What is the primary purpose of crossmatching before a neonatal blood transfusion?

• A. To assess donor's infectious disease status.
• B. To ensure ABO/Rh compatibility between donor and recipient.
• C. To check donor's vitamin K status.
• D. To measure transfusion-related bilirubin.

Answer: (B)

Crossmatching before a neonatal transfusion focuses on safety of the transfused red blood cells by confirming that the recipient’s antibodies will not attack donor cells. In newborns, maternal antibodies can be present in the infant and may react with donor ABO/Rh antigens, so verifying compatibility helps prevent a hemolytic transfusion reaction. The infectious status of the donor is checked separately through donor screening, not via crossmatching; vitamin K status is unrelated to compatibility testing; and bilirubin levels are watched after transfusion to monitor for hemolysis, not to determine compatibility.