Systemic lupus erythematosus in identical twins: a case report.

In this report we describe the case of identical twin sisters that developed systemic lupus erythematosus (SLE). These patients have in common major histocompatibility complex class I and class II alleles and identical red blood cell antigens, which is a clear indication of monozygotic twins. Both twins showed high titers of anti-dsDNA antibody.