Two Cases of Pulmonary Involvement of Immunoglobulin G4 Related Autoimmune Disease / 결핵및호흡기질환

ABSTRACT

Immunoglobulin G4 (IgG4) related autoimmune diseases are characterized by high serum IgG4 concentrations, sclerosing inflammation of numerous IgG4-positive lymphoplasma cells of varying origin, and a positive response to steroid treatment. Autoimmune pancreatitis, sclerosing cholangitis, and retroperitoneal fibrosis are representative presentations of IgG4 related autoimmune disease. Herein, we describe 2 patients (40-years-old woman and 47-years-old man) diagnosed with pulmonary involvement of IgG4-related autoimmune disease. The patients were admitted for an evaluation of the lung mass or multiple lung nodules found on chest radiography. Surgical lung biopsies were performed and pathologic finding revealed lymphoplasmacytic sclerosing inflammation with numerous IgG4 positive cells. The patients had elevated serum total IgG and IgG4 levels. Treatment consisted of high dose methylpredinisolone (1 mg/kg/day) and demonstrated good responsiveness. However, one patient experienced 2 relapses while being tapered off of steroid treatment.