What is the HScore for diagnosing hemophagocytic lymphohistiocytosis (HLH)?

By William Aird

Generates score indicating likelihood of secondary HLH based on graded clinical and laboratory parameters. HScore calculator is found here.

diagnostic criteria
Known underlying immunosuppressionNA0 (no) or 18 (yes)HIV positive or receiving long‐term immunosuppressive therapy (e.g., glucocorticoids, cyclosporine).
Fever0 (<38.5) or 1 (38.5)0 (39.4)Persistent or recurrent high fever. Nearly universal in untreated HLH.
Hepatomegaly NA0 (no), 23 (hepatomegaly or splenomegaly), or 38 (hepatomegaly and splenomegalyAbnormal liver tests reported in about 80% of adults with HLH (hypoalbuminemia detected in most adults with HLH).
Splenomegaly 0 (no) or 1 (yes)0 (no), 23 (hepatomegaly or splenomegaly), or 38 (hepatomegaly and splenomegaly)Splenomegaly may be caused by infiltration by activated lymphocytes and histiocytes or it by an underlying condition triggering HLH.
Cytopenias 0 (one lineage) or 1 (two or three lineages)*0 (one lineage), 24 (two lineages), or 34 (three lineages)Especially thrombocytopenia and anemia in early stages; results primarily from severe cytokine-mediated myelosuppression.
High Ferritin level (ng/ml) 0 (<500) or 1 (500)0 (6,000)No specific ferritin level determined to be specific for HLH. However, the higher the ferritin the likelier the diagnosis of HLH.
Elevated triglyceride level NA0 (4)Hypertriglyceridemia is detected in 42%-85% of adults.
Low Fibrinogen level NA0 (>2.5) or 30 (<2.5)Hypofibrinogenemia detected in about 50% of adults with HLH.
Elevated triglyceride level or low fibrinogen level Triglycerides > 265 mg/dl and/or fibrinogen </= 15 mg/dL (1)NA
ASTNA0 (<30) or 19 (30)LDH and bilirubin may also be increased.
Hemophagocytosis features on bone marrow aspirate 0 (no) or 1 (yes)Hemophagocytosis in bone marrow 0 (no) or 1 (yes)If the bone marrow specimen is not conclusive, material may be obtained from other organs.
Elevated soluble IL-2 receptor 1 (sIL-2R ≥ 2,400 units/mL)NAsIL-2R (sCD25), a marker of T cell activation; not available at most medical centers, their utility in real-time diagnosis and monitoring remains limited.
Low or absent NK-cell activity1 (Yes)NANot available at most medical centers; their utility in real-time diagnosis and monitoring remains limited.