Thoracic involvement and imaging patterns in IgG4-related disease

CT Chest findings in IgG4-related disease

PURPOSE

To investigate the multi-slice spiral Computed Tomography(MSCT) findings of chest involvement in IgG4-related diseases and to improve doctors' understanding of this disease.

MATERIALS AND METHODS

We retrospectively analyzed the clinical and imaging data of 67 patients with clinically confirmed or suspected IgG4-related diseases.

RESULTS

Sixty patients (89.60%) had abnormal chest CT findings. Among them, 47 patients (70.10%) had enlarged mediastinal lymph nodes. Thickening of the tracheal and tracheobronchial perivascular walls was observed in 35 patients (52.20%). Nodules were observed in 29 patients (43.30%). Patches or ground-glass opacities were observed in 15 cases (22.40%); bilateral enlarged axillary lymph nodes, 9 (13.40%); bilateral enlarged hilar lymph nodes, 3 (4.50%); and, interstitial changes, 3 (11.90%). Pleural and pericardial effusion occurred in five cases (7.46%, two bilateral and three unilateral) and three cases (4.50%), respectively. Seven (10.45%) patients showed no obvious abnormalities. The abnormally elevated IgG4 level (>135 mg/dL) was positively correlated with thickening of the tracheal and tracheobronchial walls (r = 0.328, p = 0.007) and enlargement of mediastinal lymph nodes (r = -0.252, p = 0.039), and the logistic regression model 1 showed that the incidence of lung as the first symptom was higher in patients with bilateral enlarged hilar lymph nodes on chest images.

CONCLUSION

Chest CT is of great significance for the diagnosis and follow-up of IgG4-RLD. Chest CT scans should be suggested to be performed when ocular symptoms, bilateral enlarged hilar lymph nodes, pancreatitis, pituitary adenitis, Takayasu arteritis, or abnormally elevated IgG4 levels (>135 mg/dL) are present, and IgG4-RLD should be considered.

Comments and Illustrations of the European Federation of Societies for Ultrasound in Medicine Guidelines: Benign Pleura Lesions (Benign Pleura Thickening, Lesions and Masses)-What Can Be Seen on Transthoracic Ultrasound?

Pleural thickening can be the result of inflammation or infection but can also have a neoplastic origin. Depending on the clinical context, a pleural lesion or mass is often initially suspected of malignancy. Benign pleural tumors are rare, and their appearance on ultrasound (US) is also described less frequently than pleural metastases or malignancies. There are few descriptions of contrast-enhanced Ultrasound (CEUS) in particular. This review introduces the basics of transthoracic ultrasound (TUS) of the pleura and CEUS of the pleura and lung. CEUS is recommended for pulmonary applications in the EFSUMB guidelines in non-hepatic applications. This article provides an overview of the characteristics of benign pleural thickening, tumor-like lesions, and benign pleural tumors on transthoracic B-mode US with color Doppler imaging (CDI) and CEUS. In detail, characteristics in TUS and CEUS are described for infectious/inflammatory pleural thickening (empyema, tuberculous pleuritis, hemothorax, fibrothorax), pleural thickening in various systemic diseases, in tumor-like conditions (plaques, splenosis, endometriosis, mesothelial cysts, lymphangiomatosis) and benign tumors (lipoma, benign SFT, schwannoma, solitary extramedullary/extraosseous plasmacytoma). The descriptions are illustrated by corresponding US and CEUS images.

Pulmonary manifestations, treatments and outcomes of IgG4-related disease-a systematic literature review

Immunoglobulin G4-related disease (IgG4-RD) is a multisystem fibroinflammatory condition. A consistent feature of many cases is pulmonary infiltrates, or respiratory failure. This systematic literature review aims to summarise the pulmonary manifestations of IgG4-RD, including clinical outcomes and treatment. This review was registered on PROSPERO (CRD42023416410). Medline, Embase and Cochrane databases were searched for articles discussing IgG4-RD syndrome. Information was extracted on demographics, type and prevalence of pulmonary manifestations, treatment and clinical outcomes. Initially, after deduplication, 3123 articles were retrieved with 18 ultimately included. A pooled total of 724 patients with IgG4-RD were included, 68.6% male, mean age 59.4 years (SD 5.8) at disease onset. The most frequently described pulmonary manifestation was mediastinal lymphadenopathy (n = 186, 48.8%), followed by pulmonary nodules (n = 151, 39.6%) and broncho-vascular thickening (n = 85, 22.3%). Where treatment was reported, the majority of patients received glucocorticoids (n = 211, 93.4%). Other immunosuppressive therapy included cyclophosphamide (n = 31), azathioprine (n = 18), with mycophenolate mofetil (n = 6), rituximab (n = 6), methotrexate (n = 5) and other unspecified immunomodulators (50). Clinical outcomes were reported in 263 patients, where 196 patients had remission of their disease, 20 had relapse, 35 had stable disease, four had progression and eight patients died from complications of IgG4-RD. This systematic review summarises pulmonary manifestations, treatments and outcomes in patients with IgG4-RD. Pulmonary involvement in IgG4-RD is relatively common, leading to high levels of morbidity and mortality. Glucocorticoids remain the mainstay of treatment, but further work is required to explore the management of patients with pulmonary manifestations in association with IgG4-RD.

Revealing the distinct clinical patterns and relapse risk factors in seronegative IgG4-RD patients: A retrospective cohort study over a decade

OBJECTIVES

Our study aimed to investigate the distinct clinical patterns of seronegative IgG4-related disease (IgG4-RD) patients.

METHODS

We retrospectively enrolled 698 treatment-naïve IgG4-RD patients in this study. Patients were divided into four different subgroups according to their baseline serum IgG4 levels. The distinct clinical patterns of seronegative IgG4-RD patients were revealed through the comparison of baseline clinical data and disease prognosis among the different subgroups. COX regression analyses were used to investigate the risk factors for disease relapse and to construct the nomogram model.

RESULTS

Seronegative IgG4-RD patients account for a minority of IgG4-RD patients (49/698, 7.02%). The proportions of seronegative IgG-RD patients in our study and several Asian cohorts were significantly lower than those of the European and American cohorts. Seronegative IgG4-RD patients got lower serum IgG levels (p < 0.0001), lower eosinophil count (p < 0.0001), lower serum IgE levels (p < 0.0001)), lower IgG4-RD responder index (RI) scores (p < 0.0001), and fewer affected organ numbers (p < 0.0001) compared with other subgroups, whereas they were more likely to manifest fibrotic type with some special organ involvement. Younger age at onset, GCs monotherapy, elevated C-reactive protein level, and elevated erythrocyte sedimentation rate level are the risk factors for the disease relapse of seronegative IgG4-RD patients. An effective nomogram model predicting disease relapse of seronegative IgG4-RD patients was constructed. Seronegative IgG4-RD patients with scores >84.65 at baseline were susceptible to suffering from disease relapse.

CONCLUSIONS

Distinct clinical features and multiple risk factors for disease relapse of seronegative IgG4-RD patients have been revealed in this study. A nomogram model was constructed to effectively predict disease relapse during the follow-up period.

Coronary periarteritis and pericarditis are rare but distinct manifestations of heart involvement in IgG4-related disease: a retrospective cohort study

BACKGROUND

The heart can be involved in immunoglobulin (Ig)-G4-related disease (IgG4-RD). This study aimed to summarize the clinical features and efficacy of treatment for IgG4-RD patients with heart involvement.

METHODS

We conducted a retrospective study enrolling 42 IgG4-RD patients with heart involvement from the IgG4-RD cohorts of the Peking Union Medical College Hospital and Beijing An Zhen Hospital, from 2010 to 2022. Clinical, laboratory, radiological data were collected, and treatment responses to glucocorticoids and immunosuppressants were analyzed.

RESULTS

IgG4-related cardiac involvement is a rare part of the IgG4-RD spectrum. The incidences of coronary periarteritis and pericarditis were 1.2%(13/1075) and 3.1%(33/1075), respectively in our cohort. Valvular disease possibly related to IgG4-RD was detected in two patients. None of the patients with myocardial involvement were identified. The average age was 58.2 ± 12.8 years, with a male predominance (76.7%). Coronary artery CT revealed that mass-like and diffuse wall-thickening lesions were the most frequently observed type of coronary periarteritis. Pericarditis presented as pericardial effusion, localized thickening, calcification and mass. After treatment with glucocorticoid and immunosuppressants, all patients achieved a reduced IgG4-RD responder index score and achieved radiological remission. Two patients with coronary peri-arteritis experienced clinical relapses during the maintenance period.

CONCLUSIONS

Cardiac involvement in IgG4-RD is rare and easily overlooked since many patients are asymptomatic, and the diagnosis relies on imaging. Patients showed a satisfactory response to glucocorticoid based treatment.

Immunoglobulin G4-related thoracic disease: clinical and radiological findings of a Turkish cohort

BACKGROUND AND AIM

Thoracic involvement of Immunoglobulin G4-related disease (IgG4-RD) is relatively rare and may be disregarded at the time of initial diagnosis due to its asymptomatic nature. This study aimed to ascertain the prevalence and patterns of thoracic involvement in a retrospective cohort of Turkish patients with IgG4-RD.

METHODS

A total of 90 patients (47 males and 43 females, with a mean age of 57.7±15.5 years) diagnosed with IgG4-RD were reviewed retrospectively. All computed tomography (CT) scans were re-evaluated by two thoracic radiologists and IgG4-related thoracic disease was assessed on four compartments: The mediastinum, pulmonary parenchyma, airways, and pleura. IgG4-related thoracic disease was categorized as: definite, highly probable, probable or possible.

RESULTS

There were 64 patients who had undergone at least one thorax CT examination, and 18 (28%) were diagnosed with IgG4-related thoracic disease. The rate of IgG4-related thoracic disease increased by 20% and reached a ratio of 48.4% (n=31) after a thorough reevaluation of registry data specifically to thoracic findings. The mediastinum was the most frequently involved compartment, affecting 16 (51.6%) patients, followed by pulmonary parenchyma in 14 (45.2%) patients, and airways and pleura in 10 (32.3%) patients each. Other organ involvements were more prevalent and IgG4 levels were higher in patients with thoracic involvement. Eosinophils were significantly elevated in patients with thoracic involvement (p=0.023).

CONCLUSIONS

IgG4-related thoracic disease is heterogeneous and likely to be more prevalent than currently recognized. The mediastinum is the most frequently involved compartment. It is important to assess IgG4-related thoracic disease at the time of initial diagnosis. Elevated levels of serum IgG4 and eosinophils, as well as a greater number of organ involvements may serve as indicators of thoracic involvement.

The development and initial validation of IgG4-related disease damage index: a consensus report from Chinese IgG4-RD Consortium

OBJECTIVE

To develop and conduct an initial validation of the Damage Index for IgG4-related disease (IgG4-RD DI).

METHODS

A draft of index items for assessing organ damages in patients with IgG4-RD was generated by experts from the Chinese IgG4-RD Consortium (CIC). The preliminary DI was refined using the Delphi method, and a final version was generated by consensus. 40 IgG4-RD cases representing four types of clinical scenarios were then selected, each with two time points of assessment for at least 3 years of follow-up. 48 rheumatologists from 35 hospitals nationwide were invited to evaluate organ damage using the CIC IgG4-RD DI. The intraclass correlation coefficient (ICC) and the Kendall-W coefficient of concordance (KW) were used to assess the inter-rater reliability. The criterion validity of IgG4-RD DI was tested by calculating the sensitivity and specificity of raters.

RESULTS

IgG4-RD DI is a cumulative index consisting of 14 domains of organ systems, including a total of 39 items. The IgG4-RD DI was capable of distinguishing stable and increased damage across the active disease subgroup and stable disease subgroup. In terms of scores at baseline and later observations by all raters, overall consistency in scores at baseline and later observations by all raters was satisfactory. ICC at the two time points was 0.69 and 0.70, and the KW was 0.74 and 0.73, respectively. In subgroup analysis, ICC and KW in all subgroups were over 0.55 and 0.61, respectively. The analysis of criterion validity showed a good performance with a sensitivity of 0.86 (95% CI 0.82 to 0.88), a specificity of 0.79 (95% CI 0.76 to 0.82) and an area under the curve of 0.88 (95% CI 0.85 to 0.91).

CONCLUSION

The IgG4-RD DI is a useful approach to analyse disease outcomes, and it has good operability and credibility. It is anticipated that the DI will become a useful tool for therapeutic trials and studies of prognosis in patients with IgG4-RD.

IgG4-related uveitis. A French cohort and literature review

INTRODUCTION

IgG4-related disease (IgG4-RD) is a fibro-inflammatory disorder that can affect almost any organ. IgG4-related ophthalmic disease is a protean condition involving the orbit and ocular adnexa. Although a few cases of uveitis have been reported, the exact pattern of IgG4-related intraocular manifestations remains unclear. Here, we report on a nationwide French multicenter cohort of patients with IgG4-RD and uveitis and conducted a literature review.

METHODS

Patients with uveitis and a concomitant definite diagnosis of IgG4-RD (Revised Comprehensive Diagnostic criteria, American College of Rheumatology/European League Against Rheumatism classification criteria for IgG4-RD, International Consensus Diagnostic Criteria for auto-immune pancreatitis, or diagnostic criteria for IgG4-related hypophysitis), were screened from our national IgG4-RD and systemic fibrosis database. Concomitantly, we conducted a PubMed literature review and selected cases of definite IgG4-RD with uveitis.

RESULTS

We reported on 16 patients (8 from our database and 8 from the literature) and a total of 30 episodes of uveitis. Uveitis cases represented 3 % of total IgG4-RD patients in the national database on IgG4-RD and systemic fibrosis. Uveitis was inaugural in IgG4-RD in 4/16 cases (25 %) (appearing before any other IgG4-related symptom, at a median of 9 months), occurred concurrently to other IgG4-related symptoms in 9/16 cases (56 %) (at a median of 15 months before IgG4-RD diagnosis), and appeared during follow up in 3/16 patients (19 %) (at a median of 57 months after first IgG4-related symptoms). When uveitis occurred during follow up, it was associated with IgG4-RD manifestations in other organs in 6/9 patients (67 %). Uveitis was bilateral in 8/16 cases (50 %) and granulomatous in 5/10 cases (50 %). It was anterior in 8/13 (62 %), intermediate in 3/13 (23 %), and global (panuveitis) in 4/13 patients (31 %). Median serum IgG4 at diagnosis was 3.2 g/L. Median follow up time was of 6 years, during which 8/16 patients (50 %) experienced at least one relapse of uveitis. Treatment data was available for 29/30 uveitis flares. Steroids were used in 28/29 episodes of uveitis (97 %), leading to remission of uveitis in 16/28 cases (57 %). Methotrexate and rituximab (in combination with systemic steroids) were administered as second- or third-line therapy in 6/29 (21 %) and 5/29 (17 %) episodes of uveitis, respectively, and led to remission of uveitis in 4/6 cases (67 %) and 4/5 cases (80 %), respectively. One third of uveitides required at least two different lines of treatment for remission induction (mainly a combination of both systemic steroids and methotrexate or rituximab).

DISCUSSION AND CONCLUSIONS

Uveitis may be one of the initial symptoms of IgG4-RD, and IgG4-RD should be considered in the diagnostic workup of uveitis. Its early onset in IgG4-RD may help with early diagnosis and treatment of the disease. Steroid monotherapy may be sufficient to treat IgG4-related uveitis, yet relapses were frequent (50 %) and ultimately a third of patients required at least two lines of treatment. Hence, steroid-sparing agents can be considered at early stages of the disease, particularly for patients with a high risk of relapse or steroid-related complications.

Update on respiratory lesions in patients with IgG4-related autoimmune pancreatitis

We previously reported respiratory involvement in 25 patients with autoimmune pancreatitis, a pancreatic manifestation of IgG4-related disease that responds well to glucocorticoid treatment. However, whether all respiratory lesions in patients with autoimmune pancreatitis have genuine respiratory involvement is unclear. This study aimed to update respiratory lesions' clinical and radiological characteristics in patients with autoimmune pancreatitis. We retrospectively reviewed the clinical and radiological data of 74 consecutive patients diagnosed with autoimmune pancreatitis at Shinshu University Hospital and treated with glucocorticoid. Clinical features and chest high-resolution computed tomography findings before and after therapy were reviewed. Fifty-one patients (68.9%) had respiratory lesions. In 65 of the 74 patients, chest high-resolution computed tomography results were evaluated before and after treatment. Patients with IgG4-related disease and respiratory lesions showed significantly higher serum IgG4 levels and hypocomplementemia than those without respiratory lesions; they also had more affected organs. While most abnormal thoracic findings improved, 4 cases of 7 with reticular opacities and all 11 cases with emphysema did not improve. Therefore, these lesions with poor response to glucocorticoid treatment should not be considered due to respiratory involvement of autoimmune pancreatitis based on the current classification criteria for IgG4-related disease. Patients with autoimmune pancreatitis and respiratory lesions exhibited higher disease activity than those without. Most chest high-resolution computed tomography lesions were responsive to glucocorticoid treatment, whereas reticular opacities and emphysema were poorly responsive.

Anatomic and Functional Imaging of Immunoglobulin G4-related Disease and Its Mimics

Immunoglobulin G4 (IgG4)-related disease (IgG4-RD) is an immune-mediated fibrosclerosing disease with tumefactive lesions infiltrated by IgG4-positive plasma cells. Initially described as autoimmune pancreatitis, IgG4-RD is now recognized as a discrete entity and is found to affect virtually any organ in the body. Common extrapancreatic sites include the biliary tree, salivary glands, periorbital tissue, lungs, kidneys, lymph nodes, aorta, retroperitoneum, and thyroid gland. Diagnosis-which relies on histopathologic, serologic, and radiologic features-can be challenging with the disease underdiagnosed, as IgG4-RD often mimics malignancy, infectious processes, or other immune-mediated conditions. Patients may present with signs of compression of nearby structures due to mass effect or with organ failure when the disease is left untreated. The clinical course is complex, with single- or multiorgan involvement and metachronous or synchronous occurrence of lesions. IgG4-RD responds well to glucocorticoid therapy, disease-modifying antirheumatic drugs, and B-cell-depleting biologic agents; prompt diagnosis is important to avoid delay in treatment and unnecessary pharmacologic or surgical intervention. While imaging features may not be specific for IgG4-RD, functional whole-body imaging with fluorine 18-fluorodeoxyglucose PET/CT is a useful adjunct for localizing extrapancreatic sites for biopsy, monitoring therapeutic response, and demonstrating disease relapse. The authors describe the pancreatic and extrapancreatic sites of involvement in IgG4-RD, with imaging features and patterns to aid in distinguishing IgG4-RD from its mimics through a multimodality approach with emphasis on functional imaging evaluation. ^©RSNA, 2023 Quiz questions in the supplemental material and the slide presentation from the RSNA Annual Meeting are available for this article.

Clinical characteristics of IgG4 with lung involvement in 14 patients

OBJECTIVES

Immunoglobulin G4-related diseases (IgG4-RD) is a rare autoimmune disease, and there is no specific diagnostic test for patients with lung involvement yet. This study aims to summarize the clinical characteristics of IgG4-RD with lung involvement and improve the understanding and diagnosis of this disease.

METHODS

All patients diagnosed with IgG4-RD in the Second Xiangya Hospital from December 2014 to February 2022 were re-diagnosed according to the recommendations of Chinese Expert Consensus on the Diagnosis and Treatment of IGG4-Related Diseases in 2021. The clinical data of 14 IgG4-RD patients with pulmonary abnormalities were collected and analyzed.

RESULTS

Among the 14 patients, 11 were males and 3 were females, and the median age of diagnosis was 66 (22-82) years old. Six cases had respiratory symptoms such as cough, sputum and short breath. Extrapulmonary involvement was the most common in the glands of head and neck (6/14), followed by pancreas and bile duct (4/14). Elevated serum IgG4 level was found in all patients, and most (11/14) were accompanied by abnormal inflammatory markers. Patients' pulmonary imaging findings were diverse, the most common performances were mediastinal/hilar lymphadenopathy (12/14), followed by multiple pulmonary nodules (9/14), patchy density enhancement (7/14) and the increased broncho vascular bundles (6/14). Lung biopsy was performed in 9 patients, their pathology results showed lymphoplasmic cell infiltration, 5 cases of them had interstitial fibrosis, 2 cases with phlebitis, and extrapulmonary biopsy was performed in 8 patients. Immunohistochemical results of all the patients showed that the number of IgG4+ plasma cells was more than 10 per high magnification, and the ratio of IgG4/IgG was more than 40%. For treatment, 12 patients received hormone therapy, and 5 patients combined immunosuppressive therapy with hormone. 10 patients were in remission after treatment, while 2 patients were progressed.

CONCLUSIONS

IgG4-RD with lung involvement is rare and has no specific clinical manifestation. Its pulmonary imaging is diverse. Diagnosis for it should combine with serum IgG4 level and pathological examination. Glucocorticoid is the first line treatment, and combination with immunosuppressant can help prevent disease recurrence.

Large lung mass lesion with spontaneous regression in a patient with IgG4-related lung disease

IgG4-related lung disease (IgG4-RLD) may present with a variety of radiological findings, but large lung mass lesion are rare. Although steroid therapy is strongly recommended for IgG4-RLD with or without symptoms, respirologists should be aware that some patients may not need steroid therapy.

Pulmonary IgG4-related disease with favourable response to rituximab: A case report

Pulmonary involvement of IgG4-associated disease is a rare condition with no codified treatment apart from steroid administration. We report here the case of a patient with pulmonary involvement of IgG4-RD successfully managed with Rituximab, in induction and maintenance therapy. This original case could support the use of Rituximab in rare situations of steroid-resistant or steroid-dependent pulmonary IgG4-RD.

IgG4 related lung disease mimicking multiple pleural disseminated lung cancer

IgG4-related lung disease (IgG4-RLD) can present with various types of radiological findings such as nodule, ground-glass opacity, alveolar interstitial, and bronchovascular involvement. IgG4-RLD generally manifests as mild clinical symptoms, despite evidence from the image findings. Herein we report an asymptomatic patient with IgG4-RLD mimicking multiple pleural disseminated lung cancer.