抄録
Immunoglobulin G4 (IgG4) is thought to be involved in inflammatory IgG4-related disease pathology typically diagnosed clinically as Mikulicz’s disease or autoimmune pancreatitis. A recent proposal classifies IgG4-related disease as systemic, and we report a case believed to be IgG4-related disease.
A 76-year-old man was first seen on May 30, 2008, for submental swelling gradually developing since autumn 2007. Physical findings were a dry oral cavity, submental swelling and lymph node swelling. Magnetic resonance imaging (MRI) showed mediastinal lymph node hyperplasia and blood tests increased soluble IL-2 receptors, suggesting malignant lymphoma. Submaxillary gland biopsy on August 8, 2008, showed no clear malignant findings histopatholpgically, but noted chronic sialadenitis. IgG4 immune staining showed IgG4-positive plasmacytes infiltration and blood tests confirmed increased IgG4. Based on these findings, we diagnosed the case as IgG4-related disease, initiating oral prednisolone at 40 mg/day. Submaxillary gland swelling decreased significantly and soluble IL-2 receptors returned to normal. When MRI showed that submaxillary gland and lymph node swelling had been eliminated, prednisolone administration was gradually decreased.
Subjects with IgG4-related disease may have bilateral cervical lymph node swelling and increased soluble IL-2 receptor levels, and this case suggests the importance of considering IgG4-related disease in differential diagnosis.
