Archives of Clinical Rheumatology

Macrophage Activation Syndrome (MAS) is a severe inflammatory complication often linked to autoimmune disorders such as systemic lupus erythematosus (SLE). We describe a 57-year-old woman who presented with persistent fever, polyarthralgia, pancytopenia, and markedly elevated ferritin levels (>40,000 ng/mL). Extensive evaluation ruled out infection and malignancy. A diagnosis of MAS was made, and she responded well to high-dose corticosteroids and anakinra.