Yuzbasiyan-Gurkan V A, Brewer G J, Vander A J, Guenther M J, Prasad A S
Department of Human Genetics, University of Michigan Medical School, Ann Arbor 48109-0618.
Am J Hematol. 1989 Jun;31(2):87-90. doi: 10.1002/ajh.2830310203.
Zinc deficiency is a significant clinical finding in sickle cell anemia (SCA) and abnormalities of zinc handling such as hyperzincuria are present. The cause of increased urinary zinc excretion in SCA is not clear. To define the renal handling of zinc in SCA and in healthy subjects, we measured zinc (total and ultrafilterable plasma zinc, urine zinc) and creatinine clearance in eight healthy and seven SCA subjects. Ultrafilterable zinc in plasma was assessed by equilibration of plasma with 65Zn followed by filtration through Amicon Cetriflo CF25 cones. While the mean filtered load of zinc was not significantly different between the two groups, the mean zinc excretion rate was approximately three-fold higher in patients (1.73 +/- 0.96 vs. 0.63 +/- 0.39 micrograms/min, P less than .05). In controls, zinc excreted was significantly less than zinc filtered (P less than .005), the fractional excretion of zinc averaging 0.49 +/- 0.31, indicating net reabsorption. This was not the case for the SCA patients. We conclude that there is impaired renal tubular handling of zinc in SCA.
锌缺乏是镰状细胞贫血（SCA）的一项重要临床发现，且存在锌代谢异常，如高锌尿症。SCA患者尿锌排泄增加的原因尚不清楚。为了明确SCA患者和健康受试者的肾脏对锌的处理情况，我们测量了8名健康受试者和7名SCA患者的锌（总血浆锌和可超滤血浆锌、尿锌）及肌酐清除率。通过使血浆与65Zn平衡，然后通过Amicon Cetriflo CF25滤器过滤来评估血浆中的可超滤锌。虽然两组之间锌的平均滤过量没有显著差异，但患者的平均锌排泄率约为健康受试者的三倍（1.73±0.96对0.63±0.39微克/分钟，P<0.05）。在对照组中，排泄的锌明显少于滤过的锌（P<0.005），锌的分数排泄平均为0.49±0.31，表明存在净重吸收。SCA患者的情况并非如此。我们得出结论，SCA患者存在肾小管对锌的处理受损。
