Natural History of Coronavirus Disease (COVID-19) in Systemic Autoimmune Diseases

Background: Viral infections such as COVID-19 may lead to flare-ups in people with systemic autoimmune diseases (SAD). These infections may also change the function of their immune system and/or cause problems with their blood vessels. Researchers want to learn how people with SAD respond to treatments or vaccines for COVID-19. Objective: To understand how COVID-19 affects inflammation, the immune system, and blood vessels in adults and children with autoimmune diseases. Eligibility: People ages 15 and older who have been diagnosed with an autoimmune disease or are a healthy volunteer Design: Participants will have a screening visit. This will include: Medical history and physical exam EKG Chest x-ray COVID-19 test. A swab will be put in the participant s nose or the back of their mouth. Blood and urine tests Participants will be placed into 1 of 4 groups: 1. Those with previously documented COVID-19 infection or COVID vaccination 2. Those with a recently known COVID-19 exposure or vaccination 3. Those with no known COVID-19 exposure or vaccination 4. Those who developed an acute COVID-19 infection Depending on their group, participants will have 1 to 5 more visits. These will occur over 12 to 18 months. Visits may include: FDG PET/CT scan. Participants will lie in a doughnut-shaped machine. The machine creates pictures of the body. For the scan, they will have a radioactive substance injected into their arm through an IV. Kidney function tests Non-invasive vascular studies test. These tests are similar to what it feels like to have blood pressure checked.