Table 4

Diagnostic criteria for HLH, classification criteria for MAS in sJIA and classification criteria for sJIA

Revised 2004 diagnostic criteria for HLH*2016 classification of MAS in sJIA†
EITHER:

  • Molecular genetic confirmation

OR

  • Five of the following:

    1. Fever

    2. Splenomegaly

    3. At least two of the following:

      1. Haemoglobin <90 g/L

      2. Platelets <100×109/L

      3. Neutrophils <1×109/L

    4. Either of:

      1. Fasting triglycerides ≥ 265 mg/dL (3.0 mmol/L), OR

      2. Fibrinogen ≤1.5 g/L

    5. Ferritin ≥500 µg/L

    6. Tissue haemophagocytosis

    7. Decreased NK cell function

    8. sIL-2R ≥2400 U/mL

A febrile patient with known or suspected sJIA with:

  1. Ferritin >684 µg/L AND

  2. Any two of the following:

    • Platelets ≤181×109/L

    • AST >48 IU/L

    • Triglycerides >156 mg/dL (1.76 mmol/L)

    • Fibrinogen ≤3.6 g/L

ILAR classification of sJIA‡
Arthritis in more than one joints with or preceded by fever for ≥3 days, accompanied by more than one of the following:

  • Evanescent erythematous rash

  • Generalised lymphadenopathy

  • Hepatomegaly and/or splenomegaly

  • Serositis

AND exclusion of: A, B, C, D

  • Exclusions:

  • A: Psoriasis, or history of psoriasis, in patient or first-degree relative.

  • B: HLA-B27 positive, male and older than 6 years.

  • C: Ankylosing spondylitis, enthesitis-related arthritis, sacroiliitis with inflammatory bowel disease, Reiter syndrome or acute uveitis, or history of one of these in first-degree relative.

  • D: Presence of IgM rheumatoid factor on two or more occasions ≥3 months apart.

  • *Based on Henter et al.30

  • †Based on Ravelli et al.38

  • ‡Based on Petty et al.39

  • AST, aspartate aminotransferase; HLH, haemophagocytic lymphohistiocytosis; ILAR, International League of Associations for Rheumatology; MAS, macrophage activation syndrome; NK, natural killer; sIL-2R, soluble interleukin-2 receptor; sJIA, systemic juvenile idiopathic arthritis.