Maintenance Therapy for Lupus Nephritis — Something Old, Something New

From a historical perspective, there are few diseases for which the cause, natural history, and response to treatment have been as complex or difficult to define as those of systemic lupus erythematosus (SLE). In large part, this is because SLE represents a clinical syndrome rather than a unique disease entity. The apparent diversity of pathogenic mechanisms operating in individual patients, which parallels the diversity observed in various animal models of SLE, underscores the fact that the disease phenotype arises from a variable mixture of environmental factors, the hormonal milieu, genes that contribute to an autoimmune diathesis, and other causes of . . .