King L, Reid M, Forrester T E
Sickle Cell Unit, Tropical Medicine Research Institute, The University of the West Indies, Kingston, Jamaica.
West Indian Med J. 2005 Oct;54(5):292-6. doi: 10.1590/s0043-31442005000500004.
The aim of this study was to determine, using a combination of measures, the prevalence of iron deficiency anaemia (IDA) in children under five years-of-age who have sickle cell disease (SCD) and attend the Sickle Cell Clinic (SCU) of the Tropical Medicine Research Institute.
Children with homozygous sickle cell anaemia (Hb SS) or doubly heterozygous for Hb S and Hb C (Hb SC) disease who had not received a blood transfusion within three months prior to the iron measurements, were enrolled. The diagnosis of IDA was made if transferrin saturation was less than 16% with serum iron less than 10.7 micromol/l and a low mean corpuscular volume (MCV) for age.
Twelve children (8.5%), seven with Hb SS and five with Hb SC had IDA. Adjusting for genotype, children with IDA had significantly higher red blood cell (RBC) counts (4.3 x10(9)/l vs 3.0 x 10(9)/l, p < 0.001) and total iron binding capacity (TIBC) (65.6 micromol/l vs 55.2 micromol/l, p < 0.004) but significantly lower reticulocyte (retic) counts (7.8 % vs 12.2%, p = 0.001) than children without IDA.
Iron deficiency anaemia is a clinical problem which affects children with SCD in Jamaica. The higher RBC counts in the IDA group may be due to decreased haemolysis and increased red cell survival whilst the lower reticulocyte counts may be due to impaired erythropoiesis. These observations need to be extended by clinical studies to establish improved diagnostic measures for IDA in SCD. Additionally, clinical trials are needed to determine whether treatment of IDA in children with SCD reduces morbidity and is associated with clinical benefits such as improvements in neurocognitive function.
本研究旨在通过综合多种测量方法,确定患有镰状细胞病(SCD)并在热带医学研究所镰状细胞诊所(SCU)就诊的五岁以下儿童中铁缺乏性贫血(IDA)的患病率。
纳入在进行铁测量前三个月内未接受过输血的纯合子镰状细胞贫血(Hb SS)或Hb S与Hb C双重杂合子(Hb SC)疾病患儿。如果转铁蛋白饱和度低于16%,血清铁低于10.7微摩尔/升且年龄对应的平均红细胞体积(MCV)较低,则诊断为IDA。
12名儿童(8.5%)患有IDA,其中7名Hb SS患儿和5名Hb SC患儿。在调整基因型后,患有IDA的儿童红细胞(RBC)计数(4.3×10⁹/升对3.0×10⁹/升,p<0.001)和总铁结合力(TIBC)(65.6微摩尔/升对55.2微摩尔/升,p<0.004)显著更高,但网织红细胞(retic)计数(7.8%对12.2%,p = 0.001)显著低于未患IDA的儿童。
铁缺乏性贫血是一个影响牙买加SCD患儿的临床问题。IDA组较高的RBC计数可能是由于溶血减少和红细胞存活增加,而较低的网织红细胞计数可能是由于红细胞生成受损。这些观察结果需要通过临床研究加以扩展,以建立SCD中IDA的改进诊断措施。此外,需要进行临床试验,以确定SCD患儿的IDA治疗是否能降低发病率,并与神经认知功能改善等临床益处相关。