D2I2.
immune

Haemophagocytic lymphohistiocytosis

In hematology, hemophagocytic lymphohistiocytosis (HLH), also known as haemophagocytic lymphohistiocytosis, and hemophagocytic or haemophagocytic , is an uncommon hematologic disorder seen more often in children than in adults. It is a life-threatening disease of severe hyperinflammation caused by uncontrolled proliferation of lymphocytes and macrophages that secrete high amounts of cytokines. It is classified as one of the cytokine storm syndromes.

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Plain-language summary adapted from Wikipedia. Not medical advice.