Abstract: Background   Lupus nephritis（LN）is an important cause of complications and mortality in systemic lupus erythematosus， and its pathogenesis is very complex. In recent years，neutrophil-to-lymphocyte ratio （NLR），platelet-to-lymphocyte ratio （PLR）as new inflammatory indicators have been used to evaluate many diseases. However，there are few studies on the use of NLR and PLR in evaluating LN disease activity. Objective　To evaluate the predicative value of NLR and PLR for disease activity in patients with LN．Methods　The enrolled 130 participants were all from the Affiliated Huaian No.1 People's Hospital of Nanjing Medical University from March 2013 to March 2018，66 of whom were LN inpatients and other 64 were physical examinees from the Medical Examination Center.LN activity was assessed by systemic lupus erythematosus disease activity index （SLEDAI），and according to the results，16 LN cases were found with inactive LN （SLEDAI≤9） and 50 with active LN （SLEDAI≥10）．Data concerning sex，age，white blood cell count，hemoglobin，platelet count，neutrophil count，lymphocyte count and calculated NLR and PLR of LN patients and controls were collected.Moreover，duration of LN，erythrocyte sedimentation rate （ESR），C-reactive protein，C3 and C4 complements，plasma albumin，serum creatinine，urea nitrogen，uric acid and 24-hour urinary protein of LN patients were collected.Receiver operating characteristic （ROC） curve was performed to explore the value of NLR and PLR in the prediction of LN activity.Results　The mean levels of hemoglobin，platelet count，and lymphocyte counts were significantly lower，however，mean NLR and PLR were significantly higher in LN patients compared to those of the controls （P<0.05）．The mean levels of white blood cell count，platelet count，lymphocyte counts，C3 and C4 complements were significantly lower，but mean NLR and PLR were significantly higher in active LN patients compared with those of inactive LN patients （P<0.05）．NLR was positively correlated with SLEDAI score （rs=0.360，P=0.003）．ROC curve analysis revealed that in the prediction of LN activity，the AUC of NLR was 0.755〔95%CI （0.634，0.876），P=0.002〕，the optimal cut-off value was 4.06，with 68% sensitivity and 75% specificity；the AUC of PLR was 0.698〔95%CI （0.563，0.832），P=0.018〕，the optimal cut-off value was 184，with 64% sensitivity and 75% specificity.Conclusion　NLR and PLR can be used as new inflammatory markers and as potential complementary markers for diagnosing LN disease activity.

Key words: Lupus nephritis, Disease activity, Neutrophil to lymphocyte ratio, Platelet to lymphocyte ratio

摘要： 背景　狼疮性肾炎（LN）是导致系统性红斑狼疮并发症和死亡的重要原因，其发病机制十分复杂。近年来，中性粒细胞与淋巴细胞比值（NLR）、血小板与淋巴细胞比值（PLR）作为新的炎性指标，被用于评估许多疾病。然而目前关于NLR、PLR用于评估LN疾病活动度度的研究尚不多见。目的　探讨NLR和PLR预测LN疾病活动度的价值。方法　选取2013年3月—2018年3月在南京医科大学附属淮安第一医院住院的66例LN患者作为LN组，选取同时期本院体检中心的64例健康体检者为健康对照组，依据系统性红斑狼疮疾病活动指数（SLEDAI）将LN患者分为LN稳定亚组（SLEDAI≤9分，16例）和LN活动亚组（SLEDAI≥10分，50例）。收集健康对照组患者和LN患者的性别、年龄，并检测白细胞计数、血红蛋白、血小板计数、中性粒细胞计数、淋巴细胞计数，计算NLR和PLR；记录LN患者的疾病持续时间、红细胞沉降率（ESR）、C反应蛋白（CRP）、补体C3、C4、血浆清蛋白、肌酐、尿素氮、尿酸、24 h尿蛋白定量。采用受试者工作特征（ROC）曲线评价NLR、PLR预测LN疾病活动度的价值。结果　LN组血红蛋白、血小板计数、淋巴细胞计数均低于健康对照组，NLR、PLR均高于健康对照组（P<0.05）。LN活动亚组患者白细胞计数、血小板计数、淋巴细胞计数、补体C3、C4水平均低于LN稳定亚组，NLR、PLR均高于LN稳定亚组（P<0.05）。NLR与SLEDAI呈正相关（rs=0.360，P=0.003）。ROC曲线显示，NLR诊断LN疾病活动度的ROC曲线下面积（AUC）为0.755〔95%CI（0.634，0.876），P=0.002〕，当最佳临界值为4.06时，灵敏度为68%，特异度为75%；PLR诊断LN疾病活动度的AUC为0.698〔95%CI（0.563，0.832），P=0.018〕，当最佳临界值为184时，灵敏度为64%，特异度为75%。结论　NLR、PLR可作为新的炎性指标，被用作诊断LN疾病活动度的潜在补充评估指标。

关键词: 狼疮肾炎, 疾病活动度, 中性粒细胞与淋巴细胞比值, 血小板与淋巴细胞比值