ig4

ig4 refers to immunoglobulin G4 (IgG4) related disease, a chronic, fibrosing inflammatory condition that can affect virtually any organ. It is characterized by a tissue-specific chronic inflammation and fibrosis, leading to the formation of tumor-like masses or diffuse enlargement of affected organs. The precise cause of IgG4-related disease is not fully understood, but it is believed to involve an abnormal immune response. A hallmark of the disease is elevated serum IgG4 levels and the presence of IgG4-positive plasma cells in affected tissues. However, elevated IgG4 alone is not diagnostic, and a combination of clinical, serological, and histopathological findings is required for diagnosis. Symptoms vary widely depending on the organs involved, which can include the pancreas, bile ducts, salivary glands, orbits, kidneys, lungs, and aorta. Common manifestations can include painless swelling of salivary or lacrimal glands, jaundice, abdominal pain, and organ dysfunction. Treatment typically involves corticosteroids, which are often effective in inducing remission and reducing inflammation. In some cases, steroid-sparing agents may be used.