LAUSR

BACKGROUND Alemtuzumab is a monoclonal antibody targeting CD-52, used for treating relapsing-remitting multiple sclerosis (RRMS). METHODS We present a case of a 44-year-old male with RRMS who was admitted due to fever and jaundice after starting treatment with alemtuzumab 12 months ago. RESULTS He was diagnosed with hemophagocytic syndrome (HS). Liver biopsy revealed images of hemophagocytosis in Kupffer cells of lobular sinusoid. Management consisted of treatment with corticosteroids. CONCLUSION HS is a severe condition marked by an excessive activation of the immune system that leads to a rapid and progressive multi-organ failure, so it is important to consider it in the differential diagnosis of a fever syndrome following the administration of alemtuzumab.