Which method is most helpful to confirm a weak ABO subgroup?

When confirming a weak ABO subgroup, adsorption-elution is particularly valuable because it allows for the identification of weaker antigen expression. This method helps in isolating the patient's red blood cells and treating them with specific antibodies, thereby removing the antibodies that may be present in the serum. The elution process then extracts any bound antibodies from the red blood cells, which can then be tested against known antigens to confirm the presence of weak subgroup antigens.

In weak ABO subgroups, the antigens may not be adequately expressed, leading to weaker reactions in standard serological tests. The adsorption-elution technique enhances the sensitivity of detecting these weak antigens by concentrating the specific antibodies and allowing for a clearer identification of the subgroup.

The effectiveness of this method makes it the preferred choice for confirming weak subgroup identifications. Other methods, while useful for various blood typing situations, may not provide the same level of specificity or sensitivity needed for confirming weak subgroups. For instance, testing with A1 lectin can help differentiate between A1 and A2 subgroups, but it may not provide confirmation for weaker subgroups. Similar limitations apply to neutralization and the use of anti-A,B in certain contexts, which may not enhance the detection of weak antigens as effectively as adsorption