Neonatal lupus erythematosus mimicking langerhans cell histiocytosis.

Neonatal lupus erythematosus (NLE) is an autoimmune disease characterized primarily by transient skin lesions and/or permanent congenital heart block. Other clinical findings include self-limited cytopenias and liver disease. The syndrome results from the passive transfer of maternal anti-SSA, anti-SSB, or anti-U1RNP autoantibodies to the fetus across the placenta. The cutaneous manifestations are generally analogous to those of subacute cutaneous lupus erythematosus (SCLE) and consist of small, erythematous macules that progress to annular plaques with delicate scaling. The skin lesions usually resolve within the first 6 months of life as maternal autoantibodies are cleared from the infant's circulation. We describe a patient with cutaneous NLE with hepatic and hematologic manifestations. The clinical presentation was atypical, with splenomegaly and petechiae at birth followed by a crusting, papulosquamous skin eruption of the scalp and face mimicking Langerhans cell histiocytosis (LCH).