[A case of IgG4-related disease with marked thickening of the bronchial wall].

A 52-year-old man noticed hardening and swelling of his salivary glands in the summer of 2009. We suspected Mikulicz disease and performed several work-ups. His serum IgG4 level was elevated, and a chest computed tomography scan demonstrated marked thickening of the bronchial wall. A histopathologic examination of a bronchial mucosa biopsy specimen revealed diffuse infiltration of IgG4-positive cells in the submucosal layers, and on this basis we diagnosed IgG4-related disease. After the administration of corticosteroids, the patient's symptoms, his serum IgG4 level and bronchial wall thickening all improved. When encountering a patient with thickening of the bronchial wall, IgG4-related disease should be considered.