Identification of relapse predictors in IgG4-related disease using multivariate analysis of clinical data at the first visit and initial treatment

Unraveling the Clinical Features and Outcomes of IgG4-Related Ophthalmic Disease

Background/Objectives: IgG4-related ophthalmic disease (IgG4-ROD), characterized by lymphoplasmacytic infiltration, fibrosis, and elevated IgG4 levels, presents diagnostic challenges while offering insights into immune-mediated inflammatory disorders. The aim of this study was to comprehensively examine the clinical features and outcomes of IgG4-ROD. Materials and Methods: A retrospective study was conducted on 33 patients diagnosed with IgG4-ROD, fulfilling the American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) criteria. The demographic characteristics of the IgG4-ROD patients were compared with those of 37 patients diagnosed with IgG4-related disease (IgG4-RD) in departments other than ophthalmology (IgG4-nonROD) at the same hospital during the same period. The patients diagnosed with IgG4-ROD were initially treated with glucocorticosteroid (GCS) monotherapy, GCS combined with steroid-sparing agents (SSAs; mycophenolate mofetil, azathioprine, hydroxychloroquine), biologic agent (rituximab) monotherapy, or watchful waiting. The primary outcome was the assessed treatment response at 6 months, and the secondary outcome was the evaluation of recurrence at 1 year after initial treatment. A response was evaluated as the absence of ocular signs and symptoms, either clinically or radiologically. Results: Eyelid swelling (17 patients, 51.5%) was the most common symptom, and lacrimal gland (17 patients, 51.5%) was the most frequent site of involvement. The response rate for GCS monotherapy was 33.3% (3 out of 9 patients), while the response rate for GCS combined with SSA was 60.0% (9 out of 15 patients). The lacrimal gland group demonstrated a significantly higher treatment response compared to the non-lacrimal gland group (66.7% vs. 20.0%, p = 0.013), and the combination of GCS and SSA resulted in a significantly higher treatment response than the GCS monotherapy (77.8% vs. 33.3%, p = 0.045). The group including hydroxychloroquine (HCQ), which comprised 5 out of 33 patients (15.2%), showed no recurrence at 1 year. Conclusions: The combination therapy of GCS and SSA for IgG4-ROD can be considered an effective treatment approach and HCQ could be considered as a potential adjunctive therapy for IgG4-ROD.

An overlapping case of IgG4-related disease and systemic lupus erythematosus treated with belimumab: a case-based review

IgG4-related disease (IgG4-RD) is a systemic condition in which IgG4+ plasma cell infiltration and fibrosis cause organ swelling and lead to diverse clinical manifestations. Although IgG4-RD typically responds to glucocorticoids (GCs), relapse during tapering occurs and an early GC-sparing approach might therefore be beneficial. Systemic lupus erythematosus (SLE) is a chronic inflammatory disease with multiple symptoms that is also treated with GCs as a first-line therapy. Recently, belimumab, a recombinant human IgG-1λ monoclonal antibody that inhibits B-cell activating factor, was approved, but reports of use for IgG4-RD are scarce. Here, we present a rare case of IgG4-RD complicated with SLE which was successfully treated with belimumab. A 67-year-old man was diagnosed with IgG4-RD based on a high serum IgG4 level and histopathological findings. Furthermore, he had pericardial effusion on echocardiography, and laboratory tests revealed thrombocytopenia, autoimmune hemolysis, positive anti-nuclear antibodies, positive anti-DNA antibodies, and hypocomplementemia. These data led to an SLE diagnosis. Treatment was started with prednisolone at 40 mg/day, plus hydroxychloroquine, which initially improved both the SLE and IgG4-RD symptoms. During the GC tapering, belimumab was added and clinical symptoms resolved completely. Our case and the literature review summarize reported rare overlapping cases of IgG4-RD and SLE and suggest that belimumab is a promising candidate for the treatment of IgG4-RD.

Treatment outcomes and their determinants of IgG4-related ophthalmic disease: a territory-wide cohort study

BACKGROUND

Oral corticosteroid remains the first-line treatment of IgG4-related ophthalmic disease, but steroid-dependence is common and serious. Factors associated with steroid dependence and relapse have to be further explored.

STUDY POPULATION

A city-wide, biopsy-proven, Chinese cohort.

METHODS

Retrospective, masked review of medical records, orbital images and histopathology reports.

RESULTS

There were 101 patients with at least 24-month follow-up. Up to 82% (82/101) received oral corticosteroid as first-line treatments, and 7 of them received also concomitant steroid-sparing agents (SSA)/biological agents as primary treatment. There was 61% (50/82) of patients required long-term corticosteroid (alone=23, with SSA=27) after 1.9±0.7 (range 1-5) relapses. When compared with the 21% (17/82) of patients who tapered corticosteroid successfully for 24 months, steroid dependence was associated with elevated baseline serum IgG4 level (94% vs 65%, p<0.01) and Mikulicz syndrome (46% vs 18%, p<0.05). Up to 13% (11/82) of patients tolerated residual disease after tapering off corticosteroid. There was 17% (17/101) of patients did not require any medications after biopsies. They were more likely to have debulking surgeries (71% vs 40%, p<0.05), discrete orbital lesions (65% vs 26%, p<0.05), normal baseline serum IgG4 level (24% vs 6%, p<0.05) and no Mikulicz syndrome (94% vs 61%, p<0.05).

CONCLUSION

In this cohort, 60% of patients required long-term maintenance oral corticosteroid. Elevated pretreatment serum IgG4 level and Mikulicz syndrome were associated with steroid dependence. Debulking surgery is an alternative for a subgroup of patients with discrete orbital lesions, normal baseline IgG4 level and no Mikulicz syndrome.

Clinical characteristics and outcome of autoimmune pancreatitis based on serum immunoglobulin G4 level: A single-center, retrospective cohort study

BACKGROUND

Autoimmune pancreatitis (AIP) has been linked with elevated immunoglobulin (Ig) G4 levels. The characteristics and outcomes of AIP based on serum markers have not been fully evaluated.

AIM

To compare clinical features, treatment efficacy, and outcome of AIP based on serum IgG4 levels and analyze predictors of relapse.

METHODS

A total of 213 patients with AIP were consecutively reviewed in our hospital from 2006 to 2021. According to the serum IgG4 level, all patients were divided into two groups, the abnormal group (n = 148) with a high level of IgG4 [> 2 × upper limit of normal (ULN)] and the normal group (n = 65). The t-test or Mann-Whitney U test was used to compare continuous variables. Categorical parameters were compared by the χ2 test or Fisher's exact test. Kaplan-Meier curves and log-rank tests were established to assess the cumulative relapse rates. Univariate and multivariate analyses were used to investigate potential risk factors of AIP relapse.

RESULTS

Compared with the normal group, the abnormal group had a higher average male age (60.3 ± 10.4 vs 56.5 ± 12.9 years, P = 0.047); higher level of serum total protein (72.5 ± 7.9 g/L vs 67.2 ± 7.5 g/L, P < 0.001), IgG4 (1420.5 ± 1110.9 mg/dL vs 252.7 ± 106.6 mg/dL, P < 0.001), and IgE (635.6 ± 958.1 IU/mL vs 231.7 ± 352.5 IU/mL, P = 0.002); and a lower level of serum complement C3 (100.6 ± 36.2 mg/dL vs 119.0 ± 45.7 mg/dL, P = 0.050). In addition, a lower number of cases with abnormal pancreatic duct and pancreatic atrophy (23.6% vs 37.9%, P = 0.045; 1.6% vs 8.6%, P = 0.020, respectively) and a higher rate of relapse (17.6% vs 6.2%, P = 0.030) were seen in the abnormal group. Multivariate analyses revealed that serum IgG4 [(> 2 × ULN), hazard ratio (HR): 3.583; 95% confidence interval (CI): 1.218-10.545; P = 0.020] and IgA (> 1 × ULN; HR: 5.908; 95%CI: 1.199-29.120; P = 0.029) and age > 55 years (HR: 2.383; 95%CI: 1.056-5.378; P = 0.036) were independent risk factors of relapse.

CONCLUSION

AIP patients with high IgG4 levels have clinical features including a more active immune system and higher relapse rate. Several factors, such as IgG4 and IgA, are associated with relapse.

Glucocorticoids in the treatment of IgG4-related disease-Prospects for new international treatment guidelines

Immunoglobulin G4-related disease (IgG4-RD) is a chronic fibro-inflammatory disease that may cause dysfunction in various organs. Worldwide multidisciplinary experts attending the Fourth International Symposium on IgG4-Related Disease in Japan in 2021 discussed treatments for IgG4-RD, especially glucocorticoid (GC) therapy. This review describes the efficacy, safety, and cost of treatments for IgG4-RD based on findings presented at the international symposium. A medium dose of GC was considered appropriate for the initial treatment of IgG4-RD. A randomized controlled trial and an open-label prospective study have shown that long-term maintenance GC therapy (prednisolone ≥ 5 mg/day) could prevent disease relapse. In addition, two open-label randomized controlled trials reported the effects of combinational use of GC and synthetic immunosuppressive agents, mycophenolate mofetil and leflunomide, on relapse prevention. Moreover, an open-label single-arm study showed an excellent rate of clinical response to rituximab. Many observational studies have shown the efficacy of an appropriate GC regimen in patients with IgG4-RD. Synthetic immunosuppressive agents and a molecular-targeted agent can be potent alternatives to GCs, but additional studies are required comparing their efficacy, risk of infection, and costs.

Spontaneous regression of immunoglobulin G4-related dacryoadenitis and multiple organ involvement: A case report

PURPOSE

Immunoglobulin G4 (IgG4)-related dacryoadenitis is rarely resolved spontaneously without steroids. Here, we report a case of IgG4-related dacryoadenitis and extra-ophthalmic lesions with spontaneous regression.

METHODS

This is a clinical case report. A 56-years-old man had a 1-year and 7-month-old histories of neck and eyelid swelling, respectively. On the first examination, the lacrimal and submandibular glands were palpable bilaterally. Computed tomographic images showed enlargement of the lacrimal gland on both sides, right pulmonary hilar lymph node, and pancreas, and thickening of the abdominal aortic wall. Blood tests demonstrated elevated serum IgG4 level and positive hepatitis B surface antibody. Pathological examination of the biopsied lacrimal gland specimens revealed marked IgG4-positive plasma cell infiltration.

RESULTS

The patient was monitored carefully without steroid administration. Serum IgG4 level had gradually decreased during follow-up period and reached the normal range 3 years after the biopsy. At 4-year follow-up, the lacrimal and submandibular glands were not palpable on either side. Computed tomographic images demonstrated no enlargement of the lacrimal gland, submandibular gland, or lymph nodes, and improvement of the enlarged pancreas and thickened abdominal aortic wall.

CONCLUSION

Our case indicates that careful observation can be an option in selected cases with risks of steroid treatment or silent clinical course.

Serum IgG4 level during initial treatment as a predictor of relapse in IgG4-related disease

INTRODUCTION

We aimed to investigate the predictors of relapse in immunoglobulin G4-related disease (IgG4-RD), focusing on the serum IgG4 levels during initial treatment.

METHODS

We retrospectively recruited 57 patients with IgG4-RD who were treated with immunosuppressants and elevated serum IgG4 levels in a tertiary hospital between January 2011 and December 2020. They were followed up for ≥ 6 months after initiation of immunosuppressive therapy. Clinical and laboratory findings including serum IgG4 levels (reference value: 6-121 mg/dL) were compared between relapsed (n = 13) and non-relapsed (n = 44) groups. Multivariate Cox regression analysis was used to assess the predictors for relapse. We performed a Kaplan-Meier analysis with a log-rank test to evaluate the cumulative relapse rate for two years.

RESULTS

Median serum IgG4 levels at baseline were 321 mg/dL in the relapsed group and 299 mg/dL in the non-relapsed group. Serum IgG4 levels were normalized after six months in five (38.5%) relapsed and 28 (63.6%) non-relapsed patients. In multivariate Cox regression analysis, the normalization of serum IgG4 levels at six months was associated with a lower risk of relapse, with a hazard ratio of 0.232 (p = 0.019). Central nervous system involvement was associated with the relapse, with a hazard ratio of 21.130 (p = 0.015). The cumulative relapse rate for two years was lower in the normal serum IgG4 group at six months than in the elevated serum IgG4 group at six months (p = 0.027).

CONCLUSION

Our study suggests that normalization of serum IgG4 levels during immunosuppressive treatment for IgG4-RD independently predicts relapse-free outcomes. Thus, monitoring serum IgG4 levels might be used as a marker of prognosis.

CD4+CD8+ T follicular helper cells regulate humoral immunity in chronic inflammatory lesions

T follicular helper (Tfh) cells drive humoral immunity by facilitating B cell responses at the initial and recall phases. Recent studies have indicated the possible involvement of Tfh cells in the process of chronic inflammation. However, the functional role of Tfh cells in persistent immune settings remains unclear. Here, we report that CD4⁺CD8⁺ (double-positive, DP; CD3⁺CD4⁺CD8⁺CXCR5^hiPD-1^hi) Tfh cells, a subset of germinal-center-type Tfh cells, were abundantly present in the fibroinflammatory lesions of patients with immunoglobulin G4-related disease (IgG4-RD). Transcriptome analyses showed that these DP-Tfh cells in the lesions of IgG4-RD preferentially expressed signature genes characteristic of cytotoxic CD8⁺ T cells, such as Eomes, CRTAM, GPR56, and granzymes, in addition to CD70. Scatter diagram analyses to examine the relationships between tissue-resident lymphocytes and various clinical parameters revealed that the levels of DP-Tfh cells were inversely correlated to the levels of serum IgG4 and local IgG4-expressing (IgG4⁺) memory B cells (CD19⁺CD27⁺IgD^-) in patients with IgG4-RD. Cell culture experiments using autologous tonsillar lymphocytes further suggested that DP-Tfh cells possess a poor B-cell helper function and instead regulate memory B cells. Since CD4⁺ (single positive, SP; CD3⁺CD4⁺CD8^-CXCR5^hiPD-1^hi) Tfh cells differentiated into DP-Tfh cells under stimulation with IL-2 and IL-7 as assessed by in vitro experiments, these data imply that SP-Tfh cells are a possible origin of DP-Tfh cells under persistent inflammation. These findings highlight the potential feedback loop mechanism of Tfh cells in immune tolerance under chronic inflammatory conditions. Further studies on DP-Tfh cells may facilitate control of unresolved humoral responses in IgG4-RD pathological inflammation.

Clinical characteristics and therapeutic response of immunoglobulin G4-related disease: a retrospective study of 127 Chinese patients

Background and aims

Immunoglobulin G4-related disease (IgG4-RD) is a multisystem fibroinflammatory condition. The aim of the present study was to characterize the clinical features and therapeutic response of patients with IgG4-RD and identify risk factors for disease relapse.

Methods

We collected baseline data of eligible patients with IgG4-RD and analyzed clinical features by interview and review of medical records. The patients who received glucocorticoids (GC) therapy with at least 3 months follow-up were used to characterize the therapeutic response and identify risk factors for relapse.

Result

Totally 127 IgG4-RD patients, including 92 males and 35 females, were enrolled in the present study. The median age of onset was 63.0 years, ranging from 23 to 86. The pancreas, bile duct and lymph nodes were the most frequently involved organs. The serum IgG4 level was elevated in 94.5% of the patients and was correlated with the number of organs involved. Patients classified as head and neck limited group were more likely to be female. Compared to Mikulicz syndrome and systemic involvement group, pancreato-hepatobiliary group had higher aminotransferase, alkaline phosphatase, gamma-glutamyl transpeptidase, bilirubin and lower IgG4 level. Mikulicz syndrome and systemic involvement group had the highest IgG4-RD RI score, IgG level. Among 92 patients who received medical therapy with at least 3 months follow-up, 76 received GC alone or in combination with immunomodulator (IM) and 16 patients did not take GC. 74 out of the 76 patients (97.3%) achieved remission, with 59 of them remained in remission and 15 of them relapsed. Whereas 16 patients did not take GC, among them, 6 patients achieved remission with one relapsed. On multivariate analysis, higher initial score of ACR/EULAR IgG4-RD Classification Criteria and GC withdrawal were independent predictors for relapse.

Conclusion

Four phenotypes of IgG4-RD showed different demographic and serological features. GC + IM therapy was safe and effective and might protect patients from relapse. The independent risk factors of relapse were GC withdrawal and higher score of ACR/EULAR IgG4-RD Classification Criteria.

Steroid therapy still plays a crucial role and could serve as a bridge to the next promising treatments in patients with IgG4-related sclerosing cholangitis: Results of a Japanese Nationwide Study

OBJECTIVE

The acceptable duration of steroid therapy for patients with IgG4-sclerosing cholangitis (SC) has been under debate. Our aim is to clarify the feasible duration of steroid treatment.

DESIGN

We retrospectively reviewed the data of patients with IgG4-SC and analyzed the following: biliary status during the steroid therapy, incidence of remission, relapse, relapse-free survival rate, and steroid-related complications (SRCs).

RESULTS

Remission was achieved 99.5% (763/767) of patients who received steroid therapy, while remission rate dropped to 63.6% (78/129) of patients who didn't receive it. Relapse was noted in 19.7% (151/763) of the patients who received steroid. Besides, relapse rate went up 38.4% (30/78) of the counterpart. Normalization of the serum total bilirubin and serum alkaline phosphatase (ALP) levels were achieved at two weeks regardless of biliary drainage. Multivariate analysis identified younger onset, MST less than three years, immunosuppressant, and steroid cessation as independent risk factors for relapse. Steroid-free was achieved in the patients underwent MST only 3.4% over 54 months. SRCs were recorded in a total of 99 patients (12.9%) despite sufficient preemptive medications. Multivariate analysis identified history of malignancy and immunosuppressant as independent risk factors for SRCs.

CONCLUSION

Steroid therapy should be continued for no less than three years to reduce the risk of relapse, with use of preemptive measures taken around five years. The biliary drainage might not be mandatory. Steroid as 1st line therapy could serve as a bridge to further promising treatments.

Persistent enlargement of the pancreatic gland after glucocorticoid therapy increases the risk of relapse in IgG4-related autoimmune pancreatitis

OBJECTIVES

This study aims to clarify the relationship between the changes of pancreatic size after glucocorticoid (GC) therapy and relapse in IgG4-related autoimmune pancreatitis (AIP).

METHODS

We prospectively enrolled 205 newly diagnosed IgG4-related AIP patients. 145 patients were followed up for more than 3 years. These patients were divided into three groups according to the changes of pancreatic size after treatment of 6 months: pancreatic swelling, normal size, and pancreatic atrophy. Baseline clinical and laboratory parameters were compared among three groups. Kaplan-Meier survival analysis was performed in the 134 patients based on GC therapy. Besides, Cox regression analysis and logistic regression analysis were performed to identify risk factors associated with relapse and the potential variables affecting changes of pancreatic size after treatment.

RESULTS

Age at diagnosis, white blood cell count, and serum IgG1 level at baseline were significantly different among the three groups. After treatment of 6 months, the pancreas of most patients (n = 81, 55.9%) could return to normal size, while persistent pancreatic swelling was found in 24.1% patients (n = 35), and atrophy was observed in 20.0% of the patients (n = 29). Kaplan-Meier survival analysis presented patients with pancreatic swelling after 6 months of GC therapy were more likely to relapse in the follow-up of 3 years. Persistent pancreatic swelling after treatment and salivary gland involvement at baseline were independent risk variables associated with relapse in IgG4-related AIP patients, while GC-based therapy was a protective factor of relapse. Logistic regression analysis revealed that older age at diagnosis was associated with pancreatic atrophy and higher baseline serum IgG1 level was associated with pancreatic swelling after treatment of 6 months.

CONCLUSIONS

Patients with persistent pancreatic swelling after GC-based therapy of 6 months were more likely to relapse in the follow-up of 3 years. Older age at diagnosis and higher baseline serum IgG1 level were potential variables associated with pancreatic atrophy or swelling after treatment of 6 months. Key Points • Patients with persistent pancreatic swelling after glucocorticoid-based therapy were more likely to relapse in IgG4-related autoimmune pancreatitis. • Older age at diagnosis was associated with pancreatic atrophy after glucocorticoid-based therapy. • Higher baseline serum IgG1 level was associated pancreatic swelling after glucocorticoid-based therapy.

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.

Clinical Outcomes of IgG4-Related Ophthalmic Disease and Idiopathic Sclerosing Orbital Inflammation

PURPOSE

To compare the clinical features, treatment outcomes, and prognoses of immunoglobulin G4-related ophthalmic disease (IgG4-ROD) and idiopathic sclerosing orbital inflammation (ISOI).

METHODS

This retrospective case series included 40 and 22 biopsy-proven cases of IgG4-ROD and ISOI, respectively. The authors reviewed medical charts and images to determine the clinical presentation, involvement pattern, and treatment outcomes. The main outcome measures were differences in disease manifestation, treatment modalities and efficacy, medication-free remission rate, and predictive factors for remission.

RESULTS

The median ages were 51 (range 31-72) and 39 (range 9-73) years in the IgG4-ROD and ISOI groups, respectively. The most frequently involved sites were the lacrimal gland (39 cases, 98%) in IgG4-ROD patients and the extraconal region (15 cases, 68%) in ISOI patients. No significant difference was observed in the initial treatment response between the groups. Medication-free remission was achieved in 22 (55%) IgG4-ROD patients and 10 (45%) ISOI patients; none of the IgG4-ROD patients showed permanent ocular dysfunction, while half of the ISOI patients had permanent visual loss or limited ocular motilities. Multivariate analysis indicated that extraocular muscle enlargement (odds ratio, 0.11; 95% confidence interval, 0.01-0.98) and IgG4:IgG ratio on histopathology (odds ratio, 0.08; 95% confidence interval, 0.01-0.86) were negatively associated with medication-free remission in IgG4-ROD patients.

CONCLUSIONS

Although IgG4-ROD and ISOI share common histological findings of mass-forming sclerosis, IgG4-ROD frequently has a more indolent clinical course, whereas ISOI often demonstrates a more aggressive clinical course, resulting in ocular dysfunction even after remission. Different pathogeneses may account for the different disease characteristics.

Renal Involvement in Retroperitoneal Fibrosis: Prevalence, Impact and Management Challenges

Retroperitoneal fibrosis (RPF) is a rare disorder consisting of idiopathic and various secondary forms and characterized by chronic inflammatory infiltrates and marked fibrosis in the retroperitoneal space. In idiopathic RPF (IRPF), 35–60% of cases have been reported to be IgG4-related RPF, the retroperitoneal lesions of IgG4-related disease (IgG4-RD). IRPF can frequently lead to renal insufficiency mediated by urinary tract obstruction and hydronephrosis irrespective of being IgG4-related or not. Clinical pictures, laboratory and imaging findings, and location of the urinary tract obstruction are generally similar in IgG4-related and non-IgG4-related IRPF although multiple organ involvement and serum IgG4 elevation may be characteristic of the IgG4-related forms. Periaortic/periarterial lesions are the most frequent cause of renal insufficiency. Although the response to glucocorticoids is generally good, relapse does occur in a considerable proportion of patients, and may require an additional immunosuppressive agent and/or urological intervention in cases with multiple relapses or refractory obstructive uropathy. In general, the prognosis of patients with IRPF is good, but careful attention needs to be paid to chronic kidney disease as a major complication and rupture of the affected aorta/artery as a life-threatening one. Further studies are necessary to better understand the pathogenesis of the disease and to establish the optimal diagnostic and therapeutic strategies for it.

Differences in clinical characteristics of IgG4-related disease across age groups: a prospective study of 737 patients

OBJECTIVE

The aim of this study was to compare the clinical characteristics of IgG4-related disease (IgG4-RD) among different age groups.

METHODS

We conducted a prospective study of 737 patients who were newly diagnosed with IgG4-RD and compared detailed demographic features, organ involvements, laboratory tests, treatments and outcomes across age groups. The patients were divided into five groups according to their age at diagnosis: ≤39, 40-49, 50-59, 60-69 and ≥70 years. The clinical characteristics of paediatric patients were also described.

RESULTS

Sex ratio, disease duration, allergy history and clinical symptoms were significantly different across age groups. Besides, the proportions of superficial organ involvement (lacrimal gland and sinus) decreased with age, while the proportions of internal organ involvement (pancreas, biliary tract, retroperitoneal tissue, lung and prostate) increased with age, which was more prominent in male patients. Mikulicz's disease was the most common manifestation (70%) in paediatric IgG4-RD patients. Multiple Cox analysis identified that age ≤56 years at diagnosis was an independent risk factor of relapse.

CONCLUSION

We revealed the impact of age on clinical characteristics of IgG4-RD, which indicated that different management might be required among different age groups.

The prevalence of extra-salivary gland complications in immunoglobulin G4-related sialadenitis

OBJECTIVES

To estimate the prevalence of extra-glandular lesions in patients with immunoglobulin G4-related sialadenitis (IgG4-RS).

METHODS

Six electronic databases (PubMed, EMBASE, Science Direct, Scopus, Web of Science, and China National Knowledge Infrastructure) were systematically searched from the date of inception of each database to March 2021. The Strengthening the Reporting of Observational Studies in Epidemiology statement was used to conduct methodological quality assessment, and a random-effect meta-analysis model was applied to estimate the prevalence. Publication bias was visually assessed using a funnel plot and calculated via Begg's and Egger's tests. The Stata 15 software was used to perform data analysis.

RESULTS

A total of 43 articles comprising 1,864 patients with IgG4-RS were considered to be eligible for this study. The pooled prevalence of extra-salivary gland lesions in IgG4-RS was 76.53% with a confidence interval (CI) of (69.39%, 83.04%). A higher prevalence was associated with studies published before or during 2015 (84.38%, CI [74.23%, 92.58%]) than those published after 2015 (68.55%, CI [58.44%, 77.88%]). Lacrimal gland involvement (54.68%, CI [45.61%, 63.60%]) and lymph node swelling (56.96%, CI [48.16%, 65.56%]) were the most frequent lesions.

CONCLUSIONS

Extra-glandular lesions were common in patients with IgG4-RS. More high-quality prospective studies with less heterogeneity are required to determine the accurate prevalence.

B cell targeted therapy for immunoglobulin G4-related disease

Glucocorticoids are the first-line drug for the remission induction therapy of immunoglobulin (Ig) G4-related disease. Achieving drug-free remission using glucocorticoids alone is difficult, however, and many patients require maintenance therapy with glucocorticoids and immunosuppressants. Studies have recently found that the number of peripheral memory B cells and plasmablasts is increased in IgG4-related disease and have indicated the efficacy of rituximab, which, in remission induction therapy, rapidly reduces serum IgG4 levels and has the tapering effect of glucocorticoids. Rituximab has been shown to reduce the risk of relapse more than oral immunosuppressants such as azathioprine. However, maintaining drug-free remission is difficult with a single course of rituximab alone, and many cases require maintenance therapy with rituximab. This article outlines the potential of B-cell targeted therapy, focusing on the efficacy, and safety of rituximab for IgG4-related disease.

Relapse predictors and serologically unstable condition of IgG4-related disease: a large Chinese cohort

OBJECTIVES

Patients with IgG4-related disease (IgG4-RD) typically respond well to initial glucocorticoid therapy, but always relapse with tapered or maintenance dosage of steroid. We aimed to identify the risk factors for relapse of IgG4-RD and explore the impact of active intervention on the serologically unstable condition.

METHODS

We performed a retrospective study of 277 IgG4-RD patients at Peking University People's Hospital from February 2012 through February 2019. They were all followed for >4 months. The primary outcome was patient relapse. Data on recurrence of IgG4-RD symptoms, laboratory and image findings were recorded, along with information on treatment in the serologically unstable condition.

RESULTS

The cumulative relapse rate was 12.86%, 27.84% and 36.1% at 12, 24 and 36 months, respectively. Younger age at onset, younger age at diagnosis, longer time from diagnosis to treatment and history of allergy were associated with relapse. Identified independent risk factors were longer time from diagnosis to treatment and history of allergy. When serum IgG4 level was 20%, 50% or 100% higher than that of the remission period, similar percentages of patients finally relapsed, regardless of whether they were in the immunosuppression intensified or non-intensified group. Median duration from serum IgG4 level instability to relapse in the intensified and non-intensified group was not statistically different.

CONCLUSION

The risk factors of relapse were longer time from diagnosis to treatment and history of allergy. Intervention in the serologically unstable condition was not helpful for reducing relapse rate.

Identification of Markers Predicting Clinical Course in Patients with IgG4-Related Ophthalmic Disease by Unbiased Clustering Analysis

Purpose: To describe the clinical features of patients with immunoglobulin G4 (IgG4)-related ophthalmic disease (IgG4-ROD) grouped by unbiased cluster analysis using peripheral blood test data and to find novel biomarkers for predicting clinical features. Methods: One hundred and seven patients diagnosed with IgG4-ROD were divided into four groups by unsupervised hierarchical cluster analysis using peripheral blood test data. The clinical features of the four groups were compared and novel markers for prediction of clinical course were explored. Results: Unbiased cluster analysis divided patients into four groups. Group B had a significantly higher frequency of extraocular muscle enlargement (p < 0.001). The frequency of patients with decreased best corrected visual acuity (BCVA) was significantly higher in group D (p = 0.002). Receiver operating characteristic (ROC) curves for the prediction of extraocular muscle enlargement and worsened BCVA using a panel consisting of important blood test data identified by machine learning yielded areas under the curve of 0.78 and 0.86, respectively. Clinical features were compared between patients divided into two groups by the cutoff serum IgE or IgG4 level obtained from ROC curves. Patients with serum IgE above 425 IU/mL had a higher frequency of extraocular muscle enlargement (25% versus 6%, p = 0.004). Patients with serum IgG4 above 712 mg/dL had a higher frequency of decreased BCVA (37% versus 5%, p ≤ 0.001). Conclusion: Unsupervised hierarchical clustering analysis using routine blood test data differentiates four distinct clinical phenotypes of IgG4-ROD, which suggest differences in pathophysiologic mechanisms. High serum IgG4 is a potential predictor of worsened BCVA, and high serum IgE is a potential predictor of extraocular muscle enlargement in IgG4-ROD patients.

Different factors underlie recurrent and de novo organ involvement in immunoglobulin G4-related disease

OBJECTIVES

In IgG4-related disease (IgG4-RD), relapse including recurrent organ involvement (ROI) and de novo organ involvement (DNOI) occurs frequently during the clinical course. This study aimed to clarify the differences between the risk factors underlying ROI and DNOI in IgG4-RD.

METHODS

We retrospectively investigated factors related to ROI and DNOI in 86 IgG4-RD patients. For assessment of factors related to ROI and DNOI, we performed uni- and multivariate Cox regression analyses. On stepwise multivariate analysis, we applied the variables with P < 0.1 in the univariate analysis and the predictors of relapse suggested in past reports.

RESULTS

During the mean follow-up period of 63.1 months, ROI was detected at 1.0-120 months after diagnosis in 20 patients, 4 of whom were not receiving glucocorticoid (GC) at the time of ROI. In contrast, DNOI was detected at 5.0-120 months after diagnosis in 15 patients, 8 of whom were not receiving GC at the time of DNOI. In the multivariate analysis, blood eosinophil counts at diagnosis [per 100/μl; hazard ratio (HR) 1.072 (95% CI 1.018, 1.129)] and continuation of GC [vs discontinuation or observation without GC; HR 0.245 (95% CI 0.076, 0.793)] had a significant impact on the time to DNOI, whereas age [HR 0.942 (95% CI 0.899, 0.986)] and ANA positivity [vs negativity; HR 6.632 (95% CI 1.892, 23.255)] had a significant impact on the time to ROI.

CONCLUSION

The present study suggests that the risk factors of ROI and DNOI are different in IgG4-RD, highlighting the need for different preventative strategies.

Efficacy and safety of iguratimod on patients with relapsed or refractory IgG4-related disease

OBJECTIVE

To evaluate the therapeutic efficacy and safety of iguratimod on patients with relapsed or refractory IgG4-related disease (IgG4-RD).

METHODS

We conducted a retrospective single-center study in 17 IgG4-RD patients admitted to Peking University People's Hospital. Patients were given iguratimod, 25 mg, twice daily and clinical data were collected at 0, 12, and 24 weeks. The baseline treatments include prednisone, cyclophosphamide, leflunomide, mycophenolate mofetil, and methotrexate. Clinical manifestation, IgG4-RD responder index (IgG-RD RI), serological indexes, gland ultrasound findings, and adverse drug effect were recorded. IgG4-RD RI scores < 3 and declining ≥ 2 were recognized as complete response (CR); IgG4-RD RI scores declining ≥ 2 but remaining ≥ 3 were recognized as partial response (PR). If a patient's IgG4-RD RI score was 3 at the beginning, PR was considered as a 1-point decrease after the therapy.

RESULTS

Serum IgG4 decreased significantly from 708 (321-902) mg/dl at baseline to 446 (138-396) mg/dl at 24 weeks (P = 0.0016). IgG4-RD RI decreased significantly from 9.79 ± 3.07 at baseline to 3.57 ± 1.09 at 24 weeks (P < 0.0001). Overall, 2 (14.3%) patients achieved CR, 11 (78.6%) patients achieved PR, and 1 (7.14%) patient had no response to treatment at week 24. Serum IgG level and salivary glands major diameter also decreased significantly at week 12 and 24 after treatment.

CONCLUSION

Iguratimod can be a therapeutic strategy to achieve remission in relapsed or refractory IgG4-RD patients inadequately responding to corticosteroid treatment with or without other immunosuppressant treatment. Key messages • Iguratimod was effective for relapsed or refractory IgG4-RD patients. • Iguratimod can improve the clinical symptoms of patients, reduce the serum IgG and IgG4 levels, and can also reduce the volume of involved glands.

Upregulation and pathogenic roles of CCL18-CCR8 axis in IgG4-related disease

Objectives: To determine the protein expression level, expressing cell types, and pathogenic roles of chemokine (C-C motif) ligand 18 (CCL18) and its receptor chemokine (C-C motif) receptor 8 (CCR8) in affected tissues of patients with IgG4-related disease (IgG4-RD).Methods: The protein expression levels of CCL18 in labial salivary glands (LSGs) assessed by immunofluorescence (IF) staining were compared among patients with IgG4-RD (n = 3), primary Sjögren's syndrome (pSS; n = 4), and control subjects (n = 5). CCL18 expression levels in macrophages, CD11c⁺ cells, B cells, and plasmacytes in LSGs were examined by double IF staining. The protein expression levels of CCR8 and expressing cells (T, B cells, and plasmacytes) in LSGs were also compared among patients with IgG4-RD, pSS, and control subjects by double IF staining. The effects of the CCL18-CCR8 axis on total IgG, IgG2, and IgG4 production by peripheral blood mononuclear cells (PBMCs) stimulated with CD40L, IL-4, IL-10, and IL-21 were examined by in vitro assays.Results: CCL18 was specifically upregulated in LSGs of patients with IgG4-RD, compared with only a few cells in pSS patients and none of the controls. The numbers of CCL18-producing macrophages, CD11c⁺ cells, and plasmacytes in LSGs were significantly higher in IgG4-RD patients than in pSS patients and control (p < .05, each). Many T and B cells and some plasmacytes expressed CCR8 in LSGs of IgG4-RD and pSS patients. CCL18 specifically enhanced IgG4 production by stimulated PBMCs.Conclusion: CCL18-CCR8 axis was upregulated in LSGs of patients with IgG4-RD, suggesting possible roles of this axis in the pathogenesis of IgG4-RD.Key messagesThe CCL18-CCR8 axis in labial salivary glands (LSGs) and lacrimal glands of IgG4-RD patients was specifically upregulated compared with primary Sjögren's syndrome and control subjects.This axis might be a potentially novel therapeutic target in IgG4-RD, based on its important etiopathogenic roles, such as chemotaxis of various cells, induction of fibrosis, and enhancement of IgG4 production.

Long-term outcomes of ocular adnexal lesions in IgG4-related ophthalmic disease

Aims

To determine the long-term outcomes of ocular adnexal lesions in immunoglobulin G4-related ophthalmic disease (IgG4-ROD).

Methods

This retrospective, non-randomised exploratory study included 82 patients with ocular adnexal lesions. We evaluated the long-term outcomes in 71 patients during the median follow-up period of 30 months, who underwent either watchful waiting (n=20; range 12–90 months) or systemic corticosteroid treatment, delivered according to consensus guidelines (n=51; range 9– 115 months). We also analysed factors that might contribute to recalcitrance to treatment.

Results

Of 82 patients, 40 (49%) were male, and the median patient age was 60 years old. Twenty-one (26%) patients with extraocular muscle (EOM) and/or trigeminal nerve branch (CN V) enlargements had a significantly high frequency of multiple ocular adnexal lesions (p<0.0001, Fisher’s exact test). In addition, two patients developed EOM and/or CN V enlargements de novo over time. Twenty patients with solitary lacrimal gland enlargements preferred watchful waiting, due to mild symptoms. Of these, 18 (90%) lesions remained dormant throughout a median follow-up of 27 months. Among 51 patients treated with corticosteroids, 31 (61%) experienced relapses after treatment and required systemic low-dose maintenance treatment. A multivariate analysis indicated that EOM and/or CN V enlargements comprised a risk factor for relapse (HR 2.7; 95% CI 1.1 to 6.7).

Conclusions

This exploratory study showed that different types of ocular adnexal lesions in IgG4-ROD displayed distinct proliferative activities. Our results suggested that EOM and/or CN V enlargements might be secondary lesions that confer refractoriness to systemic corticosteroid treatment recommended by consensus guidelines.

Retrospective single-centre analysis of IgG4-related disease patient population and treatment outcomes between 2007 and 2017

Objective

The aim was to gain a better understanding of the prevalence, organ involvement, clinical characteristics and long-term outcomes of medical and surgical treatments of IgG4-related disease (IgG4-RD).

Methods

Query of the Cleveland Clinic pathology database for IgG4 plasma cell staining between 2007 and 2017 yielded 1481 results, of which 57 cases were identified as highly likely (n = 28; 49%) or probable (n = 29; 51%) IgG4-RD by histopathological criteria and IgG4 serum concentrations. Patient demographics, type of treatment and outcomes were retrieved from medical records. Patients were designated as being in remission if indicated in the chart and/or symptom- and objective finding-free for >6 months, relapsed if symptoms/findings recurred after remission, active if no remission was achieved during follow-up, and as unable to determine if the duration of follow-up was <60 days or they were lost to follow-up.

Results

Of all patients who met the IgG4 staining criteria (n = 119), half (n = 57) satisfied the IgG4-RD histopathological criteria; 63% were males, age 57.9 ± 14.8 years. The average follow-up was 2.7 ± 2.2 years. The pancreas was the most affected organ in our cohort (26.4%). Almost half of the patients (45.6%; n = 26) were managed surgically, 21.1% (n = 12) medically, and 24.6% (n = 14) received both types of treatment. Medical treatment included prednisone (45.6%), MTX (5.3%), AZA (7%) and rituximab (8.8%). Remission was achieved by 77% of patients receiving surgical, 67% receiving medical and 72% receiving both treatments.

Conclusion

A histological diagnosis of IgG4-RD could be made in half of the patients who had IgG4⁺ plasma cells ≥10/high-power field or IgG4⁺/IgG⁺ ratio >40%. In our cohort, surgical treatment compared with medical treatment had a higher proportion of remission according to our outcome classification.

Relapse patterns and predictors of IgG4-related diseases involved with autoimmune pancreatitis: A single-center retrospective study of 115 patients

OBJECTIVE

Autoimmune pancreatitis is an autoimmune disorder accompanied by clinicopathological manifestations that have been established as immunoglobulin (IgG)4-related diseases (IgG4-RD). Other IgG4-RD are often involved with autoimmune pancreatitis. They sometimes relapse despite a favorable response to steroid therapy. This study aimed to clarify the patterns and risk factors for extrapancreatic relapse.

METHODS

We reviewed the data of 115 patients diagnosed with definite autoimmune pancreatitis type 1 and followed up for > 1 year. We analyzed two items: the timing and pattern of extrapancreatic relapse, and risk factors for relapse with three common manifestations: IgG4-related sclerosing cholangitis (SC), IgG4-related dacryoadenitis and sialadenitis (DS), and IgG4-related retroperitoneal fibrosis (RF).

RESULTS

Remission was achieved in all patients, except one. The extrapancreatic relapse rates were 11.0%, 19.7%, and 40% within 3, 5, and 10 years, respectively. Of 26 patients with extrapancreatic relapse, nine (34.6%) relapsed with a new IgG4-RD. Based on multivariate analysis, the interval between symptom onset and steroid initiation, and the presence of RF at onset were significant risk factors for relapse with SC and RF, respectively.

CONCLUSIONS

Our results indicate that they may be various extrapancreatic relapse patterns especially in autoimmune pancreatitis with other organ involvement. Patients with a delayed initiation of steroids or RF at onset should be carefully followed up as high-risk groups for SC and RF relapse.

Impact of sclerosing dacryoadenitis/sialadenitis on relapse during steroid therapy in patients with type 1 autoimmune pancreatitis

OBJECTIVES

Steroids are the first-line drugs for induction of remission in patients with type 1 autoimmune pancreatitis (AIP), and the usefulness of steroid maintenance therapy to prevent relapse has recently been reported. However, even during steroid therapy, a relatively large percentage of patients relapse and the predictive factors for relapse have not yet been elucidated. The aim of this study was to clarify the predictive factors for relapse of AIP patients during steroid therapy.

MATERIALS AND METHODS

The medical records of 76 patients with type 1 AIP with continued steroid therapy after induction of remission were analyzed retrospectively. The relapse rate during steroid therapy was evaluated, and the risk factors for relapse were investigated by univariate and multivariate analysis of clinical factors.

RESULTS

Relapse occurred in 28.9% (22/76) of the patients. The cumulative relapse rates were 10.5% at 1 year, 25.0% at 3 years, 34.9% at 5 years, and 43.0% at 10 years. In multivariate analysis, presence of sclerosing dacryoadenitis/sialadenitis at the time of initial diagnosis of AIP was an independent risk factor for relapse (HR 3.475, p = .009). The cumulative relapse rates of patients with sclerosing dacryoadenitis/sialadenitis reached 21.4% at 1 year, 56.0% at 3 years, and 78.0% at 5 years.

CONCLUSIONS

Sclerosing dacryoadenitis/sialadenitis was a predictive factor for relapse in type 1 AIP during steroid therapy; in such cases, strict follow-up is necessary with relapse in mind.

Differences and similarities between IgG4-related disease with and without dacryoadenitis and sialoadenitis: clinical manifestations and treatment efficacy

Background

This study aimed to compare the differences and similarities in the clinical manifestations and treatment efficacy of IgG4-related disease (IgG4-RD) in patients with and without dacryoadenitis and sialoadenitis (DS).

Methods

A total of 121 untreated IgG4-RD patients in Peking Union Medical College Hospital were enrolled in this study. The patients were divided into three groups: DS-predominant (group A), non-DS (group B), and DS with other internal organs affected (group C). The patients were followed up for at least 15 months. Baseline and follow-up data were collected. The disease activity was evaluated according to the IgG4-RD responder index.

Results

The mean ± SD age at disease onset was 53.2 ± 14.1 years, and 71.9% of the patients were male. The prevalence of allergies was higher in groups A (21, 61.8%) and C (32, 69.6%) than group B (14, 34.1%). More patients with DS (17, 50.0%, and 17, 37.0%) had sinonasal lesions than those without DS (5, 12.2%). Moreover, an increased number of eosinophils were more common in patients with DS than in those without, as were increased serum IgG, IgG4, and IgE levels. More patients in group B and group C (28, 68.3%, and 31, 67.4%) received a combination therapy of corticosteroid and immunosuppressant. During the 15-month follow-up, 28 (23.1%) patients had disease relapse.

Conclusion

Results demonstrated that IgG4-RD patients with DS had distinctive clinical features compared with non-DS. Allergy and sinonasal involvement were more common in patients with DS. Patients with DS showed higher serum IgG4 levels than those without DS.

Electronic supplementary material

The online version of this article (10.1186/s13075-019-1828-8) contains supplementary material, which is available to authorized users.

A case of recurrent Mikulicz's disease with mononeuritis multiplex

We report an 82-year-old man with recurrence of Mikulicz's disease accompanied with mononeuritis multiplex. On admission, both upper eyelids, the salivary gland, the dorsum of the left hand and both legs were swollen. Neurological examination showed motor weakness of distal limbs (manual muscle testing 3/5) and decreased touch, pain and vibration sensation of the dorsum of the left hand and both legs. Deep tendon reflex in both legs was also decreased. We diagnosed Mikulicz's disease based on high serum immunoglobulin (Ig)G4 (630 mg/dl, 26.1% of total IgG) and lacrimal gland biopsy findings. Clinical symptoms and motor conduction study findings improved after steroid therapy. However, tapering of the steroid dose resulted in recurrence two years later. Steroid therapy is usually effective for IgG4-related neuropathy, and we found that an increase of steroid dose was effective to treat the recurrence. But, in general, a suitable maintenance dose of steroid in combination with an immunosuppressant may be necessary to prevent relapse.

Sex disparities in clinical characteristics and prognosis of immunoglobulin G4–related disease: a prospective study of 403 patients

Objectives

To study the impact of sex on the clinical presentation of IgG4-related disease (IgG4-RD).

Methods

We prospectively enrolled 403 newly diagnosed IgG4-RD patients. We compared the demographic features, clinical manifestations, organ involvement, laboratory tests and treatment outcomes between female and male patients. The organs involved were divided into superficial organs (salivary glands, lacrimal glands, orbit, sinus and skin) and internal organs (all the other organs). The patients treated with glucocorticoids with or without additional immunosuppressants were included in the assessment of treatment outcomes, and potential confounding factors were corrected by propensity score matching or multivariate Cox regression analysis.

Results

Female patients showed younger age at both symptom onset and diagnosis, and a longer interval between symptom onset and diagnosis. Allergy history, Mikulicz’s disease and thyroiditis were more common in female patients, while autoimmune pancreatitis, sclerosing cholangitis and retroperitoneal fibrosis were more common in male patients. In accordance, female patients more frequently presented with superficial organ involvement, while male patients more frequently had internal organ involvement, and the discrepancy was more prominent in the patients with older age. Male sex was associated with higher peripheral eosinophils, CRP and IgG4 levels at baseline. In response to glucocorticoid-based therapies, male sex was associated with a higher IgG4-RD responder index during follow-up as well as a greater risk of relapse (hazard ratio 3.14, P = 0.003).

Conclusion

Our study revealed the sex disparities in clinical characteristics of IgG4-RD, and indicated that male sex was independently associated with worse prognosis in response to glucocorticoid-based therapies.

Rituximab Maintenance Therapy Reduces Rate of Relapse of Pancreaticobiliary Immunoglobulin G4-related Disease

BACKGROUND & AIMS

IgG4-related disease (IgG4-RD), a multi-organ fibroinflammatory syndrome, typically responds to steroids. However, some cases are steroid resistant, and pancreaticobiliary IgG4-RD commonly relapses after steroid withdrawal. Rituximab induces remission of IgG4-RD, but the need for and safety of maintenance rituximab treatment are unknown. We compared outcomes of patients with pancreaticobiliary IgG4-RD treated with or without maintenance rituximab therapy.

METHODS

We performed a retrospective study of patients with pancreaticobiliary IgG4-RD treated with rituximab at the Mayo Clinic in Rochester, Minnesota, from January 2005 through December 2015. The cohort was divided into patients who received only rituximab induction therapy (group 1, n = 14) and patients who received rituximab induction followed by maintenance therapy (group 2, n = 29). We collected data on recurrence of IgG4-RD symptoms and findings, as well as information on evaluations, treatment, and adverse events.

RESULTS

Median follow-up times were similar between group 1 (34 mo) and group 2 (27 mo) (P = .99). Thirty-seven patients (86%) were in steroid-free remission 6 months after rituximab initiation. A higher proportion of patients in group 1 had disease relapse (3-year event rate, 45%) than in group 2 (3-year event rate, 11%) (P = .034). Younger age, higher IgG4 responder index score after induction therapy, and increased serum levels of alkaline phosphatase at baseline or after rituximab induction were associated with relapse. Infections developed in 6 of 43 patients, all in group 2 (P = .067 vs group 1); all but 1 occurred during maintenance therapy.

CONCLUSIONS

In a retrospective study of patients with pancreaticobiliary IgG4-RD, we found rituximab maintenance therapy prolongs remission. Relapses are uncommon among patients receiving maintenance therapy, but maintenance therapy may increase risk of infection. Patients with factors that predict relapse could be candidates for rituximab maintenance therapy.

Factors in glucocorticoid regimens associated with treatment response and relapses of IgG4-related disease: a multicentre study

Glucocorticoids (GC) are effective for treating IgG4-related disease (IgG4-RD); however, relapse is often observed. We conducted a retrospective multicentre study to investigate risk factors in GC regimens associated with relapses of IgG4-RD. Data on 166 patients with definitive IgG4-RD diagnosis were collected from 12 institutions. Comprehensive surveillance of clinical backgrounds and GC regimens as well as multivariate analysis of factors associated with treatment responses and relapses was performed. To determine the initial maximal GC dose, the patients were stratified into three groups depending on the initial prednisolone (PSL) dosage: <0.39, 0.4–0.69 and >0.7 mg/kg/day. The multivariate analysis extracted the disease duration and reduction speed of initial GC dose. Patients treated with initial GC <0.39 or >0.7 mg/kg/day of PSL showed higher relapse rates than those treated with 0.4–0.69 mg/kg/day. The relapse rates were significantly higher in patients with fast reduction of the initial dose (>0.4 mg/day) than in patients with slow reduction (<0.4 mg/day). To avoid relapse, 0.4–0.69 mg/kg/day of initial PSL with slow reduction speed (<0.4 mg/day) is needed in the early treatment of IgG4-RD.

Long-term efficacy and safety of rituximab in IgG4-related disease: Data from a French nationwide study of thirty-three patients

OBJECTIVES

To assess efficacy and safety of rituximab (RTX) as induction therapy, maintenance of remission and treatment of relapses in a cohort of IgG4-related disease (IgG4-RD) patients.

METHODS

Nationwide retrospective multicenter study of IgG4-RD patients treated with at least one course of RTX. Clinical, biological and radiological response, relapse rate and drug tolerance were analyzed. Kaplan-Meier curves were plotted and risk factors for relapse studied with a Cox regression model.

RESULTS

Among 156 IgG4-RD patients included in the French database, 33 received rituximab. Clinical response was noted in 29/31 (93.5%) symptomatic patients. Glucocorticoids withdrawal was achieved in 17 (51.5%) patients. During a mean follow-up of 24.8 ±21 months, 13/31 (41.9%) responder patients relapsed after a mean delay of 19 ±11 months after RTX. Active disease, as defined by an IgG4-RD Responder Index >9 before RTX, was significantly associated with relapse (HR = 3.68, 95% CI: 1.1, 12.6) (P = 0.04), whereas maintenance therapy with systematic (i.e. before occurrence of a relapse) RTX retreatment was associated with longer relapse-free survival (41 versus 21 months; P = 0.02). Eight severe infections occurred in 4 patients during follow-up (severe infections rate of 12.1/100 patient-years) and hypogammaglobulinemia ≤5 g/l in 3 patients.

CONCLUSION

RTX is effective for both induction therapy and treatment of relapses in IgG4-RD, but relapses are frequent after B-cell reconstitution. Maintenance therapy with systematic RTX infusions is associated with longer relapse-free survival and might represent a novel treatment strategy. Yet, the high rate of infections and the temporary effect of RTX might be hindrances to such strategy.

IgG4-related disease in an adolescent with radiologic-pathologic correlation

Immunoglobulin G4–related disease (IgG4RD) is an immune-mediated condition characterized by lymphoplasmacytic infiltrates and fibrosis of affected organs. IgG4RD may affect many different organs either individually or together in a multiorgan condition and, thus, incorporates a wide range of fibroinflammatory phenotypes with shared pathologic features. Although IgG4RD most commonly occurs in late adulthood, it may affect children and adolescents. Only one case of IgG4RD presenting as isolated submandibular gland involvement has been reported in the pediatric population. Radiographic features of IgG4RD are often nonspecific making diagnosis challenging, but it is important for radiologists to be familiar with this diseased as its inclusion the differential for diffuse salivary enlargement may be the first step in making an accurate diagnosis. Here, we report a case of a child presenting with bilateral submandibular gland swelling to increase awareness of this condition in the pediatric population.

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.

Therapeutic approach to IgG4-related disease: A systematic review

To review the reported evidence on the therapeutic management of IgG4-related disease (IgG4-RD) in clinical practice.A systematic search of the literature was conducted. The primary outcome measured was the rate of efficacy of first-line therapeutic approaches. Secondary outcomes measured included the rate of disease relapse, the outcome of untreated patients, the rate of patients without drug therapy at the end of follow-up, the rate of side effects, and mortality. The MOOSE, AHRQ, STROBE, and GRACE recommendations/statements were followed.The results of the systematic search strategy yielded 62 studies that included a total of 3034 patients. Complete information about first-line therapeutic regimens was detailed in 1952 patients, including glucocorticoid-based regimens in 1437 (74%), drug-free regimens in 213 (11%), and other therapies in 38 (2%). No therapy (wait and see management) was reported in 264 (13%) patients. The efficacy of monotherapy with glucocorticoids was specified in 1220 patients, of whom 97% had a therapeutic response. Relapses, however, were reported in 464/1395 (33%) patients despite typically short follow-up periods. Therapeutic efficacy was reported in 219/231 (95%) of relapses treated with glucocorticoids, 56/69 (81%) of those treated with azathioprine, 16/22 (72%) of those treated with other immunosuppressive agents, and in the 9 cases treated with rituximab (100%). In 14 studies, the authors detailed the outcome of 159/246 patients with wait-and-see management; spontaneous improvement or resolution was reported in 68 (43%) cases. Wide heterogeneity was observed with respect to the first-line therapeutic approaches used for the different organ-specific disease subsets, including significant differences in the mean dose of glucocorticoids used.Nearly 70% of reported IgG4-RD patients are treated with oral glucocorticoids in monotherapy. However, the therapeutic management is heavily influenced by geographical, epidemiological, and clinical factors, especially with respect to the predominant organ affected. The frequency of glucocorticoid failure to induce sustained remissions both during and after treatment and the assessment of glucocorticoid toxicity in IgG4-RD require further study.

Predictors of disease relapse in IgG4-related disease following rituximab

OBJECTIVE

IgG4-related disease (IgG4-RD) is a relapsing-remitting condition responsible for fibroinflammatory lesions that can lead to organ damage and life-threatening complications at nearly any anatomical site. The duration of remission following treatment varies and predictors of relapse are unclear. The objectives of this study were to review our experience with rituximab as remission induction in IgG4-RD, to clarify the duration of efficacy and to identify predictors of flare following treatment.

METHODS

In this retrospective cohort study, all patients were treated with two doses of rituximab (1 g) separated by 15 days. Clinical, radiographic and laboratory data pertaining to rituximab response and disease relapse were collected from the electronic medical record. Kaplan-Meier curves were constructed to estimate the time to disease relapse. Log-rank analyses were performed to compare times to relapse among subgroups. Potential relapse predictors were evaluated with Cox regression analysis.

RESULTS

Fifty-seven of 60 patients (95%) had clinical responses to rituximab. Forty-one patients (68%) were treated without glucocorticoids. Twenty-one patients (37%) experienced relapses following treatment at a median time from the first infusion of 244 days. Baseline concentrations of serum IgG4, IgE and circulating eosinophils predicted subsequent relapses, with hazard ratios of 6.2 (95% CI: 1.2, 32.0), 8.2 (95% CI: 1.4, 50.0) and 7.9 (95% CI: 1.8, 34.7), respectively. The higher the baseline values, the greater the risk of relapse and the shorter the time to relapse. Only 10% of the patients had elevations of all three major risk factors, underscoring the importance of measuring all three at baseline.

CONCLUSION

Baseline elevations in serum IgG4, IgE and blood eosinophil concentrations all predict IgG4-RD relapses independently.

IgG4-Related Ophthalmic Disease: Pooling of Published Cases and Literature Review

In recent years, IgG4-related ophthalmic disease (IgG4-ROD) has emerged as a common cause of orbital inflammation, accounting for a substantial proportion of idiopathic orbital inflammation and lymphoid hyperplasia. The last pooled analysis of published cases was conducted in 2012, but a large number of new cases have been added to the literature since then. In this review, we present the demographic, clinical, histological, and treatment data for 172 published cases of biopsy-confirmed IgG4-ROD. Results are accompanied by a review of the relevant literature.

Recent developments in steroid-responsive pancreatitides (autoimmune pancreatitis)

PURPOSE OF REVIEW

There are two distinct steroid responsive chronic fibro-inflammatory diseases of the pancreas, called type 1 and type 2 autoimmune pancreatitis (AIP). We review recent progress in this field.

RECENT FINDINGS

It has recently been suggested that the term AIP be used to describe type 1 AIP and the term idiopathic duct-centric chronic pancreatitis (IDCP) be used for type 2 AIP. Clinical features and long-term outcomes of AIP and IDCP are well characterized and prognosis of both diseases is excellent. Diagnostic strategies tailored to regional practice patterns have emerged with the application of International Consensus Diagnostic Criteria for AIP. Although corticosteroids remain the mainstay of treatment, management of relapses and strategies for preventing multiple relapses are better understood, including the role of maintenance therapy and B-cell depletion therapy with rituximab. Association studies with malignancies have yielded conflicting results regarding risk of cancer in AIP.

SUMMARY

The treatment, follow-up guidelines and associations continue to evolve with our increasing experience with both AIP and IDCP. In AIP, rituximab can be used for both induction and maintenance of remission. IDCP responds to steroids without need for maintenance therapy. Both AIP and IDCP have excellent prognosis.

IgG4-related autoimmune diseases: Polymorphous presentation complicates diagnosis and treatment

BACKGROUND

IgG4-associated autoimmune diseases are systemic diseases affecting multiple organs of the body. Autoimmune pancreatitis, with a prevalence of 2.2 per 100,000 people, is one such disease. Because these multi-organ diseases present in highly variable ways, they were long thought just to affect individual organ systems. This only underscores the importance of familiarity with these diseases for routine clinical practice.

METHODS

This review is based on pertinent articles retrieved by a selective search in PubMed, and on the published conclusions of international consensus conferences.

RESULTS

The current scientific understanding of this group of diseases is based largely on case reports and small case series; there have not been any randomized controlled trials (RCTs) to date. Any organ system can be affected, including (for example) the biliary pathways, salivary glands, kidneys, lymph nodes, thyroid gland, and blood vessels. Macroscopically, these diseases cause diffuse organ swelling and the formation of pseudotumorous masses. Histopathologically, they are characterized by a lymphoplasmacytic infiltrate with IgG4-positive plasma cells, which leads via an autoimmune mechanism to the typical histologic findings--storiform fibrosis ("storiform" = whorled, like a straw mat) and obliterative, i.e., vessel-occluding, phlebitis. A mixed Th1 and Th2 immune response seems to play an important role in pathogenesis, while the role of IgG4 antibodies, which are not pathogenic in themselves, is still unclear. Glucocorticoid treatment leads to remission in 98% of cases and is usually continued for 12 months as maintenance therapy. Most patients undergo remission even if untreated. Steroid-resistant disease can be treated with immune modulators.

CONCLUSION

IgG4-associated autoimmune diseases are becoming more common, but adequate, systematically obtained data are now available only from certain Asian countries. Interdisciplinary collaboration is a prerequisite to proper diagnosis and treatment. Treatment algorithms and RCTs are needed to point the way to organ-specific treatment in the future.