Immunoglobulin G4-related disease (IgG4-RD) is a new disease entity recognized at the start of this century noted to be involving many organ systems including endocrine system and thyroid in particular. It represents an immune mediated fibro inflammatory condition with characteristic histopathological appearance affecting single or multiple organs. In general, immunoglobulin G4-related thyroid disease (IgG4-RTD) is rarely considered and it may be isolated or with other organ involvement. Four subcategories of IgG4-RTD have been identified so far: Riedel thyroiditis, fibrosing variant of Hashimoto thyroiditis, immunoglobulin G4-related Hashimoto thyroiditis, and Graves disease with elevated immunoglobulin G4 levels. The diagnostic approach is complex and the work up relies on the coexistence of clinical features, histological features and serological evidence. Demonstration of the classic histopathological features is vital to diagnose IgG4-RD in most cases, and biopsy proof is preferred strongly by most disease experts before the initiation of treatment. The treatments for IgG4-RTD include medical and surgical options. Steroids are first line treatment though it may need further evaluation. Tamoxifen and rituximab are second line treatment for steroid resistant patients. Surgical excision of thyroid gland in presence of compression symptoms is the surgical option. Inspite of pathophysiology of the disease being poorly understood till now, early and prompt diagnosis and an early treatment initiation can improve the outcomes.

Citation： John Jobin, Nanwei TONG. Immunoglobulin G4-related thyroid diseases. West China Medical Journal, 2018, 33(5): 584-588. doi: 10.7507/1002-0179.201803160 Copy