Luján Pablo, Chiurchiu Carlos, Capra Raúl, de Arteaga Javier, de la Fuente Jorge, Douthat Walter
Laboratorio de Bioquímica Clínica, Hospital Privado Universitario de Córdoba, Córdoba, Argentina.
Servicio de Nefrología, Hospital Privado Universitario de Córdoba y Carrera de posgrado de Nefrología, Universidad Católica de Córdoba, Córdoba, Argentina.
Nefrologia (Engl Ed). 2021 Mar-Apr;41(2):191-199. doi: 10.1016/j.nefroe.2020.07.002. Epub 2021 May 14.
Long-term consequences associated with kidney donation are controversial. Pre- and post-donation glomerular filtration rates (GFRs) are determinants of renal and cardiovascular risk weighting. In Latin America, there is limited experience in evaluating kidney function using GFR measurement techniques in kidney donors. The MDRD 4-variable and CKD-EPI equations are considered reasonable options. The objective of this study was to evaluate the performance of the MDRD and CKD-EPI equations in post-nephrectomy GFR dynamics in kidney donors.
A prospective cohort study with GFR measurement and estimation in 189 kidney donors who underwent nephrectomy between 2007 and 2016 at the Hospital Privado Universitario de Córdoba [Private University Hospital of Córdoba] in Córdoba, Argentina. GFRs were evaluated before and after nephrectomy by iothalamate clearance determined by HPLC and by the MDRD and CKD-EPI equations for estimating GFR. Two groups were formed for this study: Group 1 (n=107), with an evaluation time subsequent to GFR stabilization (3 months) of up to 5 years, and Group 2 (n=82), with an evaluation time of 5-10 years following donation. Measured GFR (mGFR) was assessed by iothalamate clearance determined by HPLC.
Renal compensation values were 61.9% (52.0%-71.1%) and 75.6% (64.9%-84.4%) for Group 1 (n=107) and Group 2 (n=82), respectively. MDRD underestimated the GFR in 3.2% (90ml/min/1.73m) and 38.6% (60ml/min/1.73m) compared to the mGFR, and CKD-EPI underestimated the GFR in 2.6% (90ml/min/1.73m) and 13.8% (60ml/min/1.73m). Diagnostic performance was evaluated with a ROC curve (mGFR<60ml/min/1.73m) for MDRD (ABC=0.66; CI: 0.59-0.73; sensitivity: 98.7%; specificity: 63.3%) and for CKD-EPI (ABC=0.79 CI: 0.73-0.85; sensitivity: 96.9%; specificity: 76.4%. Estimated GFR (eGFR) showed poor performance for estimating the glomerular filtration rate in the post-nephrectomy follow-up of donors over 50 years of age.
Equations for estimating GFRs showed poor performance for long-term follow-up of post-nephrectomy GFRs. Measuring GFRs to determine kidney function is recommended in the screening and follow-up of some donors under the current selection criteria.
肾捐赠的长期后果存在争议。捐赠前后的肾小球滤过率（GFR）是肾脏和心血管风险权重的决定因素。在拉丁美洲，使用GFR测量技术评估肾捐赠者肾功能的经验有限。MDRD 4变量方程和CKD-EPI方程被认为是合理的选择。本研究的目的是评估MDRD和CKD-EPI方程在肾切除术后肾捐赠者GFR动态变化中的表现。
一项前瞻性队列研究，对2007年至2016年期间在阿根廷科尔多瓦市的科尔多瓦私立大学医院接受肾切除术的189名肾捐赠者进行GFR测量和估算。通过HPLC测定碘他拉酸盐清除率以及使用MDRD和CKD-EPI方程估算GFR，在肾切除术前和术后评估GFR。本研究分为两组：第1组（n = 107），评估时间为GFR稳定（3个月）后长达5年；第2组（n = 82），评估时间为捐赠后5 - 10年。通过HPLC测定碘他拉酸盐清除率评估实测GFR（mGFR）。
第1组（n = 107）和第2组（n = 82）的肾脏代偿值分别为61.9%（52.0% - 71.1%）和75.6%（64.9% - 84.4%）。与mGFR相比，MDRD在GFR≥90ml/min/1.73m时低估了3.2%，在GFR＜60ml/min/1.73m时低估了38.6%；CKD-EPI在GFR≥90ml/min/1.73m时低估了2.6%，在GFR＜60ml/min/1.73m时低估了13.8%。使用ROC曲线（mGFR＜60ml/min/1.73m）评估诊断性能，MDRD的曲线下面积（ABC）= 0.66；95%置信区间（CI）：0.59 - 0.73；灵敏度：98.7%；特异性：63.3%；CKD-EPI的ABC = 0.79，CI：0.73 - 0.85；灵敏度：96.9%；特异性：76.4%。在50岁以上捐赠者的肾切除术后随访中，估算GFR（eGFR）在估算肾小球滤过率方面表现不佳。
估算GFR的方程在肾切除术后GFR的长期随访中表现不佳。在当前选择标准下，建议在某些捐赠者的筛查和随访中测量GFR以确定肾功能。
