ANA and anti-DNA are important in diagnosing SLE because their presence in significant titer documents abnormal immune system activation. The damage results from organ specific reactions to the excessive deposition of immune complexes. Systemic lupus erythematosus remains uncommon. Over the age of ten years, SLE becomes much more common among girls because of the 'synergistic' effect of female sex hormones. However a significant number of boys are included in every series.
Race is also a significant risk factor.
The most common manifestations of SLE in childhood are nonspecific and consistent with diverse diagnoses. A variety of findings in the initial work-up of a child with chronic illness should alert the physician to the possibility of SLE . ANA testing is a useful screen for SLE . Widespread arthritis of the small joints of the hands and feet on careful examination is a useful finding that suggests SLE . Small effusions of the knee joints are also commonly present with active disease.