Cutaneous manifestations of neonatal lupus and risk of subsequent congenital heart block

Objective. Cutaneous disease associated with placental transport of maternal anti-SSA/Ro or anti-SSB/La antibodies is transient, and children often appear to be otherwise healthy. However, the impact of this manifestation of neonatal lupus (NL) on the risk of cardiac disease occurring in a future pregnancy is critical for family counseling and for powering preventive trials. The purpose of this study was to determine the recurrence rates of NL, with specific focus on cardiac NL following cutaneous NL in a child enrolled in the Research Registry for Neonatal Lupus (RRNL). Methods. Fifty-eight families who were enrolled in the RRNL met the following inclusion criteria for our study: maternal anti-SSA/Ro or anti-SSB/La antibodies, a child with cutaneous NL, and a pregnancy subsequent to the child with cutaneous NL. Results. The majority of the 58 mothers (78%) were Caucasian. Of 77 pregnancies that occurred following the birth of a child with cutaneous NL, the overall recurrence rate for any manifestation of NL was 49% (95% confidence interval [95% CI] 37-62%); 14 pregnancies (18.2%) were complicated by cardiac NL, 23 (29.9%) by cutaneous NL, and 1 (1.3%) by hematologic/ hepatic NL. A subset analysis was restricted to the 39 children who were born after the initial child with cutaneous NL had been enrolled in the RRNL. The overall recurrence rate for NL was 36% (95% CI 20-52%); 5 pregnancies (12.8%) were complicated by cardiac NL and 9 (23.1%) by cutaneous NL. There were no significant differences in the following maternal risk factors for having a subsequent child with cardiac or cutaneous NL: age, race/ethnicity, anti-SSB/La status, diagnosis, use of nonfluorinated steroids, or breastfeeding. The sex of the subsequent fetus did not influence the development of cardiac or cutaneous NL. Conclusion. Based on data from this large cohort, the identification of cutaneous NL in an anti-SSA/Ro antibody-exposed infant is particularly important, since it predicts a 6-10-fold risk of a subsequent child developing cardiac NL.