Immunoglobulin G4-related disease (IgG4-RD) is a recently defined emerging clinical entity characterized by tissue infiltration by IgG4-positive plasma cells, tissue fibrosclerosis and elevated serum IgG4 concentration. The most important feature of IgG4-RD is chronic inflammation with multiple organ involvement. However, some organ involvements are difficult to find by ultrasound, CT or MRI.~18F-FDG PET/CT is a sensitive imaging tool for inflammation. In this study, PET/CT were performed in patients with IgG4-RD both before and after glucocorticoid treatment by a single dose of 18F-FDG. Visual and semiquantitative method will be employed to assess the PET/CT images. The PET/CT image data will be used to establish a diagnostic model as well as assessment criteria for response evaluation of IgG4-RD treatments.
This is an open-label study to investigate the diagnostic performance of 18F-FDG PET/CT (positron emission tomography/computed tomography) in evaluation of patients with IgG4-related disease. A single dose of 18F-FDG will be intravenously injected into patients with IgG4-related disease before and after treatment.