What can happen if a blood specimen is collected from a previously transfused patient?

Collecting a blood specimen from a previously transfused patient can lead to the presence of antibodies in the blood. These antibodies are produced as part of the immune response to the transfused blood, which may come from different blood types or contain foreign antigens. The presence of these antibodies can interfere with various blood test results, particularly those related to blood typing, crossmatching, and certain immune assays.

For instance, if the lab performs tests that assess the compatibility of blood for transfusions or looks for specific antigens, the antibodies present could lead to false positives or negatives, complicating diagnosis and treatment. Therefore, it is crucial to consider the patient’s transfusion history when interpreting results to ensure accurate clinical decision-making.

The other options suggest alternative impacts on blood tests, but they do not accurately relate to the implications of collecting from transfused individuals.