What to do When the Immune System Goes into a Storm?

The hemophagocytic lymphohistiocytosis (HLH) and the macrophage activation syndrome (MAS) represent excessive and pathological inflammation constellations, which due to the characteristically significantly increased ferritin are also summarized under the umbrella term “hyperferritinemia syndromes”. Congenital defects of cytotoxicity or certain rheumatic diseases (systemic JIA, collagenoses) are typical underlying diseases, in the context of which an HLH or a MAS can develop.