红细胞参数中 MCH 指标筛查地中海贫血比 MCV 指标更可靠

目的：对红细胞指标红细胞平均体积（MCV）和红细胞平均血红蛋白（MCH）筛查地贫的可靠性进行比较。方法将一份 MCV 处于临界值的新鲜静脉血于1 d 内送到珠海市21家医疗机构进行全血细胞分析，然后统计分析得出室间和室内MCV 和 MCH 的变异系数（CV）和偏倚值。此外，另抽取 EDTA 抗凝静脉血10份，一分为二，观察温度和放置时间对此两个指标的影响。结果该市室间 MCV 的 CV 值（4．1％）明显大于 MCH 的 CV 值（2．8％），MCH 检测结果的合格率（100％）明显高于MCV（66．7％）（P ＜0．05）。全血标本在两种温度条件（室温与冷藏）下保存72 h，MCH 指标变化不大（P ＞0．05）。血液标本冷藏72 h 时，MCV 与即测值比较差异无统计学意义（P ＞0．05），室温保存48 h时，MCV 显著升高（P ＜0．05）。在室温和冷藏保存48 h时，两者的 MCV 差异有统计学意义（P ＜0．05）。结论在室间以及在不同温度保存的条件下，MCH 指标较 MCV 重复性好且更稳定，MCH 指标作为临床一线地贫筛查指标比 MCV 指标更可靠。

More reliable erythrocyte parameter MCH than MCV for screening thalassaemia trait

Objective To compare the reliability of erythrocyte parameter mean corpuscular volume（MCV）and mean corpuscu-lar hemoglobin（MCH）for screening thalassaemia trait.Methods A fresh venous blood sample with the cut-off value of MCV was sent to 21 hospitals of Zhuhai city for conduct the full blood cell analysis within 1 d.Then the inter-and intra-coefficient of varia-tion （CV）as well as bias values of MCV and MCH were calculated and compared.In addition,10 EDTA-anticoagulant venous blood samples were divided into two parts,the effects of stored temperature and time on MCV and MCH were observed.Results The coefficient of variation（CV）of MCV （4.1%）was significantly greater than that of MCH （2.8%）among 21 laboratories,the qualification rate of MCH detection results was 100%,which was significantly higher than 66.7% of MCV （P 〈0.05）.When the whole blood samples were stored under 2 kinds of the temperature condition（room temperature and refrigeration）for 72 h,MCH changed little （P 〉0.05）.When these samples were stored under the refrigerated condition for 72 h,MCV had no statistically sig-nificant difference compared with the instant detection results of MCV （P 〉0.05）,when stored at the room temperature for 48 h, MCV was significantly increased （P 〈0.05）,MCV had statistical difference in storage for 48 h between the room temperature and the refrigeration.Conclusion Among laboratories and under different temperature conditions,the reproducibility of MCH is better than that of MCV and is more stable than MCV.MCH as the clinical first-line screening for thalassaemia is more reliable than MCV.