Application Of Red Blood Cell Distribution Width And Neutrophil To Lymphocyte Ratio In Assessment Of Systemic Lupus Erythematosus Severity

Objective : To investigate the values of the red blood cell distribution width(RDW),neutrophils counts,lymphocytes counts and neutrophil to lymphocyte ratio(NLR)in newly diagnosed patients with systemic lupus erythematosus(SLE),explore their clinical significance in assessment of disease activity.Methods : In this study a total of 181 newly diagnosed SLE patients who were admitted to the Second Hospital of Anhui Medical University between August 2014 and August2016 and the definition of SLE was according to the American College of Rheumatology criteria.Meanwhile,190 healthy individuals who underwent routine physical examinations in the Second Hospital of Anhui Medical University Health Management Center were enrolled as controls.Under the condition of informed consent,fasting anticoagulant 3.6ml and non-anticoagulant 4ml were collected both patients and controls.With automatic blood analyzer as the testing platform,the comprehensive application of semiconductor laser flow cytometry and radioimmunoassay combined with nucleic acid fluorescent staining to detect blood routine parameters such as RDW,neutrophils and lymphocytes counts and so on.The automatic biochemical analyzer was used to measure the serum biochemical indexes such as C-reactive protein(CRP),C3,C4,immunoglobulin A(Ig A),immunoglobulin G(Ig G),immunoglobulin M(Ig M)and so on.All of the serum biochemical indexes were measured by immunoturbidimetry.Anti-nuclear antibody(ANA)titers were detected by indirect immunofluorescence using HEp-2 cells and monkey liver as antigenic substrates.The extractable nuclear antigen(ENA)antibodies such as anti-ds DNA antibody,anti-Sm antibody,anti-histone antibody,anti-nucleosome antibody were detected by Western blotting.The SLE Disease Activity Index 2000(SLEDAI-2K)scale was used to evaluate the activity of the patients and grouped as follows: no active(0~4),mild activity(5~9),moderate activity(10~14),severe activity(? 15).T-test was used to compare the differences of RDW,lymphocytes and neutrophils counts,neutrophil to lymphocyte ratio among the two groups.The differences of RDW among the four groups were analyzed with the one-way ANOVA and Student-Newman-Keuls(SNK)was used to compare pairs of four groups.Pearson's correlation coefficients were calculated to explore the relationships between RDW,lymphocytes and neutrophils counts,NLR and SLEDAI-2K in patients with SLE.Results : The levels of red blood cell distribution width(14.64 ± 2.13vs12.43 ± 0.44)and neutrophil to lymphocyte ratio(3.20 ± 2.67vs1.84 ± 0.56)were significantly higher in patients with SLE than those of control group(t=16.36,6.90,P<0.001),and the levels of lymphocytes counts were lower than that of control group(1.46 ± 0.67 vs 1.99± 0.47,t=8.89,P<0.001),but there were no significant difference in neutrophils counts level(3.81 ± 1.89 vs 3.51 ± 0.95,t=1.93,P=0.055).The levels of RDW and NLR were positively correlated with SLEDAI-2K(r=0.725,P<0.001;r=0.16,P=0.030),and lymphocytes counts were negatively correlated with SLEDAI-2K(r=-0.30,P<0.001).RDW were positively correlated with ESR and CRP(r=0.628,0.663,P<0.001)but negatively correlated with serum C3 and C4(r=-0.348,-0.273,P<0.001).The RDW values in no active,mild activity,moderate activity,and severe activity groups of newly diagnosed patients with SLE were(13.27 ± 0.77),(14.74 ± 0.80),(15.51 ± 1.21)and(17.24 ± 1.13).The results showed that the RDW increased significantly with the increase of disease activity and a significant difference were found between different stages of activity groups in patients with SLE(F=99.66,P<0.001).There were also differences between any two for the four groups(P<0.05).Conclusion : The red blood cell distribution width and neutrophil to lymphocyte ratio were significantly higher in newly diagnosed patients with systemic lupus erythematosus and positively correlated with SLEDAI-2K.There was also a positive correlation between red blood cell distribution width and inflammatory markers.Therefore,the red blood cell distribution width and neutrophil to lymphocyte ratio have potential value in assessment of newly diagnosed patients with systemic lupus erythematosus disease activity.