Carol Davila University of Medicine and Pharmacy, Bucharest, Romania.
Am J Kidney Dis. 2010 Apr;55(4):639-47. doi: 10.1053/j.ajkd.2009.10.043. Epub 2010 Jan 15.
Information about iron stores and their relationship with transferrin saturation (TSAT), serum ferritin, and the erythropoietic response to iron therapy is scarce in anemic non-dialysis-dependent patients with chronic kidney disease (CKD). We examined the diagnostic utility of peripheral-iron indices and the erythropoietic response to intravenous iron as indices of iron store depletion using bone marrow iron as a reference test in anemic non-dialysis-dependent patients with CKD.
Diagnostic test study.
SETTING & PARTICIPANTS: 100 anemic (hemoglobin <11 g/dL) patients with CKD stages 3-5, not receiving epoetin and iron.
TSAT index and serum ferritin level at baseline and increase in hemoglobin level 1 month after 200 mg of iron sucrose daily for 5 days.
Bone marrow iron (assessed using aspiration and Perls' stain), depleted versus replete, at baseline.
Area under the receiver operating characteristic curve (AUROC), sensitivity, and specificity of peripheral-iron indices and erythropoietic response to describe bone marrow iron stores.
Bone marrow iron stores were depleted in 48% of patients at baseline. In iron-depleted versus -replete subjects, mean hemoglobin level, median TSAT index, median serum ferritin level, and hemoglobin level increase after iron sucrose administration were 8.74 +/- 1.1 (SD) versus 9.22 +/- 0.9 g/dL (P = 0.02), 19% (interquartile range [IQR], 15%) versus 28% (IQR, 12%; P < 0.001), 100 (IQR, 131) versus 220 ng/mL (IQR, 213; P < 0.001), and 1.2 +/- 0.4 versus 0.8 +/- 0.3 g/dL (P < 0.001), respectively. TSAT, ferritin level, and increase in hemoglobin level AUROCs were similar: 0.75 (95% CI, 0.66-0.85), 0.76 (95% CI, 0.66-0.85), and 0.74 (95% CI, 0.65-0.84), respectively.
Bone marrow iron as the index of iron stores.
Half the anemic patients with CKD stages 3-5 had depleted iron stores. Peripheral-iron indices and erythropoietic response had equivalent, but limited, utility in identifying depletion of bone marrow iron stores. Use of these indices to indicate depletion of iron stores should be reconsidered.
关于铁储存量及其与转铁蛋白饱和度（TSAT）、血清铁蛋白和铁治疗的红细胞生成反应之间的关系，在非透析依赖的慢性肾脏病（CKD）患者中，贫血且铁蛋白水平正常的患者中相关信息十分匮乏。我们使用骨髓铁作为参考测试，检测了外周铁指标在评估铁储存量耗竭方面的诊断效用以及静脉铁治疗的红细胞生成反应，以此来评估非透析依赖的 CKD 患者的铁储存量耗竭情况。
诊断性测试研究。
100 名贫血（血红蛋白 <11 g/dL）、处于 CKD 3-5 期、未接受促红细胞生成素和铁剂治疗的患者。
基线时的 TSAT 指数和血清铁蛋白水平，以及在连续 5 天每天接受 200 mg 蔗糖铁后 1 个月时血红蛋白水平的升高。
基线时使用骨髓抽吸和 Perls 染色评估骨髓铁（铁耗尽或铁储备充足）。
接收者操作特征曲线（ROC）下面积（AUROC）、外周铁指标和铁治疗后红细胞生成反应对描述骨髓铁储存的敏感性和特异性。
在基线时，48%的患者骨髓铁储存量耗尽。与铁储备充足的患者相比，铁储备不足的患者的平均血红蛋白水平、中位数 TSAT 指数、中位数血清铁蛋白水平和蔗糖铁治疗后血红蛋白水平的升高分别为 8.74 +/- 1.1（SD）与 9.22 +/- 0.9 g/dL（P = 0.02）、19%（四分位距 [IQR]，15%）与 28%（IQR，12%；P < 0.001）、100（IQR，131）与 220 ng/mL（IQR，213；P < 0.001）以及 1.2 +/- 0.4 与 0.8 +/- 0.3 g/dL（P < 0.001）。TSAT、铁蛋白水平和血红蛋白水平升高的 AUROC 相似：分别为 0.75（95%CI，0.66-0.85）、0.76（95%CI，0.66-0.85）和 0.74（95%CI，0.65-0.84）。
骨髓铁作为铁储存的指标。
一半处于 CKD 3-5 期的贫血患者铁储存量不足。外周铁指标和铁治疗后的红细胞生成反应在识别骨髓铁储存量不足方面具有同等但有限的作用。使用这些指标来指示铁储存量不足的情况应该重新考虑。
