Table 26.1.
Diagnostic guidelines for Hemophagocytic Lymphohistiocytosis (HLH)
| The diagnosis of HLH can be established by fulfilling either or both of the two criteria below |
| 1. A molecular diagnosis consisted with HLH |
| 2. Diagnostic criteria (five out of the eight criteria must be met) |
| (a) Fever |
| (b) Splenomegaly |
| (c) Cytopenias (affecting at least two of three lineages in the peripheral blood) |
| (i) Hemoglobin <90 g/L (in infants < 4 weeks: hemoglobin <100 g/L) |
| (ii) Platelets <100 × 109/L |
| (iii) Neutrophils <1.0 × 109/L |
| (d) Hypertriglyceridemia and/or hypofibrinogenemia |
| (i) Fasting triglycerides ≥3.0 mmol/L (i.e., ≥ 265 mg/dl) |
| (ii) Fibrinogen ≤1.5 g/L |
| (e) Hemophagocytosis in bone marrow, spleen, lymph nodes, or cerebrospinal fluid |
| (f) Low or absent NK-cell activity |
| (g) Ferritin ≥500 μg/L |
| (h) Soluble CD25 (soluble IL-2 receptor) above normal limits for age |