Japanese consensus guidelines for management of autoimmune pancreatitis: III. Treatment and prognosis of AIP

Case report and review of literature: IgG4-gastroduodenitis in upper GI Crohn's disease: two separate entities or just a marker of disease severity?

A 20-year-old man was presented with ulcerative gastritis and duodenitis complicated by pyloric stenosis. Helicobacter pylori infection was excluded, and the lesions did not respond to treatment with proton pump inhibitors. No other parts of the intestinal tract showed signs of inflammation. Histopathological review showed signs of chronic inflammation with granuloma formation. A tentative diagnosis of isolated upper gastrointestinal (UGI) Crohn's disease was performed. However, additional work-up revealed significantly positive IgG4 staining as well as elevated IgG4 serum levels. Since granulomatous disease is unlikely in IgG4-related disease, an eventual diagnosis of overlapping IgG4-related disease and Crohn's disease (CD) was performed. Treatment with systemic steroids and anti-TNF in combination with azathioprine led to rapid symptomatic improvement. In this article, we review the available literature on IgG4-related gastroduodenitis, granulomatous gastritis, and upper GI CD. We suggest the possibility that IgG4-infiltration may be a marker of severely active inflammatory bowel disease rather than a separate disease entity.

Headaches and Vasculitis

Vasculitis refers to heterogeneous clinicopathologic disorders that share the histopathology of inflammation of blood vessels. Unrecognized and therefore untreated, vasculitis of the nervous system leads to pervasive injury and disability making this a disorder of paramount importance to all clinicians. Headache may be an important clue to vasculitic involvement of central nervous system (CNS) vessels. CNS vasculitis may be primary, in which only intracranial vessels are involved in the inflammatory process, or secondary to another known disorder with overlapping systemic involvement. Primary neurologic vasculitides can be diagnosed with assurance after intensive evaluation that incudes tissue confirmation whenever possible.

Autoimmune pancreatitis: Cornerstones and future perspectives

Autoimmune pancreatitis (AIP) is an autoimmune subtype of chronic pancreatitis resulting from the aberrant immune response against the pancreas, leading to inflammation and fibrosis. Although AIP is rare, its incidence is increasing and is often misdiagnosed as other pancreatic diseases. AIP is commonly classified into two types. Type 1 AIP (AIP-1) is typically associated with elevated serum immunoglobulin G4 (IgG4) levels and systemic manifestations, while type 2 AIP is typically a more localized form of the disease, and may coexist with other autoimmune disorders, especially inflammatory bowel diseases. Additionally, there is emerging recognition of a third type (type 3 AIP), which refers to immunotherapy-triggered AIP, although this classification is still gaining acceptance in medical literature. The clinical manifestations of AIP mainly include painless jaundice and weight loss. Elevated serum IgG4 levels are particularly characteristic of AIP-1. Diagnosis relies on a combination of clinical, laboratory, radiological, and histological findings, given the similarity of AIP symptoms to other pancreatic disorders. The mainstay of treatment for AIP is steroid therapy, which is effective in most cases. Severe cases might require additional imm-unosuppressive agents. This review aims to summarize the current knowledge of AIP, encompassing its epidemiology, etiology, clinical presentation, diagnosis, and treatment options. We also address the challenges and controversies in diagnosing and treating AIP, such as distinguishing it from pancreatic cancer and managing long-term treatment, highlighting the need for increased awareness and knowledge of this complex disease.

Systemic vasculitis and headache

PURPOSE OF REVIEW

Vasculitis refers to heterogeneous clinicopathologic disorders that share the histopathology of inflammation of blood vessels. Unrecognized and therefore untreated, vasculitis of the nervous system or so called neurovasculitides, lead to pervasive injury and disability making these disorder of paramount importance to clinicians.

RECENT FINDINGS

Headache is an important clue to vasculitic involvement of central nervous system (CNS) vessels. CNS vasculitis may be primary, in which only intracranial vessels are involved in the inflammatory process, or secondary to another known disorder with overlapping systemic involvement. A suspicion of vasculitis based on the history, clinical examination, or laboratory studies warrants prompt evaluation and treatment to forestall progression and avert cerebral ischemia or infarction. There has been remarkable progress in the pathogenesis, diagnosis, and treatment of primary adult and pediatric CNS vasculitides predicated on achievements in primary systemic forms.

SUMMARY

Vasculitis can be diagnosed with certainty after intensive evaluation that includes tissue confirmation whenever possible. Clinicians must choose from among the available immune modulating, suppressive, and targeted immunotherapies to induce and maintain remission status and prevent relapse, tempered by the recognition of anticipated medication side effects.

IgG4-related digestive diseases: diagnosis and treatment

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

Potential relationship between the dosage of prednisolone and delayed healing at tooth extraction: A retrospective study

Background/purpose

Delayed healing of the extraction socket is not uncommon when tooth extraction is performed on patients taking prednisolone. This study aimed to identify specific dosage of prednisolone and factors associated with delayed healing of the extraction socket in patients taking prednisolone.

Materials and methods

This single-center retrospective study included 80 patients who underwent tooth extraction under local anesthesia and were taking prednisolone orally. Patients were divided into the nondelayed healing group (n = 50) and delayed healing group (n = 30), and their background and dosage of prednisolone were compared.

Results

The dosage of prednisolone was significantly higher in the delayed healing group than in the nondelayed healing group. A receiver operating characteristics curve analysis resulted in moderate accuracy when the cutoff value was set at 8.0, with 67% sensitivity, 76% specificity, and 0.765 area under the curve. The multivariate logistic regression analysis revealed that prednisolone dosage >8.0 mg/day (odds ratio [OR], 10.8; 95% confidence interval [CI], 2.79-41.6) and osteosclerotic changes beyond the alveolar bone around the tooth to be extracted (OR, 10.3; 95% CI, 2.81-37.8) in X-ray imaging had significant effects on delayed healing.

Conclusion

The results of this study suggested that delayed healing following tooth extractions in patients taking prednisolone was related to a dosage of 8.0 mg/day or higher and osteosclerotic changes.

Autoimmune pancreatitis with IgG-4 cholangiopathy in a pregnant woman: A case report

Diagnosis and management of autoimmune pancreatitis during pregnancy. Autoimmune pancreatitis is a rare and life-threatening condition with increased maternal and fetal morbidity and mortality. Autoimmune pancreatitis may result in a mass-forming lesion in the pancreas resembling pancreatic cancer; therefore, meticulous and careful investigations must be done to avoid misdiagnosing autoimmune pancreatitis as pancreatic cancer. Since autoimmune pancreatitis improves dramatically to steroid therapy, accurate diagnosis of autoimmune pancreatitis can avoid unnecessary procedures, surgeries, and pancreatic resection. A case of a pregnant lady in her third trimester was presented with abdominal pain, nausea, and vomiting. On examination, there was tenderness in both epigastric and right hypochondrium associated with elevated serum amylase, liver transaminases, alkaline phosphatase, gamma-glutamyl transpeptidase, and immunoglobulin G4. Both abdominal ultrasound and magnetic resonance cholangiopancreatography showed a pancreatic head lesion with dilation in both pancreatic duct and common bile duct. Steroid was initiated that resulted in rapid and dramatic responsiveness. Acute pancreatitis is uncommon during pregnancy, and autoimmune pancreatitis is a very rare form of acute pancreatitis; therefore, a clear and rapid assessment, diagnosis, and management plan are necessary to avoid maternal and fetal morbidity and mortality.

Characteristics of mass-forming autoimmune pancreatitis commonly misdiagnosed as a malignant tumor

Objective

This study aimed to explore the clinical characteristics and differential diagnosis of patients with autoimmune pancreatitis (AIP) and pancreatic cancer to prevent misdiagnosis and mistreatment.

Methods

The clinical data of patients with AIP with suspected pancreatic or bile duct malignancy and pancreatic cancer were retrospectively analyzed. The risk factors and the diagnostic value of IgG4 and Tbil levels before treatment for AIP was investigated. Moreover, the imaging features and response to hormone therapy were analyzed.

Results

AIP was commonly observed in men. Compared to patients with pancreatic cancer, the incidence of poor appetite and weight loss and carbohydrate antigen 19-9 (CA19-9) level was lower in patients with AIP, while the immunoglobulin G4 (IgG4) level was higher (p < 0.05). After treatment, the IgG4 and CA19-9 levels in patients with AIP were decreased (p < 0.001). IgG4 level before treatment (OR = 2.452, 95%CI: 1.180-5.096, P = 0.016) and total bilirubin (Tbil) level before treatment (OR = 0.992, 95%CI: 0.985-0.998, P = 0.013) were independent risk factors of AIP. Furthermore, the diagnostic value of IgG4 level before treatment, Tbil level before treatment, IgG4/Tbil before treatment, and a combination of these indicators was high. Moreover, 15 (68.18%) patients with AIP had space-occupying lesions of the pancreas, and 16 (72.73%) had autoimmune cholangitis. Most patients with AIP were sensitive to hormone therapy.

Conclusions

The Tbil and IgG4 levels, imaging findings, and hormone therapy reactivity could differentiate AIP from pancreatic cancer. A combination of IgG4, Tbil, and IgG4/Tbil before treatment might be a promising diagnostic biomarker for AIP.

Challenges for clinicians treating autoimmune pancreatitis: Current perspectives

Autoimmune pancreatitis (AIP) is a rare disease clinically characterized by obstructive jaundice, unintentional weight loss, acute pancreatitis, focal pancreatic mass, and diabetes. AIP is classified into two subtypes - type 1 and type 2 - according to pathological findings, clinical features, and serology test results, but some cases may be defined as type not otherwise in the absence of pathological findings and inflammatory bowel disease. To address the differences in diagnostic criteria by country, standard diagnostic criteria for AIP were proposed in 2011 by an international consensus of expert opinions. Differential diagnosis of AIP from pancreatic ductal adenocarcinoma is important but remains challenging for clinicians. Fortunately, all subtypes of AIP show dramatic response to steroid treatment. This review discusses the current perspectives on the diagnosis and management of AIP in clinical practice.

Clivus-involved immunoglobulin G4 related hypertrophic pachymeningitis mimicking meningioma: A case report

BACKGROUND

Immunoglobulin G4 related disease (IgG4-RD) is a fibroinflammatory disease with markedly elevated serum IgG4 levels and fibrous tissue proliferation, accompanied by numerous plasma cells. IgG4 related hypertrophic pachymeningitis (IgG4-RHP) is relatively rare and indistinguishable from other phymatoid diseases before the operation. The risk of long-term immunosuppression needs to be balanced with disease activity.

CASE SUMMARY

A 40-year-old man presented with headache and bilateral abducent paralysis. He was also diagnosed with pulmonary tuberculosis 10 years ago and was on regular treatment for the same. Before the operation and steroid therapy, the patient was suspected of having tubercular meningitis at a local hospital. A clivus lesion was found via brain magnetic resonance imaging (MRI) at this presentation. He was preliminarily diagnosed with meningioma and underwent Gamma Knife Surgery. Transnasal endoscopic resection was performed to treat deterioration of nerve function. Postoperative pathologic examination suggested IgG4-RD. Moreover, the serum IgG4 was elevated at 1.90 g/L (reference range: 0.035-1.500 g/L). After steroid therapy for 2 mo, the lesion size diminished on MRI, and the function of bilateral abducent nerves recovered.

CONCLUSION

IgG4-RHP is relatively rare and indistinguishable before the operation. Elevated serum IgG4 levels and imaging examination help in the diagnosis of IgG4-RHP. Surgery is necessary when lesions progress and patients start to develop cranial nerve function deficit.

Improvement of Mass Lesions around Coronary Arteries and Fractional Flow Reserve after Steroid Therapy in Immunoglobulin-G4-related Coronary Periarteritis

Immunoglobulin-G4-related disease (IgG4-RD) is a multi-organ systemic inflammatory disorder. The ideal treatment of coronary artery involvement in IgG4-RD remains uncertain due to its rarity. We herein report a case of coronary artery involvement with IgG4-RD, wherein mass lesions surrounded the coronary arteries with a moderate stenosis lesion in the right coronary artery (RCA). The fractional flow reserve (FFR) of the RCA was 0.76. After steroid therapy, the mass lesions around the coronary arteries improved. The FFR of the RCA also improved from 0.76 to 0.86. These findings suggest the efficacy of using steroid therapy for coronary artery involvement with IgG4-RD.

Update on classification, diagnosis, and management of immunoglobulin G4-related disease

Immunoglobulin G4-related disease (IgG4-RD) is a newly recognized chronic fibro-inflammatory autoimmune disease, and its recognition has been constantly increasing worldwide over the last few years. A correct and timely recognition, as well as appropriate intervention, is crucial for the treatment of IgG4-RD. For certain subtypes of IgG4-RD, organ-specific criteria are formulated to make the diagnosis more accurate. New biomarkers have emerged in the recent years to aid the disease diagnosis, its prognosis prediction, as well as therapy response monitoring. Although recurrence is very common in IgG4-RD, glucocorticoid is still the first-line treatment for the majority of patients. The factors that affect the likelihood of disease relapse are multifaceted. The selection strategy of various steroid-sparing agents is still being explored. Besides, when patients have special sites involvement leading to severe clinical conditions, surgical operation or interventional therapy should also be considered. An update on classification, diagnosis, and management of IgG4-RD is provided in the current study to fully elucidate the recommended clinical practice of this mysterious disease.

IgG4-Related Disease: A Clinical Case Series From a Tertiary Care Center in India

AIM

Immunoglobulin G4-related disease (IgG4-RD) is often an unrecognized, rare fibroinflammatory condition that can involve various organ systems. This study aimed to identify the different clinical patterns of this disease in a single center in North India.

METHODS

Patients were diagnosed on the basis of published diagnostic criteria for IgG4-RD. Patients' presenting complaints; epidemiologic profiles; and laboratory, radiologic, and histologic findings along with the treatment and outcomes were collected and analyzed.

RESULTS

In total, 70 patients were diagnosed with the disease. The female-to-male ratio was 0.94:1, and it increased with multiorgan involvement. The mean age of patients was 41.4 years, and the majority of the patients (65.7%) were younger than 50 years. Patients were diagnosed as possible (38.57%), probable (32.85%), and definite (28.57%) IgG4-RD. The incidence of the involvement of orbital and periorbital tissues was the highest (52.9%); however, 13% of the patients had multiple organ involvement. Patients with involvement of the retroperitoneal tissues and the lymph nodes were 8.5% and 5.7%, respectively. Increased serum IgG4 levels were found in 74.3% of the patients with single-organ involvement, whereas all patients with multiorgan involvement had increased IgG4 levels. The majority of patients (94.3%) required immunosuppressive medications along with corticosteroids. Azathioprine was the most commonly used (72.8%) immunosuppressive medication. Rituximab was used in 17.1% of the patients, of whom only one had multisystem involvement.

CONCLUSIONS

This study depicts the most common patterns of organ involvement, along with the epidemiologic, laboratory, histologic, and radiologic data and response to treatment, in IgG4-RD, with a definite ophthalmology referral bias.

Amendment of the Japanese consensus guidelines for autoimmune pancreatitis, 2020

In response to the latest knowledge and the amendment of the Japanese diagnostic criteria for autoimmune pancreatitis (AIP) in 2018, the Japanese consensus guidelines for managing AIP in 2013 were required to be revised. Three committees [the professional committee for developing clinical questions (CQs) and statements by Japanese specialists; the expert panelist committee for rating statements by the modified Delphi method; and the evaluating committee of moderators] were organized. Twenty specialists in AIP extracted the specific clinical statements from a total of 5218 articles (1963-2019) from a search in PubMed and the Cochrane Library. The professional committee made 14, 9, 5, and 11 CQs and statements for the current concept and diagnosis, extra-pancreatic lesions, differential diagnosis, and treatment, respectively. The expert panelists regarded the statements as valid after a two-round modified Delphi approach with individually rating these clinical statements, in which a clinical statement receiving a median score greater than 7 on a 9-point scale from the panel was regarded as valid. After evaluation by the moderators, the amendment of the Japanese consensus guidelines for AIP has been proposed in 2020.

Efficacy and safety of rituximab in autoimmune pancreatitis type 1: our experiences and systematic review of the literature

INTRODUCTION

Autoimmune pancreatitis (AIP) is a special form of pancreatitis that responds well to glucocorticoid (GC) treatment. Relapses of AIP are common. The anti-CD20 antibody rituximab (RTX) has shown promising results in GC refractory cases, but long-term data are scarce. The study aims to determine the clinical and imaging response to RTX and summarize the existing data on RTX therapy in patients with AIP type 1 in the literature.

PATIENTS AND METHODS

Retrospective analysis of electronic medical records was conducted. Additionally, we conducted a systematic review of the literature concerning RTX use in AIP type 1.

RESULTS

Twelve (11.7%) of 103 patients with AIP type 1 were treated with RTX during the study period: eight (66.7%) achieved complete and four (33.3%) partial remission. RTX was discontinued in one patient who developed fever and reactivation of latent tuberculosis. None of the remaining 11 patients relapsed during a median follow-up of 17 months. No significant differences were detected in baseline clinical characteristics or history of relapse between the patients who obtained complete and partial remission. Altogether, eight studies with 110 AIP type-1 patients treated with RTX were analyzed. Adverse effects ranged from 11-43% and the relapse-free period during follow-up (range 2-173 months) ranged from 38-94%.

CONCLUSIONS

Our results confirm that RTX is efficacious in the treatment of AIP type 1 by inducing remission and preventing relapse. In addition, there are few adverse effects of the treatment.

Determination of the duration of glucocorticoid therapy in type 1 autoimmune pancreatitis: A systematic review and meta-analysis

BACKGROUND

The indications for maintenance glucocorticoid therapy (MGT) and its duration after initial remission of type 1 autoimmune pancreatitis (AIP) remain controversial. In contrast to the Japanese treatment protocol, the Mayo protocol does not recommend MGT after initial remission. This study aimed to evaluate the relapse rate in patients with type 1 AIP according to the duration of glucocorticoid therapy.

METHODS

We conducted a systematic literature review up until November 30, 2020, and identified 40 studies reporting AIP relapse rates. The pooled relapse rates were compared between groups according to the protocol and duration of glucocorticoids (routine vs. no MGT; glucocorticoids ≤6 months vs. 6-12 months vs. 12-36 months vs. ≥ 36 months). The pooled rates of adverse events related to glucocorticoids were also evaluated.

RESULTS

Meta-analysis indicated calculated pooled relapse rates of 46.6% (95% confidence interval (CI), 38.9-54.3%) with glucocorticoids for ≤ 6 months, 44.3% (95% CI, 38.8-49.8%) for 6-12 months, 34.1% (95% CI, 28.6-39.7%) for 12-36 months, and 27.0% (95% CI, 23.4-30.6%) for ≥ 36 months. The rate of relapse was also significantly lower in patients with routine-use protocol of MGT (31.2%; 95% CI, 27.5-34.8%) than in patients with no MGT protocol (44.1%; 95% CI, 35.8-52.4%). Adverse events were comparable between groups.

CONCLUSIONS

The rate of relapse tended to decrease with extended durations of glucocorticoid therapy up to 36 months. Clinicians may decide the duration of glucocorticoids according to patient condition, including comorbidities and risk of relapse.

IgG4-related disease: an atypical presentation of steroid-responsive renal mass

IgG₄-related disease (IgG₄-RD) is a systemic fibroinflammatory disease characterised by dense lymphoplasmacytic infiltration rich in IgG₄-positive plasma cells, storiform fibrosis and obliterative phlebitis. Serum IgG₄ levels are typically elevated but half of the patients had normal serum IgG₄ levels. IgG₄-RD represents a spectrum of diseases that involve various organs such as the pancreas, liver, kidneys, and salivary glands often manifesting as diffuse organ enlargement or a mass-like lesion mimicking cancer. An increased incidence of malignancy among patients with IgG₄-RD has been reported. Thus, differentiating malignancy from IgG₄-RD manifestation is important as the treatment differs. Glucocorticoids are considered first-line therapy and should be started early to prevent fibrosis. Patients usually have an excellent clinical response to steroids, and poor steroid response is indicative of an alternative diagnoses such as malignancy. This case report describes a case of IgG₄-RD with renal mass in a young man that resolved with glucocorticoid therapy alone.

Autoimmune pancreatitis: Current perspectives

Over the last two decades, our knowledge and understanding regarding the pathogenesis and biology of autoimmune pancreatitis (AIP) have improved tremendously. Type 1 AIP or IgG4-related pancreatitis (IgG4-RP) is now believed to be the prototype of the multisystemic IgG4-related disease. In view of clinical features like obstructive jaundice and mass-forming lesions in the pancreas in elderly men, type 1 AIP often mimics pancreatic cancer. IgG4-related sclerosing cholangitis concomitantly involving the extrahepatic and intrahepatic biliary tree is the most common extrapancreatic involvement seen in up to 80% of these patients, which needs to distinguish from cholangiocarcinoma. Histology is characterised by lymphoplasmacytic inflammation, abundant IgG4 positive plasma cell infiltration, storiform fibrosis and obliterative phlebitis. Apart from histology, high serum IgG4 levels, pancreatic parenchymal and duct imaging findings and other organ involvement aid in diagnosis especially in cases where definitive histology is not evident. Also, these parameters lay the foundation of various diagnostic criteria proposed over last few years. On the contrary, histology alone is the mainstay for establishing diagnosis of idiopathic duct-centric pancreatitis (IDCP) as it lacks any specific serological marker or imaging. Since both types of AIP respond dramatically to corticosteroid treatment, a biopsy is crucial to establish the preoperative diagnosis and to exclude malignancy so as to avoid unnecessary surgery. This review discusses the morphologic spectrum, treatment and prognosis of IgG4-RP and IDCP with an emphasis on approach to diagnosis with relevant histologic features, differential diagnoses and the challenges faced during biopsy interpretation.

Role of Endoscopic Ultrasonography-Guided Fine Needle Aspiration/Biopsy in the Diagnosis of Autoimmune Pancreatitis

Type 1 autoimmune pancreatitis (AIP) is histologically characterized by lymphoplasmacytic sclerosing pancreatitis (LPSP). Recently, the diagnostic yield of endoscopic ultrasonography-guided fine needle aspiration/biopsy (EUS-FNA/B) for AIP has been reported. However, its role in the diagnostic flow of AIP is not fully elucidated. We retrospectively reviewed 53 consecutive patients who were suspected with AIP and underwent EUS-FNA/B. We evaluated the contribution of EUS-FNA/B to the diagnosis of AIP before considering response to steroid therapy among patients with diffuse enlargement of the pancreas and those with focal enlargement, respectively. Twenty-two patients showed diffuse pancreatic enlargement and 31 showed focal enlargement. The final diagnosis was definitive AIP in 32 patients, probable AIP in 2, possible AIP in 1, and mass-forming focal pancreatitis in 18. There was no change in diagnosis after EUS-FNA/B among patients with diffuse pancreatic enlargement, while diagnosis changed in 38.7% (12/31) among those with focal enlargement—there was a probable to definitive diagnosis in 4 patients, unspecified to definitive in 3, and unspecified to probable in 5. EUS-FNB provided a significantly higher sensitivity for typical pathological findings of LPSP than EUS-FNA, and 10 patients were diagnosed as pathologically definitive AIP by EUS-FNB, though none were by EUS-FNA (p = 0.002). EUS-FNA/B was useful in the diagnosis of focal type AIP, and steroid therapy could be introduced after the diagnosis was confirmed. Meanwhile, EUS-FNA/B provided no contribution to diagnosis of diffuse type AIP. EUS-FNB showed a higher diagnostic yield than FNA.

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

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

Prediction of 3-month treatment outcome of IgG4-DS based on BP artificial neural network

OBJECTIVE

The study aimed to establish an effective back-Propagation artificial neural network (BP-ANN) model for automatic prediction of 3-month treatment outcome of IgG4-DS.

METHODS

A total of 26 IgG4-DS patients at Shanghai Ninth People's Hospital from January 2018 to December 2019 were involved in the study. They were all followed for >3 months. The primary outcome was reduction of serum IgG4 (sIgG4) after 3-month treatment. The association between risk factors and reduction of sIgG4 was analyzed by Spearman's rank correlation test. According to the R values, we built a BP-ANN model by MATLAB R2019b.

RESULTS

The average reduction of sIgG4 was 5.55 ± 5.03. After Spearman's rank correlation test, ESR, sIgG4, and sIgG were independently associated with reduction of sIgG4 (p < .05) and were selected as input variables. Take into account these parameters, BP-ANN model was developed and the coefficient of determination (R² ) model was 0.95512.

CONCLUSION

The BP-ANN model based on ESR, sIgG4, and sIgG could predict the 3-month reduction of sIgG4 for IgG4-DS patients. It showed potential clinical application value.

Immunoglobulin G4-related disease in the stomach presenting as a gastric subepithelial tumor: Case report

INTRODUCTION

Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated fibroinflammatory disorder characterized by specific pathologic findings and often, but not in all cases, elevated serum IgG4 concentration. Although it can virtually involve every organ system, cases involving the gastrointestinal tract and especially gastric mass lesions have rarely been reported.

PATIENT CONCERNS

A 45-year-old man, who was incidentally discovered asymptomatic subepithelial tumor (SET), by endoscopy, on the greater curvature of the upper gastric body, was referred to our hospital for further evaluation.

DIAGNOSIS

The patient was postoperatively diagnosed with IgG4-RD by histopathologic results.

INTERVENTIONS

The patient underwent laparoscopic wedge resection.

OUTCOMES

The patient is presently followed up annually in our clinic and had no problems and showed no signs of recurrence in examination.

CONCLUSION

We reported a rare case of IgG4-RD presenting as a gastric SET. The first line treatment of IgG4-RD is glucocorticoid administration. However, because pathologic examination is challenging owing to the lesion location, preoperative diagnosis is difficult and may lead to unnecessary gastric resection. Thus, using alternative preoperative diagnostic methods such as endoscopic ultrasound-guided fine-needle biopsy or the biopsy unroofing technique could spare the patient from unnecessary surgical treatment.

The eosinophilic esophagitis and IgG4-related disease involving the esophagus

The study of eosinophilic esophagitis has become a dynamic field with an evolving understanding of the pathogenesis, diagnosis, and treatment. Immunoglobulin G4 (IgG4)-related disease exhibits systemic involvement but very rarely involves the esophagus. The article presents a clinical case: the history of ulcer and stricture of the esophagus in a young man of 17 years. The patient was finally diagnosed with IgG4-related and eosinophilic esophagitis and showed a good response to corticosteroid therapy. We herein report a rare case of dysphagia associated with IgG4-related disease and eosinophilic. We presented a review of modern data on the relationship of eosinophilic esophagitis and pathological IgG4-response.

Diagnosis and treatment of autoimmune and IgG4-related hypophysitis: clinical guidelines of the Japan Endocrine Society

Hypophysitis, which is often accompanied by pituitary dysfunction, is classified into several subtypes based on the cause, histology, and the location of inflammation in the pituitary gland. A definitive diagnosis requires pituitary biopsy, which is invasive, and the process is limited to specialized clinical settings. In this opinion paper, we review the literature associated with hypophysitis, and provide the guidelines of the Japan Endocrine Society for the diagnosis and treatment of autoimmune and IgG4-related hypophysitis.

Steroid Therapy and Steroid Response in Autoimmune Pancreatitis

Autoimmune pancreatitis (AIP), a unique subtype of pancreatitis, is often accompanied by systemic inflammatory disorders. AIP is classified into two distinct subtypes on the basis of the histological subtype: immunoglobulin G4 (IgG4)-related lymphoplasmacytic sclerosing pancreatitis (type 1) and idiopathic duct-centric pancreatitis (type 2). Type 1 AIP is often accompanied by systemic lesions, biliary strictures, hepatic inflammatory pseudotumors, interstitial pneumonia and nephritis, dacryoadenitis, and sialadenitis. Type 2 AIP is associated with inflammatory bowel diseases in approximately 30% of cases. Standard therapy for AIP is oral corticosteroid administration. Steroid treatment is generally indicated for symptomatic cases and is exceptionally applied for cases with diagnostic difficulty (diagnostic steroid trial) after a negative workup for malignancy. More than 90% of patients respond to steroid treatment within 1 month, and most within 2 weeks. The steroid response can be confirmed on clinical images (computed tomography, ultrasonography, endoscopic ultrasonography, magnetic resonance imaging, and 18F-fluorodeoxyglucose-positron emission tomography). Hence, the steroid response is included as an optional diagnostic item of AIP. Steroid treatment results in normalization of serological markers, including IgG4. Short- and long-term corticosteroid treatment may induce adverse events, including chronic glycometabolism, obesity, an immunocompromised status against infection, cataracts, glaucoma, osteoporosis, and myopathy. AIP is common in old age and is often associated with diabetes mellitus (33-78%). Thus, there is an argument for corticosteroid therapy in diabetes patients with no symptoms. With low-dose steroid treatment or treatment withdrawal, there is a high incidence of AIP recurrence (24-52%). Therefore, there is a need for long-term steroid maintenance therapy and/or steroid-sparing agents (immunomodulators and rituximab). Corticosteroids play a critical role in the diagnosis and treatment of AIP.

Chronic Meningitis

PURPOSE OF REVIEW

This article describes the clinical presentation, diagnostic approach (including the use of novel diagnostic platforms), and treatment of select infectious and noninfectious etiologies of chronic meningitis.

RECENT FINDINGS

Identification of the etiology of chronic meningitis remains challenging, with no cause identified in at least one-third of cases. Often, several serologic, CSF, and neuroimaging studies are indicated, although novel diagnostic platforms including metagenomic deep sequencing may hold promise for identifying organisms. Infectious etiologies are more common in those at risk for disseminated disease, specifically those who are immunocompromised because of human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS), transplantation, or immunosuppressant medications. An important step in identifying the etiology of chronic meningitis is assembling a multidisciplinary team of individuals, including those with specialized expertise in ophthalmology, dermatology, rheumatology, and infectious diseases, to provide guidance regarding diagnostic procedures.

SUMMARY

Chronic meningitis is defined as inflammation involving the meninges that lasts at least 4 weeks and is associated with a CSF pleocytosis. Chronic meningitis has numerous possible infectious and noninfectious etiologies, making it challenging to definitively diagnose patients. Therefore, a multifaceted approach that combines history, physical examination, neuroimaging, and laboratory analysis, including novel diagnostic platforms, is needed. This article focuses on key aspects of the evaluation of and approach to patients with chronic meningitis. Specific infectious etiologies and differential diagnoses of subacute and chronic meningitis, including noninfectious etiologies, are addressed.

Overview of the Vasculitides

The systemic vasculitides are heterogeneous clinicopathologic disorders that share the common feature of vascular inflammation. The resulting disorder can vary depending on involvement of specific organs, caliber of blood vessels, the underlying inflammatory process, and individual host factors. The cumulative result is diminished blood flow, vascular alterations, and eventual occlusion with variable ischemia, necrosis, and tissue damage. An international revised nomenclature system provides the necessary nosology and findings relevant to classify each of the vasculitides. This article is an introduction and overview of the clinical presentation, differential diagnosis, laboratory evaluation, and treatment of systemic and nervous system vasculitides.

Pancreatic tumor in type 1 autoimmune pancreatitis: a diagnostic challenge

Background

The co-occurrence of type 1 autoimmune pancreatitis (AIP) and pancreatic tumor (PaT) has been previously reported. Pure AIP cases have favorable prognosis and are primarily treated with steroids, while AIP cases with PaT are associated with poor prognosis where the primary management is pancreatic resection. However, it’s a challenge to timely identify the concurrent PaT in AIP because of their similar clinical and radiological manifestations.

Methods

We retrospectively reviewed the data in two medical centers from January 2010 to April 2019. The inclusion criteria were as follows: 1) completion of abdominal CT imaging before invasive procedures to the pancreas, 2) a final diagnosis of type 1 AIP using the 2011 international consensus diagnostic criteria, 3) follow-up duration of at least one month unless AIP and PaT were identified simultaneously. The presence of PaT in AIP was made based on histopathological confirmation, and the absence of PaT in AIP was defined as no pathological or radiological evidence of concurrent PaT. Clinical and radiological characteristics including gender, age, surveillance period, serum IgG4 and Ca-199 levels, biopsy, extrapancreatic involvement, CT and MR (if performed) imaging characteristics were compared between AIP with and without PaT. The Fisher’s exact test was used for qualitative variables, and nonparametric Mann-Whitney test for quantitative variables. A p value ≤0.05 was considered statistically significant.

Results

A total of 74 patients with type 1 AIP were included, of which 5 (6.7%) had the concurrent PaT. The subtypes were pancreatic ductal adenocarcinoma (3/5), solitary extramedullary plasmacytoma in the pancreas (1/5) and cholangiocarcinoma in the pancreatic segment (1/5), respectively. Gender (p = 0.044), the pattern of pancreatic enlargement (p = 0.003), heterogeneity (p = 0.015), low-density (p = 0.004) on CT and rim enhancement on MRI (p = 0.050) differed significantly between AIP with and without PaT. None of the low-density characteristics on CT or other assessed MRI characteristics could significantly differentiate the two groups (p>0.05).

Conclusions

Female, focal pancreatic enlargement, pancreatic heterogeneity, low-density on CT and rim enhancement on MRI are suggestive of the concurrent PaT in type 1 AIP. The characteristics of low-density on CT or other MRI characteristics did not provide further diagnostic values.

[Clinical case of IgG4-related disease in a patient with Burkitt lymphoma]

The article provides a case of primary diagnosis of IgG4-related disease in a patient with Burkitt lymphoma.

A Series of Biopsy-proven Patients with Immunoglobulin G4-related Neurological Disease

Aim:

To study the clinical presentation, radiological findings, and therapy responsiveness of patients with biopsy-proven immunoglobulin G4 (IgG4)-related neurological disease.

Methods:

The study was conducted between January 2016 and March 2018 from the Department of Neurology and Pathology of Nizam's Institute of Medical Sciences. Patients with neurological symptoms and biopsy suggestive of IgG4-related disease (IgG4-RD) were included. These patients were studied for their demographic pattern and clinical presentation. The presence of serological markers such as vasculitic profile and IgG4 levels was analyzed. Radiological findings were studied in detail. Therapeutic agents used and the response to therapy were assessed.

Results:

There were six cases with IgG4-related neurological disease which were all hypertrophic pachymeningitis. The age ranged from 35 to 64 (mean = 46) years. The clinical presentation was acute in one, subacute in two, and chronic in three patients. The most common presenting symptom was headache (4), followed by gait and/or urinary disturbances (2), paraparesis (1), and diplopia (1). IgG4 levels were elevated in 50% of them. Pseudotumor-like mass and sinovenous thrombosis, not described previously, were seen in one patient. All the patients were treated with oral or intravenous steroid. Rituximab was given in three patients; azathioprine was the steroid-sparing agent in one patient. Those with acute/subacute onset of presentation had an excellent response to steroids. All the patients with a chronic duration of their symptoms received empirical anti-tuberculous therapy before a definitive diagnosis of Ig G4-RD was made.

Conclusions:

The characterization of patients with IgG4-related neurological disease based on the understanding of the clinical spectrum increases the confidence in the clinician to resort to early immunosuppression, thereby having prognostic implications.

Resection of lesions in the ileum of patients with IgG4-related disease may ameliorate disease progression without steroid administration

Background

IgG4-related disease (IgG4-RD) is a pathological condition that is characterized by an infiltrate composed of IgG4-positive plasma cells and recently recognized as an immune-mediated condition. It causes tissue throughout the body to become stiff and thickened due to autoimmune reactions that cause fibrosis and scarring. Disease-related changes commonly occur in the salivary glands, bile duct, pancreas, and lungs, but are seldom seen in the small bowel. A diagnosis of IgG4-RD is suspected if a high level of IgG4 is found on a blood test. The ideal diagnostic method is pathological examination, but because the clinical manifestations of IgG4-RD are very diverse and nonspecific, the disease may often go undiagnosed until an unrelated biopsy or resection specimen is obtained. The most common treatment for IgG4-RD is steroid use. However, tapering or stopping steroid administration is seen to result in recurrence in approximately 50% of cases. A complete cure is therefore considered extremely difficult.

Case presentation

A 69-year-old man with gastrointestinal obstruction underwent small bowel resection for two lesions. On histopathological examination, the specimen showed features of IgG4-RD. We performed several tests to detect other characteristics of IgG4-RD, but were unable to find any. The patient is being followed up regularly for a year and is being observed for any symptoms of recurrence.

Conclusions

We present a case of IgG4-RD wherein the ileum wall was significantly sclerosed, leading to gastrointestinal tract obstruction; therefore, we resected two sections of the ileum. We believe that resection of IgG4-RD lesions can help avoid long-term steroid use in patients, because the surgery completely eliminates the pathological origins of the condition.

Head and neck immunoglobulin G4 related disease: systematic review

BACKGROUND

Immunoglobulin G4 related disease is a recently described systemic syndrome. The head and neck region is the second most common site for presentation after the pancreas.

METHODS

PubMed and the Cochrane Library were searched from 1995 to July 2017 for all the studies on immunoglobulin G4 related disease diagnosed in the head and neck compartment. Patient-specific data were extracted and basic statistical analysis was performed.

RESULTS

Ninety-one patients were identified. Treatment was specified in 76 patients. Twenty patients received surgical treatment, eight of them in association with medical therapy. Fifty-six patients received medical treatment. The disease recurred in 25 per cent of patients treated with surgical treatment alone, in 3.6 per cent of patients treated with medical treatment alone and in 12.5 per cent of patients treated with both. All medical treatment protocols contained high-dose corticosteroids.

CONCLUSION

Early and correct diagnosis can avoid unnecessary surgical treatment, and glucocorticoid therapy can improve the long-term prognosis.

Predictive Factors for Autoimmune Pancreatitis Relapse After 3 Years of Maintenance Therapy

OBJECTIVES

Oral corticosteroid treatment is the standard therapy for autoimmune pancreatitis (AIP) and is highly effective. However, relapse may occur during maintenance therapy (MT). We aimed to clarify the predictive factors for relapse after 3 years of MT for use in deciding on the continuation of long-term MT.

METHODS

Among 56 retrospectively recruited AIP patients who received corticosteroid remission induction therapy followed by MT for a minimum of 5 years, 38 subjects were enrolled after exclusion criteria and divided into the relapse group of patients who experienced relapse after 3 years of MT and the nonrelapse group of patients who did not.

RESULTS

According to multivariate analysis, at least 4 other organ involvement numbers at diagnosis (hazard ratio, 5.82; 95% confidence interval, 1.203-28.192) and IgG of 1400 mg/dL or greater at 3 years of MT (hazard ratio, 4.41; 95% confidence interval, 1.096-17.790) were predictive factors for relapse after MT for 3 years, with patients exhibiting both predictive factors having a higher cumulative relapse rate than those with 1 or fewer predictive factor.

CONCLUSIONS

We uncovered 2 predictive factors for AIP relapse after 3 years of MT. These findings will assist in deciding corticosteroid therapy regimens at 3 years of MT to minimize AIP relapse risk and adverse corticosteroid effects.

Prediction and Management for Relapse of Type 1 Autoimmune Pancreatitis After Initial Steroid Treatment: A Long-Term Follow-up From China

OBJECTIVES

This study aimed to investigate the frequency, predictors, and management of relapse of type 1 autoimmune pancreatitis (AIP) after steroid treatment.

METHODS

One hundred one patients with type 1 AIP receiving steroid as initial treatment were enrolled. Predictors were identified by multivariate analysis using Cox proportional hazards model. Hazard ratios (HRs) and 95% confidence intervals (95% CIs) were calculated.

RESULTS

Thirty-nine (41.1%) patients experienced relapse after steroid treatment during a median follow-up of 40 months. The cumulative rate of relapse reached a plateau at 57.6% (95% CI, 50.3%-64.9%) at 59 months. Without maintenance therapy (HR, 4.53; 95% CI, 1.35-15.17) and proximal bile duct involvement (HR, 2.10; 95% CI, 1.07-4.14) were identified as risk factors. Repeated steroid treatment with the same initial dose but longer induction and tapering duration was given to 87.2% patients with relapse and obtained response (97.1%) during a short-term follow-up (median, 19 months).

CONCLUSIONS

Relapses are common in type 1 AIP after steroid treatment. Without maintenance therapy and proximal bile duct involvement were risk factors. Repeated steroid treatment with longer duration is effective for relapse.

A good response to steroid therapy in IgG4-related sclerosing cholangitis: a case report

IgG4-related sclerosing cholangitis is a rare autoimmune liver disease. Biliary tract imaging, serum IgG4 concentration, and histopathological examination are the major diagnostic criteria for IgG4-related sclerosing cholangitis. In this paper, we report a male patient with yellowish skin, in whom classical liver-protection drugs were initially given, but the efficacy was poor. After that, IgG4-related sclerosing cholangitis was diagnosed, and he achieved a good response to steroid therapy.

Autoimmune Pancreatitis

Over the course of the last 2 decades our knowledge of autoimmune pancreatitis has increased exponentially. In this review, we summarize the clinical presentation, diagnosis and treatment of AIP, to better allow general gastroenterologists and primary care providers to consider AIP as a as a rare but important cause of painless obstructive jaundice and recurrent acute pancreatitis. While steroids remain the mainstay of first line therapy, a number of patients with type 1 AIP require immunomodulators or rituximab to maintain remission; recommendations on the management of relapses continue to evolve.

Immunoglobulin G4-related disease of the thickened aortic valve extending to the left ventricular outflow tract causing severe aortic regurgitation and complete atrioventricular block: a case report

Background

Immunoglobulin G4-related disease (IgG4-RD) is a systemic disease characterized by the tumefactive lesions and infiltration of IgG4-positive plasma cells. IgG4-RD has been described in various organs, but rarely the aortic valve. There are only a few reports of aortic stenosis, and none on significant aortic regurgitation. In addition, previous case reports relating to aortic valve lesions led to surgery as a first-line treatment. The effect of steroid treatment has not yet been determined.

Case Summary

A 62-year-old man, receiving steroid therapy, who presented with general malaise, shortness of breath, and bradycardia. He had suspected IgG4-RD because of pancreatitis, lacrimal gland enlargement, and retroperitoneal fibrosis. An examination revealed a thickened aortic valve extending to the left ventricular outflow tract with severe aortic regurgitation and complete atrioventricular block. He received intensive steroid therapy for a suspected IgG4-related aortic valve lesion. The complete atrioventricular block improved, but worsening aortic regurgitation caused congestive heart failure. He required replacement of the aortic valve. A histopathological examination of the excised aortic valve leaflets revealed IgG4-positive lymphoplasmacytic infiltration with fibrotic tissue. The prosthetic valve was functioning well without leakage around the valve at the 1-year follow-up.

Discussion

This case highlights the rare possibility that IgG4-RD of the aortic valve also causes significant aortic regurgitation. Conservative treatment with steroids may induce regression of the lesion and contribute to the stability of the prosthetic valve after surgery, but it may also exacerbate heart failure due to the progression of aortic regurgitation in patients with aortic valve lesions.

Glucocorticoid receptor expression in resident and hematopoietic cells in IgG4-related disease

Immunoglobulin G4-related disease is a rare immune-mediated disease characterized by the infiltration of IgG4-positive plasma cells and unique storiform fibrosis of multiple organs. The majority of IgG4-related disease patients respond to glucocorticoids, yet the precise mechanism of their action remains unclear. Pathological sections of the submaxillary gland, kidney, and retroperitoneum from 20 patients in total diagnosed with IgG4-related disease were analyzed for glucocorticoid receptor expression and the cell types expressing glucocorticoid receptor. Strong and abundant expression of glucocorticoid receptor was observed in the submaxillary gland, kidney, and retroperitoneum of IgG4-related disease patients, while glucocorticoid receptor was rarely or only faintly observed in the submaxillary gland of patients with Sjögren's syndrome, radicular cysts and sialolithiasis or in the healthy kidney. Glucocorticoid receptor was mainly expressed in fibro/myofibroblasts, CD4-positive T cells and IgG4-positive plasma cells in the submandibular glands and kidneys of IgG4-related disease patients. The abundant expression of glucocorticoid receptor in various types of cells, including resident fibro/myofibroblasts in IgG4-related disease patients might provide clues to the mechanism of steroid responsiveness in IgG4-related disease patients.

IgG4-related Disease - A Systemic Disease that Deserves Attention Regardless of One's Subspecialty

IgG4-related disease (IgG4-RD) is an inflammatory condition characterized by a high serum IgG4 concentration and the abundant infiltration of lymphocytes and IgG4-positive plasma cells in the tissue, as well as spatial (diverse clinical manifestations) and temporal (the possibility of recurrence) multiplicities. Since the initial documentation of IgG4-related disease in patients with autoimmune pancreatitis in 2001, a growing body of evidence has been accumulating to suggest that various-virtually all-organs can be affected by IgG4-RD. In general, steroid therapy is effective and is considered to be the first-line treatment for IgG4-RD. The precise mechanism underlying this systemic disorder has remained unknown. Considering that IgG4-RD was specified as being an intractable disease in 2015, further studies are needed to clarify whether IgG4-RD is indeed a distinct disease entity or a complex of disorders of different etiologies and clinical conditions.

IgG4-related disease of pulmonary artery causing pulmonary hypertension

IgG4-related disease (IgG4-RD) is recognized as an immune-mediated condition with pathology features of lymphoplasmacytic infiltrate, storiform fibrosis, and obliterative phlebitis, accompanied with or without elevated serum IgG4 concentrations. However, few of pulmonary artery IgG4-RD causing pulmonary hypertension (PH) was reported.The medical records of 3 patients with pulmonary artery IgG4-RD inducing PH were analyzed retrospectively.Imaging findings demonstrated that the lesions of 3 patients located in pulmonary artery, which were initially diagnosed as pulmonary thrombus or malignant tumor. Computed tomography pulmonary angiography (CTPA), ultrasonic cardiogram, and positron emission tomography/computed tomography (PET/CT) didn't support the diagnosis of pulmonary thrombus or malignant tumor. Right heart catheterization (RHC) showed definite PH. Biopsy by right heart catheterization in 2 patients or pneumonectomy in 1 patient confirmed the diagnosis as IgG4-RD. Treated with glucocorticoids and cyclophosphamide or rituximab, 2 patients' IgG4 concentrations declined sharply and the lesions shrunk gradually. Another patient treated with glucocorticoids died of heart failure.IgG4-RD involved pulmonary artery causing PH was rare. A high index of awareness of this disease is required for early diagnosis and treatment. PET/CT might be a valuable approach to distinguish pulmonary artery IgG4-RD from pulmonary thrombus and malignant tumor.

Relative Rise of Serum IgG4 Levels After Steroid Therapy for Autoimmune Pancreatitis Predicts the Likelihood of Relapse

OBJECTIVES

Serum IgG4 level is a useful diagnostic marker of autoimmune pancreatitis (AIP); however, it is difficult to predict relapse. We investigated whether a change in serum IgG4 is predictive of AIP relapse during maintenance therapy.

METHODS

Seventy-three patients with AIP treated with steroids were divided into 3 groups according to their initial serum IgG4 levels: level 1 group (>2-fold upper limit), level 2 group (1- to 2-fold upper limit), and a normal group. The relapse rate and the prevalence of extrapancreatic lesions were compared between the 3 groups. The correlation between the relative rise of serum IgG4 levels and relapse during maintenance therapy was analyzed.

RESULTS

There were no differences in serum IgG4 levels in the presence or absence of relapse. The average number of extrapancreatic lesions was 1.02, 0.47, and 0.27 in level 1, level 2, and the normal group, respectively. The relative rise of serum IgG4 levels after steroid therapy was significantly higher in relapse than in nonrelapse cases. The area under the receiver operating characteristic curve of the relative rise of IgG4 levels for discriminating between the relapse and the nonrelapse cases was 0.85.

CONCLUSIONS

The relative rise of serum IgG4 levels after steroid therapy may provide an indication of relapse.

Combined membranous nephropathy and tubulointerstitial nephritis as a rare renal manifestation of IgG4-related disease: a case-based literature review

IgG4-related disease (IgG4-RD) is a newly recognized immune-mediated multisystemic disease characterized by a fibro-inflammatory condition with tissue infiltration of IgG4-positive plasma cells and often associated with elevated serum IgG4 levels. Typical renal involvement of IgG4-RD presents as tubulointerstitial nephritis (TIN), membranous or membranoproliferative nephropathy. We are presenting a case with combined IgG4 membranous nephropathy and TIN, as well as a literature review on pathophysiology, diagnosis and treatment of IgG4-RD. A 62-year-old man presented with weight loss and fatigue. Labs showed significant proteinuria and hematuria with elevated serum creatinine (2.5 mg/dL). CT/PET scan found scattered lymphadenopathy without increased FDG uptake. Kidney biopsy showed glomerular lesions as well as severe interstitial fibrosis and tubular atrophy. Immunohistochemistry study was negative for anti-phospholipase A2 receptor antibodies and showed interstitial lymphocytic infiltration with IgG4 positive plasma cells. Patient also had elevated serum IgG4 level and IgG4 to total IgG ratio. Prednisone treatment was initiated soon after the diagnosis was made, patient responded well with proteinuria and hematuria both resolved. IgG4-related disease (IgG4-RD) is a newly increasingly recognized immune-mediated multisystemic disease; IgG4-related membranous nephropathy should be included in the differential diagnosis for patients with proteinuria.

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

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

IgG4-related disease involving the esophagus: a clinicopathological study

Immunoglobulin G4 (IgG4)-related disease is a recently coined systemic disease characterized by specific histopathologic findings of an intense lymphoplasmacytic infiltrate, storiform fibrosis, and obliterative phlebitis in the presence of predominant IgG4-positive plasma cells. Although IgG4-related disease has been described in many organs, involvement of the esophagus is very rare. In this study, we describe the clinicopathologic characteristics of eight patients with IgG4-related esophagitis. We evaluated chronic esophagitis specimens with lymphoplasmacytic infiltrate obtained over the past 6 years (from January 2011 to February 2017) using a chart review, pathologic examination, and IgG4 immunohistochemical staining. The diagnoses of the specimens were either confirmed as IgG4-related esophagitis (IgG4-RE) or chronic esophagitis, not otherwise specified (CENOS), and the clinicopathologic data from each group were compared. Eight patients were diagnosed with IgG4-RE and 10 controls were identified and diagnosed with CENOS. In the IgG4-RE group, esophageal strictures were identified in three patients, two patients had postmyotomy treated achalasia, one patient had erosive esophagitis and another presented with an esophageal nodule. Only one patient had an unremarkable mucosa on endoscopy. In the CENOS group, four patients had esophageal strictures, six had erosive esophagitis, one patient had mild esophagitis. The IgG4-RE group had significantly higher numbers of IgG4-positive plasma cells (66.9 ± 21.9 vs. 4.7 ± 2.4 per high power field; P< 0.001) and a greater IgG4: IgG ratio 0.76 ± 0.13 vs. 0.06 ± 0.05; P< 0.001) when compared to CENOS patients. Two of the patients with recurrent esophageal strictures in the IgG4-RE group showed initial response to steroid therapy and are currently on immunosuppressive therapy which has significantly reduced the need for multiple esophageal dilatations. The presentation of IgG4-related esophageal disease can vary and the key to diagnosis is dependent on histopathology. These observations highlight the need for IgG4 immunohistochemical staining of esophageal biopsies especially in patients with mucosal ulceration, chronic inflammation, and plasmacytosis on biopsy. This will prevent unwarranted esophagectomies and failed medical treatment due to lack of recognition of this entity.

IgG4-related Hypophysitis with Subtle Hypopituitarism in an Elderly Diabetic Patient: Is Treatment or Observation Preferable?

A 70-year-old man with diabetes mellitus presented with an enlarged pituitary stalk in 2014. IgG4-related parotitis and submandibular sialoadenitis were diagnosed in 2012. He denied any symptoms related to a pituitary mass. His visual field was intact, and his hypopituitarism was subtle. The serum IgG4 level was elevated. A lip biopsy revealed strong fibrosis and hyper-infiltration of IgG4-positive plasma cells. Based on these findings, IgG4-related hypophysitis was diagnosed. The patient was carefully followed without specific intervention. His clinical condition showed no change until December 2016, suggesting a stable, natural course. Care should be taken when considering glucocorticoid therapy, especially for elderly diabetic patients, given possible side effects.

Low-dose maintenance steroid treatment could reduce the relapse rate in patients with type 1 autoimmune pancreatitis: a long-term Japanese multicenter analysis of 510 patients

BACKGROUND

The effect of maintenance steroid treatment (MST) in reducing the risk of relapse in patients with autoimmune pancreatitis (AIP) remains under debate. The aim of this study was to validate the effect of MST on AIP administered in accordance with the 2010 Japanese consensus guidelines.

METHODS

The clinical data of patients with (n = 510) from 22 high-volume centers in Japan were studied. The primary endpoints were the relapse rates (RRs) in patients administered MST versus those not administered MST. The secondary endpoints were the optimal dose and duration of MST in terms of steroid toxicity and the predictors of relapse.

RESULTS

The RRs were 10.0% within 1 year, 25.8% within 3 years and 35.1% within 5 years. The RR in the steroid therapy group reached a plateau at 42.7% at 7 years. In terms of the optimal dosage, the overall RR in the MST 5 mg/day group was 26.1%, which was significantly lower than that in the group which had discontinued steroid therapy (45.2%; p = 0.023) or was receiving MST at 2.5 mg/day (43.4%, p = 0.001). The RRs in the group receiving MST at ≥5 mg/day versus the patient group receiving MST at <5 mg/day were 10.6 vs. 10.3% within 1 year, 23.5 vs. 32.9% within 3 years and 32.2 vs. 41.3% within 5 years, respectively (log-rank, p = 0.028). The best cutoff value of the total steroid dose for serious steroid toxicity was 6405 mg, with a moderate accuracy of 0.717 determined using the area under the curve. Presence of diffuse pancreatic swelling [odds ratio OR) 1.745; p = 0.008) and MST at >5 mg/day were identified as predictors of relapse (OR 0.483; p = 0.001).

CONCLUSIONS

The RR could continue to increase for 7 years even under MST. Based on our analysis of the side effects of steroid therapy, MST at 5 mg/day for 2 (total 4625 mg) to 3 (total 6425 mg) years might be a rational and safe therapeutic strategy in terms of keeping the RR to <30% while avoiding potential steroid toxicity.