Incidence and spectrum of neonatal lupus erythematosus: A prospective study of infants born to mothers with anti-Ro autoantibodies

Objective Neonatal lupus erythematosus (NLE) is characterized by complete congenital heart block (CCHB), cutaneous rash, and laboratory abnormalities in infants born to mothers with autoantibodies directed against SSA/Ro, SSB/La, or both. We carried out a prospective study to determine the incidence of individual NLE features. Study design The study was performed in two centers: Toronto, Canada, and Milano, Italy. Mothers had been referred for the presence of anti-SSA/Ro autoantibodies, regardless of their diagnosis. All the children were seen at least once within the first 6 months of life for clinical evaluation and laboratory testing. The study group consisted of 128 infants born from 124 pregnancies in 112 women with anti-Ro antibodies with or without anti-La antibodies. Results There were two cases of CCHB for an overall percentage of 1.6%. Twenty-one children (16%) developed cutaneous NLE. Laboratory testing showed hematologic abnormalities in 27% of the babies and elevation of liver enzymes in 26%. Conclusions Mothers with autoimmune diseases and anti-Ro antibodies are at risk of delivering a child with NLE but at a low risk of delivering a child. with CCHB. Infants born to mothers with anti-Ro or anti-La antibodies should be monitored for other features of NLE in addition to CCHB.