Macrophage Activation Syndrome as the First Impression of Kawasaki Disease; A Case Report

Introduction Macrophage activation syndrome (MAS) is a rare and life-threatening complication of Kawasaki Disease (KD) that is usually diagnosed at the same time or after KD. We report a case of MAS as the initial manifestation of KD. Case Report A previously healthy 3-year old girl was admitted to the pediatric infectious diseases ward of Bahrami Children’s Hospital, Tehran, Iran. She had a 3-day history of fever and lymphadenopathy which persisted despite antibiotic therapy. Patient's general condition gradually worsened and she developed loss of consciousness. After being diagnosed with MAS based on laboratory findings, she developed mucocutaneous manifestations of KD. She responded to methylprednisolone pulse therapy, intravenous immunoglobulin and dipyridamole. The follow-up at 2 weeks and 2 months showed no abnormal findings. Conclusion MAS may manifest even before the diagnosis of KD is made.  Early recognition of MAS associated with KD and prompt treatment with corticosteroids can improve the outcome.