Immunogenetics of the Neonatal Lupus Syndrome

Abstract

Neonatal lupus erythematosus is a disease of infants characterized by congenital heart block, transient cutaneous lesions, or both. The syndrome is related to the passage of maternal autoantibodies across the placenta to the fetus, and its resolution usually occurs within 6 months, when the infant becomes seronegative. The autoantibody associated with neonatal lupus is anti-SSA/Ro. Mothers of infants with the disease may have Sjögren's syndrome or systemic lupus erythematosus, but they are often asymptomatic. Fewer than 100 cases of neonatal lupus have been reported, which probably underestimates the prevalence of the disease. It is important to recognize the syndrome because newborns may develop complete heart block with congestive heart failure and residual scarring or pigment changes of the skin. They may also be at risk for developing systemic lupus erythematosus later in life. To define more clearly the pathogenesis and genetic influences in neonatal lupus, the present authors studied six families with the disease (almost 10 per cent of the reported cases). Seven children from the six families were examined clinically, serologically, and by HLA typing. The findings in these infants and their six mothers are given in Table 1.