[SLE: Extra-renal clinical manifestations and lupus nephritis].
Systemic Lupus Erythematosus (SLE) is a chronic inflammatory autoimmune disease affecting multiple organ systems, skin and joints the most involved. Lupus Nephritis occurs in Approximately 50% of patients, sometimes it may be the first manifestation of SLE. Clinical features range from asymptomatic urinary abnormalities to full-blown nephrotic syndrome or rapidly progressive renal failure. Because of the heterogeneity of clinical renal manifestations, renal biopsy plays an important role in the management of patients with SLE: it provides information about the class, severity, activity and chronicity of the renal disease that cannot be accurately predicted on the basis of clinical parameters. The complexity of protean renal manifestation of SLE can be approached using the original WHO classification (1982), recently revised (2004).