IgG4-related sclerosing cholangitis and chronic sclerosing sialadenitis mimicking cholangiocarcinoma and neck malignancy

To the Editor:IgG4-related sclerosing cholangitis（IgG4-SC）has re cently been recognized as a biliary manifestation of IgG4-related disease（IgG4-RD）.Type 3 IgG4-SC pre sented biliary strictures in both the porta hepatis and the distal common bile duct（CBD）.;Its manifestation especially in the absence of autoimmune pancreatitis,is extremely rare and very similar to that of cholangiocarci noma（CC）.

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

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

A Case of Warthin’s Tumor Together with IgG4-Related Sialadenitis

Warthin’s tumor is the second most frequent neoplasm next to pleomorphic adenoma in the salivary gland. The tumor contains the epithelial oncocyte cells with the presence of rich-mitochondria and their surrounding abundant lymphocytes. A relatively new disease entity of IgG4-related disease frequently occurs in the salivary gland. However, the coexistence of Warthin’s tumor and IgG4-related disease is scarcely observed. We have recently experienced a rare case of Warthin’s tumor with IgG4-related sialadenitis. A 51-year-old man presented to our hospital, complaining of a mass with right submandibular tenderness and spontaneous pain. A computed tomography scan of the cervical region revealed a suspicion of lymph node proliferative disease, including malignant lymphoma. Elevated serum levels of IL-2R: 1843 U/ml (reference value 122 - 496 U/ml), IgG: 3430 mg/dl (reference value 861 - 1747 mg/dl), and IgG4: 3140 mg/dl (reference value 11 - 121 mg/dl) were observed. Other laboratory data showed within normal ranges. The cervical tumor was diagnosed as Warthin’s tumor by the findings of fine-needle aspiration cytology and biopsy examination. Immunohistochemistry revealed numerous IgG4- and IgG-positive cells with fibrosis surrounding the epithelial component of Warthin’s tumor, suggesting IgG4-rerated sialadenitis. Finally, we diagnosed the cervical tumor as Warthin tumor with IgG4-related sialadenitis. This is the second report describing a case of Warthin’s tumor with possible involvement of IgG4-related sialadenitis.

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.

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.

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

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

Interleukin-13 promotes cellular senescence through inducing mitochondrial dysfunction in IgG4-related sialadenitis

Immunoglobulin G4-related sialadenitis(IgG4-RS)is an immune-mediated fibro-inflammatory disease and the pathogenesis is still not fully understood.The aim of this study was to explore the role and mechanism of interleukin-13(IL-13)in the cellular senescence during the progress of IgG4-RS.We found that the expression of IL-13 and IL-13 receptorα1(IL-13Rα1)as well as the number of senescent cells were significantly higher in the submandibular glands(SMGs)of IgG4-RS patients.IL-13 directly induced senescence as shown by the elevated activity of senescence-associatedβ-galactosidase(SA-β-gal),the decreased cell proliferation,and the upregulation of senescence markers(p53 and p16)and senescence-associated secretory phenotype(SASP)factors(IL-1βand IL-6)in SMG-C6 cells.Mechanistically,IL-13 increased the level of phosphorylated signal transducer and activator of transcription 6(p-STAT6)and mitochondrial-reactive oxygen species(mt ROS),while decreased the mitochondrial membrane potential,ATP level,and the expression and activity of superoxide dismutase 2(SOD2).Notably,the IL-13-induced cellular senescence and mitochondrial dysfunction could be inhibited by pretreatment with either STAT6 inhibitor AS1517499 or mitochondria-targeted ROS scavenger Mito TEMPO.Moreover,IL-13 increased the interaction between p-STAT6 and c AMP-response element binding protein(CREB)-binding protein(CBP)and decreased the transcriptional activity of CREB on SOD2.Taken together,our findings revealed a critical role of IL-13 in the induction of salivary gland epithelial cell senescence through the elevated mitochondrial oxidative stress in a STAT6–CREB–SOD2-dependent pathway in IgG4-RS.

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.

Multiple intrahepatic artery aneurysms during the treatment for IgG4-related sclerosing cholangitis:A case report

BACKGROUND The purpose of this case report is to describe a case of multiple intrahepatic artery aneurysms during treatment for IgG4-related sclerosing cholangitis(IgG4-SC)and to provide information for daily practice.CASE SUMMARY A 64-year-old Japanese woman was diagnosed with IgG4-SC five years prior and was receiving maintenance treatment with prednisolone 7.5-10 mg/day.She developed abdominal pain and a sudden onset of black stool and was admitted to our hospital.Abdominal contrast-enhanced computed tomography(CT)and ultra-sonography(US)revealed multiple intrahepatic artery aneurysms that developed during the treatment for IgG4-SC.Emergency transarterial embolization for mu-ltiple hepatic artery aneurysms was performed.Hepatic artery aneurysms disappeared on contrast-enhanced CT and US,the progression of anemia ceased,and the melena resolved.Thus,hemostasis was achieved.CONCLUSION Hepatic artery aneurysms should be considered poor prognostic complications of IgG4-SC.

Multi-organ IgG4-related disease continues to mislead clinicians: A case report and literature review

BACKGROUND Immunoglobulin G4-related disease(IgG4-RD)is a multisystemic mass forming immune-mediated disease that affects almost every organ and is a diagnostic challenge for every clinician.There is a lack of adequate epidemiological data worldwide,and evidence-based treatment recommendations are not yet established.We report the first case of IgG4-RD from Lithuania and the Baltic Sea region presented with thyroiditis,orbital myositis,orbitopathy,uveitis,scleritis,sialadenitis,autoimmune pancreatitis and prostatitis.CASE SUMMARY A 54-year-old Caucasian male was admitted to our tertiary Centre complaining of severe weight loss,diarrhoea,abdominal pain,salivary gland swelling,sicca symptoms and diplopia.On examination,bilateral palpable masses in the projection of major salivary glands,severe protrusion of the left eyeball and cachexia were noted.The patient was previously diagnosed with autoimmune thyroiditis and endocrine ophthalmopathy.The magnetic resonance imaging(MRI)of the head revealed enlarged extraocular muscles indicating orbital myositis.The biopsy from the salivary gland mass indicated sialadenitis.Abdominal MRI showed signs of autoimmune pancreatitis,and a serological test revealed the elevated serum IgG4 concentration.The patient was then diagnosed with IgG4-RD and successfully treated with prednisolone.There was a significant clinical,serological and radiological improvement after one month of treatment and no signs of relapse within twenty months.However,it took almost 18 years and the efforts of eight different medical specialists to establish the correct diagnosis.CONCLUSION A comprehensive approach to the patient is essential to improving the recognition of rare immune system conditions,such as IgG4-RD.

Isolated Multifocal Sclerosing Thyroiditis: Case Report

Multifocal fibrosclerosis is a very rare fibroproliferative syndrome involving multiple organ systems. In our report we present the case of multifocal sclerosing thyroiditis characterized by multiple fibroelastic foci similar to breast “radial scar”, which can be misdiagnosed as multifocal papillary carcinoma. The diagnosis of multifocal sclerosing thyroiditis, in according with Armed Forces Institute of Pathology (AFIP) textbook on thyroid tumors, was made only after histological and himmunohistochemical examination. We consider the multifocal sclerosing thyroiditis as the first stage of multifocal IgG4-related sclerosing disease for the presence of IgG4 within fibrosclerotic tissue of thyroid. Total body CT-scan and plamatic IgG4 levels must be investigated in order to exclude or confirm the presence of systemic disease.

The protean manifestations of central nervous system IgG4-related hypertrophic pachymeningitis:a report of two cases

Background:IgG4-related hypertrophic pachymeningitis is a relative newly recognized and rare manifestation of IgG4-related disease,an immune-mediated fibroinflammatory tumefactive disorder.Fewer than 80 patients have been reported in the literature,and it can mimic common neurosurgical conditions.We describe the clinical presentation of two patients that were initially considered to have a subdural collection,tuberculous meningitis,and a cervical spinal meningioma,but were eventually diagnosed with this disease.Case presentation:Two ethnic Chinese men,86 and 62 years old,experienced a 4-week history of headache.Both patients had a history of autoimmune disease,namely glomerulonephritis and Grave’s disease,respectively.Magnetic resonance brain imaging revealed diffuse dural thickening with the latter patient exhibiting homogeneous and intense gadolinium-contrast enhancement.Since the 86-year-old patient also had progressive bilateral visual loss,giant cell arteritis was suspected and a 2-week course of glucocorticoid therapy was prescribed,but his symptoms failed to improve.The 62-year-old patient also had accompanying low-grade fever and was treated empirically as having tuberculous meningitis although there were no confirmatory microbiological findings.This patient further developed right hemiparesis,and additional imaging revealed a C4/5 intradural-extramedullary contrast-enhancing lesion resembling a meningioma causing cord compression.Both patients underwent neurosurgical intervention with the former undergoing a dural biopsy and the latter having the cervical lesion resected.The final diagnosis was IgG4-related hypertrophic pachymeningitis with the hallmark histological features of lymphoplasmacytic infiltration of IgG4+plasma cells,storiform fibrosis,and obliterative phlebitis.In addition,their serum IgG4 levels were elevated(i.e.,>135 mg/dL).Both patients received at least 6 months of glucocorticoid therapy while the latter also had azathioprine.Their symptoms improved significantly and recurrent lesions were not detected on follow-up imaging.Conclusions:A high index of suspicion for this condition is suggested when a male patient with a history of autoimmune disease and compatible radiological findings,experiences subacute headache that is disproportionate to the degree of dural involvement.Neurosurgeons should consider early meningeal biopsy to establish a definitive histological diagnosis in order for early effective immunosuppressive treatment to be initiated and to avoid unnecessary morbidity.

Indolent lung opacity: Ten years follow-up of pulmonary inflammatory pseudo-tumor

Inflammatory pseudotumor(IPT) has always been considered a diagnostic challenge. Its rarity and resemblance to other more common pathological entities imposes that neither clinical nor radiological characteristics can lead to a definitive diagnosis. The surgical excision of the lesion is the ultimate approach for accurate diagnosis and cure. Moreover the true nature of IPT, its origin as a neoplastic entity or an overreactive inflammatory reaction to an unknown trigger, has been a long debated matter. Surgery remains the treatment of choice. IPT is mostly an indolent disease with minimal morbidity and mortality. Local invasion and metastasis predict a poor prognosis. We hereby present a unique case of pulmonary IPT that was surgically excised, but recurred contralaterally, shortly thereafter. Despite no medical or surgical treatment for ten years, the lesion has remained stable in size, with neither symptoms nor extra-pulmonary manifestations.

Eosinophilic cholangitis is a potentially underdiagnosed etiology in indeterminate biliary stricture

To investigate presence and extent of eosinophilic cholangitis (EC) as well as IgG4-related disease in patients with indeterminate biliary stricture (IBS).METHODSAll patients with diagnosis of sclerosing cholangitis (SC) and histopathological samples such as biopsies or surgical specimens at University Hospital Frankfurt from 2005-2015 were included. Histopathological diagnoses as well as further clinical course were reviewed. Tissue samples of patients without definite diagnosis after complete diagnostic work-up were reviewed regarding presence of eosinophilic infiltration and IgG4 positive plasma cells. Eosinophilic infiltration was as well assessed in a control group of liver transplant donors and patients with primary sclerosing cholangitis.RESULTSone hundred and thirty-five patients with SC were included. In 10/135 (13.5%) patients, no potential cause of IBS could be identified after complete diagnostic work-up and further clinical course. After histopathological review, a post-hoc diagnosis of EC was established in three patients resulting in a prevalence of 2.2% (3/135) of all patients with SC as well as 30% (3/10) of patients, where no cause of IBS was identified. 2/3 patients with post-hoc diagnosis of EC underwent surgical resection with suspicion for malignancy. Diagnosis of IgG4-related cholangitis was observed in 7/135 patients (5.1%), whereas 3 cases were discovered in post-hoc analysis. 6/7 cases with IgG4-related cholangitis (85.7%) presented with eosinophilic infiltration in addition to IgG4 positive plasma cells. There was no patient with eosinophilic infiltration in the control group of liver transplant donors (n = 27) and patients with primary sclerosing cholangitis (n = 14).CONCLUSIONEC is an underdiagnosed benign etiology of SC and IBS, which has to be considered in differential diagnosis of IBS.

Present state of endoscopic ultrasonography-guided fine needle aspiration for the diagnosis of autoimmune pancreatitis type 1

Autoimmune pancreatitis(AIP)is defined as pancreatitis caused by irregular narrowing of the pancreatic duct accompanied by pancreatic swelling,fibrosis and lymphocyte infiltration,events that are related to autoimmune mechanisms.The 2010 International Consensus Diagnostic Criteria for AIP defined pancreatitis as“type 1”when increased levels of serum IgG4 were present and other organs were involved;lymphoplasmacytic sclerosing pancreatitis was the main histological characteristic.Apart from surgery,endoscopic ultrasonographyguided fine needle aspiration(EUS-FNA)is the only method for the histological diagnosis of AIP;however,this method is difficult.The use of larger-diameter FNA needles and trucut biopsy did not improve the diagnostic performance of EUS-FNA,but it has improved gradually.In this review,we look back at past efforts to improve the diagnostic performance of EUS-FNA and reveal the present state of EUS-FNA for the histological diagnosis of AIP type 1.