Case Of IgG4-related Lung Disease Research Articles

IgG4-related lung disease with recurrent pulmonary lesions during steroid therapy and difficulty in differentiating from malignancy: a case report

BackgroundImmunoglobulin G4-related disease (IgG4-RD) is characterized by the formation of inflammatory lesions with fibrosis and infiltration of IgG4-positive plasma cells and lymphocytes in various organs of the body. Since the first report of IgG4-related autoimmune pancreatitis, IgG4-RD affecting various organs has been reported; however, only a few reports of IgG4-related lung disease (IgG4-RLD) exist. In this report, we describe a case of IgG4-RLD that was difficult to differentiate from malignancy, and the usefulness of the surgical approach in determining the appropriate diagnosis and treatment plan.Case presentationA 61-year-old man was referred to our hospital after a chest radiograph revealed an abnormal chest shadow. At the time of his first visit, he had a slight fever and dyspnea on exertion. Chest computed tomography (CT) revealed a middle lobe hilar mass with irregular margins and swelling of the right hilar and mediastinal lymph nodes. These findings were not present on CT 1.5 years ago. 18F-fluorodeoxyglucose-positron emission tomography revealed a mass lesion with a maximum diameter of 5.5 cm, maximum standardized uptake value (SUVmax) of 11.0, and areas with high SUV in the hilar and mediastinal lymph nodes. We suspected lung cancer or malignant lymphoma and performed a thoracoscopic lung biopsy to confirm the diagnosis. Histopathological examination revealed no malignant findings, and IgG4-RLD was diagnosed. One month after treatment with prednisolone (PSL), the tumor had shrunk, but a CT scan during the third month of PSL treatment revealed multiple nodular shadows in both lungs. Considering the possibility of malignant complications and multiple lung metastases, we performed thoracoscopic partial lung resection of the new left lung nodules to determine the treatment strategy. Histopathological examination revealed no malignant findings in any of the lesions, and the patient was diagnosed with IgG4-RLD refractory to PSL monotherapy.ConclusionsIgG4-RLD refractory to PSL monotherapy showed changes from a solitary large mass (pseudotumor) to multiple nodules on chest CT. It was difficult to distinguish malignancy from IgG4-RLD based on imaging tests and blood samples alone, and the surgical approach was useful in determining the appropriate diagnosis and treatment plan.

Thoracoscopic resection for a pulmonary nodule with the infiltrate of IgG4‐positive plasma cells

This report describes a rare case of IgG4-related lung disease that was difficult to distinguish from lung cancer. CT revealed a well-demarcated round tumor in S10 of the right lung of a 56-year-old man suspected of having lung cancer. PET revealed high fluorodeoxyglucose uptake with a maximum standardized uptake value of 14.0. Because primary lung cancer was strongly suspected, lower lobectomy was performed via the thoracoscopic approach without mini-thoracotomy. Histopathology showed lymphoplasmacytic infiltration. Immunostaining revealed numerous IgG4-positive plasma cells diffusely infiltrating the tumor. Serum IgG4 levels increased, thereby confirming the diagnosis of IgG4-related lung disease.

A Case of IgG4-related Lung Disease Associated with Multicentric Castleman's Disease and Lung Cancer

A 67-year-old man with submaxillary lymphadenopathy diagnosed as reactive follicular hyperplasia of the lymph node was referred to us for pulmonary evaluation. Pathological findings of the lung and hilar lymph node biopsies showed the histological feature of Castleman's disease (CD). Interestingly, infiltrated plasma cells had strong immunoreactivity for IgG4. In addition, this patient had coexisting lung cancer. We believe this is the first described case of IgG4-related lung disease associated with multicentric CD (MCD) and lung cancer. To establish a therapeutic strategy for IgG4-related lung disease, the association between IgG4-related disease and MCD needs to be clarified.

A Case of IgG4-related Lung Disease with Multiple Infiltrative Shadows, Mediastinal Lymphadenopathy and Left Endobronchial Tumor

A Case of IgG4-related Lung Disease with Multiple Infiltrative Shadows, Mediastinal Lymphadenopathy and Left Endobronchial Tumor

IgG4-related Lung Disease in a Worker Occupationally Exposed to Asbestos

A case of IgG4-related lung disease in a worker who had been exposed to asbestos is described. The patient had nocturnal cough and wheeze that responded to inhaled corticosteroid, and the radioallergosorbent test was positive against common allergens, suggesting an association with atopic asthma. IgE elevation is reported in asbestos-exposed workers, and asbestos exposure may cause atopic conditions. Predominance of Th2 cytokines and up-regulation of regulatory T lymphocytes have been reported in IgG4-related disease. IgG4-related disease may occur from hypersensitivity of the regulatory immune system to atopic conditions. Asbestos exposure may be a causal factor of IgG4-related disease.