Fishbane S, Galgano C, Langley R C, Canfield W, Maesaka J K
Winthrop University Hospital Division of Nephrology, Mineola, New York, USA.
Kidney Int. 1997 Jul;52(1):217-22. doi: 10.1038/ki.1997.323.
The assessment of iron status for hemodialysis patients has been hindered by the inaccuracy of commonly used diagnostic tests. A novel assay, the reticulocyte hemoglobin content (CHr), has recently been found to sensitively detect functional iron deficiency among nonuremic patients treated with recombinant erythropoietin (rHuEPO). The purpose of this study was to evaluate the CHr for the assessment of iron status in hemodialysis patients. One hundred sixty-four stable hemodialysis patients had a mean CHr of 27.5 +/- 2.8 pg with a normal distribution of values. The mean CH (mature red cell hemoglobin content) was 26.4 +/- 2.4 pg. There was a close correlation between CHr and CH (r = 0.86, P < 0.0001). A significant subgroup of patients (12.2%) had CHr values < CH. These patients had recent increases in rHuEPO dose, and a lower mean transferrin saturation and hematocrit, suggesting the recent onset of functional iron deficiency due to the increase in rHuEPO dose. In the second phase of the study, 32 patients were randomly selected to receive treatment with a single dose infusion of 1,000 mg of intravenous iron dextran (IVFe). Patients were classified as iron deficient (N = 7) if they responded with a significant reticulocytosis (sustained 1 basis point increase in corrected reticulocyte index within 2 weeks). All other patients were classified as iron replete (N = 25). A CHr < 26 pg at baseline predicted iron deficiency with a sensitivity of 100%, specificity of 80%. The serum ferritin, transferrin saturation and percentage of hypochromic red blood cells all were less accurate. The time to correction of iron deficiency at the level of the reticulocyte was found to be within 48 hours as measured by correction of the mean CHr to > 26 pg, and by the shift of the vast majority of the reticulocyte population to CHr > 26 pg within this time span. We conclude that CHr < 26 pg is an accurate measure of iron status in hemodialysis patients, that a CHr value < CH indicates the acute onset of iron deficiency, and that a single dose infusion of intravenous iron results in correction of iron deficiency at the level of the reticulocyte within 48 hours.
常用诊断测试的不准确性阻碍了对血液透析患者铁状态的评估。一种新的检测方法，即网织红细胞血红蛋白含量（CHr），最近被发现能灵敏地检测接受重组促红细胞生成素（rHuEPO）治疗的非尿毒症患者中的功能性缺铁。本研究的目的是评估CHr在血液透析患者铁状态评估中的作用。164例稳定的血液透析患者的CHr均值为27.5±2.8 pg，数值呈正态分布。平均CH（成熟红细胞血红蛋白含量）为26.4±2.4 pg。CHr与CH之间存在密切相关性（r = 0.86，P < 0.0001）。有一个显著的患者亚组（12.2%）的CHr值低于CH。这些患者近期rHuEPO剂量增加，平均转铁蛋白饱和度和血细胞比容较低，提示因rHuEPO剂量增加导致近期功能性缺铁的发生。在研究的第二阶段，随机选择32例患者接受单次静脉注射1000 mg右旋糖酐铁（IVFe）治疗。如果患者出现显著的网织红细胞增多（2周内校正网织红细胞指数持续增加1个基点），则被分类为缺铁（N = 7）。所有其他患者被分类为铁充足（N = 25）。基线时CHr < 26 pg预测缺铁的敏感性为100%，特异性为80%。血清铁蛋白、转铁蛋白饱和度和低色素红细胞百分比的准确性均较低。通过将平均CHr校正至> 26 pg以及在该时间段内绝大多数网织红细胞群体的CHr转移至> 26 pg来测量，发现网织红细胞水平的缺铁纠正时间在48小时内。我们得出结论，CHr < 26 pg是血液透析患者铁状态的准确指标，CHr值低于CH表明缺铁急性发作，并表明单次静脉注射铁剂可在48小时内网织红细胞水平纠正缺铁。
