Macrophage activation syndrome (MAS) is a potentially life-threatening complication in many autoimmune diseases. Early recognition and intervention are essential for a favorable outcome. Neonatal lupus, an acquired autoimmune disease in neonates caused by the transplacental passage of maternal autoantibodies, is rare and usually self-limited. Herein, we report a case of MAS in a patient with neonatal lupus, which improved with intravenous immunoglobulin.

Macrophage activation syndrome (MAS) is a potentially life-threatening complication in many autoimmune diseases. Early recognition and intervention are essential for a favorable outcome. Neonatal lupus, an acquired autoimmune disease in neonates caused by the transplacental passage of maternal autoantibodies, is rare and usually self-limited. Herein, we report a case of MAS in a patient with neonatal lupus, which improved with intravenous immunoglobulin.