[Multi-organ failure as first clinical sign of macrophage activation syndrome in childhood Still's disease]. / Fracaso multiorgánico como forma de presentación del síndrome de activación macrofágica en la enfermedad de Still infantil.

Macrophage activation syndrome is a form of secondary haemophagocytic lymphohistiocytosis seen in the context of rheumatic diseases. It is seen most frequently in association with systemic onset juvenile arthritis or childhood Still's disease. Hemophagocytosis is part of a sepsis-like clinical syndrome caused by hypercytokinemia due to a highly stimulated but ineffective immune response. Coagulopathy and hemorrhages, decreased white cell count, elevated levels of aspartate aminotransferase, fever, rash, hepatosplenomegaly and central nervous system dysfunction are some of diagnostic criteria of macrophage activation syndrome, but it is very difficult to diagnose due to the lack of specific clinical signs. We report a 8-year-old child who was admitted to the ICU with lethargy, fever, acute respiratory failure, coagulopathy, metabolic acidosis and multiorgan failure. Septic shock was suspected, but he was diagnosed with macrophage activation syndrome and treated with corticosteroids and intravenous immunoglobulin and later discharged from the ICU.