Background:
Inflammatory conditions can cause symptoms like fevers, arthritis, and rash. Systemic juvenile idiopathic arthritis (sJIA) is one of these conditions. So is adult-onset Still s disease (AOSD). Their causes are unknown. Researchers want to learn more about these conditions. This includes genetic changes and environmental factors.
Objective:
To study sJIA and AOSD in children and adults over time.
Eligibility:
People with known or suspected sJIA, AOSD, or similar inflammatory condition
Design:
Participants will be screened with a phone call.
Participants will have 1 visit. It may be outpatient or they may be admitted to the clinic. The visit may last up to 5 days. Participants will have:
* Medical history * Physical exam * Musculoskeletal exam * Questions about overall health and quality of life, disease activity, functional status, and cognitive ability.
Participants may also have:
* Pictures taken of their skin, joints, or spine * Blood, urine, and stool tests * Scans or X-rays of joints with arthritis * Chest X-ray * Heart tests * Skin biopsy. The skin will be numbed. The top layers of a small area will be scraped off.
Participants who have a joint aspiration may provide a fluid sample. The joint will be prepared, then fluid is removed by needle. A corticosteroid may be injected.
Participants who have a bone marrow biopsy may provide sample cells.
Participants may be seen by NIH specialists.
Members of the participant s family and healthy volunteers may give blood or saliva samples for genetic testing.
Participants may repeat some study tests every 6 months.
None
Patients less than 16 years of age will be considered to have sJIA if they meet the ILAR criteria for sJIA.
Patients 16 years of age and older will be considered to have sJIA if they have previously met ILAR criteria for sJIA.
Family members of individuals included under items 1 and 2.
Controls for clinical, cellular, molecular, and biochemical assays, and genetic evaluation will be enrolled. Individuals who undergo phlebotomy specifically to provide a control specimen will include both pediatric and adult patients and will not be pregnant.