Which of the following statements about ABO incompatible transfusion reactions is true?

The statement that symptoms of ABO incompatible transfusion reactions may sometimes remain unnoticed until after the transfusion is accurate because not all reactions manifest immediately or dramatically. In some cases, patients may not show overt signs during the transfusion process, and symptoms can develop progressively post-transfusion. This can include subtle signs that might be overlooked or misattributed to other causes, which can delay recognition and management of the transfusion reaction.

Understanding that symptoms may not always be immediately evident underscores the importance of monitoring patients both during and after blood transfusions for any potential adverse reactions, regardless of how mild they may seem at first. This awareness helps in ensuring patient safety and prompt intervention if a reaction does occur.