A Case of Neonatal Lupus Syndrome with Acute Myocarditis

ABSTRACT

Neonatal lupus is a model of passively acquired autoimmunity in which immune abnormalities in the mother lead to production of antibodies that cross the placenta and injure the developing fetus. The serologic markers for the diagnosis of neonatal lupus are auto-antibodies specific to SS-A/Ro and/or SS-B/La. More than 95% of affected infants are anti-SS-A/Ro positive. We experienced a neonatal lupus with acute myocarditis at 2 months of age. The baby was born in gestational age of 36 weeks with a birth weight of 2,350gm by Caesarean section. At birth, chest X-ray showed mild cardiomegaly, but electrocardiography and echocardiography were normal. Laboratory findings for LDH, CPK and CK-MB were increased above the normal range. At 2 months of age, controlled echocardiography showed dilated left ventricle(LV) dimension with decreased fractional shortening and ejection fraction. However, this infant did not show clinical symptoms of congestive heart failure. We followed up on this patient without giving any medical treatment. At 1 year of age, controlled echocardiography showed increased thickness of the posterior wall of LV, but the fractional shortening and ejection fraction returned to normal range.