Gao Mei-zhe, Li Hai-qi
Department of Child Health Care, Children's Hospital, Chongqing University of Medical Sciences, Chongqing 400014, China.
Zhonghua Er Ke Za Zhi. 2006 Jan;44(1):7-10.
To explore the levels of serum vitamin B(12) (VB(12)) in preschool children, determine the relationship between the levels of serum VB(12) and anemia, and analyze the effects of several factors related to the level of serum VB(12).
From March 2005 to July 2005, the weight, height and complete blood count (CBC) were studied in 351 children aged 2 to 7 years from 4 kindergartens of Chongqing. The concentrations of serum VB(12) and the dietary survey of 177 of the children were evaluated.
The average level of serum VB(12) for the preschool children was 552 pg/ml. The levels of serum VB(12) in 4.5% (8/177) of the children were below 200 pg/ml (defined as VB(12) deficiency), in 10.7% (19/177) of the children were 200 - 300 pg/ml (called marginal deficiency). There were no significant differences in the levels of serum VB(12) between boys and girls. And there was no correlation between the levels of serum VB(12) and hemoglobin. The results of multivariate stepwise regression analysis showed that the concentrations of serum VB(12) were mainly influenced by the contents of VB(12) in the foods (P = 0.03). Eight of the children with normal growth and development were diagnosed as VB(12) deficiency, only one of them was diagnosed microcytic hypochromatic anemia. The ranges of Hb, MCV and MHC were normal in the other 7 children.
The levels of serum VB(12) of preschool children were higher than that of adults, suggesting that the levels of serum VB(12) change with age. There were no significant differences in the levels of serum VB(12) in 2-7 years old children between sex and ages. The levels of serum VB(12) were not correlated with the concentrations of hemoglobin. Macrocytic anemia may not occur in preschool children with VB(12) deficiency. The intake of VB(12) from the diets was one of the important factors for preschool children to keep the normal ranges of serum VB(12). It is beneficial for children to consume foods enriched with VB(12) to keep the normal level of serum VB(12).
探讨学龄前儿童血清维生素B12（VB12）水平，确定血清VB12水平与贫血之间的关系，并分析与血清VB12水平相关的几个因素的影响。
2005年3月至2005年7月，对来自重庆4所幼儿园的351名2至7岁儿童的体重、身高和全血细胞计数（CBC）进行了研究。对其中177名儿童的血清VB12浓度和饮食情况进行了评估。
学龄前儿童血清VB12的平均水平为552 pg/ml。4.5%（8/177）的儿童血清VB12水平低于200 pg/ml（定义为VB12缺乏），10.7%（19/177）的儿童血清VB12水平为200 - 300 pg/ml（称为边缘性缺乏）。男孩和女孩的血清VB12水平无显著差异。血清VB12水平与血红蛋白之间无相关性。多因素逐步回归分析结果显示，血清VB12浓度主要受食物中VB12含量的影响（P = 0.03）。8名生长发育正常的儿童被诊断为VB12缺乏，其中仅1名被诊断为小细胞低色素性贫血，其余7名儿童的血红蛋白（Hb）、平均红细胞体积（MCV）和平均血红蛋白含量（MHC）范围均正常。
学龄前儿童血清VB12水平高于成年人，提示血清VB12水平随年龄变化。2至7岁儿童血清VB12水平在性别和年龄方面无显著差异。血清VB12水平与血红蛋白浓度无关。VB12缺乏的学龄前儿童可能不会发生大细胞性贫血。从饮食中摄入VB12是学龄前儿童维持血清VB12正常范围的重要因素之一。食用富含VB12的食物对儿童维持血清VB12正常水平有益。
