Macrophage activation syndrome: An unusual complication of brucellosis

Introduction: During acute septicemic brucellosis, macrophage activation syndrome is a rare but serious complication. We report two cases of acute brucellosis complicated by macrophage activation syndrome (MAS). Materials and methods: We conducted a retrospective study on the medical records of patients admitted for brucellosis complicated by SAM between February 2021 and January 2023. The diagnosis of brucellosis is based on the isolation of brucellosis in blood cultures and/or on positivity serology. The SAM was retained based on Henter's diagnostic criteria. Results: During the study period, 30 patients were hospitalized for brucellosis. The average age is 46.7 years. Acute brucellosis complicated by SAM was noted in two immunocompetent male patients aged 47 and 46 years. Both patients were hospitalized for treatment of recent acute fever with deterioration in general condition, chills and diffuse arthromyalgia. The biological assessment revealed an inflammatory syndrome and pancytopenia in our patients. Blood cultures were requested returning positive for Brucella spp. Both patients presented more than five diagnostic criteria for SAM (fever, SPM, severe pancytopenia, hypertriglyceridemia and hyperferritinemia, histological signs of hemophagocytosis). Our patients improved only under antibiotic therapy. Conclusion: Macrophage activation syndrome is a described but rare complication during brucellosis.