Abstract
Juvenile primary fibromyalgia syndrome (JPFS) is a chronic, musculoskeletal pain syndrome affecting children and adolescents, most commonly adolescent girls. The syndrome has a multifactorial etiology, with altered central pain processing playing an important role. The hallmark symptom is severe, widespread musculoskeletal pain. Other symptoms include sleep and mood disturbances, headaches, stiffness, and subjective joint swelling. Physical examination can reveal multiple tender points. The diagnosis is clinical, with defined criteria. Early diagnosis and intervention are important. In this part of the review, we discuss the epidemiology, etiology, pathogenesis, clinical manifestations and diagnosis of JPFS. Part two will focus on treatment and prognosis.