Which antibiotic is a carbapenem commonly used for broad-spectrum coverage including Pseudomonas in hospital-acquired pneumonia?

• A. Ertapenem
• B. Ceftriaxone
• C. Aztreonam
• D. Meropenem

Answer: (D)

The key idea is needing an antibiotic with very broad coverage that includes Pseudomonas for hospital-acquired pneumonia. Carbapenems fit that profile, and among them meropenem offers reliable activity against Pseudomonas as well as a wide range of Gram-positive cocci and anaerobes, which is important because HAP often involves mixed flora. Meropenem also tends to have favorable pharmacology for lung infections, with good tissue penetration and a lower risk of seizures than some alternatives like imipenem.

Ertapenem, while broad, does not cover Pseudomonas, so it’s not suitable when Pseudomonas is a concern. Aztreonam covers many Gram-negatives including Pseudomonas but lacks Gram-positive and anaerobic coverage, so it’s not as broad as needed for typical HAP pathogens. Ceftriaxone does not have Pseudomonas activity, making it insufficient for this scenario.

Thus, meropenem is the best choice for broad-spectrum coverage including Pseudomonas in hospital-acquired pneumonia.