Autoimmune pancreatitis: clinical and radiological features and objective response to steroid therapy in a UK series

Comorbidity of patients with noncommunicable diseases in general practice. Eurasian guidelines

Создание руководства поддержано Советом по терапевтическим наукам отделения клинической медицины Российской академии наук.

B-Cell depletion therapy in IgG4-related disease: State of the art and future perspectives

IgG4-related disease (IgG4-RD) is an increasingly recognized immune-mediated fibroinflammatory disorder that promptly responds to glucocorticoids but commonly relapses during steroid tapering or after discontinuation. In the last few years, B-cell depletion therapy with rituximab (RTX) proved to be effective in the induction of remission and maintenance treatment of IgG4-RD, providing a new powerful tool in the management of this emerging condition. In this review, we outline the pathogenetic rationale for using B-cell depleting agents in IgG4-RD, we summarize available clinical experience with RTX in this disease, and we describe future possible therapies targeting B-lymphocytes that are now in the pipeline.

Exocrine and Endocrine Insufficiency in Autoimmune Pancreatitis: A Matter of Treatment or Time?

Background: Autoimmune pancreatitis (AIP) is a specific form of chronic pancreatitis with a high relapse rate after treatment. AIP patients are burdened with an increased risk of long-term sequelae such as exocrine and endocrine insufficiency. Our objective was to investigate if pharmacological treatment affects both endocrine and exocrine pancreatic function in patients with AIP. Methods: We included 59 patients with definite AIP in the final analysis. Screening for diabetes mellitus (DM) and pancreatic exocrine insufficiency (PEI) was performed at the time of AIP diagnosis and during follow-up. Results: There were 40 (67.8%) males and 19 (32.2%) females; median age at diagnosis was 65 years. Median follow-up after the diagnosis of AIP was 62 months. PEI prevalence at diagnosis was 72.7% and was 63.5% at follow-up. The cumulative incidence of DM was 17.9%, with a prevalence of DM at diagnosis of 32.8%. No strong association was found between pharmacological treatment and occurrence of PEI and DM. Univariate analysis identified potential risk factors for PEI (other organ involvement and biliary stenting) and for DM (overweight, blue-collar profession, smoking, weight loss or obstructive jaundice as presenting symptoms, imaging showing diffuse pancreatic enlargement, smoking). In a multivariate analysis, only obstructive jaundice was identified as a risk factor for DM both at diagnosis and during follow-up. Conclusions: Our results suggest that the prevalence of endocrine and exocrine insufficiency in AIP is high at diagnosis with an additional risk of PEI and DM during follow-up despite pharmacological treatment.

Incidence of endocrine and exocrine insufficiency in patients with autoimmune pancreatitis at diagnosis and after treatment: a systematic review and meta-analysis

BACKGROUND

Autoimmune pancreatitis (AIP) is a rare form of pancreatitis that may lead to endocrine and exocrine insufficiency if left untreated. AIP clinically responds to glucocorticoids (GCs) therapy, but multiple GCs courses are often required to maintain remission with detrimental effects on glycaemic control.

OBJECTIVE

In this systematic review and meta-analysis, we aimed to assess the rate of endocrine and of exocrine insufficiency at diagnosis and at follow up in patients with AIP as well as the impact of GC therapy on pancreatic function in the long-term.

METHODS

The MEDLINE, SCOPUS, and EMBASE databases were searched from inception to August 2021 to identify studies reporting data on endocrine and exocrine insufficiency in patients with AIP. Pooled events were calculated using a random-effect model and expressed in terms of pooled prevalence rates.

RESULTS

A total of 6522 AIP patients and sixty-two studies were included in the analysis. The pooled estimate rate for the overall prevalence of diabetes in AIP at baseline was 37% (95% CI 32-42, I² 96%). The pooled prevalence rate of exocrine insufficiency was 45% (95%CI 32.9-57.4; I² 97%). The pooled estimate rate of diabetes at follow-up was 44% (95%CI 26.1-62.4) in studies where GCs were given to 100% of patients and 42% (95%CI 30.6-52.9) in studies where GCs were given to less than 100% of patients.

CONCLUSION

A large proportion of patients with AIP displays concomitant exocrine and endocrine insufficiency at the time of diagnosis. The incidence of diabetes at the longest available follow up tends to increase in patients treated with GCs.

The clinical efficacy of azathioprine as maintenance treatment for autoimmune pancreatitis: a systematic review and meta-analysis

The effectiveness of azathioprine (AZA) in preventing relapse and maintaining autoimmune pancreatitis (AIP) remission has been reported; however, most of these studies are case series with no randomized control trials available in the literature. Therefore, this study performed a systematic review and meta-analysis of the existing literature on this subject to determine the clinical efficacy of AZA as maintenance therapy for AIP patients. A systematic search was performed to identify studies on the clinical efficacy of AZA as maintenance therapy in AIP patients. The crude multiple relapse rate was estimated to assess the ability of AZA to control relapses in AIP. Pooled estimates were obtained using a random-effects model with the DerSimonian-Laird method. We identified AIP patients who did not respond to initial steroid treatment, experienced steroid weaning failure, or those who relapsed during remission as refractory cases. After reviewing the studies, ten articles fulfilled the inclusion criteria and were selected for meta-analysis. Of all 4504 patients, 3534 patients were treated with steroids, and 346 patients were treated with AZA for relapsed AIP. In this meta-analysis, 14/73 (19.2%) patients receiving AZA for refractory AIP relapsed. Meanwhile, 14/47 (29.8%) patients without AZA experienced relapse. The integrated odds ratio for relapse risk in patients receiving AZA was estimated to be 0.52 (p = 0.15). This systematic review and meta-analysis demonstrated the efficacy of AZA in preventing relapse of AIP, which supports the use of AZA as a maintenance treatment in patients with AIP who relapse upon withdrawal of steroid therapy.

Experience from the first UK inter-regional specialist multidisciplinary meeting in the diagnosis and management of IgG4-related disease

Immunoglobulin G4-related disease (IgG4-RD) is a complex multisystem fibro-inflammatory disorder, requiring diagnostic differentiation from malignancy and other immune-mediated conditions, and careful management to minimise glucocorticoid-induced toxicity and prevent progressive organ dysfunction. We describe the experience of the first inter-regional specialist IgG4-RD multidisciplinary team meeting (MDM) incorporating a broad range of generalists and specialists, held 6-weekly via web-link between Oxford University Hospitals NHS Foundation Trust and University College London Hospitals NHS Foundation Trust. Over 3 years, there were 206 discussions on 156 patients. Of these, 97 (62%) were considered to have definite or possible IgG4-RD; 67% had multi-organ involvement and 23% had a normal serum IgG4. The average number of specialist opinions sought prior to MDM was four per patient. Management was changed in the majority of patients (74%) with the treatment escalation recommended in 61 cases, including 19 for rituximab. Challenges arose from delays and misdiagnosis, cross-specialty presentation and the management of sub-clinical disease. Our cross-discipline IgG4-RD MDM enabled important diagnostic and management decisions in this complex multisystem disorder, and can be used as a model for other centres in the UK.

Case Report: Development of Type 1 Autoimmune Pancreatitis in an Adolescent With Ulcerative Colitis Mimicking Pancreatic Cancer

Introduction: Autoimmune pancreatitis (AIP) is a rare extraintestinal manifestation of inflammatory bowel disease (IBD) which is typically responsive to corticosteroid treatment. Case Presentation: We report a case of a 17-year-old male diagnosed with ulcerative colitis who subsequently developed acute pancreatitis. Blood tests demonstrated elevated pancreatic enzyme levels of amylase (1319 U/L) and lipase (809 U/L). Abdominal computed tomography revealed peripancreatic fat stranding and the presence of a perisplenic pseudocyst. Azathioprine and mesalazine were stopped as possible causes of drug-induced pancreatitis. However, pancreatic enzymes remained elevated and corticosteroid treatment was started. Despite corticosteroid therapy, amylase and lipase levels continued to increase. Infliximab was started due to a flare in gastrointestinal symptoms of ulcerative colitis. Follow-up abdominal ultrasonography revealed a pancreatic tail mass. Tumor markers, including CA 19-9, were elevated and atypical cells were seen on histological examination of an endoscopic ultrasonography-guided fine needle aspiration biopsy. Surgical pancreaticosplenectomy was performed for suspected pancreatic neoplasm. Surprisingly, histology revealed chronic pancreatitis with storiform fibrosis and infiltration of IgG4-positive cells, compatible with AIP type 1. Thereafter, pancreatic enzymes gradually decreased to normal levels and the patient has been in remission for 9 months on infliximab monotherapy. Conclusion: Pediatric gastroenterologists should keep in mind that AIP may develop during the natural course of pediatric IBD. Moreover, the development of pancreatic fibrosis may be non-responsive to corticosteroid treatment and mimic pancreatic neoplasia.

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.

Multicentric Italian survey on daily practice for autoimmune pancreatitis: Clinical data, diagnosis, treatment, and evolution toward pancreatic insufficiency

BACKGROUND

Autoimmune pancreatitis (AIP) is a rare, and relatively new, form of chronic pancreatitis. The management of AIP can vary considerably among different centres in daily clinical practice.

OBJECTIVES

The aim of this study is to present a picture of epidemiological, clinical characteristics, outcomes, and the real-life practice in terms of management in several academic and non-academic centres in Italy.

METHODS

Data on the clinical presentation, diagnostic work-up, treatments, frequency of relapses, and long-term outcomes were retrospectively collected in a cohort of AIP patients diagnosed at 14 centres in Italy.

RESULTS

One hundred and six patients were classified as type 1 AIP, 48 as type 2 AIP, and 19 as not otherwise specified. Epidemiological, clinical, radiological, and serological characteristics, and relapses were similar to those previously reported for different types of AIP. Endoscopic cytohistology was available in 46.2% of cases, and diagnostic for AIP in only 35.2%. Steroid trial to aid diagnosis was administered in 43.3% cases, and effective in 93.3%. Steroid therapy was used in 70.5% of cases, and effective in 92.6% of patients. Maintenance therapy with low dose of steroid (MST) was prescribed in 25.4% of cases at a mean dose of 5 (±1.4) mg/die, and median time of MST was 60 days. Immunosuppressive drugs were rarely used (10.9%), and rituximab in 1.7%. Faecal elastase-1 was evaluated in only 31.2% of patients, and was pathological in 59.2%.

CONCLUSIONS

In this cohort of AIP patients, diagnosis and classification for subtype was frequently possible, confirming the different characteristics of AIP1 and AIP2 previously reported. Nevertheless, we observed a low use of histology and steroid trial for a diagnosis of AIP. Steroid treatment was the most used therapy in our cohort. Immunosuppressants and rituximab were rarely used. The evaluation of exocrine pancreatic insufficiency is underemployed considering its high prevalence.

Differentiation of focal autoimmune pancreatitis from pancreatic ductal adenocarcinoma

Autoimmune pancreatitis (AIP) is an inflammatory process of the pancreas that occurs most commonly in elderly males and clinically can mimic pancreatic adenocarcinoma and present with jaundice, weight loss, and abdominal pain. Mass-forming lesions in the pancreas are seen in the focal form of AIP and both clinical and imaging findings can overlap those of pancreatic cancer. The accurate distinction of AIP from pancreatic cancer is of utmost importance as it means avoiding unnecessary surgery in AIP cases or inaccurate steroid treatment in patients with pancreatic cancer. Imaging concomitantly with serological examinations (IgG4 and Ca 19-9) plays an important role in the distinction between these entities. Characteristic extra-pancreatic manifestations as well as favorable good response to treatment with steroids are characteristic of AIP. This paper will review current diagnostic parameters useful in differentiating between focal AIP and pancreatic adenocarcinoma.

Cardiovascular and Lung Involvement in Patients with Autoimmune Pancreatitis

Introduction: Immunoglobulin G4-related disease (IgG4-RD) is a systemic immune-mediated disease characterised pathologically by the infiltration of IgG4-bearing plasma cells into the involved organs. Autoimmune pancreatitis (AIP) is a form of chronic pancreatitis with a heavy lymphocytic infiltration and two distinct histopathological subtypes, namely: lymphoplasmacytic sclerosing pancreatitis (AIP type 1) and idiopathic duct-centric pancreatitis (AIP type 2). Lung involvement and aortic involvement have been reported in 12% and 9% of patients with systemic IgG4-RD, respectively. In series including patients with AIP, both lung and aortic involvement were described in 2% of the patients. Most of the epidemiological data come from Japan, and there is a lack of information from Europe, especially the Scandinavian countries. Patients and methods: We performed a single-centre retrospective study on a prospectively collected cohort of patients diagnosed with AIP at the Department for Digestive Diseases at Karolinska University Hospital in Stockholm, Sweden, from 2004 to 2019. Demographic and clinical data were collected from the medical charts. Results: One hundred and thirty-three patients with AIP were analysed. Six patients were excluded because they lacked some of the clinical data relevant to the study. Demographic and clinical features of 127 patients were presented. There were 98 patients with AIP type 1-35 (35.7%) female and 63 (64.3%) male, with a mean age of 55.4 ± 18.2. Among them, 15 (15.3%) patients had lung and/or cardiovascular involvement-11 (11.2%) patients had lung involvement, 10 (10.2%) patients had cardiovascular involvement (six patients had both). Most of them (67.0%) had never smoked. The mean follow-up time of the patients with AIP type 1 was 49 months. Conclusions: Lung and/or cardiovascular involvement were diagnosed in 15 (15.3%) patients in our historical cohort of patients with AIP type 1. Most of the lung involvement was presented in the form of nodular lesions in the lungs, non-specific infiltrates, “ground-glass” appearance with pleura thickening, and effusion. Aortic involvement was a major form of vascular involvement in patients with AIP, as in previous published studies on patients with IgG4-RD.

Pitfalls in the MDCT of pancreatic cancer: strategies for minimizing errors

Multidetector computed tomography (MDCT) is a widely used cross-sectional imaging modality for initial evaluation of patients with suspected pancreatic ductal adenocarcinoma (PDAC). However, diagnosis of PDAC can be challenging due to numerous pitfalls associated with image acquisition and interpretation, including technical factors, imaging features, and cognitive errors. Accurate diagnosis requires familiarity with these pitfalls, as these can be minimized using systematic strategies. Suboptimal acquisition protocols and other technical errors such as motion artifacts and incomplete anatomical coverage increase the risk of misdiagnosis. Interpretation of images can be challenging due to intrinsic tumor features (including small and isoenhancing masses, exophytic masses, subtle pancreatic duct irregularities, and diffuse tumor infiltration), presence of coexisting pathology (including chronic pancreatitis and intraductal papillary mucinous neoplasm), mimickers of PDAC (including focal fatty infiltration and focal pancreatitis), distracting findings, and satisfaction of search. Awareness of pitfalls associated with the diagnosis of PDAC along with the strategies to avoid them will help radiologists to minimize technical and interpretation errors. Cognizance and mitigation of these errors can lead to earlier PDAC diagnosis and ultimately improve patient prognosis.

Diagnosis and management of IgG4-related disease

IgG subclass 4-related disease (IgG4-RD) is a rare but increasingly recognised fibroinflammatory condition known to affect multiple organs. IgG4-RD is characterised by unique histological features of lymphoplasmacytic infiltration, storiform fibrosis and obliterative phlebitis. In this review we describe the pancreaticobiliary manifestations of IgG4-RD, with particular emphasis on type 1 autoimmune pancreatitis (AIP) and IgG4-related sclerosing cholangitis (IgG4-SC). AIP and IgG4-SC can pose diagnostic challenges to the clinician as they may mimic pancreatic cancer and primary sclerosing cholangitis, respectively. We discuss current knowledge, clinical diagnostic criteria and recent advances and summarise the evidence base for current therapeutic approaches for AIP and IgG4-SC.

Kidney Involvement in Patients with Type 1 Autoimmune Pancreatitis

Introduction: Autoimmune pancreatitis (AIP) type 1 is a special form of chronic pancreatitis with a strong lymphocytic infiltration as the pathological hallmark and other organ involvement (OOI). IgG4-related kidney disease (IgG4-RKD) was first reported as an extrapancreatic manifestation of AIP in 2004. The aim of the present study was to determine the frequency and clinical impact of kidney lesions observed in patients with AIP type 1. Methods: We performed a single-centre retrospective study on a prospectively collected cohort of patients with a histologically proven or highly probable diagnosis of AIP according to the International Consensus Diagnostic Criteria (ICDC) classification. Results: Seventy-one patients with AIP were evaluated. AIP type 1 was diagnosed in 62 (87%) patients. Kidney involvement was present in 17 (27.4%) patients with AIP type 1: 15 (88.2%) males and 2 (11.8%) females. Laboratory and/or imaging signs of kidney involvement were presented at the time of AIP diagnosis in eight (47.1%) patients. In other patients, the onset of kidney involvement occurred between four months and eight years following diagnosis. At the time of the diagnosis of kidney involvement, eight (47.1%) patients showed elevated creatinine, and nine (52.9%) patients showed normal serum creatinine. None of the patients were treated with dialysis. Conclusions: IgG4-RKD was present in 27.4% of patients with AIP type 1, with male gender predominance. In cases of early diagnosis and cortisone treatment, the clinical course was mild in most cases. Regular laboratory control of renal function should be a part of the follow-up of patients with AIP type 1.

Diagnosis, treatment and long-term outcome of autoimmune pancreatitis in Sweden

INTRODUCTION

Autoimmune pancreatitis (AIP) is a pancreatic inflammatory process characterized by a strong inflammatory cell infiltration and two histopathologically distinct subtypes: type 1 and type 2. Diagnosis is often challenging and requires a combination of clinical, laboratory and imaging data. AIP can mimic pancreatic tumours leading to unnecessary resections if not correctly diagnosed. Short- and long-term outcomes of AIP have been poorly investigated so far and no large series have been previously reported from Sweden.

METHODS

A single-centre, retrospective, cohort study of patients with histologically confirmed or highly probable diagnosis of AIP according to ICDC criteria. Demographic, clinical and radiological characteristics, type of treatment and its outcomes were collected and analysed.

RESULTS

Seventy-one patients with AIP (87% with type 1), were evaluated at Karolinska University Hospital between 2004 and 2018; 49% males, mean age 49 years (range 44-53). Among them, 28% were histologically confirmed, 35% presented with jaundice, 22% with acute pancreatitis, 39% had non-specific symptoms such as weight loss or abdominal pain, 84% showed other organ involvement (OOI). Radiologically, 76% showed a focal pancreatic enlargement, 27% diffuse enlargement, 27% signs of acute pancreatitis and 10% of chronic pancreatitis. Overall, 58 patients (81%) underwent treatment with different medications: 46 (79%) cortisone, 7 (12%) azathioprine, 5 (8%) other immunosuppressive drugs. Twenty-six (36%) underwent biliary stenting and 12 (16%) were given surgery. In total, 47% of patients developed pancreatic exocrine insufficiency (PEI), of whom 76% had a severe form (faecal elastase-1 < 100 μg/g) and 21% of patients developed diabetes mellitus (pancreatic endocrine insufficiency), of whom 73% required insulin.

CONCLUSIONS

AIP is a challenging disease for diagnosis and treatment. Cortisone treatment is generally successful and provides clinical remission in the large majority of patients (>90%). In the further course of the disease, a considerable number of patients develop PEI and diabetes. Only one-quarter of patients exhibit on imaging the characteristic "sausage-like" pancreas (diffuse enlargement), approximately three-quarters had a focal mass that could be misdiagnosed as pancreatic malignancy.

Gastrointestinal and Extra-Intestinal Manifestations of IgG4-Related Disease

IgG4-related disease (IgG4-RD) is a chronic relapsing multi-organ fibro-inflammatory syndrome of presumed autoimmune etiology. It is characterized by increased serum levels of IgG4 and tissue infiltration by IgG4⁺ cells. Increased titers of autoantibodies against a spectrum of self-antigens and response to steroids have led to its characterization as an autoimmune disease. However, the pathognomonic antigens probably differ among manifestations, and different antigens or autoantibodies produce similar immune reactions in different organs. Little is known about the pathogenic effects, if any, of serum IgG4 or IgG4⁺ plasma cells in tissues. Despite several animal models of the disease, none truly recapitulates human IgG4-RD. Histologic analyses of tissues from patients with IgG4-RD reveal a dense lymphoplasmacytic infiltrate rich in IgG4⁺ plasma cells, storiform fibrosis, and obliterative phlebitis, although these features vary among organs. Typical presentation and imaging findings include mass-forming synchronous or metachronous lesions in almost any organ, but most commonly in the pancreas, bile duct, retroperitoneum, kidneys, lungs, salivary and lacrimal glands, orbit, and lymph nodes. In all organs, inflammation can be reduced by corticosteroids and drugs that deplete B cells, such as rituximab. Patients with IgG4-RD have relapses that respond to primary therapy. Intense fibrosis accompanies the inflammatory response, leading to permanent organ damage and insufficiency. Death from IgG4-RD is rare. IgG4-RD is a multi-organ disease with predominant pancreatico-biliary involvement. Despite its relapsing-remitting course, patients have an excellent prognosis.

Autoimmune pancreatitis: Imaging features

Background and Objectives

Autoimmune pancreatitis (AIP) remains a difficult disease to diagnose before treatment, particularly if presenting as a focal mass lesion. The purpose of this multicenter retrospective study is to analyze imaging features of histologically confirmed AIP to determine the additional diagnostic value of contrast-enhanced ultrasound (CEUS), contrast-enhanced endoscopic ultrasound (CE-EUS), and elastography to B-mode features.

Patients and Methods

We report on a retrospective data collection of 60 histologically confirmed cases of AIP in comparison to 16 patients with pancreatic adenocarcinomas (PDAC). All CE (-E) US examinations were assessed by two independent readers in consensus. The role of CEUS and CE-EUS for pancreatic evaluation was defined according to the 2011 European Federation of Societies for Ultrasound in Medicine and Biology guidelines.

Results

After injection of ultrasound (US) contrast agents, most AIP lesions displayed focal or diffuse isoenhancement (86.6%) in the arterial phase, while most of the PDAC lesions (93.7%) were hypoenhancing (P < 0.01). During the late phase, most AIP lesions were hyper-(65%) or iso-enhancing (35%), while most PDAC lesions were hypoenhancing (93.7%). CE-EUS was performed in a subset of ten patients and showed hyperenhancement in all AIP cases. Most focal AIP lesions (n = 27, 79.4%) were stiffer than the surrounding pancreatic parenchyma.

Conclusions

In this study, percutaneous and endoscopic contrast enhanced harmonic US techniques consistently revealed diffuse and focal types of AIP to have features consistent with vascularized lesions. Differentiation from the typically hypovascularized pancreatic adenocarcinoma was possible with CE (-E) US evaluation.

Features of Autoimmune Pancreatitis Associated With Inflammatory Bowel Diseases

BACKGROUND & AIMS

Few people know of autoimmune pancreatitis (AIP), a rare disorder associated with inflammatory bowel diseases (IBD). We aimed to describe phenotype and outcomes of IBD and AIP when associated.

METHODS

We performed a retrospective study of cases of AIP in IBD identified from the multicenter Groupe d'Etude Thérapeutique des Affections Inflammatoires du tube Digestif in Belgium and France from July 2012 through July 2015. Patients were diagnosed with AIP based on the International Consensus Diagnostic Criteria for AIP. A definitive AIP diagnosis was based on histological analysis of pancreatic resection specimens or samples collected by fine-needle aspiration during endoscopic ultrasound. Patients with probable type 1 AIP were identified based on imaging findings, clinical and/or radiologic responses to steroids, level of serum immunoglobulin G4, and involvement of other organs. Patients with probable type 2 AIP were identified based on imaging findings, clinical and/or radiologic responses to steroids, and association with IBD. The primary objective was to collect information on the characteristics of AIP in patients with IBD. We also compared features of patients with IBD with and without AIP in a case-control analysis, using multivariate analysis.

RESULTS

We analyzed data from 91 individuals with AIP and IBD (47 women) seen at 23 centers (58 had ulcerative colitis [UC] and 33 Crohn's disease [CD]). Eighty-nine patients had type 2 AIP, and 2 patients had type 1 AIP. The mean age at diagnosis of AIP was 35 ± 12 years, and for IBD it was 32 ± 12 years. AIP preceded IBD in 19 patients (21%). Over a mean follow-up period of 5.7 ± 4.9 years, 31 patients (34%) relapsed, 11 patients (12%) developed diabetes, and 17 patients (19%) developed exocrine pancreatic insufficiency. In patients with UC, factors independently associated with AIP included proctitis (odds ratio [OR], 2.9; 95% confidence interval [CI], 1.3-6.3; P = .007) and colectomy (OR, 7.1; 95% CI, 2.5-20; P = .0003). In patients with CD, AIP was significantly associated with fewer perianal lesions (OR, 0.16; 95% CI, 0.03-0.77; P = .023), non-stricturing non-penetrating CD (OR, 6.7; 95% CI, 1.25-33.3; P = .0029), and higher rate of colectomy (OR, 27.8; 95% CI, 3.6-217; P = .0029).

CONCLUSIONS

In a multicenter retrospective analysis of patients with AIP and IBD, followed for an average of 5.7 ± 4.9 years, we found most to have type 2 AIP. Two-thirds of patients have UC, often with proctitis. One-third of patients have CD, often with inflammatory features. Patients with IBD and AIP have higher rates of colectomy than patients with just IBD.

IgG4-related disease: long-term natural history and management of a relapsing multisystem disease entity

Although awareness of IgG4-related disease has grown over the past decade, with earlier diagnosis and treatment, understanding of its natural history over the long term and the optimal management remains unclear. We report the case of a 48-year-old man who presented with a pancreatic pseudotumour causing bile duct obstruction with coexisting autoimmune hepatitis and multisystem involvement. His symptoms settled on steroids and maintenance with azathioprine was commenced, however periodic relapses occurred involving multiple organs. A timeline-relating IgG4 levels, clinical features and immunosuppressive therapy are presented. The protean and relapsing-remitting nature of this condition is emphasised, and a brief review of long-term therapeutic options is provided.

Azathioprine Maintenance Therapy to Prevent Relapses in Autoimmune Pancreatitis

OBJECTIVES

Steroids are used to induce remission in autoimmune pancreatitis (AIP). Low-dosage steroid therapy or immunosuppressant (IMs) has been proposed as maintenance therapy to prevent AIP relapse. Few and conflicting data have been published on the efficacy of azathioprine (AZA) in preventing AIP relapse. The aim of this study was to evaluate the indication and efficacy of AZA as maintenance therapy to prevent disease relapse in AIP.

METHODS

Patients suffering from AIP diagnosed according to the ICDC in type 1, type 2, and not otherwise specified (NOS) were divided in those treated with AZA (AZA⁺ group) as maintenance therapy and not treated with maintenance therapy (AZA^- group). Exclusion criteria were: previous pancreatic surgery, other autoimmune diseases as indication for AZA treatment, and use of IMs different from AZA. Drug safety, clinical and instrumental outcome of AZA⁺ patients were evaluated.

RESULTS

A total of 23 patients (18 Males and 5 Females, mean age 54±11 years) in AZA⁺ group and 97 (58 Males and 39 Females, mean age 45±18 years) in AZA^- group were compared. In AZA⁺ group, patients were significantly older (P=0.043), type 1 AIP was more frequently diagnosed (87 vs. 51%, P=0.006), sIgG4 higher (758±625 vs. 311±409 mg/dl, P<0.001), other organ involvement (OOI) more frequently observed (83 vs. 48%, P=0.002), with higher frequency of relapse before AZA treatment (78 vs. 14%, P<0.001). Three patients in AZA⁺ group required drug discontinuation because of adverse events. Twenty patients were therefore evaluated for outcome. Six out of 20 patients (30%) relapsed after 24±15 months (5 in pancreas and 1 on biliary tract). They were retreated with steroids and continued AZA. Two out of 6 patients (33%) had a second relapse,after respectively 11 months (in pancreas and kidney) and 22 months (in kidney).

CONCLUSIONS

AZA is an effective and safe treatment to prevent AIP relapses.

Outcome and Genetic Factors in IgG4-Associated Autoimmune Pancreatitis and Cholangitis: A Single Center Experience

Introduction. Most investigations on autoimmune pancreatitis (AIP) were published on Asian cohorts while those on Caucasians are limited. However, there might be differences related to the origin. Patients and Methods. We analyzed 36 patients and compared type 1 (AIP1) with type 2 (AIP2). Results. The majority of patients suffered from AIP1 (55.6%). AIP1 patients were significantly older than AIP2 patients (54.4 versus 40.8 years). Moreover, 85.0% of AIP1 patients had concurrent autoimmune cholangitis (AIC) while 18.8% of AIP2 patients suffered from overlap to ulcerative colitis (UC). However, AIP1 patients revealed a cholestatic course and had significantly higher immunoglobulin G4 levels (IgG4). When compared to allele frequencies in healthy controls, in patients with AIP1 HLA-B8 reached statistical significance. Response to steroids was excellent in both groups, but we noticed high rates of relapse especially in AIP1 patients. Finally, 3 patients with AIP1 were diagnosed with cholangiocellular carcinoma (CCC). Conclusion. In contrast to Asian studies, we found an almost equal distribution of AIP1 and AIP2 patients in our German cohort. AIP2 patients were younger and mostly of female gender whereas AIP1 patients revealed higher IgG4 levels and involvement of the biliary tract in sense of IgG4-associated cholangitis.

The management of autoimmunity in patients with cholestatic liver diseases

Cholestatic liver diseases are rare diseases that often lead to cirrhosis and its consequent complications. In addition to liver-related morbidity, patients with cholestatic liver diseases often suffer from autoimmune diseases that affect several organs and tissues. The robust and efficient data collection and collaboration between hepatologists and rheumatologists have led to significant advancements in understanding the relationship between the cholestatic liver diseases and associated autoimmune diseases. In this paper, we discuss the cholestatic liver diseases (primary biliary cirrhosis, primary sclerosing cholangitis and immunoglobulin G4 associated cholangitis) and associated autoimmune diseases.

A case of autoimmune pancreatitis effectively treated with an immunosuppressant (azathioprine)

The patient was a 42-year-old man who presented at our hospital with obstructive jaundice. Although antinuclear antibody test results were negative, and immunoglobulin G4 (IgG4) was not elevated, endoscopic ultrasound revealed a mixed internal hyperechoic and diffuse hypoechoic pattern, a finding consistent with autoimmune pancreatitis. Endoscopic retrograde cholangiopancreatography further revealed irregular narrowing of the main pancreatic duct and sclerosing cholangitis with distal biliary stricture. In addition, endoscopic ultrasound with fine needle aspiration cytology resulted in a diagnosis of type 1 autoimmune pancreatitis. Oral prednisolone treatment was initiated at 30 mg/day, and the dosage was gradually decreased. However, in accordance with the patient's wishes, maintenance treatment was discontinued once dosage reached 5 mg/day. Despite this, relapse of obstructive jaundice occurred 1 month post discontinuation, and was treated with methyl-prednisolone pulse therapy (500 mg/day) followed by oral prednisolone. However, computed tomography, magnetic resonance imaging, and endoscopic ultrasound did not reveal sufficient improvement after 6 months of treatment. Therefore, an immunosuppressant (azathioprine) was introduced. Subsequent imaging analyses and endoscopic ultrasound fine needle aspiration revealed clear improvements in pathology.

Autoimmune Pancreatitis - A Riddle Wrapped in an Enigma

Autoimmune pancreatitis (AIP) was recognized as a clinical entity, at least in the West little more than 10 years ago. Since then, studies globally, and international collaboration, have led to important advances in our understanding of its clinical features, disease course, and management, although the aetiopathogenesis of this curious disease remains to be fully elucidated. Types 1 and 2 AIP have been described, of which type 1 is the commonest form, and best defined. International consensus now recognizes it as one of the many clinical manifestations of IgG4-related disease, and is now termed IgG4-related pancreatitis (IgG4-RP). The disease is not confined to a particular race, gender, or age, but often presents after the fifth decade in men. A common presentation is with jaundice due to low bile duct obstruction related to diffuse pancreatic enlargement (historically often leading to a misdiagnosis of cancer). Acute pancreatitis is unusual. Other organ involvement is a particular feature, including biliary disease, retroperitoneal fibrosis, generalized lymphadenopathy, renal, and lung involvement. No single test makes the diagnosis, and diagnostic criteria for type 1 AIP/IgG4-RP, which incorporate clinical, laboratory, radiological, pathological, and therapeutic parameters should be applied. A particular attempt should be made to make a histological diagnosis, which is characterized by an IgG4-positive lymphoplasmacytic infiltrate. Management is not based on randomized studies, but corticosteroids are the mainstay of treatment, providing rapid clinical and radiological benefit. However, clinical relapse is common (particularly in type 1 AIP, and in those with associated other organ involvement). Additional immunosuppression may be required, including azathioprine, and rituximab may play an emerging role. The disease course is variable, but loss of organ function (especially pancreatic exocrine failure and pancreatic atrophy) may occur.

Diagnosis, treatment and long-term outcomes of autoimmune pancreatitis in Spain based on the International Consensus Diagnostic Criteria: A multi-centre study

OBJECTIVES

Autoimmune pancreatitis (AIP) is a form of chronic pancreatitis that has been reported worldwide for the last two decades. The aim of this study is to analyse the clinical profile of patients from Spain with AIP, as well as treatments, relapses and long-term outcomes.

METHODS

Data from 59 patients with suspected AIP that had been diagnosed in 15 institutions are retrospectively analysed. Subjects are classified according to the International Consensus Diagnostic Criteria (ICDC). Patients with type 1 AIP (AIP1) and type 2 AIP (AIP2) are compared. Kaplan-Meier methodology is used to estimate the overall survival without relapses.

RESULTS

Fifty-two patients met ICDC, 45 patients were AIP1 (86.5%). Common manifestations included abdominal pain (65.4%) and obstructive jaundice (51.9%). Diffuse enlargement of pancreas was present in 51.0%; other organ involvement was present in 61.5%. Serum IgG4 increased in 76.7% of AIP1 patients vs. 20.0% in AIP2 (p = 0.028). Tissue specimens were obtained in 76.9%. Initial successful treatment with steroids or surgery was achieved in 79.8% and 17.3%, respectively. Maintenance treatment was given in 59.6%. Relapses were present in 40.4% of AIP1, with a median of 483 days. Successful long-term remission was achieved in 86.4%.

CONCLUSIONS

AIP1 is the most frequent form of AIP in Spain in our dataset. Regularly, ICDC allows AIP diagnosis without the need for surgery. Steroid and chirurgic treatments were effective and safe in most patients with AIP, although maintenance was required many times because of their tendency to relapse. Long-term serious consequences were uncommon.

Controversies in the management of primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) remains a rare but significant disease, which affects mainly young males in association with inflammatory bowel disease. There have been few advances in the understanding of the pathogenesis of the condition and no therapeutics with proven mortality benefit aside from liver transplantation. There remain areas of controversy in the management of PSC which include the differentiation from other cholangiopathies, in particular immunoglobulin G4 related sclerosing cholangitis, the management of dominant biliary strictures, and the role of ursodeoxycholic acid. In addition, the timing of liver transplantation in PSC remains difficult to predict with standard liver severity scores. In this review, we address these controversies and highlight the latest evidence base in the management of PSC.

The Long-Term Impact of Autoimmune Pancreatitis on Pancreatic Function, Quality of Life, and Life Expectancy

OBJECTIVE

To evaluate the long-term outcome of autoimmune pancreatitis.

METHODS

Patients with at least 2 years of follow-up were included. Information was collected regarding disease characteristics, treatment outcome, diagnosed malignancies, and mortality. In addition, pancreatic function and quality of life were assessed prospectively.

RESULTS

107 patients were included (87% men, 90% with type 1), with a median follow-up of 74 (interquartile range, 49-108) months. One third was operated for suspected pancreatic cancer (32%). Most patients were (successfully) treated with steroids (83%), but relapses were common (52%), for which no risk factors could be identified. Pancreatic carcinoma was not observed.Prospective data were obtained from 64%, as 17% had died, 7% were lost to follow-up, and 13% refused to participate. After a median of 75 (interquartile range, 50-106) months, 46% still used active treatment. Exocrine and endocrine insufficiencies were highly prevalent (82% and 57%, respectively). Quality of life and survival were not impaired, as compared with a reference population.

CONCLUSIONS

Despite an excellent initial treatment response, relapses are common, even in type 2, and almost half of the patients require maintenance therapy. Pancreatic insufficiency is highly prevalent, which calls for active screening. Pancreatic cancer was not observed, and quality of life and survival are not impaired.

Laparoscopic and Percutaneous Core Needle Biopsy Plays a Central Role for the Diagnosis of Autoimmune Pancreatitis in a Single-Center Study From Denmark

OBJECTIVES

The aims of this study were to describe the diagnosis of autoimmune pancreatitis (AIP) in Denmark and to test the usefulness of the International Consensus Diagnostic Criteria (ICDC) on a geographically well-defined cohort.

METHODS

All patients diagnosed with AIP at Odense University Hospital from 2007 to 2013 were included (n = 30; mean follow-up, 26.2 months). Data from laparoscopic or percutaneous ultrasound-guided core needle biopsy (CNB), resection specimens, endoscopic ultrasound (EUS), EUS-guided CNB, computed tomography, serum immunoglobulin G4 (IgG4), and pancreatography were retrospectively analyzed according to ICDC.

RESULTS

Twenty patients were diagnosed with type 1, 8 with type 2, and 2 with not otherwise specified AIP. Twenty-eight patients (93%) could correctly be classified when ICDC were retrospectively applied. Serum IgG4 was elevated in 44% of type 1 and 0% of type 2. Other organ involvement was observed in 40% of type 1 and 13% of type 2, but inflammatory bowel disease only in type 2 (P = 0.001). One patient had IgG4-related chronic perisplenitis as a hitherto undescribed manifestation of IgG4-related disease. Nineteen (91%) of 21 biopsied patients had diagnostic CNB features of AIP. Computed tomography, EUS, and pancreatography showed features highly suggestive or supportive of AIP in 68%, 72%, and 71%, respectively.

CONCLUSIONS

Laparoscopic or percutaneous ultrasound-guided CNB had the highest sensitivity for AIP. The ICDC could retrospectively correctly diagnose 93% of the patients.

Cerebral involvement in IgG4-related disease

IgG4-related disease is a recently recognised multi-system disease. Common organ involvement includes the pancreas, biliary tree and salivary glands. Central nervous system involvement has been infrequently reported. In a single-centre cohort of 84 patients, we report cerebral involvement in three (4%) patients. Details of cerebral involvement in these patients are outlined, including pituitary involvement in two patients and a diffuse autoimmune-like encephalopathy in the other.

Autoimmune pancreatitis in the context of IgG4-related disease: Review of imaging findings

Current understanding of autoimmune pancreatitis (AIP) recognizes a histopathological subtype of the disease to fall within the spectrum of IgG4-related disease. Along with clinical, laboratory, and histopathological data, imaging plays an important role in the diagnosis and management of AIP, and more broadly, within the spectrum of IgG4-related disease. In addition to the defined role of imaging in consensus diagnostic protocols, an array of imaging modalities can provide complementary data to address specific clinical concerns. These include contrast-enhanced computed tomography (CT) and magnetic resonance (MR) imaging for pancreatic parenchymal lesion localization and characterization, endoscopic retrograde and magnetic resonance cholangiopancreatography (ERCP and MRCP) to assess for duct involvement, and more recently, positron emission tomography (PET) imaging to assess for extra-pancreatic sites of involvement. While the imaging appearance of AIP varies widely, certain imaging features are more likely to represent AIP than alternate diagnoses, such as pancreatic cancer. While nonspecific, imaging findings which favor a diagnosis of AIP rather than pancreatic cancer include: delayed enhancement of affected pancreas, mild dilatation of the main pancreatic duct over a long segment, the “capsule” and “penetrating duct” signs, and responsiveness to corticosteroid therapy. Systemic, extra-pancreatic sites of involvement are also often seen in AIP and IgG4-related disease, and typically respond to corticosteroid therapy. Imaging by CT, MR, and PET also play a role in the diagnosis and monitoring after treatment of involved sites.

Does tobacco influence the natural history of autoimmune pancreatitis?

Tobacco recently appeared as a major independent factor adversely influencing the natural course of alcoholic chronic pancreatitis. However, the role of tobacco in patients with autoimmune pancreatitis (AIP) has never been studied. Type 2 AIP is associated with inflammatory bowel disease, especially ulcerative colitis in which smoking is protective. The aim of our study was to evaluate the influence of smoking on course of AIP.

PATIENTS AND METHODS

All consecutive patients followed in our centre for AIP according to ICDC were studied. Tobacco consumption was recorded. A relation between smoking and all event related to AIP was searched for.

RESULTS

96 patients with type 1 (73%) or type 2 (27%) AIP were included; 76% of patients were low smokers (never, ex- or smokers <10 p.y.) and 24% were high smokers (≥10 p.y.). The mean follow-up was 60 months [5-188]. AIP relapse was observed in 26% of patients. At the end-point, smokers ≥10 p.y. presented more frequently diabetes (50% vs 27%, p = 0.04) and imaging pancreatic damages (59% vs 34%, p = 0.02) than low smokers. There was also a non significant tendency to observe more frequently exocrine insufficiency and relapse in smokers ≥10 pack-year. No protective effect of smoking was observed in the subgroup of patients with type 2 AIP and ulcerative colitis.

CONCLUSIONS

In patients with AIP, high tobacco intake is associated with the risk of imaging pancreatic damages and with the occurrence of diabetes. Smoking cessation should be recommended.

Autoimmune pancreatitis: pathogenesis, latest developments and clinical guidance

Recently, autoimmune pancreatitis has been classified into two subtypes. Type 1 is related to immunoglobulin G4 and type 2 is related to granulocytic epithelial lesions, but pathogenetic mechanisms in both still remain unclear. Apart from type 2 autoimmune pancreatitis, the pathological features of type 1 autoimmune pancreatitis with increased serum immunoglobulin G4/immunoglobulin E levels, abundant infiltration of immunoglobulin G4+plasmacytes and lymphocytes, fibrosis, and steroid responsiveness are suggestive of abnormal immunity such as allergy or autoimmunity. Although pathophysiological conditions seem to be different in each, both respond well to steroid drugs. After remission, the patients with type 1 autoimmune pancreatitis show high relapse rates (30-50% within 6-12 months), whereas those with type 2 autoimmune pancreatitis seldom relapse. After remission, the steroid maintenance therapy and therapeutic strategy for relapsing patients with type 1 is different among local expertise. In this paper, recent advances in pathogenesis and clinical guidance for therapy are discussed.

Hypophysitis due to IgG4-related disease responding to treatment with azathioprine: an alternative to corticosteroid therapy

PURPOSE

Fifteen cases of lymphocytic hypophysitis due to IgG4-related disease have been reported demonstrating marked improvement with corticosteroid therapy. This is the first case of IgG4-related hypophysitis demonstrating improvement with azathioprine, where corticosteroids were initially tried but ceased due to concern regarding enlargement of the pituitary infiltrate.

METHODS

Case description and review of 15 cases reported in the literature. A 40 year old male was diagnosed with IgG-4 related disease based on pituitary and lacrimal gland biopsies associated with raised serum concentration of IgG4. The patient was commenced on prednisolone 30 mg/day, as rapid response to prednisolone treatment has been described in the literature for other cases of IgG4-related hypophysitis. Over the next 3 months, prednisolone treatment resulted in a reduction of serum IgG4 levels, but repeat MRI scan showed an enlarging pituitary mass with new optic nerve compression. Azathioprine 75 mg twice daily was commenced and in the subsequent 3 months, IgG4 levels normalised (0.58 g/L) and MRI scan showed 50% shrinkage of the pituitary mass. After 10 months of azathioprine treatment the MRI showed a normal sized pituitary but persistence of the infraorbital nerve thickening.

CONCLUSIONS

Hypophysitis due to IgG4-related disease usually demonstrates prompt response to corticosteroids. This case highlights the need to image promptly after starting treatment to exclude an enlarging pituitary mass despite corticosteroid treatment. Alternative therapy with azathioprine can result in marked improvement. It should be remembered that IgG-4 related hypophysitis is part of a multi-organ disease.

Autoimmune pancreatitis: multidetector-row computed tomography (MDCT) and magnetic resonance (MR) findings in the Italian experience

Multidetector-row computed tomography (MDCT) and magnetic resonance (MR) imaging are currently the most frequently performed imaging modalities for the study of pancreatic disease. In cases of suspected autoimmune pancreatitis (AIP), a dynamic quadriphasic (precontrast, contrast-enhanced pancreatic, venous and late phases) study is recommended in both techniques. In the diffuse form of autoimmune pancreatitis (DAIP), the pancreatic parenchyma shows diffuse enlargement and appears, during the MDCT and MR contrast-enhanced pancreatic phase, diffusely hypodense and hypointense, respectively, compared to the spleen because of lymphoplasmacytic infiltration and pancreatic fibrosis. During the venous phase of MDCT and MR imaging, the parenchyma appears hyperdense and hyperintense, respectively, in comparison to the pancreatic phase. In the delayed phase of both imaging modalities, it shows retention of contrast media. A "capsule-like rim" may be recognised as a peripancreatic MDCT hyperdense and MR hypointense halo in the T2-weighted images, compared to the parenchyma. DAIP must be differentiated from non-necrotizing acute pancreatitis (NNAP) and lymphoma since both diseases show diffuse enlargement of the pancreatic parenchyma. The differential diagnosis is clinically difficult, and dynamic contrast-enhanced MDCT has an important role. In the focal form of autoimmune pancreatitis (FAIP), the parenchyma shows segmental enlargement involving the head, the body-tail or the tail, with the same contrast pattern as the diffuse form on both modalities. FAIP needs to be differentiated from pancreatic adenocarcinoma to avoid unnecessary surgical procedures, since both diseases have similar clinical and imaging presentation. The differential diagnosis is clinically difficult, and dynamic contrast-enhanced MDCT and MR imaging both have an important role. MR cholangiopancreatography helps in the differential diagnosis. Furthermore, MDCT and MR imaging can identify the extrapancreatic manifestations of AIP, most commonly biliary, renal and retroperitoneal. Finally, in all cases of uncertain diagnosis, MDCT and/or MR follow-up after short-term treatment (2-3 weeks) with high-dose steroids can identify a significant reduction in size of the pancreatic parenchyma and, in FAIP, normalisation of the calibre of the upstream main pancreatic duct.

Autoimmune pancreatitis: role of endoscopy in diagnosis and treatment

This review addresses the role of endoscopy in the diagnosis and treatment of autoimmune pancreatitis (AIP) and provides a diagnostic process for patients with suspected AIP. When should AIP be suspected? When can it be diagnosed without endoscopic examination? Which endoscopic approaches are appropriate in suspected AIP, and when? What are the roles of diagnostic endoscopic retrograde pancreatography, endoscopic biopsies, and IgG4 immunostaining? What is the proper use of the steroid trial in the diagnosis of AIP in patients with indeterminate computed tomography imaging? Should biliary stenting be performed in patients with AIP with obstructive jaundice?

Infiltration of peritumoural but tumour-free parenchyma with IgG4-positive plasma cells in hilar cholangiocarcinoma and pancreatic adenocarcinoma

BACKGROUND

Recently, new guidelines for diagnosing IgG4-associated cholangitis have been published devaluing the diagnostic significance of IgG4-positive plasma cells and steroid trials. We sought to evaluate the utility of IgG4-positive plasma cells in discriminating IgG4-associated cholangitis from hilar cholangiocarcinoma and autoimmune pancreatitis from pancreatic adenocarcinoma under conditions when malignancy is likely to be missed.

METHODS

Resection specimens obtained from patients with hilar cholangiocarcinoma, pancreatic adenocarcinoma or hepatocellular carcinoma were re-evaluated for IgG4-positivity. Histological analysis focussed on peritumoural but tumour-free sections. Perioperative biochemical and clinical data were reviewed.

RESULTS

Nineteen patients with hilar cholangiocarcinoma and 29 patients with pancreatic adenocarcinoma were eligible for histological re-evaluation. Six of 19 (32%) patients with hilar cholangiocarcinoma and 5 of 29 (17%) patients with pancreatic adenocarcinoma were IgG4-positive (≥20 IgG4-positive plasma cells per high power field). Patients with IgG4-positive hilar cholangiocarcinoma showed significantly higher levels of serum total bilirubin (3.6mg/dl vs. 1.8mg/dl; P<0.05) and serum alanine-aminotransferase (median 343U/l vs. 63U/l, P<0.05) compared to IgG4-negative patients with hilar cholangiocarcinoma.

CONCLUSIONS

IgG4-positive plasma cells are of limited utility especially in distinguishing hilar cholangiocarcinoma from IgG4-associated cholangitis even when combined with clinical parameters and may be misleading under conditions when malignancy is missed.

Novel endoscopic approaches in the diagnosis and management of biliary strictures

Indeterminate bilary strictures present the clinician with a wide differential diagnosis. Histological confirmation is usually required for treatment, but tissue acquisition remains challenging. Novel developments in endoscopic technology, such as single operator cholangioscopy and confocal endomicroscopy, have led to improvements in diagnostic accuracy in recent years. In patients with non-resectable malignant biliary obstruction, effective biliary decompression improves symptoms and enables patients to undergo palliative therapies. Improvements in endoscopic techniques, biliary stents and the development of local ablative techniques have led to further improvements in stent patency and survival in these patients. In this article, we review emerging diagnostic and therapeutic techniques for the endoscopic management of indeterminate biliary strictures.

Interstitial cystitis: another IgG4-related inflammatory disease?

Interstitial cystitis (IC) is a disease of undetermined etiology and pathogenesis. Inflammation is thought to play a key role in many patients, characteristically with an increase in mast cells within the detrusor muscle of the bladder. We observed that some patients with IC had prominent plasma cells in bladder tissue, which elicited our interest in their possible pathogenic role in patients with IC. A total of 44 cases of IC were collected, including 42 bladder biopsies and 2 cystectomies. Patient age ranged from 18 to 92 years (average age of 49.5 years) and included 7 male and 37 female patients. The histology and immunostains for IgG, IgG4 and tryptase were examined, and the results were correlated with clinical and cystoscopic findings. Four cases showed a significant increase in IgG4-positive plasma cells, with greater than 30 IgG4 plasma cells per high-power field and an IgG4/IgG ratio greater than 0.5. In addition, statistically significant differences were found between IC with IgG4-positive plasma cells vs IgG4-negative cases. The IgG4-positive patients were of older age and had increased severe inflammation and decreased bladder capacity as compared with the IgG4-negative patients. We propose that a subset of patients with IC may have an IgG4-related disease, and further study including serum IgG4 measurement is required to better define this relationship.

IgG4-associated cholangitis

IgG4-associated cholangitis is the hepatobiliary manifestation of a recently characterized inflammatory systemic disease, associated with increased IgG4 serum levels and IgG4-positive lymphoplasmacytic infiltration. Often, patients present with obstructive jaundice, and imaging reveals stenoses of the extrahepatic or intrahepatic bile ducts, often in association with parenchymal pancreatic findings and irregularities of the pancreatic duct. The histologic findings include lymphoplasmacytic infiltrates, on occasion resulting in tumefactive lesions (which can mimic malignancy), obliterative phlebitis, and fibrotic changes. Steroid treatment is the mainstay of management, but relapse is common after discontinuation of therapy or during tapering of steroids and may require further treatment.

Autoimmune pancreatitis: current concepts

Autoimmune pancreatitis (AIP) is a distinct type of chronic pancreatitis with unique clinical, pathological, serological, and imaging features. AIP usually presents with obstructive jaundice. Imaging studies often reveal enlargement of the pancreas with a pancreatic mass and strictures of the main pancreatic duct. Two subtypes of AIP have recently been identified. Type I AIP is more prevalent in elderly Asian males and is characterized by lymphoplasmacytic sclerosing pancreatitis, obliterative phlebitis, and infiltration of large numbers of IgG4-positive plasma cells. Type II AIP is more prevalent in Caucasians and is characterized by granulocyte epithelial lesions. Most patients with type I AIP have a significantly elevated serum IgG4 concentration, which is an important feature for diagnosis and for differentiating between AIP and other conditions such as pancreatic cancer. Extrapancreatic complications are common, such as sclerosing cholangitis, sclerosing sialadenitis, retroperitoneal fibrosis in type I AIP, and ulcerative colitis in type II AIP. A rapid response to glucocorticoids treatment is suggestive of AIP, but the relapse rate is high, warranting the use of immunosuppressant treatment. B-cell depletion with rituximab may be a promising therapy. The prognosis of AIP is generally benign if treated promptly, and spontaneous remission occurs in a proportion of patients.

Cholangiocarcinoma or IgG4-associated cholangitis: how feasible it is to avoid unnecessary surgical interventions?

OBJECTIVE

To evaluate the experience of a tertiary hepatopancreaticobiliary (HPB) center in the diagnostic approach and management of patients with suspicion of cholangiocarcinoma (CCa), focusing on excluding patients with IgG4-associated cholangitis (IAC) from unnecessary major surgical interventions.

METHODS

Between January 2008 and September 2010, a total number of 152 patients with suspicion of CCa underwent evaluation through a HPB multidisciplinary team meeting. Patients without tissue diagnosis were managed surgically or medically on the basis of probable presence of IAC as underlying pathology. Serology, immunostaining, and imaging were reviewed and analyzed according to the HISORt (Histology, Imaging, Serology, Other organ involvement, Response to therapy) criteria for IAC.

RESULTS

Tissue diagnosis during the diagnostic workup was achieved in 104 patients (68%), whereas the remaining 48 were classified as "highly suspicious for CCa" (n = 35) or as "probable IAC" (n = 13). Among 16 "highly suspicious for CCa" patients who underwent surgery, pathology revealed 2 patients harboring IAC (n = 1) and a benign chronic inflammatory biliary stricture (n = 1), respectively. Among the 13 patients with primarily medical management as "probable IAC," final diagnosis was CCa (n = 3) and IAC (n = 9), while 1 patient had no proven diagnosis. The accuracy of serum IgG4 for diagnosis of IAC reached 60%. Sensitivity and specificity of immunostaining for IAC in biopsy specimens were 56% and 89%, respectively. Imaging features suggesting IAC yielded sensitivity, specificity, and accuracy of 75%, 89%, and 83%, respectively. Initial imaging was revised at the referral institute in 75% of IAC patients (P = 0.009), while an isolated stricture (P = 0.038), a biliary mass (P = 0.006), and normal pancreas on computed tomography (P = 0.01) were statistically significant parameters for distinguishing between CCa and IAC. The mean time for establishing a diagnosis of IAC was 12.4 months (range: 2.5-32 months).

CONCLUSIONS

Differential diagnosis between CCa and IAC mandates high index of suspicion and low threshold for referral in high volume institutes. The delayed establishment of diagnosis particularly for CCa needs to be balanced versus avoiding unnecessary surgery for IAC. Imaging features may be most helpful for optimal management.

Autoimmune pancreatitis: an illustrated guide to diagnosis

Autoimmune pancreatitis (AIP) remains one of the rarer forms of pancreatitis but has become increasingly well recognized and widely diagnosed as it is an important differential, particularly due to the dramatic response to appropriate therapy. It is now best considered as part of a multisystem disease and the notion of "IgG4-related systemic sclerosing disease" has become widely recognized as the number of extra-pancreatic associations of AIP grows. More recently AIP has been classified into two subtypes: lymphoplasmacytic sclerosing pancreatitis (LPSP) and idiopathic duct-centric pancreatitis (IDCP) with distinct geographical, age and sex distributions for the two subtypes, in addition to different pathological characteristics. The role of imaging is crucial in AIP and should be considered in conjunction with clinical, serological, and histopathological findings to make the diagnosis. Radiologists are uniquely placed to raise the possibility of AIP and aid the exclusion of significant differentials to allow the initiation of appropriate management and avoidance of unnecessary intervention. Radiological investigation may reveal a number of characteristic imaging findings in AIP but appearances can vary considerably and the focal form of AIP may appear as a pancreatic mass, imitating pancreatic carcinoma. This review will illustrate typical and atypical appearances of AIP on all imaging modes. Emphasis will be placed on the imaging features that are likely to prove useful in discriminating AIP from other causes prior to histopathological confirmation. In addition, examples of relevant differential diagnoses are discussed and illustrated.

Autoimmune pancreatitis mimicking pancreatic cancer

Context:

Autoimmune pancreatitis is a particular type of pancreatitis of presumed autoimmune etiology, it is an entity distinct from all others forms of chronic pancreatitis, characterized by clinical, histopathological, radiographic, serologic and therapeutic features. This benign disease resembles pancreatic carcinoma both clinically and radiographically.

Case Report:

A 27-year-old man presented with obstructive jaundice and evocative image of pancreatic tumor. A pancreaticoduodenectomy (Whipple operation) was performed and pathological examination of the specimen diagnosed AIP. Patient responded well to a course of corticosteroids with resolution of clinical and biological disorders.

Conclusion:

Accurate and timely diagnosis of autoimmune pancreatitis is particularly important because steroid therapy is effective and pancreatic resection is not necessary.