Association Between Neutrophil-to-lymphocyte Ratio,Platelet-to Lymphocyte Ratio And Untreated New-onset Systemic Lupus Erythematosus

Objective: Current studies have confirmed that neutrophil to lymphocys ratio(NLR)and platelet-to-lymphocyty ratio(PLR)are important indicators of response to systemic inflammation levels.This study explores the correlation between NLR and PLR levels with systemic lupus erythematosus(SLE)laboratory indicators and disease activity by assessing levels of NLR and PLR in SLE patients.Methods: this study is a case control study.154 first diagnosed SLE patients without treatment in the second affiliated hospital of Anhui Medical University and 151 healthy people from the medical examination center were selected as the healthy control(HC)group to collect the relevant demographic characteristics,laboratory examination and other relevant data.According to the absence of kidney involvement,the patients were divided into non-lupus nephritis(LN)group and LN group;according to the systematic lupus disease activity index(SLEDAI)scores,the patients were divided into high disease activity group and low disease activity group;the correlation between NLR,PLR and SLEDAI scores were assessed by Spearman correlation coefficient.ROC curve analysis was drawn to determine the sensitivity and specificity of NLR and PLR in predicting the SLE and SLE with nephritis.Results: The clinical manifestations of SLE were multiple tissue and organ involvement.the most frequently involved organs were skin and mucous membrane(51.3%),blood system(47.4%),kidney(47%),while lung,nervous system,cardiovascular system,digestive system and so on were less involved.Compared with the healthy controls,the NLR,PLR levels in the SLE group were significantly increased[2.40(1.49,3.52)and 1.55(1.11,2.06);161.26(107,214.24)and 109.15(84.19,138.55)respectively;all p <0.001].There was no statistical difference in age and sex between the two groups.154 patients with SLE,of which 72 were lupus nephritis(LN)group,accounting for 47%;82 were non-lupus nephritis group,accounting for 53%.The NLR,PLR level of SLE patients without nephritis were distinctly lower compared LN patients(both <0.05).SLEDAI scores was positively associated with NLR and PLR.According to the Receiver-operating characteristic(ROC)curve,the optimal NLR cut-off value to predict SLE and LN was 2.133 and 1.844,with 58.44% and 80.56% sensitivity,78.15%and 48.78% specificity respectively.However,the best PLR cut-off value to predict SLE and LN was 147.3 and 189,with 57.14% and 43.06% sensitivity,84.11% and74.39% specificity correspondingly.Conclusions: Compared with healthy controls,both NLR and PLR in SLE peripheral blood are significantly elevated,and which are positively correlated with SLEDAI.Moreover,NLR and PLR are of high value in the diagnosis of SLE,providing new clues for the prevention and treatment of SLE.