Table 1.
Diagnostic guidelines for HLH based on the HLH-2004 protocola
| Guideline | Description |
|---|---|
| 1 | Molecular diagnosis consistent with HLH |
| 2 | Diagnostic criteria for HLH fulfilled (≥5 of the 8 criteria below) |
| (a) Fever | |
| (b) Splenomegaly | |
| (c) Cytopenias (affecting at least 2 of the following 3 parameters in the peripheral blood) | |
| Hemoglobin, <90 g/liter (<100 g/liter in infants <4 wk old) | |
| Platelets, <100 × 109/liter | |
| Neutrophils, <1.0 × 109/liter | |
| (d) Hypertriglyceridemia and/or hypofibrinogenemia | |
| Fasting triglycerides, ≥3.0 mmol/liter (≥265 mg/dl) | |
| Fibrinogen, ≤1.5 g/liter | |
| (e) Hemophagocytosis in bone marrow, spleen, lymph nodes, or cerebrospinal fluid; no evidence of malignancy | |
| (f) Low or absent NK cell activity (according to local laboratory reference) | |
| (g) Elevated ferritin (≥500 U/liter) | |
| (h) Soluble CD25 (i.e., soluble IL-2R) above normal limits for age |
a
The diagnosis of HLH can be established by one or both of the guidelines described in the table, which has been adapted from reference 8 with permission of the publisher.