Chloroquine is useful in:
**Core Concept**
Chloroquine is an antimalarial drug that works by inhibiting the growth and replication of Plasmodium parasites in the erythrocytic stage of malaria. It is also used in the treatment of autoimmune diseases like rheumatoid arthritis and lupus due to its immunomodulatory effects.
**Why the Correct Answer is Right**
Chloroquine accumulates in the acidic food vacuoles of Plasmodium parasites, interfering with the parasite's ability to digest hemoglobin. This leads to the accumulation of toxic heme, which ultimately causes the death of the parasite. Additionally, chloroquine has anti-inflammatory properties, which contribute to its effectiveness in treating autoimmune diseases.
**Why Each Wrong Option is Incorrect**
**Option A:** Chloroquine is not primarily used for treating bacterial infections, as it lacks significant antibacterial activity.
**Option B:** Chloroquine is not typically used for treating viral infections, as it has limited antiviral effects.
**Option C:** Chloroquine is not a first-line treatment for fungal infections, as it is not effective against fungal pathogens.
**Clinical Pearl / High-Yield Fact**
Chloroquine can cause retinal toxicity, especially in patients with pre-existing retinal disease or those taking high doses for extended periods. Regular eye exams are essential for patients on long-term chloroquine therapy.
**Correct Answer:** D. Autoimmune diseases like rheumatoid arthritis and lupus