International Consensus Guidance Statement on the Management and Treatment of IgG4-Related Disease

IgG4-related disease: association between chronic rhino-sinusitis and systemic symptoms

PURPOSE

The objective of this study is to analyze the relationship between chronic rhino-sinusitis (CRS) and systemic symptoms in patients with IgG4-related disease (IgG4-RD).

PATIENTS AND METHODS

The patients with IgG4-RD, confirmed by restrict association with clinical and histopathological manifestations between March 2013 and July 2016, were enrolled and followed-up for 1 year at the Tongren Hospital, Capital Medical University. The patients were divided into two groups: the case group included IgG4-RD patients with CRS confirmed by clinical and imaging, while the control group included IgG4-RD patients without CRS confirmed by clinical and imaging. Age, gender, clinical manifestations, the percentage of eosinophils in peripheral blood, sedimentation (ESR), C-reaction protein, serum IgE and IgG4 levels, histopathology, and treatment drugs at the baseline and 1 year of follow-up were compared between the two groups.

RESULTS

A total of 46 cases met the diagnostic criteria for IgG4-RD. A total of 30 patients (65.2%) had IgG4-RD complicated with CRS, and were aged 49.7 ± 13.4 years, with male:female ratio = 2:1. The disease duration in the case group was longer than that in the control group (3.0 versus 0.8, p = 0.009). The ratio of ocular involvement was higher (86.7 versus 60%, p < 0.001), and allergic manifestations including drug allergy, asthma, and allergic skin were more common (56.5 versus 20%, p = 0.004), with a higher percentage of eosinophils in peripheral blood (8.5 versus 3.3%, p = 0.018) and more sensitive to glucocorticoids (6.0 versus 3.5, p = 0.004) than those in the control group.

CONCLUSIONS

CRS in patients with IgG4-RD was closely associated with IgG4-related ocular lesions, which was more prone to allergic manifestations accompanied by raised percentage of eosinophils in peripheral blood. The treatment of patients with IgG4-RD complicated with CRS was more effective than those with IgG4-RD without CRS.

The Clinicopathologic Spectrum of IgG4-Related Disease

Immunoglobulin G4-related disease is a fibroinflammatory systemic disease that is characterized by focal or diffuse organ infiltration by immunoglobulin G4-bearing plasma cells. Immunoglobulin G4-related disease may affect any organ, and a high index of suspicion is necessary for early detection to avoid irreversible fibrosis, organ dysfunction, and death. Tumor-forming lesions are common radiological features of immunoglobulin G4-related disease that need to be differentiated from malignancies. The diagnostic approach requires the integration of clinical, biochemical, and radiographic manifestations with classic histopathologic features, which remain crucial to diagnosis. The histology of immunoglobulin G4-related disease is determined by a dense lymphoplasmacytic infiltrate, storiform fibrosis, and obliterative phlebitis in the presence of increased immunoglobulin G4-positve plasma cells. Although immunoglobulin G4-related disease forms a distinct, clinically independent disease category, many questions and problems remain unanswered, especially on its pathogenesis and the role of immunoglobulin G4. Advances in the understanding of immunoglobulin G4-related disease are likely to change the diagnostic approach in the future and create potential targets for therapeutic purposes. Here we describe the concept of immunoglobulin G4-related disease and the most recent knowledge in the clinico-pathological characteristics on this emerging disease. This study can guide clinicians in early diagnosis and prevent unnecessary surgical resections.

The shaping, making and baking of a pancreatologist

The European Pancreatic Club Lifetime Achievement award is a distinction awarded for research on the pancreas. It comes with the obligation to submit a review article to the society's journal, Pancreatology. Since the research topics of my group have recently been covered in reviews and book chapters I want to use this opportunity to appraise the stations of my clinical and research education, the projects that I pursued and abandoned, the lessons I have learned from them, and the women and men who influenced my training and development as a physician scientist. Some crossed my path, some become collaborators and friends, and some turned into role models and had a lasting impact on my life.

IgG4-related pulmonary disease: the protean impersonator?

IgG4-related disease is an immune-mediated fibro-inflammatory disease, characterised by distinct pathological features. An increasing number of clinical phenotypes are described, from single-organ disease to a multisystem disorder, which can present to a variety of different specialities. Recognition is key; its protean manifestations can mimic other inflammatory diseases, infection and malignancy. Here, we present three cases to highlight the importance of being familiar with this condition in its various forms.

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 retroperitoneal fibrosis overlapping with primary biliary cirrhosis and primary Sjögren's syndrome: A case report

RATIONALE

IgG4-related disease (IgG4-RD) is a chronic fibro-inflammatory disorder which is characterized by elevated levels of serum IgG4 and infiltration of IgG4-bearing plasma cells in the involved organs. Primary biliary cirrhosis (PBC) and Primary Sjögren's syndrome (pSS) are both distinct from IgG4-related disease. We herein describe a Chinese patient with IgG4-related RPF overlapping with PBC and pSS.

PATIENT CONCERNS

We report a case of 69-year-old male with recurrent lower abdominal pain for 10 months. Laboratory data showed elevated erythrocyte sedimentation rate and hepatobiliary enzymes, renal dysfunction, high titers of antinuclear antibody, anti-SS-A antibody and anti-mitochondrial type 2, high immunoglobulin (Ig) G levels and elevated serum IgG4 (9 g/L). Contrast-enhanced computed tomography and magnetic resonance imaging were suggestive of retroperitoneal fibrosis and unilateral ureteral occlusion. Immunohistochemical staining for IgG4 did not demonstrate infiltration of IgG4-positive plasma cells in the retroperitoneal mass, but revealed significant infiltration of lymphocytoplasma cells as well as fibrosis and fibrin accumulation.

DIAGNOSES

The patient was diagnosed with IgG4-related retroperitoneal fibrosis based on the International Consensus Diagnostic Criteria. He was also diagnosed with primary biliary cirrhosis and primary Sjögren's syndrome.

INTERVENTIONS

250 mg ursodeoxycholic acid was administered twice daily, and prednisolone was initiated at a dose of 40 mg/day and then tapered to 25 mg after 45 days.

OUTCOMES

The size of the retroperitoneal soft tissue mass gradually reduced and the abnormal laboratory parameters were restored to normal.

LESSONS

This rare clinical condition has seldom been reported in the literature, which suggests that common immunogenetic factors may be involved in the development of IgG-related RPF, PBC and pSS.

IgG4-related orbital disease

CASE REPORT

The case is presented of a 64-year-old woman with bilateral palpebral swelling and dacryoadenitis, exophthalmos, and a history of chronic rhinitis and asthma. An increase in serum IgG4 was observed, and an incisional biopsy of lacrimal glands was performed, which showed fibrosis and a lymphoplasmacytic infiltrate with IgG4 producing cells.

DISCUSSION

Orbital involvement in IgG4-related disease is frequent. Bilateral dacryoadenitis is the most common manifestation. Histopathology is essential for the diagnosis and to exclude malignancy.

Immunoglobulin G4 sinusitis in association with aspirin-exacerbated respiratory disease

BACKGROUND

Immunoglobulin G4 (IgG4) related disease is a systemic inflammatory disease characterized by tumor-like tissue infiltration with IgG4 positive (IgG4+) plasma cells. Aspirin-exacerbated respiratory disease (AERD) is defined as asthma, chronic rhinosinusitis with nasal polyposis, and hypersensitivity to cyclooxygenase-1 inhibitors.

OBJECTIVE

We described a case of a non-smoking 61-year-old male with prior NSAID sensitivity who presented with a 1-year history of left eye proptosis associated with chronic nasal symptoms, ultimately identified as concurrent AERD and IgG4 sinusitis.

METHODS

The patient was evaluated in the clinic and diagnosed by using clinical, radiographic, and surgical biopsy findings.

RESULTS

Although initial concern was greatest for malignancy, a biopsy specimen confirmed the presence of a dense lymphoplasmacytic infiltrate and storiform fibrosis, associated with increased IgG4+ plasma cells. Therefore, IgG4-related disease (RD) was identified in this patient with AERD.

CONCLUSION

Shared type II inflammation may be responsible for the coexistence of IgG4-RD and AERD as observed in our patient. Health care workers must be cognizant of the simultaneous presentation of both IgG4-RD and AERD.

Immunoglobulin G4-related disease of the paranasal sinuses

Immunoglobulin G4-related disease (IgG4-RD) is becoming increasingly documented. It was first described in relation to autoimmune pancreatitis. Features of the disease include tissue infiltration by IgG4 plasma cells with associated fibrosis and the growth of pseudotumours. A 71-year-old woman presented with increasing right cheek swelling and mild proptosis. Ten years earlier, she had a similar presentation and was diagnosed with an inflammatory pseudotumour. Examination revealed a lesion in the right nasal cavity. CT and MRI confirmed a mass within the right maxillary antrum extending into the nasal cavity. Endoscopic biopsies showed florid plasma cell infiltrate with marked increase in IgG+ plasma cells. Immunostaining expressed IgG4 (70%). She was started on a course of prednisolone and her symptoms resolved. IgG4-RD is becoming an emerging disease entity. Its involvement in the paranasal sinuses can mimic nasal tumours. Major surgical resection should be avoided as patients can often be treated medically.

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.

Imaging appearance of fibrosing diseases of the retroperitoneum: can a definitive diagnosis be made?

PURPOSE

To assess the frequency with which previously reported characteristic findings of retroperitoneal fibrosis (RPF) (a circumferential or almost circumferential peri-aortic mass centered at L4, which does not displace the abdominal aorta or proximal common iliac arteries) are present in patients with RPF, in patients with other fibrosing diseases, and in cancer patients referred to a subspecialty clinic with a suspected diagnosis of RPF, in order to determine whether diagnostic percutaneous biopsy can be avoided in some patients.

METHODS

This HIPAA-compliant Institutional Review Board-approved retrospective study assessed clinical and CT and MR imaging abnormalities on imaging studies in 92 patients referred to a subspecialty clinic with suspected RPF over a 14-year period. Two reviewers, in consensus, determined the frequency of different CT and MRI findings in three groups of patients (Group 1: those with an eventual diagnosis of RPF, Group 2: those with a fibrosing disease associated with vascular or urologic abnormalities, and Group 3: those with cancer). Assessed imaging features included the presence of retroperitoneal masses, whether masses were single or multiple, whether such masses were circumferential or nearly circumferential, whether they displaced the aorta away from the spine (with the degree of such displacement measured), and whether there were abnormalities outside of the peri-aortic region of the retroperitoneum. The frequency with which findings previously reported as characteristic of RPF were present was determined for each of the three groups. Imaging results were correlated with the final diagnoses.

RESULTS

Of 68 subjects eventually diagnosed with retroperitoneal fibrosis (RPF) (Group 1), 47 had peri-aortic retroperitoneal masses, 18 of which displaced the aorta anteriorly away from the spine. Of 12 subjects with fibrosing abnormalities related to vascular or urologic disease (Group 2), six had retroperitoneal masses, none of which displaced the aorta away from the spine. Of 12 subjects with malignancies (Group 3), six had peri-aortic retroperitoneal masses only two of whom had aortic displacement. Only 34 of 68 Group 1 subjects had peri-aortic masses characteristic of RPF, compared with six Group 2 subjects and one Group 3 subject. Subjects with characteristic retroperitoneal masses were significantly more likely to have benign disease than cancer (p = 0.009).

CONCLUSION

Many patients with RPF do not have characteristic imaging findings. Contrary to prior publications, absence of aortic displacement is not seen in all patients with RPF and is seen in some cancer patients. Nonetheless, when infiltrative peri-aortic retroperitoneal soft tissue that does not displace the aorta is encountered on CT or MRI, RPF can be diagnosed with a high degree of confidence, obviating the need for biopsy.

IgG4-related kidney disease: the effects of a Rituximab-based immunosuppressive therapy

IgG4-related disease (IgG4-RD) is a recently recognized disorder, characterized by elevated serum IgG4 concentrations, dense tissue infiltration of IgG4-positive plasma cells and storiform fibrosis. Treatment is usually based on steroids, however, relapses and long-term adverse effects are frequent. We prospectively studied 5 consecutive patients with histologically-proven IgG4-RD and renal involvement, treated with an extended Rituximab protocol combined with steroids. Two doses of intravenous cyclophosphamide were added in 4 patients. Five patients with IgG-RD were investigated: three had tubulointerstitial nephritis (TIN), while two had retroperitoneal fibrosis (RPF). In the patients with TIN, renal biospy was repeated after 1 year. In the patients with TIN, estimated glomerular filtration rate (eGFR) at 12 months increased from 9 to 24 ml/min per 1.73 m²; IgG/IgG4 decreased from 3,236/665 to 706/51 mg/dl; C3/C4 increased from 49/6 to 99/27 mg/dl; CD20⁺ B-cells decreased from 8.7% to 0.5%; Regulatory T-cells decreased from 7.2% to 2.5%. These functional and immunologic changes persisted at 24 months and in two patients at 36 months. A repeat renal biopsy in the patients with TIN showed a dramatic decrease in interstitial plasma cell infiltrate with normalization of IgG4/IgG positive plasma cells. The patients with RPF showed a huge regression of retroperitoneal tissue. In this sample of patients with aggressive IgG4-RD and renal involvement, treatment aimed at depleting B cells and decreasing antibody and cytokine production was associated with a substantial, persistent increase in eGFR, and a definite improvement in immunologic, radiologic and histological parameters.

Failure of remission induction by glucocorticoids alone or in combination with immunosuppressive agents in IgG4-related disease: a prospective study of 215 patients

Background

The aim of this study was to assess the outcomes of remission induction in patients with IgG4-related disease (IgG4-RD) in our cohort, and to investigate the characteristics, prognosis, and risk factors in the patients failed of remission induction.

Methods

We prospectively enrolled 215 newly diagnosed patients with IgG4-RD, who were initially treated with glucocorticoid (GC) alone or in combination with immunosuppressive agents (IM), and had at least 6 months of follow up. The therapeutic goals of remission induction were defined as fulfilling each of the following after the 6-month remission induction stage: (1) ≥ 50% decline in the IgG4-RD responder index (RI); (2) GC tapered to maintenance dose; and (3) no relapse during GC tapering. The patients not achieving the therapeutic goals were considered to have failed of remission induction.

Results

There were 26 patients in our cohort who failed of remission induction, including 16 (20.8%) on GC monotherapy, and 10 (7.2%) on combination therapy comprising GC and IM. The lacrimal gland and lung were most common sites of remission induction failure. Among the patients who relapsed during remission induction stage, 52.9% had secondary relapse during follow-up. Eosinophilia, higher baseline RI, more than five organs involved and dacryoadenitis were risk factors for remission induction failure with GC monotherapy, and the incidence of remission induction failure was 71.4% in the patients with more than three risk factors. After 6-month treatment, the patients who failed of remission induction had significantly higher erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and IgG4.

Conclusion

In our cohort, 20.8% of patients failed of remission induction with GC monotherapy, while 7.2% of patients failed of remission induction with combination therapy comprising GC and IM.

Electronic supplementary material

The online version of this article (10.1186/s13075-018-1567-2) contains supplementary material, which is available to authorized users.

Salivary Gland Pathology in IgG4-Related Disease: A Comprehensive Review

IgG4-related disease (IgG4-RD) is a rare fibroinflammatory condition that can affect almost any organ, characterized by swollen lesions and often by eosinophilia and elevated serum IgG4 concentrations. The diagnosis of IgG4-RD is a challenging task: in fact, single or multiple organs can be affected and clinical, serological, and histological findings can be heterogeneous. In IgG4-RD, the involvement of salivary glands is observed in 27% to 53% of patients. Several organ-specific conditions, now recognized as different manifestations of IgG4-related sialadenitis (IgG4-RS), were viewed in the past as individual disease entities. The study of salivary glands may sometimes be complex, because of the number of pathological conditions that may affect them, often with overlapping clinical pictures. Integration of different imaging techniques is often required in the case of swelling of salivary glands, even though biopsy remains the gold standard for a definite diagnosis of IgG4-RS. Thus, in this review, we discuss new insights in the pathogenesis of IgG4-RD, focusing on its clinical aspects and the tools that are currently available for a correct differential diagnosis when the salivary glands are involved.

IgG4-related Disease in the Stomach which Was Confused with Gastrointestinal Stromal Tumor (GIST): Two Case Reports and Review of the Literature

Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated fibro-inflammatory disorder characterized by specific pathological findings and elevated serum IgG4 level. IgG4-RD in the stomach is rare, and occasionally diagnosed as gastric subepithelial tumor (SET) by endoscopy or computed tomography scan. Two female patients in the age group of 40–50 years were diagnosed with 4 cm sized gastric SET. One underwent laparoscopic gastric wedge resection. Another one had a history of subtotal gastrectomy for early gastric cancer and idiopathic thrombocytopenic purpura with oral steroids administration. She underwent a completion total gastrectomy with splenectomy for the gastric SET and ITP. The pathology showed storiform fibrosis, and IgG4 was positive in immunohistochemistry (IHC) stain. IgG4-RD is known as a medical disease that could be treated with oral steroids. The difficulty in preoperative diagnosis of the disease occasionally causes unnecessary gastric resection. Thus, preoperative diagnostic methods for IgG4-RD such as deep biopsy with IHC stain or magnetic resonance imaging are needed.

Inferior vena cava thrombosis as the initial presentation of IgG4-related retroperitoneal fibrosis: Case report and literature review

IgG4-related disease is an immune-mediated deposition of fibro-inflammatory tissue with IgG4-positive plasma cells and dense fibrosis in a single or multiple organs. It often raises concern for malignancy requiring biopsy for diagnosis. Presentation may vary according to organ involved. IgG4-related retroperitoneal fibrosis accounts for two-thirds of the previously considered idiopathic retroperitoneal fibrosis cases. In IgG4-related retroperitoneal fibrosis, computed tomography scan or magnetic resonance imaging shows periaortic soft tissue that extends from below the kidneys to iliac arteries and entrap ureters causing hydronephrosis and renal failure. We present a rare case of IgG4-related retroperitoneal fibrosis presenting with leg swelling and pain due to inferior vena cava compression and thrombosis, and we review current concepts on disease pathogenesis, diagnosis and treatment.

Suspected Frequent Relapsing IgG4-related Lung Disease in Kidney Transplant Patient: A Case Report

Besides the initial description of IgG4-related pancreatic disease, other sites are now commonly involved. However, occurrence of IgG4-related disease is rare in organ transplanted patients. A 57-year-old man who received a kidney transplantation presented with recurrent dyspnea on exertion. A computed tomography scan of the chest revealed bilateral interlobular septal thickening and multiple tubular and branching small nodular lesions in the right upper lobe, and mass-like consolidation of the left middle lobe. Despite no elevation of serum IgG4 level, a percutaneous core needle biopsy on consolidative mass showed interstitial fibrosis and infiltration of IgG4-positive plasma cells to be more than > 20 per high power field. After treatment with glucocorticoids and rituximab, the consolidative mass of the left middle lobe disappeared.

Clinical Utility of FDG PET/CT in Patients with Autoimmune Pancreatitis: a Case-Control Study

Autoimmune pancreatitis (AIP) shares overlapping clinical features with pancreatic cancer (PC). Importantly, treatment of the two conditions is different. We investigated the clinical usefulness of ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in patients with suspected AIP before treatment. From September 2008 to July 2016, 53 patients with suspected AIP at National Taiwan University Hospital had PET/CT prior to therapy to exclude malignancy and evaluate the extent of inflammation. Their scans were compared with those from 61 PC patients. PET imaging features were analyzed using logistic regression. Significant differences in pancreatic tumor uptake morphology, maximum standardized uptake value, high-order primary tumor texture feature (i.e. high-gray level zone emphasis value), and numbers and location of extrapancreatic foci were found between AIP and PC. Using the prediction model, the area under curve of receiver-operator curve was 0.95 (P < 0.0001) with sensitivity, specificity, positive predictive, and negative predictive values of 90.6%, 84.0%, 87.9%, and 87.5% respectively, in differentiating AIP from PC. FDG PET/CT offers high sensitivity, albeit slightly lower specificity in differentiating AIP from PC. Nonetheless, additional systemic inflammatory foci detected by the whole body PET/CT help confirm diagnosis of AIP in these patients before initiating steroid therapy, especially when biopsy is inconclusive.

Stage classification of IgG4-related dacryoadenitis and sialadenitis by the serum cytokine environment

OBJECTIVES

Patients with immunoglobulin-G4 related disease (IgG4-RD) diagnosed according to the comprehensive diagnostic criteria (CDC) show varied therapeutic responses and prognoses. We assumed that there are clinical stages in IgG4-RD and have verified it using serum cytokine levels in the groups classified by lesion distribution.

METHODS

Definite IgG4-related dacryoadenitis and sialadenitis (IgG4-DS) cases were divided according to the CDC for IgG4-RD into 11 cases with focal type and 30 cases with systemic type. The levels of serum interleukin (IL)-4, IL-5, IL-6, IL-10, IL-13, IL-15, IL-21, interferon (IFN)-α, IFN-γ, tumor necrosis factor (TNF)-α, transforming growth factor (TGF)-β1, and monocyte chemotactic protein (MCP)-1 were measured in healthy controls, allergic patients, probable IgG4-RD cases, and focal and systemic type cases. The cytokine environment was analyzed in each group. The 52 definite IgG4-RD cases were next classified into four groups with cluster analysis in terms of therapeutic responses and prognosis. The relationships between each cytokine level and therapeutic responses were also analyzed.

RESULTS

Both serum IL-5 and IFN-α concentrations were very low in healthy controls, but they increased in the allergic cases, probable cases, and focal and systemic type cases. The level of serum IL-5 was significantly higher in definite cases than in healthy controls. The serum IL-5 level was also significantly increased in the groups with a poor prognosis than in the good prognosis group.

CONCLUSION

These results suggest that there are clinical stages in IgG4-RD, and serum IL-5 play roles in the pathogenesis of IgG4-RD.

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.

Treatment of immunoglobulin G4-related sialadenitis: outcomes of glucocorticoid therapy combined with steroid-sparing agents

Background

Immunoglobulin G4-related sialadenitis (IgG4-RS) is a newly recognized immune-mediated systemic disease. Despite its good response to steroid therapy, its treatment protocol is not standardized and the long-term outcome is controversial. The study was conducted to determine the short-term and long-term outcomes of IgG4-RS patients treated with glucocorticoids and steroid-sparing immunosuppressive agents, to analyze secretory function, serological and radiological changes in salivary glands and to assess the usefulness of serum IgG4 level as an indicator of disease activity.

Methods

IgG4-RS patients who were treated for more than 3 months were enrolled. Serological tests, salivary gland function assessment and computed tomography (CT) were performed before treatment and during follow up. The treatment outcomes in the short and the long term were evaluated, and the relationship between serum IgG4 level and salivary gland volume was analyzed.

Results

Glucocorticoids were used in all 43 patients and steroid-sparing immunosuppressive agents in 38 patients (88.4%). The follow-up period was 24.6 ± 14.9 months. Clinical remission was achieved in all patients after induction therapy. During short-term observation, salivary gland secretion significantly increased, and the serum IgG4 levels, the volumes and CT values of submandibular and parotid gland decreased significantly (P < 0.001). For long term, relapse occurred in 32.5% patients within 55 months in the regularly treated group, while all seven irregularly treated patients relapsed. However, the relapse-free survival curves were not significantly different between the steroid monotherapy and the combination therapy groups (P = 0.566). Submandibular glands, lacrimal glands, sublingual glands, nasal and paranasal cavity were commonly relapsing organs. In clinically stable patients, a serologically unstable condition occurred in 54.9% patients within 55 months and medication adjustment was performed accordingly. Volume changes in the submandibular and parotid glands were associated with serum IgG4 levels and time of follow up (R²_adjusted = 0.905, P < 0.0001 and R²_adjusted = 0.9334, P < 0.0001, respectively).

Conclusions

The combination of glucocorticoid and steroid-sparing agents could be effective for treating IgG4-RS, and restoring salivary gland function. Serum IgG4 levels could predict disease activity.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-017-1507-6) contains supplementary material, which is available to authorized users.

Immunoglobulin G4-related dacyroadenitis presenting as bilateral chorioretinal folds from severely enlarged lacrimal glands

Purpose

To describe a case of immunoglobulin G4 (IgG4)-related dacyroadenitis presenting as bilateral chorioretinal folds from eyeball compression by massively enlarged lacrimal glands.

Observations

A 51-year-old woman with severely enlarged bilateral lacrimal glands was diagnosed as having IgG4-related dacryoadenitis. The glands strongly compressed the globes, forming chorioretinal folds resembling those found in orbital malignancy. Eventual treatment with oral prednisolone dramatically reduced the volume of the lacrimal glands and released globe compression on magnetic resonance imaging. However, the chorioretinal folds remained in the right fundus and symptoms of blurred vision improved but persisted.

Conclusions and importance

This is the first account of chorioretinal fold formation by severely enlarged lacrimal glands appearing in IgG4-related dacryoadenitis. Chorioretinal fold formation by an enlarged lacrimal gland occurring bilaterally may represent a basis for suspecting IgG4-related dacryoadenitis. Prompt treatment is recommended for patients presenting with very large lacrimal glands to avoid visual impairment.

Immunoglobulin G4-related kidney diseases: An updated review

This review will encompass definition, pathogenesis, renal clinical manifestations and treatment of immunoglobulin G4-related diseases (IgG4-RDs). IgG4-RD is a recently recognized clinical entity that often involves multiple organs and is characterized by high levels of serum immunoglobulins G4, dense infiltration of IgG4+ cells and storiform fibrosis. Cellular immunity, particularly T-cell mediated immunity, has been implicated in the pathogenesis of IgG4-RDs. The most frequent renal manifestations of IgG4-RD are IgG4-related tubulointerstitial nephritis, membranous glomerulopathy and obstructive nephropathy secondary to urinary tract obstruction due to IgG4-related retroperitoneal fibrosis. IgG4-RD diagnosis should be based on specific histopathological findings, confirmed by tissue immunostaining, typical radiological findings and an appropriate clinical context. The first line treatment is the steroids with two warnings: Steroid resistance and relapse after discontinuation. In the case of steroid resistance, B cell depleting agents as rituximab represent the second-line treatment. In the case of relapse after discontinuation, steroid treatment may be associated with steroid sparing agents. Since the disease has been only recently identified, more prospective, long-term studies are needed to an improved understanding and a more correct and safe treatment.

A case of IgG4oligoarthritis mimicking psoriatic arthritis

IgG₄-related disease (IgG₄-RD) is a rare but rapidly emerging immune-mediated fibroinflammatory condition that can affect almost any organ. It is typically associated with involvement of organs such as lymph nodes, submandibular glands, orbits, periaortic region and pancreas. However, IgG₄-RD presenting primarily as an inflammatory arthritis is much less recognised. We present a rare case of IgG₄-RD mimicking psoriatic arthritis. In spite of normal circulating IgG₄ plasma levels, a clinical index of suspicion was required to obtain a histopathological diagnosis. The patient's aggressive arthritis disease did not initially respond to typical disease- modifying agents such as methotrexate. Instead, we report a dramatic response to B cell depletion with rituximab. It is important to emphasise this case as a rare presentation of a rare disease. IgG₄-RD is a rapidly emerging condition and the diagnosis should be considered when the alternatives do not seem to fit.

Current perspectives on autoimmune pancreatitis and IgG4-related disease

IgG4-related disease (IgG4-RD) is a fibroinflammatory disorder recognized as a novel clinical entity with either synchronous or metachronous multi-organ involvement. Patients with IgG4-RD show diffuse or focal organ enlargement and mass-forming or nodular/thickened lesions with abundant infiltration of IgG4-positive plasmacytes and fibrosis, and such patients respond well to steroid treatment. It should be differentiated from mimics by a combination of serum IgG4 level, imaging features, and histopathological findings. The current first-line drug is corticosteroids, or rituximab in high-risk patients for steroid intolerance. Although relapse rates are high, standardized protocols for relapsed cases have not been approved yet. Based on genetic factors, disease-specific or -related antigens, abnormal innate and adaptive immunity may be involved, although the precise pathogenic mechanism and long-term outcome still remain unclear.

Immunoglobulin G4-related ophthalmic disease

Immunoglobulin G4-related disease (IgG4-RD) is a recently recognized inflammatory disease of unknown etiology. It characterized by distinctive histopathological appearance of dense IgG4-positive lymphoplasmacytic infiltrates, storiform fibrosis, and obliterative phlebitis in one or more organs, simultaneously or subsequently. In cases of ocular adnexal involvement, unique clinicohistopathological features were delineated by recent studies, and IgG4-related ophthalmic disease (IgG4-ROD) is generally recognized as the disease name. A significant proportion of previous labeled idiopathic orbital inflammations and Mikulicz's disease are now consistent with a diagnosis of IgG4-ROD. Increasing studies have accumulated regarding its epidemiology, diagnosis, clinical features, treatment, and the association between lymphoma. In this review, we summarize our present understanding of IgG4-ROD.

Thoracic Paravertebral Mass as an Infrequent Manifestation of IgG4-Related Disease

Case

A 50-year-old African American male presented with abdominal pain and significant weight loss. On physical examination, he had parotid and submandibular gland enlargement associated with right eye proptosis. Computed tomography showed a thoracic paravertebral soft tissue mass, enlarged lymph nodes, and ascending aortic aneurysm. Laboratory results were remarkable for elevated total IgG and IgG4 subclass. The submandibular gland pathology revealed chronic sclerosing sialadenitis, with a large subset of inflammatory cells positively staining for IgG4. The histology of the paravertebral mass demonstrated fibrosclerosis with increased lymphocytic infiltrate, associated with increased IgG4 plasma cells. He was diagnosed with immunoglobulin G4-related disease (IgG4-RD). Steroid therapy initially yielded improvement; however, after steroids were stopped, there was disease recurrence. Prednisone was restarted, and the plan was to start him on rituximab. Interestingly, the patient's brother also had IgG4-RD.

Conclusion

IgG4-RD can present as a paravertebral mass which is usually responsive to steroids; however, recurrent and resistant disease can be seen for which steroid-sparing agents such as rituximab should be considered. In addition, to the best of our knowledge, this is the first reported case of IgG4-RD in two family members presenting as a paravertebral mass, highlighting an exciting area for more research in the future.

Current approach to the diagnosis of IgG4-related disease - Combination of comprehensive diagnostic and organ-specific criteria

IgG4-related disease (IgG4-RD) is a fascinating clinical entity proposed by Japanese investigators, and includes a wide variety of diseases, formerly diagnosed as Mikulicz's disease (MD), autoimmune pancreatitis (AIP), interstitial nephritis, prostatitis, retroperitoneal fibrosis, etc. Although all clinicians in every field of medicine may encounter this new disease, a unifying diagnostic criterion has not been established. In 2011, the Japanese IgG4 team, organized by the Ministry of Health, Labor and Welfare (MHLW) of Japan, published comprehensive diagnostic criteria for IgG4-RD. Several problems with these criteria have arisen in clinical practice, however, including the difficulty obtaining biopsy samples from some patients, and the sensitivity and the specificity of techniques used to measure serum IgG4 concentrations. Although serum IgG4 concentration is an important clinical marker for IgG4-RD, its diagnostic utility in differentiating IgG4-RD from other diseases, called IgG4-RD mimickers, remains unclear. This review describes the current optimal approach for the diagnosis of IgG4-RD, based on both comprehensive and organ-specific diagnostic criteria, in patients with diseases such as IgG4-related pancreatitis (AIP), sclerosing cholangitis, and renal, lung and orbital diseases.

Myasthenia gravis with antibodies to MuSK: an update

Myasthenia gravis with antibodies to the muscle-specific tyrosine kinase (MuSK⁺ MG) is a rare disease with distinctive pathogenic mechanisms and clinical features. An acute onset and predominant bulbar muscle weakness are very common and highly suggestive of the disease. On the other hand, a more indolent course, atypical ocular presentation, and signs of cholinergic hyperactivity may complicate the diagnosis. Though MuSK⁺ MG is still a severe disease, over the years we have observed a steady reduction in the rate of respiratory crisis and a significant improvement in the clinical outcome, both likely related to earlier diagnosis and timely treatment. Despite the improved management, MuSK⁺ MG patients tend to remain dependent on long-term immunosuppressive treatment and may develop permanent disabling weakness. In uncontrolled studies, B cell depletion with rituximab proved effective in most patients with refractory disease, inducing prolonged clinical responses associated with a sustained reduction of serum antibody levels. Promising results from experimental studies and case reports suggest that both 3,4-diaminopyridine and albuterol may be effective as symptomatic agents.

Update in ethiopathogeny, diagnosis and treatment of the IgG4 related disease

IgG4 related disease (IgG4-RD) is probably an autoimmune pathology of unknown etiology. Diverse interactions participate in its pathogen between the adaptive and innate immune systems, activating lymphocytes B and T which trigger the inflammatory cascade, which culminates in fibrosis of the organs and their malfunction. It can affect a multitude of organs simultaneously. The diagnosis is based on the correlation of clinical findings with anatomopathological results (lymphoplasmocitary infiltrate, storiform fibrosis, obliterative phlebitis and IgG4+plasmatic cell count) and with the presence of elevated IgG4 in serum, depending on the criteria used. Corticoids and rituximab are among the few validated treatments available. There are multiple biomarkers and treatments in development. In this review, we aim to go over the principal pathogenic and clinical characteristics of IgG4-RD, as well as its handling, in accordance with the available scientific evidence.

A case of immunoglobulin G4-related lung disease with bilateral diffuse infiltration: A case report

RATIONALE

Immunoglobulin (Ig) G4-related disease (IgG4-RD) is a rare and chronic progressive autoimmune disease. It is a novel clinical entity characterized by elevated serum IgG4 concentration and tissue infiltration by IgG4 plasma cells. IgG4-related lung disease (IgG4-RLD) has been described as interstitial pneumonia and inflammatory pseudotumor, with various abnormal radiographic patterns. We report a case of IgG4-related lung disease with bilateral diffuse infiltration.

PATIENT CONCERNS

A 65-year-old woman was admitted to our hospital because of cough, sputum, and fever. Chest computed tomography (CT) revealed multifocal areas of consolidations, nodules, and ground glass opacities in both lungs. She still had fever after anti-infective therapy.

DIAGNOSES

Bronchial bronchoscopy and percutaneous lung biopsy were performed, resulted in a pathological diagnosis of IgG4-RLD.

INTERVENTIONS

The patient was started on oral prednisolone 30 mg/day for 28 days, and then was gradually tapered.

OUTCOMES

After one week treatment, the temperature was stable, CT showed significant improvement in the areas of consolidations and nodules.

LESSONS

It is a typical case of IgG4-RLD. This case indicated that suggestive evidence, radiological appearances, serum tests, pathological characteristics, and classic therapy IgG4-RLD. It is a rare disease that needs our more attention in future.

Polymyositis with elevated serum IgG4 levels and abundant IgG4+ plasma cell infiltration: A case report and literature review

INTRODUCTION

Polymyositis (PM) is a type of autoimmune, inflammatory myopathy. IgG4-related disease (IgG4-RD) is a recently recognized disease entity characterized by elevated serum IgG4 levels and IgG4 plasma-cell infiltration of various organs. However, several reports have described cases of other diseases that present with those features, suggesting the importance of careful differential diagnosis. Herein, we report the first case of PM with elevated serum IgG4 levels and IgG4 plasma cells in the muscles, mimicking IgG4-RD.A 73-year-old woman visited our hospital because of proximal muscle weakness of both thighs. Her blood test showed high levels of serum creatinine kinase, aldolase, and IgG4. Magnetic resonance imaging of the thighs showed muscle edema. Needle electromyography showed findings typical of myositis. Histological analysis of her left quadriceps revealed infiltration of IgG4 plasma cells as well as CD8 T cells. Scattered necrotic and regenerating muscle fibers with no specific findings for IgG4-RD (storiform fibrosis and obliterative phlebitis) were typical for PM. We diagnosed her condition as PM and treated her with 40 mg/day of prednisolone that decreased levels of muscle enzymes and improved muscle weakness.

CONCLUSION

Our case indicated that PM could present with high serum IgG4 levels and IgG4 plasma-cell infiltration, mimicking IgG4-RD. Although the mechanism of IgG4 elevation in such PM is unclear, our case highlights the necessity to recognize that high serum IgG4 levels and IgG4 plasma-cell infiltration in organs are not specific for IgG4-RD.

The autoimmune IgG4 -associated endocrine pathology

Immunoglobulin G4-associated diseases (IgG4-AD) arethe group of chronic progressive autoimmune fibro-inflammatory pathology of various organs and tissues, characterized by their enlargement and abundant infiltration of immunoglobulin G4-positive plasma cells, as well as an increase in the level of serum immunoglobulin G4 (IgG4).In most patients, the disease is characterized by a mild course.However, there is evidence of a high incidence of malignancies in patients with IgG4-AD.Among endocrine IgG4-associated pathologies, pancreatitis with outcome in diabetes mellitus, hypophysitis and thyroiditis are described. Laboratory examination usually reveals an increased level of IgG4. However, the concentration of IgG4 could not be used as the only diagnostic criterion.The possibility of plasmablastsdetermining as a marker of the disease is discussed.Among the imaging techniques CT, MRI and 18F-FDG-PET/CT are used.However, the most informative method of diagnosis is biopsy. Randomized clinical trials to determine clear recommendations for the treatment of IgG4-AD were not conducted.In most cases, glucocorticoids are prescribed, and immunosuppressive therapy is sometimes used.According to the results of recent studies, the genetically engineered drug rituximab is relatively effective in inducing remission of the disease.Given the high recurrence rate and the risk of malignancy, patients with IgG4-AD require careful long-term follow-up. Thus, the review describes the clinical manifestations of IgG4-AD, examines the possibilities of their diagnosis and presents the existing methods of treatment.However, given the fact that IgG4-AD became a separate group of autoimmune pathology less than 20 years ago, there are insufficient data on these diseases. Researches related to epidemiology, pathophysiology, diagnosis and effective treatment of IgG4-AD are actual.

IgG4-Related Disease: A Reminder for Practicing Pathologists

IgG4-related disease (IgG4-RD) is a systemic autoimmune fibroinflammatory disease that produces sclerotic, tumefactive masses containing dense lymphoplasmacytic infiltrates rich in immunoglobulin (Ig) G4+ plasma cells. Initially characterized as a form of autoimmune pancreatitis, the distinctive histopathology of IgG4-RD has now been described in almost every organ system. However, because the clinical manifestations of IgG4-RD are diverse and nonspecific, the disease may go unsuspected until a biopsy or resection specimen is obtained to diagnose a presumed malignancy. Pathologists thus play a key role in the diagnosis of IgG4-RD, and familiarity with its histopathologic features is essential to preventing the irreversible comorbidities associated with this treatable disease. This brief review outlines the epidemiology, clinical manifestations, and histopathology of IgG4-RD, with the aim of furthering pathologists' awareness of and ability to diagnose this disorder.

Thoracic involvement in IgG4-related disease in a UK-based patient cohort

IgG4-related disease (IgG4-RD) is a multi-system fibro-inflammatory disorder with classical histopathological findings, often in the context of elevated serum IgG4 levels. The thoracic manifestations of IgG4-RD are numerous and can mimic several common and better known conditions. The objective of this study was to outline the frequency and nature of thoracic involvement in a prospective cohort of IgG4-RD patients who met defined diagnostic criteria. Over 40% of IgG4-RD patients had clinicoradiological and/or histological evidence of thoracic involvement, predominantly mediastinal lymphadenopathy, the majority associated with multi-system disease outside the chest. Thoracic involvement was associated with a higher serum IgG4 level, potentially representing greater disease activity or spread. Our data highlight the diverse nature of thoracic IgG4-RD, and the importance of knowledge and recognition of the condition among respiratory physicians who are likely to encounter this disease entity on an increasing basis.

[IgG4-associated diseases : State of the art]

CLINICAL ISSUE

IgG4-related diseases are rare but the incidence is continuously increasing. The pathophysiology is only incompletely understood. Multiorgan involvement correlates with high relapse rates, high serum IgG4 levels and an aggressive disease course, which is why diagnostics and therapy must be carried out rapidly and efficiently according to international guidelines despite all the difficulties.

STANDARD TREATMENT

Currently the therapeutic standard is initial therapy (induction therapy) with glucocorticosteroids over a longer period of time and if necessary followed by low-dose maintenance therapy. Steroids are also the first choice therapy for management of relapses. Refractory disease courses are a rare but relevant problem.

TREATMENT INNOVATIONS

The B‑cell depleting antibody rituximab has shown excellent results in terms of remission induction and also maintenance therapy. The good effectiveness profile is likely to change the current treatment regimen for IgG4-related diseases in the future.

DIAGNOSTIC WORK-UP

The current diagnostic algorithms applicable for several organ systems are based on four major pillars: (i) patient history and physical examination, (ii) serological diagnostics, (iii) organ swelling in the appropriately selected imaging procedure and (iv) the histological picture as gold standard.

PERFORMANCE

The currently used algorithms allow a diagnosis to be made in most cases.

ACHIEVEMENTS

IgG4-related diseases are a relevant differential diagnosis, particularly of malignant diseases. It is often a diagnosis by exclusion. An interdisciplinary approach is essential for rapid diagnostics and induction of therapy.

PRACTICAL RECOMMENDATIONS

In Europe IgG4 serum levels are just one of several diagnostic criteria. Imaging studies should be chosen according to the organ and disease manifestations.