肾组织病理积分联合肾衰竭风险方程在预测中晚期IgA肾病进展风险中的应用

Adding MEST⁃C score to the kidney failure risk equation improved risk prediction in advanced IgA nephropathy

目的探讨在肾衰竭风险方程(KFRE)基础上,增加肾组织病理积分(MEST⁃C)能否进一步提高中晚期IgA肾病进展风险的预测效能,改善该类疾病的进展风险分层。方法前瞻性队列研究,共纳入205例基线eGFR 15~59 mL/(min·m2)原发性IgA肾病患者,按临床诊疗常规每1~3个月随访1次肾功能。全部病例按4变量/8变量KFRE计算2年终末期肾脏病(ESRD)进展风险。每个病例的活检肾组织由独立病理医生按国际指南中的IgA肾病牛津病理分型(MEST⁃C)进行分级。ESRD定义为需接受维持性透析治疗或接受肾移植。采用AUC、NRI等指标评估KFRE和MEST⁃C单独或联合对中晚期IgA肾病2年内进展至ESRD的预测效能和风险分层改善度。结果205例患者中,共38例(18.5%)在2年内进入ESRD终点。4变量KFRE预测中晚期IgA肾病进展风险的AUC为0.81(95%CI:0.73~0.89),8变量KFRE预测效能AUC为0.79(95%CI:0.71~0.87),MEST⁃C预测效能AUC 0.74(95%CI:0.64~0.83)。增加MEST⁃C至4变量KFRE进一步提高总体AUC至0.85(95%CI:0.78~0.91),且能显著改善中晚期IgA肾病2年内进入ESRD风险分层(NRI 0.47,P=0.006)。结论4变量KFRE预测中晚期IgA肾病进展风险效能良好,增加肾组织病理分级MEST⁃C有助于进一步提高预测效能,改善IgA肾病进展至ESRD的风险分层。

Objective To investigate whether adding renal histological score(MEST⁃C)to the Kidney Failure Risk Equation(KFRE)could improve predicting the risk of progression in advanced IgA nephropathy.Methods This was a prospective cohort study in which 205 patients with advanced IgA nephropathy[15~59 mL/(min·m2)]were enrolled and followed up to 2 years.The timepoint of renal biopsy was defined as baseline.The 4⁃variable/8⁃variable KFRE was used to estimate 2⁃year risk of progression to end stage renal disease(ESRD,defined as need for receiving maintenance dialysis or renal transplantation).AUCs were calculated to evaluate the performance of risk prediction using KFRE and MEST⁃C alone or in combination.Risk classification for progression to ESRD was assessed by net reclassification index(NRI)and integrate discrimination index(IDI).Results Among 205 patients with advanced IgA nephropathy,38(18.5%)progressed to ESRD within 2 years of follow up.The 4⁃variable KFRE predicted the progression of advanced IgA nephropathy with an AUC of 0.81(95%CI:0.73~0.89),while the 8⁃variable KFRE with an AUC of 0.79(95%CI:0.71⁃0.87),the MEST⁃C with an AUC of 0.74(95%CI:0.64~0.83).Adding MEST⁃C to the 4⁃variable KFRE produced an overall AUC of 0.85(95%CI:0.78~0.91)and significant improvement for risk classification for ESRD(NRI,0.47 and IDI 0.05).Conclusion Adding renal histological score to the Kidney Failure Risk Equation improved risk prediction and reclassification of progression to ESRD in patients with advanced IgA nephropathy.