Neonatal Lupus
A previously healthy, full-term, 2-month-old boy was brought to the dermatology clinic with a 2-week history of red spots that had spread across his face. On physical examination, annular plaques with edematous borders and central crusting were observed on the baby’s face, scalp, and trunk. Results of a complete blood count and comprehensive metabolic panel were normal. Testing for syphilis was negative. Anti-Ro and anti-La antibodies were positive in both the infant and the mother, the latter of whom was asymptomatic and had no history of autoimmune disease. Examination of a skin-biopsy sample obtained from the baby’s right forehead showed vacuolar interface dermatitis and perivascular and periadnexal lymphocytic infiltrates. A diagnosis of neonatal lupus was made. Neonatal lupus results from the passive transfer of maternal anti-Ro and anti-La across the placenta. The associated rash may be present at birth but more often appears several weeks later, after the infant has been exposed to the sun. An electrocardiogram that was obtained to evaluate for atrioventricular block was normal. Reassurance was provided to the baby’s mother about the self-limited nature of the rash, and a recommendation was made for the use of photoprotection. Given her high risk for the development of autoimmune symptoms, the mother was referred to the rheumatology clinic. At the 2-month follow-up, the baby’s rash had resolved. source:nejm.org
