Secondary Hemophagocytic Syndrome: The Importance of Clinical Suspicion

Table 1

Diagnosis criteria of HPS according to HLH-2004.

Diagnosis of HPS
(A) Molecular diagnosis consistent with HPS: PRF1, UNC13D, Munc18-2, Rab27a, STX11, SH2D1A, or BIRC4
Or
(B) 5 of 8 diagnostic criteria below:
(1) fever ≥ 38,5°C
(2) spleen enlargement
(3) cytopenias affecting at least 2 blood lineages in peripheral blood:
(a) hemoglobin < 9,0 g/dL
(b) platelets < 100 × 10^9
(c) absolute neutrophil count < 1,0 × 10^9
(4) elevated triglycerides (fasting > 265 mg/dL) and/or hypofibrinogenemia (<150 mg/dL)
(5) hemophagocytosis in bone marrow, spleen, lymph nodes, or liver
(6) absent or low NK-cell activity
(7) ferritin > 500 μg/L (>10 000 μg/L highly suspicious of HPS)
(8) elevated sCD25 (𝛼-chain of soluble IL-2 receptor) > 2400 U/mL

Adapted from Jordan et al. [1].