Comparison of ABO isoagglutinin titres by three different methods: tube haemagglutination, micro-column agglutination and automated immunohematology analyzer based on erythrocyte-magnetized technology.

Background and Objectives ABO isoagglutinin titre is important for evaluating and monitoring ABO-incompatible (ABOi) stem cells or solid organ transplantations. There are several methods to measure the titre level, including the tube haemagglutination method, micro-column agglutination and erythrocyte-magnetized technology (EMT). However, few studies have reported isoagglutinin measured by EMT. Here, we compared the isoagglutinin titre of normal individuals obtained by an automated instrument with that obtained by conventional manual methods to evaluate the feasibility of replacing the manual method with the automated instrument. Materials and Methods The ABO isoagglutinin titre was measured on residual samples of healthy individuals who visited the health promotion centre of the National Cancer Center, Korea, from April to October 2015. Samples from 120 patients were collected, which included 20 males and 20 females for each blood group (A, B and O). IgM and IgG ABO isoagglutinin titres of each blood group were measured by the tube haemagglutination, micro-column agglutination and EMT techniques. The median (minimum-maximum) titres were compared, and the concordance between two methods was evaluated with the rate of results showing within one titre difference. Results The median ABO IgM and IgG titres of all blood groups obtained by the EMT method were higher than that obtained by the conventional tube haemagglutination and micro-column agglutination. Conclusion The agreement between the two methods was comparable in case of IgM but low in IgG.