cells are found around the affected bile ducts and portal tracts. Incontrast, these cells are scarce in the affected bile ducts of primary sclerosing cholangitis (PSC), a prototype of sclerosing cholangitis. Biliary lining epithelia are relatively spared in IgG4-SC in comparison with those of PSC showing degeneration and ulceration. In some cases of IgG4-SC, IgG4+ plasma cells are also found considerably in small portal tracts, so needle liver biopsy is useful for the diagnosis of IgG4-SC. Therapeutically, IgG4-SC responds well to steroid therapy, while such character is not reported in PSC. Taken together, IgG4-SC may be etiologically different from PSC, and immunopathological processes relating to IgG4 and regulatory T cells may be involved in the pathogenesis of IgG4-SC. Further studies are needed to clarify the etiopathogenesis of IgG4-SC and its related disorders.     

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

To our knowledge, patients with immunoglobulin G4-related sclerosing cholangitis (IgG4-SC) associated with autoimmune hemolytic anemia (AIHA) have not been reported previously. Many patients with IgG4-SC have autoimmune pancreatitis (AIP) and respond to steroid treatment. However, isolated cases of IgG4-SC are difficult to diagnose. We describe our experience with a patient who had IgG4-SC without AIP in whom the presence of AIHA led to diagnosis. The patient was a 73-year-old man who was being treated for dementia. Liver dysfunction was diagnosed on blood tests at another hospital. Imaging studies suggested the presence of carcinoma of the hepatic hilus and primary sclerosing cholangitis, but a rapidly progressing anemia developed simultaneously. After the diagnosis of AIHA, steroid treatment was begun, and the biliary stricture improved. IgG4-SC without AIP was thus diagnosed.     

Sclerosing cholangitis associated with autoimmune pancreatitis differs from primary sclerosing cholangitis

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

Sclerosing cholangitis associated with autoimmune pancreatitis

Autoimmune pancreatitis is a unique form of chronic pancreatitis characterized by irregular narrowing of the pancreatic duct, pancreatic swelling, and a favorable response to corticosteroids, in which the autoimmune mechanism is postulated in the pathogenesis. High serum immunoglobulin (Ig)G4 concentrations and various types of extrapancreatic involvement are prominent features of this disease. Sclerosing cholangitis is a major extrapancreatic lesion of autoimmune pancreatitis that has been regarded as primary sclerosing cholangitis (PSC) complicating chronic pancreatitis. Because sclerosing cholangitis associated with autoimmune pancreatitis (SC-AIP) also favorably responds to corticosteroid therapy, it should be differentiated from PSC. Useful points regarding the differentiation between SC-AIP and PSC are as follows: (i) PSC occurs in younger and SC-AIP in older individuals; (ii) obstructive jaundice is more frequently seen in SC-AIP; (iii) PSC is complicated with inflammatory bowel disease, whereas SC-AIP is complicated with so called extrapancreatic lesions of AIP; (iv) high serum IgG4 concentrations are frequently seen in SC-AIP; (v) a cholangiogram may differentiate the two conditions to some extent; (vi) abundant IgG4-bearing plasma cell infiltration is seen in SC-AIP; and (vii) steroid therapy is effective for SC-AIP. IgG4-related sclerosing cholangitis without pancreatic lesion may be a metachronous phenotype of SC-AIP, and also should be differentiated from PSC. The pathogenesis of AIP and SC-AIP remains unclear. The complement activation system of the classical pathway may be contributing in some cases.     

IgG4-related sclerosing disease

Based on histological and immunohistochemical exami- nation of various organs of patients with autoimmune pancreatitis （AIP）, a novel clinicopathological entity of IgG4-related sclerosing disease has been proposed. This is a systemic disease that is characterized by extensive IgG4-positive plasma cells and T-lymphocyte infiltration of various organs. Clinical manifestations are apparent in the pancreas, bile duct, gallbladder, salivary gland, retroperitoneum, kidney, lung, and prosrate, in which tissue fibrosis with obliterative phlebitis is pathologically induced. AlP is not simply pancreatitis but, in fact, is a pancreatic disease indicative of IgG4- related sclerosing diseases. This disease includes AlP, sclerosing cholangitis, cholecystitis, sialadenitis, retro-peritoneal fibrosis, tubulointerstitial nephritis, interstitial pneumonia, prostatitis, inflammatory pseudotumor and lymphadenopathy, all IgG4-related. Most IgG4-related sclerosing diseases have been found to be associated with AlP, but also those without pancreatic involvement have been reported. In some cases, only one or two organs are clinically involved, while in others, three or four organs are affected. The disease occurs predominantly in older men and responds well to steroid therapy. Serum IgG4 levels and immunos-taining with anti-IgG4 antibody are useful in making the diagnosis. Since malignant tumors are frequently suspected on initial presentation, IgG4-related sclerosing disease should be considered in the differential diagnosis to avoid unnecessary surgery.     

Review of primary sclerosing cholangitis with increased IgG4 levels

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

Isolated intrapancreatic Ig G4-related sclerosing cholangitis

Immunoglobulin G4-related sclerosing cholangitis(Ig G4-SC) is frequently associated with type 1 autoimmune pancreatitis(AIP). Association with AIP can be utilized in the diagnosis of Ig G4-SC. However, some cases of Ig G4-SC are isolated from AIP, which complicates the diagnosis. Most of the reported cases of isolated Ig G4-SC displayed hilar biliary strictures, whereas isolated Ig G4-SC with intrapancreatic biliary stricture is very rare. Recently, we have encountered 5 isolated intrapancreatic Ig G4-SC cases that were not associated with AIP, three of which were pathologically investigated after surgical operation. They all were males with a mean age of 74.2 years. The pancreas was not enlarged in any of these cases. No irregular narrowing of the main pancreatic duct was found. Bile duct wall thickening in lesions without luminal stenosis was detected by abdominal computed tomography in all five cases, by endoscopic ultrasonography in two out of four cases and by intraductal ultrasonography in all three cases. In three cases, serum Ig G4 levels were within the normal limits. The mean serum Ig G4 level measured before surgery was 202.1 mg/d L(4 cases). Isolated intrapancreatic Ig G4-SC is difficult to diagnose, especially if the Ig G4 level remains normal. Thus, this type of Ig G4-SC should be suspected in addition to cholangiocarcinoma and pancreatic cancer if stenosis of intrapancreatic bile duct is present.     

Role of endoscopy in the diagnosis of autoimmune pancreatitis and immunoglobulin G4‐related sclerosing cholangitis

Autoimmune pancreatitis (AIP) must be differentiated from pancreatic carcinoma, and immunoglobulin (Ig)G4‐related sclerosing cholangitis (SC) from cholangiocarcinoma and primary sclerosing cholangitis (PSC). Pancreatographic findings such as a long narrowing of the main pancreatic duct, lack of upstream dilatation, skipped narrowed lesions, and side branches arising from the narrowed portion suggest AIP rather than pancreatic carcinoma. Cholangiographic findings for PSC, including band‐like stricture, beaded or pruned‐tree appearance, or diverticulum‐like outpouching are rarely observed in IgG4‐SC patients, whereas dilatation after a long stricture of the bile duct is common in IgG4‐SC. Transpapillary biopsy for bile duct stricture is useful to rule out cholangiocarcinoma and to support the diagnosis of IgG4‐SC with IgG4‐immunostaining. IgG4‐immunostaining of biopsy specimens from the major papilla advances a diagnosis of AIP. Contrast‐enhanced endoscopic ultrasonography (EUS) and EUS elastography have the potential to predict the histological nature of the lesions. Intraductal ultrasonographic finding of wall thickening in the non‐stenotic bile duct on cholangiography is useful for distinguishing IgG4‐SC from cholangiocarcinoma. Endoscopic ultrasound‐guided fine‐needle aspiration (EUS‐FNA) is widely used to exclude pancreatic carcinoma. To obtain adequate tissue samples for the histological diagnosis of AIP, EUS‐Tru‐cut biopsy or EUS‐FNA using a 19‐gauge needle is recommended, but EUS‐FNA with a 22‐gauge needle can also provide sufficient histological samples with careful sample processing after collection and rapid motion of the FNA needles within the pancreas. Validation of endoscopic imaging criteria and new techniques or devices to increase the diagnostic yield of endoscopic tissue sampling should be developed.     

IgG4相关性硬化性胆管炎100例临床特征分析

目的 由于临床和影像学表现的相似及临床医生认知不足,IgG4相关性硬化性胆管炎(IgG4-SC)常被误诊为原发性硬化性胆管炎(PSC)或胆管癌(CC)等胆汁淤积性疾病,而采取了不必要的手术治疗,因此对IgG4-SC的准确认识非常重要。目前,对IgG4-SC的临床研究比较缺乏,文献多为零星的临床病例报道,缺乏系统总结。我们通过汇总分析国内报道的病例,探讨了IgG4-SC患者的临床特点和误诊原因,以提高对该病的认识和诊断水平。方法 以“IgG4相关性硬化性胆管炎”为关键词在中国知网数据库、万方数据库和维普数据库检索2019年9月前公开发表的文献,并提取相关病例的一般资料、临床表现、实验室检查、影像学表现、病理学特征、误诊情况、治疗和预后等信息进行汇总分析。结果 纳入25篇文献,包括100例患者,男女比例为4∶1,平均发病年龄为(58.8±12.3)岁;最常见的临床表现为黄疸(85%)和腹痛(53%); 94.2%(81/86)患者血清IgG4水平增高,33%患者血清CA19-9升高;影像学表现为胆总管下段狭窄57例,肝门区胆管狭窄伴肝内胆管扩张15例;34例肝组织检查发现胆囊壁/胆管壁纤维组织增生伴大量淋巴细胞和浆细胞浸润,可见闭塞性静脉炎或席纹状硬化;免疫组化检测,15例显示IgG4⁺浆细胞>10/HPF;在100例中,12例因误诊为胆管癌而实施手术治疗,61例应用糖皮质激素治疗,58例(95%)病情缓解。结论 IgG4-SC患者多以梗阻性黄疸和腹痛为主要表现,在临床和影像学表现上与原发性硬化性胆管炎和胆管癌十分相似,需注意鉴别诊断。     

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

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