RESUMEN
Neonatal lupus erythematous is a rare syndrome, which is characterized by a transient lupus dermatitis, hematologic abnormalities and isolated congenital heart block. We detected the atrioventricular dissociation, bradycardia and pericardial effusion by fetal echocardiography in a female fetus at 25th weeks of gestational age. The baby was born in the 38th week of pregnancy by Cesarean section with 1790 gram of body weight. In spite of atrioventricular dissociation with bradycardia and pericardial effusion, cardiac pacemaker was not needed during neonatal period because she was doing well, no evidence of congestive heart failure and around 80 beat per minute of heart rate. The serologic markers for diagnosis of neonatal lupus are the autoantibodies specific to SS-A/Ro and/or SS-B/La. These antibodies are produced by the mother and passed to the fetus through the placenta. Autoantibodies of cytoplasmic SS-A antigens or SS-B antigen were found in the blood of this patient and her mother. We report a case of neonatal lupus syndrome with congenital atrioventricular dissociation with Rt. Bundle branch block and hematologic abnormality.