Immunoglobulin G4-related disease mimicking asthma

Long-term clinical course and outcomes of immunoglobulin G4-related lung disease

Background

Immunoglobulin G4-related lung disease (IgG4-RLD) is the pulmonary manifestation of a systemic fibroinflammatory disease characterized by lymphoplasmacytic infiltration with an abundance of IgG4-positive plasma cells. Long-term clinical course and outcomes of IgG4-RLD remain unclear. We aimed to identify clinical characteristics, treatment outcomes, and longitudinal pulmonary function changes in patients with IgG4-RLD according to the radiologic classification.

Methods

Chest computed tomography findings of 37 subjects were classified into five subtypes: solid nodular, bronchovascular, alveolar interstitial, round ground glass opacity, and alveolar consolidative. Radiologic treatment outcomes and longitudinal pulmonary function changes were compared among the different radiologic subtypes.

Results

The mean age of the subjects was 55.6 years, and 78.4% were male. Among the five radiologic subtypes, alveolar consolidative and solid nodular type were most common, accounting for approximately 29.7% each of the total cases. Prednisone with or without azathioprine was administered to 31 patients (median treatment duration 14 months). In the treated patients, serial images showed complete response or partial response in 77.4%. However, relapse was documented in 25.0% of those who showed complete or partial response. In patients whose longitudinal lung function data were available (n = 20), the lung function was found to be stable during follow-up. Alveolar consolidative type showed the highest complete response rate, whereas alveolar interstitial type showed the lowest response rate, either complete or partial.

Conclusions

Most patients showed a favorable outcome with regards to radiologic improvement and maintenance of pulmonary function; however, the response differed according to the radiologic subtype.

Multi-organ IgG4-related disease continues to mislead clinicians: A case report and literature review

BACKGROUND

Immunoglobulin G4-related disease (IgG4-RD) is a multisystemic mass forming immune-mediated disease that affects almost every organ and is a diagnostic challenge for every clinician. There is a lack of adequate epidemiological data worldwide, and evidence-based treatment recommendations are not yet established. We report the first case of IgG4-RD from Lithuania and the Baltic Sea region presented with thyroiditis, orbital myositis, orbitopathy, uveitis, scleritis, sialadenitis, autoimmune pancreatitis and prostatitis.

CASE SUMMARY

A 54-year-old Caucasian male was admitted to our tertiary Centre complaining of severe weight loss, diarrhoea, abdominal pain, salivary gland swelling, sicca symptoms and diplopia. On examination, bilateral palpable masses in the projection of major salivary glands, severe protrusion of the left eyeball and cachexia were noted. The patient was previously diagnosed with autoimmune thyroiditis and endocrine ophthalmopathy. The magnetic resonance imaging (MRI) of the head revealed enlarged extraocular muscles indicating orbital myositis. The biopsy from the salivary gland mass indicated sialadenitis. Abdominal MRI showed signs of autoimmune pancreatitis, and a serological test revealed the elevated serum IgG4 concentration. The patient was then diagnosed with IgG4-RD and successfully treated with prednisolone. There was a significant clinical, serological and radiological improvement after one month of treatment and no signs of relapse within twenty months. However, it took almost 18 years and the efforts of eight different medical specialists to establish the correct diagnosis.

CONCLUSION

A comprehensive approach to the patient is essential to improving the recognition of rare immune system conditions, such as IgG4-RD.

IgG4-related disease with tracheobronchial miliary nodules and asthma: a case report and review of the literature

Background

IgG4-related disease (IgG4-RD) is a systemic autoimmune disease that can affect multiple organs of the body. Pulmonary manifestations of IgG4-RD include pulmonary solid nodules, thickening of bronchovascular bundles, interstitial involvement, and ground glass opacities. Here we present a rare case of IgG4-RD with tracheobronchial nodules and review the relevant literature.

Case presentation

A 52-year-old man was admitted to our hospital with a history of intermittent cough for 27 months and recurrent wheezing for 17 months. He had been diagnosed with asthma prior to admission and was responsive to oral prednisone (30 mg/day, with gradual tapering). Bronchoscopy performed 2 years prior to admission showed tracheal and bronchial mucosal hyperemia, edema, and miliary nodules. Pathological tests showed chronic inflammation with focal lymphocytic infiltration in the bronchial mucosa. The patient had recurrent cough and wheezing after prednisone was stopped or the dose reduced. At the time of admission to our hospital, his serum immunoglobulin G4 (IgG4) level had increased to 7.35 g/L. Following bronchoscopy, the IgG4 expression in the bronchial mucosa was compared with that observed during the last two bronchoscopies. Bronchoscopy performed 7 months prior to admission revealed IgG4+ plasma cell infiltration in the bronchial tissue, with > 10 IgG4+ plasma cells per high power field and an IgG4+/IgG+ cell ratio of > 40%. The current bronchoscopy revealed a decrease in IgG4 expression in the bronchial tissue, probably because of the intermittent prednisone treatment. The case fulfilled the comprehensive clinical diagnostic criteria for IgG4-RD. He received prednisone and azathioprine, and he has never developed recurrence.

Conclusions

Our case exhibited three important clinical indication: First, tracheobronchial miliary nodules could be the presentation of IgG4-related disease. Second, IgG4-related disease with pulmonary involvement has close connection with asthma. Last, IgG4-related disease can be very sensitive to prednisone, the infiltration of IgG4 positive plasma cells decreased after prednisone treatment and symptoms significantly improved in our case. In conclusion, we reported the first case of IgG4-RD presenting with miliary nodules on the tracheal and bronchial tube walls combined with asthma. The findings will further our understanding of the characteristics of IgG4-RD.

An update on IgG4-related lung disease

IgG4-related disease (IgG4-RD) is an autoimmune disorder characterized by substantial infiltration of plasma cells with IgG4 in target organs. Lung manifestations predominantly present as inflammatory pseudotumor, interstitial pneumonitis, organizing pneumonia, and lymphomatoid granulomatosis. There is no specific diagnostic test for IgG4-related lung disease (IgG4-RLD), and excluding diseases that mimic IgG4-RLD is important. Corticosteroids with or without disease-modifying anti-rheumatic drugs are recommended for treatment. The long-term prognosis of IgG4-RLD remains unknown. In this review, we summarized the current diagnostic algorithms and discussed potential biomarkers for future investigation.

IgG4-related respiratory disease

IgG4-related diseases (IgG4-RDs), such as autoimmune pancreatitis and IgG4-related Mikulicz disease, are often accompanied by intrathoracic lesions, which are called IgG4-related respiratory disease (IgG4-RRD). IgG4-RRD has few subjective symptoms, and is usually detected during workup of patients with extra-thoracic lesions of IgG4-RD. IgG4-RRD is characterized by various conditions, including masses, nodules, thickening, and infiltration at numerous sites in the thorax through lymphatic routes. Although elevated serum IgG4 concentrations and pathologic evidence of lymphoplasmacytic infiltrates with abundant IgG4-positive plasma cells are characteristic findings of IgG4-RD, other intrathoracic diseases, such as multicentric Castleman disease and malignancy, may present with similar findings. Developing diagnostic criteria for IgG4-RRD, including clinicoradiological and pathological characteristics, is necessary for its appropriate diagnosis.

IgG4-related lung disease on the horizon

Immunoglobulin G4 (IgG4) related lung disease is an emerging entity. We report a case of a 42-year-old man presented with fever and cough with minimal sputum. Chest X-ray revealed diffuse reticulonodular shadows. Extensive investigations were performed, including video-assisted thoracoscopic lung biopsy, which confirmed the diagnosis of IgG4-related disease (IgG4-RD) with lung involvement. This case report aims to illustrate that IgG4-related lung involvement can present as diffuse lung nodules and can affect different pulmonary structures. IgG4-RD should always be considered when a similar scenario is encountered.

Immunoglobulin G4-related acquired hemophilia: A case report

Acquired hemophilia A (AHA) is a relatively rare and life-threatening bleeding disorder whose pathogenesis is not completely understood. The present study reports a rare case of immunogubulin (IgG)4-related AHA with multisystemic involvement. A 55-year old male patient presented with symptoms of bronchial asthma and multiple subdermal hematomas. Chest computed tomography showed multiple diffuse nodular lesions with thickening of bronchovascular bundles, and scattered high-density spots in both lung lobes. Laboratory investigations showed increased activated partial prothrombin time (120.0 sec), a markedly decreased factor VIII (FVIII) activity (0.5%), a high-titer of FVIII inhibitor (27.2 Bethesda units/ml) and a marked increase in serum IgG4 (>4.03 g/l) level. Left inguinal lymph node biopsy revealed capsular thickening with marked lymphoplasmacytic infiltration, occlusive phlebitis and irregular fibrosis. Immunostaining revealed numerous IgG4-positive plasma cells (>100 cells/human plasma fibronectin) in the nodular lesions, with an IgG4/IgG ratio of >40%. The symptoms were markedly alleviated following corticosteroid therapy. The current study presents the first reported case of a rare IgG4-related AHA that presented with unusual clinical features and multisystemic involvement. The patient responded well to corticosteroid therapy. Documentation of such rare cases will help in characterizing the pathogenesis, and prompt recognition and timely treatment of this rare disorder.

What are the characteristics of asthma patients with elevated serum IgG4 levels?

INTRODUCTION

IgG4 has recently been a subject of great interest in human pathology. No data are available about the characteristics of asthma patients with elevated IgG4 levels.

POPULATION AND METHODS

An observational study was conducted from January 2006 to March 2015 in a difficult-to-treat population of asthma patients. Twenty-six difficult-to-treat asthma patients with elevated serum IgG4 levels (IgG4/IgG ratio up to 10%) were compared with a control population of 98 difficult-to-treat asthma patients with normal serum IgG4. Blood eosinophilia, total IgE and FeNO were compared between groups to better characterize asthma patients with elevated serum IgG4 levels.

RESULTS

Median IgG4 concentrations were 1.72 g/l [1.19-2.36] and 0.22 g/l [0.10-0.49] in the elevated IgG4 group and normal Ig4 group, respectively. Median blood eosinophilia was more than three times higher in patients with elevated serum IgG4 levels than in controls (0.75 10(9)/L [IQR 0.54-1.78] vs 0.22 10(9)/L [IQR 0.09-0.54] respectively, p < 0.0001). Total IgE was twice as high (264.5 kUI/l [IQR 166.3-779] vs 126 kUI/l [IQR 26-350] respectively; p < 0.05) and FeNO was nearly twice as high (61 [IQR 41-111] ppb vs 35 [IQR 23-51] ppb, p < 0.001). Allergic broncho-pulmonary aspergillosis (ABPA) and eosinophilic granulomatosis with polyangiitis (EGPA) were observed in the asthma patients with elevated serum IgG4. Ten patients had unexplained increased blood eosinophilia.

CONCLUSION

Asthma patients with elevated IgG4 levels have significantly higher blood eosinophilia, total IgE and FeNO. ABPA and EGPA are observed in patients with elevated serum IgG4.

IgG4-related Lung Disease Associated with Autoimmune Hemolytic Anemia: A Case Report and a Literature Review

We herein report a case of IgG4-related lung disease (IgG4-RLD) associated with autoimmune hemolytic anemia (AIHA). A 73-year-old Japanese female visited our hospital for an examination following an abnormal chest X-ray in 1999. She was diagnosed with bronchiolitis and AIHA, and treatment with prednisolone was started. After seven years, she visited our department due to a cough. Chest computed tomography (CT) demonstrated focal consolidation with ground-glass attenuations and thickened bronchial walls in the bilateral lungs. She was clinically diagnosed and treated for bronchial asthma. CT findings had shown no changes, and a lung biopsy was performed using video-assisted thoracic surgery at eleven years from the first diagnosis of AIHA. The pathological findings demonstrated the presence of peribronchovascular lymphoplasmacytic infiltrates with stromal fibrotic changes, admixed with many IgG4-positive plasma cells. Furthermore, the patient's serum IgG4 level was high, and her CT findings did not show any obvious abnormal findings in the any organs other than the lungs. She was diagnosed with IgG4-RLD based on the findings. We believe that this case report of IgG4-RLD associated with AIHA is clinically helpful for a better understanding of these diseases, although there are five reported cases of IgG4-related disease associated with AIHA.

Clinical review of pulmonary manifestations of IgG4-related disease

IgG4-related disease (IgG4-RD) is a recently recognized systemic disease characterized by tumefactive lesions in various organ systems. The list of organs that can be involved continues to expand, and recently computed tomography (CT) descriptions of the pulmonary lesions found in the disease have been described. The clinical symptoms are nonspecific and may include cough, dyspnea, chest pain, and fever. The appropriate clinical presentation along with elevated serum IgG4 concentrations and pathologic evidence of lymphoplasmacytic infiltrates with abundant IgG4-positive plasma cells and storiform fibrosis is consistent with the disease. Steroids are used to treat this disease in addition to immunosupressives such as cyclosporine or rituxumab for steroid refractory disease. The pulmonary manifestations and imaging features can often mimic malignancy, and as such knowledge of the diagnostic, clinicopathologic, and radiographic features of the disease is required in order to provide appropriate diagnostic workup and treatment.