Transient heart block in a neonate associated with previously undiagnosed maternal anti-Ro/SSA and anti-La/SSB antibodies.

This report presents the case of an infant who was born with transient complete heart block. The cardiac rhythm converted to normal sinus rhythm within 12 hours of life. Following the diagnosis in this infant of congenital heart block, both the mother and the infant were tested for autoantibodies. Both were found to be strongly positive for anti-Ro/SSA antibodies. The infant was also weakly positive for the anti-La/SSB antibodies and her mother moderately positive for the same. Congenital heart block associated with these maternal antibodies is well documented in the literature; however, this is the only reported case that documents a transient nature of the complete heart block.