What procedure should be performed next when screening cells, major crossmatch, autocontrol, and DAT (anti-IgG) are all positive?

When faced with a situation where screening cells, major crossmatch, autocontrol, and directantiglobulin test (DAT) with anti-IgG are all positive, it is essential to determine the specificity of the antibody causing these results. Performing an elution followed by a cell panel on the eluate helps to identify the specific antibodies present in the patient's serum.

Elution is the process of releasing the bound antibodies from the red blood cells that are coated in vivo, which is exactly what the positive DAT indicates. Once the antibodies are eluted, you can use a cell panel to test against a variety of red blood cell antigens. This approach allows for the identification of the specific anti-red cell antibodies responsible for the positive tests.

This strategy is crucial for appropriate patient management, especially before transfusions, as it helps to ensure that the patient receives compatible blood products and avoids hemolytic reactions. The other options may contribute to the investigation of the patient's serological profile but are not as directly suited to addressing the immediate need to clarify the cause of positive screening results and resolving potential transfusion difficulties.