Haematology Oncology Critical Care

HScore for Reactive Haemophagocytic Syndrome (HLH)

Estimates the probability of reactive haemophagocytic syndrome (rHPS / HLH) using 9 clinical and laboratory parameters.

Used in: Anaemia

Score interpretation

HLH Very Unlikely (< 1%) 0–89

HScore < 90: < 1% probability of reactive HLH.

→ HLH unlikely. Consider alternative diagnoses.

HLH Unlikely (~1–9%) 90–129

HScore 90–129: about 1–9% probability of reactive HLH (Fardet 2014).

→ Low probability. Monitor. Repeat ferritin. Consider bone marrow biopsy if clinical suspicion persists.

Intermediate Probability (~9–25%) 130–149

HScore 130–149: about 9–25% probability of reactive HLH.

→ Intermediate probability. Bone marrow biopsy recommended. NK cell activity, sCD25. Urgent haematology review.

High Probability (~25–54%) 150–168

HScore 150–168: about 25–54% probability of reactive HLH.

→ High clinical suspicion. Treat presumptively if clinical scenario fits. HLH-2004 or DEP protocol.

HLH Likely (HScore ≥ 169) 169–400

HScore ≥ 169 is the best diagnostic cut-off (sensitivity 93%, specificity 86%); probability about 40–54% at 161–170, 88–93% at 201–210 and > 99% at 241 or more.

→ Initiate HLH treatment immediately (dexamethasone ± etoposide ± ciclosporin). Treat underlying trigger. ICU-level care.

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

References

Fardet L et al. Development and Validation of the HScore, a Score for the Diagnosis of Reactive Hemophagocytic Syndrome. Arthritis Rheumatol. 2014;66(9):2613-2620.

Curated clinical cross-links plus same-class fallbacks.

Drugs

Pathways

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

Score interpretation

References

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