Question

When should a weak D test always be performed?

1) When an Rh negative infant is born to an Rh positive mother
2) When an Rh negative infant is born to an Rh negative mother
3) When blood is received at the collection facility
4) On a patient anticipating a possible transfusion due to an upcoming surgery

Answer 1

A weak D test should be performed when an Rh negative infant is born to an Rh positive mother to prevent hemolytic disease of the newborn (HDN) by timely administration of Rho(D) immune globulin.

Step-by-step explanation:

A weak D test should always be performed when an Rh negative infant is born to an Rh positive mother. This situation is akin to when blood is received at a collection facility or on a patient anticipating a possible transfusion due to upcoming surgery. However, it is most critical when dealing with pregnancy and childbirth, as the presence of Rh antibodies can lead to hemolytic disease of the newborn (HDN), also known as erythroblastosis fetalis. HDN can cause severe anemia in the fetus or newborn, and might even lead to death if left untreated. Fortunately, the condition can be prevented by administering Rho(D) immune globulin to the Rh negative mother during pregnancy and shortly after childbirth, avoiding the formation of anti-D antibodies that could attack the red blood cells of an Rh positive fetus.