Which agent is a beta-lactam with anti-pseudomonal activity commonly used in HAP/VAP?

• A. Piperacillin-tazobactam
• B. Vancomycin
• C. Linezolid
• D. Doxycycline

Answer: (A)

The key idea is choosing an antibiotic with both beta-lactam activity and reliable antipseudomonal coverage for hospital-acquired or ventilator-associated pneumonia. Piperacillin-tazobactam fits this well: it’s a broad-spectrum beta-lactam (an extended-spectrum penicillin) paired with a beta-lactamase inhibitor, tazobactam, which boosts its activity against bacteria that produce beta-lactamases. This combination provides strong activity against Pseudomonas aeruginosa, a common and serious pathogen in HAP/VAP, making it a go-to empirical choice when Pseudomonas is a concern.

The other options don’t fit this need as well. Vancomycin and linezolid target Gram-positive organisms (including MRSA) but do not provide reliable antipseudomonal activity. Doxycycline is not a beta-lactam and has limited, inconsistent activity against Pseudomonas, so it isn’t suitable for empiric anti-pseudomonal coverage in these pneumonia settings.