Lung Involvement in IgG4-related Lymphoplasmacytic Vasculitis and Interstitial Fibrosis

There have been a few reports on lung diseases associated with an increased number of infiltrating IgG4-positive plasma cells or lung involvement of IgG4-related sclerosing disease, although their characteristic histologic features have not been well described. Herein, we present 3 cases of interstitial lung disease with common histology and abundant IgG4-positive cell infiltration. Patient 1, a 65-year-old man, was incidentally noted to have a...