Drug not affecting pseudomonas aeruginosa –
**Core Concept**
Pseudomonas aeruginosa is a Gram-negative bacterium that can cause a range of infections, particularly in immunocompromised individuals. It is known for its resistance to many antibiotics, making treatment challenging. The question is asking about a drug that does not affect Pseudomonas aeruginosa.
**Why the Correct Answer is Right**
Pseudomonas aeruginosa is resistant to many antibiotics, including beta-lactams such as penicillins and cephalosporins. This is due to the production of beta-lactamases, enzymes that break down these antibiotics. One class of drugs that is not affected by beta-lactamases is the fluoroquinolones, which target the bacterial DNA gyrase and topoisomerase IV. However, the correct answer is a different class of antibiotics.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because [insert reason].
**Option B:** This option is incorrect because [insert reason].
**Option C:** This option is incorrect because [insert reason].
**Option D:** This option is incorrect because [insert reason].
**Clinical Pearl / High-Yield Fact**
Pseudomonas aeruginosa is often resistant to multiple antibiotics, making treatment challenging. It is also known to cause a range of infections, including pneumonia, urinary tract infections, and skin infections. The production of beta-lactamases is a key factor in its resistance to many antibiotics.
**Correct Answer:** D. Colistin.