Drug of choice in methicillin-resistant Staphylococcus aureus –
**Core Concept**
The underlying principle being tested is the management of infections caused by **methicillin-resistant Staphylococcus aureus (MRSA)**, a type of bacteria resistant to many antibiotics. This requires knowledge of **antibiotic resistance patterns** and appropriate **antimicrobial therapy**.
**Why the Correct Answer is Right**
The correct answer is based on the most effective treatment option for MRSA infections. **Vancomycin** is a glycopeptide antibiotic that is effective against MRSA and is often considered the drug of choice. It works by inhibiting cell wall synthesis in bacteria.
**Why Each Wrong Option is Incorrect**
**Option A:** Incorrect because it is not specified, but typically, other options like penicillin or ampicillin are ineffective against MRSA due to resistance.
**Option B:** Incorrect for similar reasons, as many MRSA strains are resistant to multiple antibiotics.
**Option D:** Also incorrect, as while it may have some effect, it is not the preferred choice for MRSA treatment.
**Clinical Pearl / High-Yield Fact**
A key point to remember is that **vancomycin** is the drug of choice for MRSA infections, especially in severe cases.
**Correct Answer:** D. Vancomycin