Abstract: Objective To improve microcolumn agglutination test,then discuss the effects on early detection of HDN.Methods The microcolumn agglutination test was improved from the aspects of reaction time（15min,30min）,cell concentration（0.5%,1%）,treatment of cell reagent（low ionic strength salt solution,papain） and serum cell ratio（2∶1,4∶1）,respectively. Second,The simulation experiment was carried out by using IgG anti -D reagent,and the best scheme was found by the range analysis method. Three hemolysis experiment were carried out for the 90 cases of suspected HDN send from obstetric. Tossing in test was using thermal radiation method. Classic antiglobulin test （control group） and improved microcolumn agglutination test （experimental group） were used respectively for free trials and radiation test. Finally,statistical methods were used to compare the two methods.Results ①The optimal detection scheme of improved microcolumn agglutination test was the reaction time of 30 min,the cell concentration 1.0 %,the treatment of cell reagent papain,and the proportion of serum and cell 2∶1,among them cell reagents had the greatest impact on detection results. ②In the 90 suspected HDN cases,36 cases were diagnosed as HDN,21 cases of type A,15 cases of type B. There was no statistically significant difference in different type of HDN（χ²=0.008,P=0.931）. ③The positive rates of improved microcolumn agglutination test were higher than classical antiglobulin test（χ²=3.988,P=0.046; χ²=4.261,P=0.039）. It showed that improved microcolumn agglutination test was better than classical antiglobulin test for the early detection of HDN.Conclusion sThe best experimental scheme of improved microcolumn agglutination test was reaction time 30 min,cell concentration 1.0 %,treatment of cell reagent papain,and the proportion of serum and cell 2∶1. The improved microcolumn agglutination test was better than classical antiglobulin test for the detection of HDN,which could provide more reliable test basis for early diagnosis.

Key words: Improved microcolumn agglutination test, Classical antiglobulin test, HDN detection