Prognostic Value of Blood-Based Inflammatory Biomarkers in Secondary Hemophagocytic Lymphohistiocytosis

Hemophagocytic lymphohistiocytosis (HLH) is a rare systematic immune disease manifested with excessive activation of lymphocytes and macrophages. This study was designed to explore the feasible prognostic factors of secondary HLH (sHLH).

We retrospectively analyzed 179 patients with newly diagnosed sHLH from January 2016 to May 2019 according to the HLH-2004 protocol. Baseline characteristics and laboratory results were reviewed.

The median age of all patients was 53 years, with a male/female ratio of 1.45. The commonest cause of HLH was malignancy. Of the 179 patients, 48.6% presented with Epstein-Barr virus (EBV) infection, 92.8% with hemocytopenia (at least 2 lineages), 60.3% with hypofibrinogenemia, 43.0% with hypertriglyceridemia (≥ 3 mmol/L), 99.4% with high ferritin, 97.8% with fever, 72.1% with splenomegaly, and 72.6% with hemophagocytosis. As to their prognosis, 122 patients died; the median survival was 88 days, with a 2-year survival rate of 26.72%. Univariate analysis confirmed neutrophil-to-lymphocyte ratio ˃ 2.53, lymphocyte-to-monocyte ratio (LMR) ≤ 4.43, platelet-to-lymphocyte ratio ˃ 227.27, red blood cell distribution width ˃ 14.6, red blood cell distribution width-to-platelet ratio (RPR) > 0.33, EBV infection, platelet ≤ 34 × 10⁹ /L, fibrinogen ≤ 1.34 g/L, alkaline phosphatase ˃ 182.4 U/L, adenosine deaminase ˃ 69.2 U/L, and ferritin ˃ 2318 ng/mL were associated with an inferior survival. In a multivariate model, LMR, RPR, and ferritin were considered as three independent factors.

Some blood-based inflammatory markers, which can be easily and cheaply detected, are significantly associated with the OS of HLH patients. LMR and RPR, superior to NLR, PLR, RDW, can be taken to predict the OS of patients with HLH.