Juvenile systemic lupus erythematosus (jSLE) is a long-term, autoimmune condition, meaning that the immune system malfunctions and attacks the body's organs and tissues, especially the skin, joints, blood, kidneys and central nervous system. jSLE appears before the age of 18, though some healthcare professionals may also call it paediatric SLE or childhood-onset SLE. The term SLE is used on its own when it is diagnosed in people over the age of 18.
The name "systemic lupus erythematosus" dates back to the early 20th century. "Systemic" means that it affects many organs of the body. The word "lupus" is derived from the Latin word for "wolf" and it refers to the characteristic butterfly-like rash on the face, which is similar to the white markings on a wolf’s face. "Erythematosus" in Greek means "red" and it refers to the redness of the skin rash.
In Europe, around 1 in 2,500 people are diagnosed with SLE, and about 15% of all people with SLE are diagnosed before they are 18. Females of child-bearing years (15 to 45) are most often affected and, in that particular age group, the ratio of affected females to males is 9 to 1. Before puberty, the proportion of affected males is higher and about 1 of every 5 children with SLE is male.