Cutaneous Lupus Erythematosus in Neonates and Infants: Maternally Derived Autoimmunity and the Neonatal Lupus Syndrome

Neonates are not sufficiently immunologically competent to develop IgG autoantibody–mediated disease independently. However, IgG autoantibodies from the mother transmitted in utero can initiate disease in susceptible individuals. In a small percentage of fetuses and neonates exposed to maternal autoantibodies of the Ro/SSA family, an autoimmune disease called “neonatal lupus erythematosus (NLE)” will develop (Lee 1993, 2001). It may be argued that NLE is misnamed, as many of its clinical findings are not shared by systemic LE (SLE) of children or adults, but the name NLE remains in common use. The main features of the syndrome are cutaneous lupus lesions, cardiac disease (primarily complete congenital heart block), hepatobiliary disease, and hematologic cytopenias. Many affected individuals have only one manifestation of NLE, but any combination of these findings may occur. NLE is an uncommon condition. Although approximately 1 in 200 pregnant women have anti-Ro/SSA autoantibodies, few have a child with NLE (Harmon et al. 1984). The incidence of NLE has been estimated as 1 in 20,000 live births (Lee and Weston 1996). Cardiac disease is reportedly the most common feature, but this may be due in part to its being more likely than the other manifestations to be detected and properly diagnosed. The sex distribution is approximately equal for children with cardiac NLE, but girls outnumber boys approximately 2:1 in cases of cutaneous NLE (Buyon et al. 1998, Neiman et al. 2000).