Evaluation of the risk of anti-SSA/Ro-SSB/La antibody-associated cardiac manifestations of neonatal lupus in fetuses of mothers with systemic lupus erythematosus exposed to hydroxychloroquine
Izmirly PM, Kim MY, Llanos C et al.
Neonatal lupus (NL) is a pathological manifestation of passively acquired autoimmunity. Maternal SSA/Ro and/or SSB/La antibodies are almost universally present in cases of isolated fetal heart block. Cardiac manifestations of NL (cardiac-NL) include conduction disease and life-threatening cardiomyopathy. The estimated risk of cardiac-NL is 2% in the infants of anti-SSA/Ro-positive women without a prior affected pregnancy, although the recurrence rate is 10-fold higher in subsequent pregnancies. Given the potential involvement of Toll-like receptor (TLR) signaling in the promotion of cardiac inflammation and scarring, the current authors hypothesized that hydroxychloroquine (which inhibits the endosomal acidification required for TLR signaling) may prevent cardiac injury.