Antibody elevated in parasitic infection ?
**Core Concept**
The question is testing the student's knowledge of the immune response to parasitic infections. The correct answer is related to a specific type of antibody that is elevated in response to certain parasites.
**Why the Correct Answer is Right**
Elevated IgE levels are commonly seen in parasitic infections, particularly those caused by helminths such as roundworms, hookworms, and tapeworms. IgE plays a key role in the allergic response and is involved in the activation of mast cells, which release histamine and other mediators that contribute to the pathogenesis of parasitic infections. The high IgE levels in parasitic infections are due to the production of eosinophilic granules, which contain the major basic protein and eosinophil cationic protein.
**Why Each Wrong Option is Incorrect**
* **Option A:** Elevated IgM levels are typically seen in bacterial infections, not parasitic infections. IgM is the first antibody to be produced in response to an infection and is often seen in acute bacterial infections such as meningitis.
* **Option B:** Elevated IgG levels are commonly seen in viral infections, not parasitic infections. IgG is the most common antibody isotype and is involved in the long-term defense against infections.
* **Option C:** Elevated IgA levels are typically seen in infections that involve the mucosal surfaces, such as respiratory or gastrointestinal infections. While IgA can be elevated in some parasitic infections, it is not the most characteristic antibody response.
**Clinical Pearl / High-Yield Fact**
In parasitic infections, elevated IgE levels are often associated with eosinophilia, which is a significant increase in the number of eosinophils in the blood. This is because eosinophils are involved in the immune response to parasites and are often recruited to the site of infection.
**Correct Answer:** C.