Red Blood Cell Distribution Width is a Potential Index to Assess the Disease Activity of Systemic Lupus Erythematosus

Background: General population-based investigations have revealed that red blood cell distribution width (RDW) is associated with inflammatory indexes such as erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). Chronic inflammation is one of the major components of many autoimmune diseases and RDW may reflect the severity of these autoimmune diseases as well. Therefore, the objective of this study was to investigate the correlation between RDW and disease activity of systemic lupus erythematosus (SLE).

Methods: The medical records of 131 SLE patients were retrospectively analyzed. Correlations between RDW and disease activity or other inflammatory indexes were analyzed. The effect of glucocorticoid treatment for three months on RDW was estimated in 3 newly diagnosed SLE cases.

Results: Increased RDW was observed in SLE patients. RDW was positively correlated with serum IgM, CRP, ESR, and SLE Disease Activity Index 2000 (SLEDAI-2K). Glucocorticoid treatment decreased both SLEDAI-2K and RDW.

Conclusion: RDW may be a useful index to estimate the disease activity of SLE.