musculoskeletal and connective tissue disorders
IgG4 Related Disease
Key Points
IgG4-related disease (IgG4-RD) is a chronic, immune-mediated disorder that often manifests with multiorgan involvement and tumor-like masses most often affecting the pancreas, bile ducts, lacrimal glands, orbital tissues, salivary glands, lungs, kidneys, retroperitoneal tissues, aorta, meninges, and thyroid gland. IgG4-RD does not cause fever and typically manifests insidiously. Serum IgG4 levels are usually elevated, but this finding is neither highly sensitive nor specific. Diagnosis is most often based on a combination of clinical, radiologic, histopathologic, and immunostaining findings with emphasis on tissue sampling. Treatment includes corticosteroids and oftenrituximab. 