Clinical Usefulness of Hematologic Indices as Predictive Parameters for Systemic Lupus Erythematosus

Objective: This study assessed the neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), mean platelet volume, platelet distribution width, and red cell distribution width (RDW) in systemic lupus erythematosus (SLE) patients and their correlation with disease activity. Methods: Two hundred eight SLE patients and 205 age- and sex-matched healthy controls were included. Disease activity was assessed using the systemic lupus erythematosus disease activity index 2000, and hematological indices were determined. Results: Lymphocyte and platelet counts were significantly lower in SLE patients than in the controls, while the NLR, PLR, and RDW were significantly higher (P < .05). In patients with active disease, the neutrophil counts, NLR, and PLR were significantly higher than in those with inactive disease (P < .05), while the lymphocyte count was significantly lower (P < .05). Based on receiver operating characteristic curve analyses, only for lymphocyte count and PLR. The area under curve was significantly higher (P = .001 and P = .053, respectively). Conclusion: PLR can serve as a biomarker for indicating SLE disease activity.