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Medicine

Diagnostic Criteria and Treatment of Hemophagocytic Lymphohistiocytosis

Quick fact

In HLH, serum ferritin levels can exceed 10,000 ng/mL, a striking elevation that is a diagnostic hallmark and often contributes to the early recognition of this rapidly fatal syndrome.

Why this is interesting

You probably know that fever and enlarged organs can mean an infection—but what if it's your own immune system attacking your body? And how can a simple blood test for iron levels save a life?