In the context of positive DAT results from a recently transfused patient, which procedure is most appropriate for identifying the antibody?

A positive Direct Antiglobulin Test (DAT) indicates the presence of antibodies or complement bound to the surface of red blood cells, which can occur as a result of a transfusion reaction. In this scenario, the most appropriate procedure for identifying the antibody is elution followed by a panel on the eluate.

This approach is effective because elution allows for the recovery of antibodies from the patient’s red blood cells, isolating the antibodies that are causing the positive DAT. Once the antibodies are eluted, testing the eluate against a panel of known red blood cells can help determine the specific antibody involved. The panel will show the reactivity pattern of the eluted serum, thus allowing for the identification of the specific antibody.

Other methods, while useful in different contexts, may not be as effective in this scenario. For instance, adsorption might not be ideal as it could potentially mask the antibody we are trying to identify. An enzyme panel is valuable but is used to enhance or define antibody specificity rather than to identify the initial cause of a positive DAT in the presence of recent transfusion. Antigen typing the patient’s red cells could provide information about the patient's blood group and potential alloantibodies but does not focus directly on identifying the antibody