Regional Unit of Rheumatology and Osteoporosis, Central Hospital Dr. Ignacio Morones Prieto and Faculty of Medicine, Universidad Autónoma de San Luis Potosí, Carranza 2395, 78240 San Luis Potosí, México.
Rheumatol Int. 2012 Aug;32(8):2293-9. doi: 10.1007/s00296-011-1940-9. Epub 2011 May 21.
Few studies have evaluated the glomerular filtration rate (GFR) in patients with systemic lupus erythematosus (SLE). Even though the National Kidney Foundation (NKF) suggests using the equations to estimate GFR, rheumatologists continue using creatinine clearance (CCl). The main objective of our study was the assessment of different equations to estimate GFR in patients with SLE: Simplified MDRD study equation (sMDRD), CCl, Cockcroft Gault (CG), CG calculated with ideal weight (CGi), Mayo Clinic Quadratic (MCQ), and Chronic Kidney Disease Epidemiology Collaboration Equation (CKD-EPI). CKD-EPI was considered as the reference standard, and it was compared with the other equations to evaluate bias, correlation (r), sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), percentage of measurement of GFR between 70-130% of GFR measured through CKD-EPI (P30) and to compute the ROC curves. Adequacy of the 24-h urine collection was evaluated. To classify patients into GFR < 60 ml/min/1.73 m(2), the best sensitivity and NVP were obtained with sMDRD: the best PPV and specificity with MCQ. P30 was 99.3% with sMDRD, 77.5% CCl, 91.7% CG, 96.7% CGi, and 77.2% with MCQ. The lowest bias was for sMDRD and the highest for CCl. Only 159 (52.6%) urine collections were considered adequate, and when these patients were re-evaluated, the statistical results improved for CCl. CGi was better in general than CG. CCl should not be considered as an adequate GFR estimation. Ideal weight is better than real weight to calculate GFR through CG in patients with SLE.
很少有研究评估系统性红斑狼疮（SLE）患者的肾小球滤过率（GFR）。尽管美国国家肾脏病基金会（NKF）建议使用方程来估计 GFR，但风湿病学家仍继续使用肌酐清除率（CCl）。我们研究的主要目的是评估不同的方程来估计 SLE 患者的 GFR：简化 MDRD 研究方程（sMDRD）、CCl、 Cockcroft-Gault（CG）、用理想体重计算的 CG（CGi）、Mayo 诊所二次方程（MCQ）和慢性肾脏病流行病学合作方程（CKD-EPI）。CKD-EPI 被认为是参考标准，并与其他方程进行比较，以评估偏差、相关性（r）、敏感性、特异性、阳性预测值（PPV）、阴性预测值（NPV）、通过 CKD-EPI 测量的 GFR 与 70-130%之间的 GFR 测量值之间的百分比（P30），并计算 ROC 曲线。评估了 24 小时尿液收集的充分性。为了将患者分类为 GFR <60 ml/min/1.73 m(2)，sMDRD 获得了最佳的敏感性和 NVP：MCQ 获得了最佳的 PPV 和特异性。sMDRD 的 P30 为 99.3%，CCl 为 77.5%，CG 为 91.7%，CGi 为 96.7%，MCQ 为 77.2%。sMDRD 的偏差最低，CCl 的偏差最高。只有 159 份（52.6%）尿液收集被认为是充分的，当对这些患者进行重新评估时，CCl 的统计结果有所改善。总体而言，CGi 优于 CG。CCl 不应该被认为是一种充分的 GFR 估计。在 SLE 患者中，用 CG 计算 GFR 时，理想体重优于实际体重。
