Patient was given chloroquine & doxycycline for 7 days. Patient&;s fever decreases in 4 days but , peripheral smear showed occasional gametocytes of plasmodium falciparum. This type of drug resistance is –
**Core Concept**
The question tests the understanding of **antimalarial drug resistance**, specifically the type of resistance exhibited by *Plasmodium falciparum* when treated with chloroquine and doxycycline. This scenario involves the **parasite's ability to survive** despite drug treatment.
**Why the Correct Answer is Right**
The correct answer is related to the **type of resistance** where the parasite is not completely cleared from the body, as evidenced by the presence of **gametocytes** in the peripheral smear after treatment. This indicates that while the drugs may have reduced the symptoms (such as fever), they did not fully eliminate the parasite, suggesting a form of **resistance**.
**Why Each Wrong Option is Incorrect**
**Option A:** This choice might refer to a different form of resistance or a different aspect of malaria treatment, not applicable in this context where gametocytes persist.
**Option B:** Similarly, this option might not accurately describe the scenario where clinical improvement is seen, but parasitic elements remain.
**Option C:** This could be related to a different mechanism or type of resistance, not fitting the description provided.
**Clinical Pearl / High-Yield Fact**
It's crucial to remember that the **presence of gametocytes** after treatment can indicate a specific type of drug resistance, and understanding the different types of resistance is key to managing malaria effectively. The ability of *Plasmodium falciparum* to develop resistance to antimalarial drugs is a significant concern in malaria treatment.
**Correct Answer:** D. Gametocytocidal resistance