Skip to content
ClinCalc Pro
Menu
haematology rheumatology infectious-disease

HScore for Haemophagocytic Lymphohistiocytosis

HScore predicts probability of reactive haemophagocytic syndrome (HLH/MAS). Score ≥169 associated with >93% probability of HLH. Guides early immunosuppressive treatment.

Score interpretation

HLH Highly Probable (>93%)

→ HScore ≥169: >93% probability of HLH. Initiate HLH-94 protocol (dexamethasone + etoposide + cyclosporin if indicated); treat underlying trigger (infection, malignancy, rheumatic); haematology urgent review; bone marrow biopsy; NK cell function; sCD25; consider IVIG.

HLH Possible (30–93%)

→ HScore 100–168: Intermediate HLH probability (30–93%). High suspicion; urgent bone marrow; ferritin, fibrinogen, sCD25, NK cell function; rheumatology/haematology joint review; empirical immunosuppression if deteriorating.

HLH Unlikely (<30%)

→ HScore <100: <30% probability of HLH. Consider alternative diagnoses (infection, malignancy, autoimmune). Complete diagnostic workup; review HScore if clinical picture evolves.

Interpretation bands for the HScore (HLH). Apply clinical judgement and local guidance.

References

Related

Curated clinical cross-links plus same-class fallbacks.

Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.