Which method is not approved for leukocyte reduction of red blood cells?

Leukocyte reduction of red blood cells is an important process aimed at minimizing the risk of transfusion-related complications, particularly in immunocompromised patients. The method that is not approved for leukocyte reduction is the removal of the buffy coat. This option is not sanctioned as an effective or reliable means of achieving adequate leukocyte reduction.

The buffy coat, which consists of white blood cells and platelets, can be present in red blood cell units. While its removal may seem like a logical method for reducing leukocytes, it does not consistently ensure a sufficient reduction in white blood cell content. The process can lead to variability in the efficiency of leukocyte removal, which is why regulatory agencies do not endorse it as an approved method.

In contrast, other methods like prestorage filtration, bedside filtration, and poststorage filtration are established practices that have demonstrated effectiveness in reducing leukocyte counts in red blood cell units. These methods involve specific filtration techniques that reliably capture and remove leukocytes while preserving the red blood cells. Hence, they are recognized as safer and more standardized approaches for leukocyte reduction in transfusions.