Hemophagocytic syndrome, infection-associated

This code represents a severe, life-threatening systemic inflammatory response characterized by uncontrolled activation and proliferation of histiocytes and T-lymphocytes, leading to widespread hemophagocytosis. It is a secondary form of hemophagocytic lymphohistiocytosis (HLH) specifically triggered by an underlying infection. This condition results in multi-organ dysfunction due to cytokine storm and tissue damage.

Use this code when documentation clearly indicates a diagnosis of hemophagocytic syndrome where an infectious etiology is identified as the trigger. This includes cases associated with viral (e.g., EBV, CMV, HIV), bacterial, fungal, or parasitic infections. Supporting documentation should include laboratory findings consistent with HLH (e.g., fever, cytopenias, hyperferritinemia, hypertriglyceridemia, hypofibrinogenemia, elevated sCD25, hemophagocytosis on bone marrow biopsy) and identification of the causative infection.

• Always code the underlying infection first, followed by this code.
• Distinguish from primary (familial) HLH (D76.1) or HLH associated with malignancy (D76.3).
• Ensure documentation specifies "infection-associated" or "secondary to infection" to justify this specific code.