Neonatal lupus presenting as a butterfly rash.

A 3-month-old African American boy was referred to the dermatology clinic with a 2-month history of skin hypopigmentation that his pediatrician had diagnosed as vitiligo. Before hypopigmentation developed, the rashes were erythematous. The boy was born at term via normal vaginal delivery after an uneventful pregnancy, and was tracking in the 90th centile for expected head circumference and weight development. He had 2 healthy siblings, and there was no family history of autoimmune disease.

The hypopigmentation involved a striking butterfly-shaped facial rash (Figure 1) and multiple oval patches on the patient’s abdomen (Appendix 1, available at www.cmaj.ca/lookup/doi/10.1503/cmaj.202246/tab-related-content). There were no signs of atopic or seborrheic dermatitis. Because of the distinctive rash, we suspected neonatal lupus erythematosus and investigated accordingly. Both the infant and his mother tested positive for antinuclear and anti-Ro antibodies. The baby’s electrocardiogram, echocardiogram, complete blood count and liver enzymes were normal. We diagnosed cutaneous neonatal lupus erythematosus, advised photoprotection and prescribed a 3-month course of tacrolimus 0.03% ointment, applied twice daily. At 12 months, the patient’s skin lesions had resolved and autoantibodies were negative. The mother did not show signs of an autoimmune disease, but future pregnancies will be monitored closely.

Figure 1:

Striking butterfly-shaped hypopigmentation on the face of a 3-month-old boy with neonatal lupus erythematosus.

Neonatal lupus erythematosus is an uncommon condition resulting from the passive transfer of maternal anti-Ro, anti-La or anti-ribonucleoprotein antibodies from mother to baby.1 It is characterized by the development of typical dermatological signs, congenital heart block and endocardial fibroelastosis. Infants with the condition can also present with hepatobiliary disease, cytopenias, macrocephaly or hydrocephalus.2 Vitiligo-like presentations of neonatal lupus erythematosus have been described in infants with darker skin.3 Vitiligo presenting in the neonatal period is exceptional and should prompt clinicians to investigate further. Subsequent pregnancies in women who have given birth to a child with either cardiac or cutaneous neonatal lupus erythematosus warrant maternal and fetal cardiac monitoring, as the risk of having a child with cardiac neonatal lupus erythematosus increases to 20%.1