眼结膜印迹细胞法在维生素A缺乏早期筛查中评价标准的探讨

Criteria for evaluation of conjunctival impression cytology (CIC) in early screening of vitamin A deficiency

目的探讨眼结膜印迹细胞法(CIC)在儿童维生素A缺乏(VAD)早期筛查中的评价标准。方法采用CIC法对3～7岁学龄前儿童进行维生素A营养状况评价,研究结膜印迹细胞形态学改变及相应的血清维生素A水平,以确定评价标准。结果CIC法0～1级可见杯状细胞和正常的上皮细胞,2级只见正常上皮细胞而未见杯状细胞,3～5级仅见异常上皮细胞。随着结膜印迹细胞异常程度的增加,血清维生素A水平相应降低,二者呈负相关(r=-0.824,P<0.05),其中结膜印迹细胞0～1级组和2级组的血清维生素A均值>300μg/L(P<0.05)。结论CIC法评价机体维生素A营养状况采用包括正常水平、临界水平和异常水平的三级标准法比较合适。

Objective To make objective criteria for evaluation of conjunctival impression cytology （CIC） in early screening of vitamin A deficiency （VAD） in children. Methods The status of vitamin A in children aged 3-7 years old was evaluated with CIC method. In order to justify the judgemental criterion of CIC, the changes in CIC and the levels of serum vitamin A were studied. Results Goblet cells and normal epithelial cells could be found in grade 0-1 of CIC; only normal epithelial cells without Goblet cells could be seen in grade 2 of CIC, and only abnormal epithelial cells were identified in grade 3-5 of CIC. Along with the increasing degree of abnormalify of CIC, the levels of serum vitamin A decreased accordingly （r= -0. 824, P〈0105）, and the average value of serum vitamin A in both grade 0-1 and grade 2 groups was higher than 300μLg/L （P〈0.05）. Conclusion The three-grade criterion is the more appropriate one for CIC to assess children＇s status of vitamin A reserve, including normal level, marginal level and abnormal level.