Donor X and recipient Y belong to same blood group. Transfusion has led to RBC agglutination because

Options

A. X is `Rh^(+)` , Y is `Rh^(-)`
B. X is `Rh^(-)` , Y is `Rh^(+)`
C. Both are `Rh^(+)`
D. Both are `Rh^(-)`

Answer

To solve the question regarding why RBC agglutination occurred during the transfusion between donor X and recipient Y, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Blood Groups**:
- Blood groups are determined by the presence or absence of specific antigens on the surface of red blood cells (RBCs). The major blood groups are A, B, AB, and O, which can also be classified as Rh positive or Rh negative based on the presence of the Rh factor.

2. **Identifying the Blood Group Compatibility**:
- In this scenario, both donor X and recipient Y belong to the same blood group. However, it is crucial to consider the Rh factor in addition to the ABO blood group.

3. **Role of the Rh Factor**:
- The Rh factor is a protein that can be present (Rh positive) or absent (Rh negative) on the surface of RBCs. If an Rh negative individual receives Rh positive blood, their immune system may recognize the Rh factor as foreign.

4. **Antibody Formation**:
- When Rh negative blood receives Rh positive blood, the recipient's immune system may produce antibodies against the Rh factor. This immune response can lead to a transfusion reaction.

5. **RBC Agglutination**:
- The antibodies produced by the recipient against the Rh factor will bind to the Rh positive RBCs from the donor. This binding causes agglutination, where the RBCs clump together, leading to complications.

6. **Conclusion**:
- Therefore, the transfusion led to RBC agglutination because the donor had Rh positive blood while the recipient had Rh negative blood, despite both belonging to the same ABO blood group.

### Final Answer:
Transfusion has led to RBC agglutination because donor X has Rh positive blood and recipient Y has Rh negative blood, resulting in an immune response against the Rh factor.