Abstract
Juvenile idiopathic arthritis (JIA) is a chronic arthritis of unknown cause that develops in patients younger than 16 years of age and persists for at least 6 weeks. It is an important cause of short- and long-term physical and mental impairments in children. The goal of treatment for JIA is remission. A T2T (treatment-to-target) has been proposed and practiced as a means of achieving remission. The method of evaluating the disease activity of JIA depends on the disease type. For systemic JIA, disease activity is determined by comprehensively considering joint findings, systemic inflammatory findings, changes in inflammatory and synovitis markers, imaging findings, and other factors. For articular JIA other than systemic JIA, the Juvenile Arthritis Disease Activity Score (JADAS-27) is used to evaluate disease activity. The CHAQ (Childhood Health Assessment Questionnaire) and the Japanese version of the modified Rankin Scale (mRS) are mainly used to assess the physical function and ADL. The CHAQ is a global standard assessment method with the advantage that it can be transitioned to the HAQ used in adults, making it useful for international comparisons. The mRS is used to classify the severity of JIA as a chronic disease, and is an indispensable evaluation method in the specific disease procedure in Japan. It is necessary to have pediatric-specific knowledge of growth and development and routine childhood immunizations and to consider transition support tailored to the patient's situation. Ultimately, the goal is to foster the patient's independence and to provide an uninterrupted follow-up in the adult care department. Continuous follow-up will be provided during the schooling (and later, employment) period, and the relationship with the patient will be tailored to their developmental stage. It is also important to understand and communicate the importance of contraception and the drugs that cannot be used during pregnancy.