免疫球蛋白轻链在糖尿病肾病中的变化及意义

Changes and significance of immunoglobulin light chain in diabetic nephropathy

目的探讨血清游离轻链(free light chains,FLCs)与糖尿病肾病(DN)患者的临床指标及肾病理病变的关系。方法选取肾内科住院,并经肾活检诊断的DN患者40例为试验组,非DN患者40例为对照组,两组患者均除外慢性炎症性疾病。记录患者血肌酐、尿蛋白、超敏C反应蛋白(hs-CRP)、同型半胱氨酸(homocysteine,Hcy)等临床指标。应用间接免疫荧光法检测各肾标本中λFLC及κFLC的表达情况,并记录其光镜下肾脏病变情况。测定各患者λFLC及κFLC浓度。探讨FLCs与DN患者临床指标及肾病理病变的关系。结果试验组入院时hs-CRP及Hcy均高于对照组(P<0.05)。与对照组相比,试验组血清cFLC(combined free light chain,cFLC)(κFLC与λFLC之和)水平明显升高(P<0.05)。临床指标与cFLC进行相关性分析,结果显示Hcy、hs-CRP与cFLC呈正相关(P<0.05),病理学指标与cFLC进行相关性分析,DN肾间质小管病变评分与cFLC水平呈正相关(P<0.05),与eGFR呈负相关(P<0.05)。结论 FLCs可能可以作为预测DN患者死亡风险,尤其是预测心血管疾病风险的指标,并可以作为DN患者疾病进展的评估指标。

Objective To investigate the relationships among serum free light chains（FLCs）and clinical indicators and renal pathological changes of diabetic nephropathy（DN）.Methods Forty DN patients and 40non-DN patients were enrolled.The participants were divided into experiment and control group,but chronic inflammatory disease was exclued.Serum creatinine,urinary protein,hs-CRP and Hcy were observed.TheλFLC andκFLC were detected by indirect immunofluorescence.Furthermore, we observed the renal pathological changes by light microscope.TheλFLC andκFLC were determined through ELISA.Univariate analysis was used to examine the relationships between FLCs and clinical indicators and renal pathological changes of DN.Results The experiment group had higher hsCPR and Hcy level than the control group（P〈0.05）.The levels of cFLC（The sum ofλFLC andκFLC）in the experiment group were higher compared with the control group（P〈0.05）.The Hcy and hs-CRP were positively correlated with combined free light chain（cFLC）（P〈0.05）.The scores of tubulointerstitial lesions showed positive correlations（P〈0.05）with cFLC,but negatively correlated with eGFR（P〈0.05）.Conclusion The level of cFLC could be a predictor of the risk of mortality（especially cardiovascular disease caused）of DN patients and the progression of DN.