Not true about vancomycin is –
**Core Concept**
Vancomycin is a glycopeptide antibiotic that inhibits cell wall synthesis in Gram-positive bacteria by binding to the D-alanyl-D-alanine terminus of the cell wall precursor molecule, thus preventing peptidoglycan formation. It is commonly used to treat serious infections caused by methicillin-resistant Staphylococcus aureus (MRSA) and other resistant Gram-positive bacteria.
**Why the Correct Answer is Right**
Vancomycin acts by inhibiting the enzyme transpeptidase, which is responsible for cross-linking peptidoglycan chains in the bacterial cell wall. This results in weakened cell walls and ultimately leads to bacterial lysis and death. Vancomycin is effective against MRSA due to its ability to bind to the altered cell wall precursors produced by the bacteria.
**Why Each Wrong Option is Incorrect**
**Option A:** Vancomycin is a bacteriostatic agent. **Incorrect because** vancomycin is actually a bactericidal agent, meaning it directly kills bacteria rather than inhibiting their growth.
**Option B:** Vancomycin is used to treat infections caused by Pseudomonas aeruginosa. **Incorrect because** vancomycin is primarily used to treat infections caused by Gram-positive bacteria, including MRSA, and is not effective against Pseudomonas aeruginosa, which is a Gram-negative bacterium.
**Option C:** Vancomycin is primarily excreted by the kidneys. **Incorrect because** vancomycin is primarily excreted in the bile and feces, with a smaller amount being excreted by the kidneys.
**Clinical Pearl / High-Yield Fact**
It's essential to monitor patients receiving vancomycin for signs of nephrotoxicity, such as elevated serum creatinine levels, and to adjust the dose accordingly. Additionally, vancomycin is often administered in a two-stage infusion to minimize the risk of "red man syndrome," a condition characterized by flushing and rash.
**Correct Answer:** Not provided, please provide the options and the correct answer.