Maternal Antibody responsible for heartblock in a baby born to mother suffering from SLE
**Core Concept**
The question is testing the knowledge of maternal autoantibodies and their potential effects on the fetus, specifically in the context of Systemic Lupus Erythematosus (SLE). The underlying principle involves the transfer of antibodies from the mother to the fetus through the placenta, which can lead to various complications, including congenital heart block.
**Why the Correct Answer is Right**
In SLE, the mother's immune system produces autoantibodies, including anti-Ro (SS-A) and anti-La (SS-B) antibodies. These antibodies can cross the placenta and bind to the fetal heart, leading to an immune-mediated destruction of the fetal heart tissue. This can result in congenital heart block, which is characterized by a conduction defect in the fetal heart, leading to a decrease in the heart rate. The anti-Ro and anti-La antibodies are responsible for this phenomenon, making them the maternal antibodies responsible for heart block in the baby.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because it does not specify the correct maternal antibodies responsible for heart block in the baby. While other autoantibodies may be present in SLE, anti-Ro and anti-La are the specific antibodies implicated in congenital heart block.
* **Option B:** This option is incorrect because it is not related to the specific context of SLE and congenital heart block. Other maternal antibodies may be present in pregnancy, but they are not the primary cause of heart block in this scenario.
* **Option C:** This option is incorrect because it is a different type of antibody that is not specifically implicated in congenital heart block. The correct antibodies are anti-Ro and anti-La, not anti-SSB.
**Clinical Pearl / High-Yield Fact**
It's essential to remember that the presence of anti-Ro and anti-La antibodies in the mother is a significant risk factor for congenital heart block in the baby. This can occur even if the mother is asymptomatic or has mild SLE symptoms. Close monitoring and early intervention are crucial in such cases to prevent long-term cardiac complications.
**Correct Answer:** C. Anti-Ro (SS-A) antibodies