Immunoglobulin G4-related disease presenting with pulmonary manifestations, lymphadenopathy, and vocal cord immobility: an unusual presentation of a rare disease

Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated state, which includes a group of disorders that can affect nearly any organ. Pulmonary involvement can present with nonspecific signs, symptoms, and highly variable radiological picture. Recognition of the disorder mainly relies on histopathological findings and immunohistochemical staining. Serum IgG4 levels also help in diagnosis. Glucocorticoids are the first choice for treatment. As this condition mimics many infective, inflammatory, and malignant disorders, a comprehensive diagnostic workup is required before reaching the diagnosis. We report a case of IgG4-RD with pulmonary manifestations, lymphadenopathy, and vocal cord immobility.