Red blood cell distribution width to estimate lupus activity

Abstract

Objective The aim of the study was to study red blood cell distribution width (RDW) in systemic lupus erythematous (SLE) patients as a lupus activity marker. Background SLE is a multifactorial systemic autoimmune disease that can affect multiple organs. The general pathogenesis of this disease still needs a better understanding. RDW is a measure of the red blood cell size variation. Patient and methods This prospective study was carried in the Internal Medicine Department, Menoufia University Hospital, from March 2016 to August 2016. Our study included 58 patients with SLE activity, which was measured using the Systemic Lupus Erythematous Disease Activity Index. RDW was measured as one of the parameters of complete blood count. RDW was reported on the Sysmex XT. In this study we excluded any other causes of anemia and other connective tissue diseases. Results The study included 58 SLE patients: 20 systemic lupus patients with high activity and 38 systemic lupus patients with very high activity. RDW was higher in systemic lupus patients with very high activity than in systemic lupus patients with high activity. There was a highly significant correlation between RDW and Systemic Lupus Erythematous Disease Activity Index. There was a highly significant correlation between RDW and erythrocyte sedimentation rate. Conclusion There was statistically higher RDW in lupus patients with very high activity than in those with high activity; therefore, RDW can be used as a lupus activity marker. RDW was associated with the inflammatory process of SLE.