Lupus eritematoso sistémico activo, síndrome de activación macrofágica y sepsis

Macrophage activation syndrome (MAS) is a rare and severe entity characterized by excessive activation and proliferation of macrophages and T-lymphocytes. The usual triggers are infections, drugs, malignancy and autoimmune diseases. Systemic lupus erythematosus is frequently associated with MAS. In clinical practice, differential diagnosis between active systemic lupus erythematosus, MAS and an infection is a great challenge for the internist. This happens because signs, symptoms and laboratory data from these illnesses overlap to a large degree. The purpose of this paper is to present a report on two patients with active systemic lupus erythematosus, MAS, and sepsis.