Immunoglobulin G4 Related Lung Disease.

Immunoglobulin G4 related disease (IgG4-RD) is a relatively newly defined disease known for multiple organ involvement. Histopathologically, the disease is characterized by lymphoplasmatic inflammation, fibrosis, and enhanced levels of IgG4-positive plasma cells in tissues. IgG4-RD has been reported in almost every organ system. With pulmonary involvement, lesions have been described in the lung parenchyma, airways, pleura, and the mediastinum. Glucocorticoids are the first choice of treatment, but additional immunosuppressive drugs may be administered in refractory patients. In this article, we report a patient with IgG4 syndrome who had lung parenchyma, mediastinum, aorta wall, and pancreatic involvement. Histopathological findings and high serum IgG4 level established the diagnosis of IgG4-related disease. The patient was treated successfully with glucocorticoids.