Polyarticular Juvenile Idiopathic Arthritis

Juvenile Idiopathic Arthritis (JIA) is a chronic condition that causes joint inflammation in children. In some cases, the inflammation also affects the protective sheath surrounding the tendons, a condition known as tenosynovitis. Because tenosynovitis can be difficult to distinguish from regular joint swelling during a standard physical exam, specialized imaging tools like ultrasound are highly useful for an accurate diagnosis. This observational study aims to determine how frequently tenosynovitis occurs in children and adolescents diagnosed with two specific subtypes of the disease: polyarticular and oligoarticular JIA. Researchers will evaluate participants up to 16 years of age receiving care at Assiut University Children Hospital. During the study, patients will undergo a standard clinical assessment, which includes a medical history review and a thorough physical examination of their joints and tendons. Routine laboratory blood tests will also be reviewed. To precisely detect any hidden tendon inflammation, doctors will perform a musculoskeletal ultrasound, which is a safe, radiation-free imaging procedure, on major tendon and joint sites. By comparing the clinical exams with the ultrasound findings, researchers hope to improve the early recognition and management of tendon inflammation in pediatric JIA patients.

This study is to assess the safety and effectiveness of Xeljanz in Juvenile Idiopathic Arthritis (JIA) patients in routine clinical practice in Korea. JIA patients experience persistent joint pain, swelling and stiffness. This is a prospective observational study. Xeljanz is a JAK inhibitor. It was first approved in 2014 for rheumatoid arthritis patients in Korea. The ministry of Food and Drug Safety in Korea mandates for a drug manufacturer to report the post-marketing surveillance after drug's approval or indication extension. This study is to see the safety and effectiveness of Xeljanz in Juvenile Idiopathic Arthritis patients in routine clinical practice in Korea. This study is seeking patients who: * Are 2 to less than 18 years of age; * Are given Xeljanz for the treatment of JIA. The study sponsor will monitor patients' treatment experience for up to 44 weeks. This will help assess the safety and effects of this study medicine.

This is an investigator-initiated trial to evaluate the efficacy and safety of BCMA/CD70-targeted CAR-T in the treatment of refractory pediatric rheumatic diseases.