This summary discusses infant and neonate patients. Systemic lupus erythematosus in adults and children is addressed separately.

Neonatal lupus erythematosus (NLE) is an autoimmune disorder of the newborn caused by placental transmission of maternal autoantibodies. Anti-SSA/Ro, anti-SSB/La, and anti-U1RNP antibodies can be found in both the fetal and maternal circulation.

The most frequently reported clinical manifestations of NLE include autoimmune congenital heart block, which may be detected in utero, cutaneous manifestations, autoimmune hepatitis, and cytopenias. The heart block occurs in up to 2% of affected infants, and 80% of these patients ultimately require a cardiac pacemaker. Eighty percent of infants with neonatal lupus and congenital heart block have positive anti-SSA/Ro and anti-SSB/La antibodies, but anti-U1RNP is almost universally negative in this setting. The cardiac complications carry a mortality rate between 16% and 23% through the first year of life; a fatal cardiomyopathy is usually implicated.

Skin manifestations of NLE are present at birth in two-thirds of patients; the remainder appear by the age of 5 months. The face is involved most frequently, but any body surface may be affected. Plaques generally heal within a year.

Elevated liver enzymes, thrombocytopenia, anemia, and neutropenia may be seen. These will resolve as the maternal antibodies are cleared, usually between the ages of 6 and 8 months.