What does the indirect Coombs test detect?

What does the indirect Coombs test detect?

• A. Anti-D antibodies in maternal serum to assess rh sensitization
• B. Direct fetal antigens in maternal blood
• C. Antibodies to TORCH pathogens
• D. Platelet antibodies in maternal serum

Answer: (A)

The indirect Coombs test screens maternal serum for antibodies that could attack fetal red blood cells, most commonly anti-D in Rh-negative pregnancies. By incubating the mother’s serum with Rh-positive donor red cells and then adding antiglobulin, any circulating alloantibodies cause agglutination. The presence and level of these antibodies help assess the risk of hemolytic disease in the fetus and guide management, such as Rh immune globulin prophylaxis or closer fetal monitoring if sensitization is present. The other options don’t fit because this test does not look for fetal antigens in maternal blood, nor is it used for TORCH infections, nor for detecting maternal antibodies against platelets.

The indirect Coombs test screens maternal serum for antibodies that could attack fetal red blood cells, most commonly anti-D in Rh-negative pregnancies. By incubating the mother’s serum with Rh-positive donor red cells and then adding antiglobulin, any circulating alloantibodies cause agglutination. The presence and level of these antibodies help assess the risk of hemolytic disease in the fetus and guide management, such as Rh immune globulin prophylaxis or closer fetal monitoring if sensitization is present.

The other options don’t fit because this test does not look for fetal antigens in maternal blood, nor is it used for TORCH infections, nor for detecting maternal antibodies against platelets.