[Neonatal lupus syndrome]

Neonatal lupus syndrome is a passively acquired autoimmune syndrome in which pathogenic autoantibodies (anti-SSA/Ro, anti-SSB/La, and both, or rarely anti-U(1)RNP antibodies) are transmitted from a mother to her fetus through the placenta. The major clinical manifestations in the infants are cardiac (congenital heart block), dermatologic (skin lesion), hepatic (elevated hepatic enzymes), and hematologic (cytopenia). Congenital complete heart block (CCHB) is irreversible, while noncardiac manifestations are transient, resolving by one-year-old of age without specific treatments. Two prospective studies show that the prevalence of CCHB in children from a woman previously known to have anti-SSA/Ro antibodies is approximately 2%. However, when the previous pregnancy is complicated by CCHB and skin lesion, the recurrence rates of these symptoms go much higher to 10.5% and 26%, respectively, in the subsequent pregnancy.