Pseudomonas aeruginosa

Which virulence factor of Pseudomonas aeruginosa is a heat-labile exotoxin that catalyzes ADP-ribosylation of elongation factor-2 (EF-2), leading to inhibition of protein synthesis?

Which of the following is the primary mechanism of antibiotic resistance in Pseudomonas aeruginosa that confers resistance to β-lactam antibiotics?

A 72-year-old woman with diabetes mellitus type 2 and chronic kidney disease (eGFR 28 mL/min) is admitted with a 10-day history of painful, necrotic lesion on her left foot following a puncture wound from a contaminated nail. On examination, the wound shows black eschar with surrounding erythema and edema. Tissue culture grows a gram-negative rod that is oxidase-positive and produces blue-green pigment. Histology shows extensive tissue necrosis with minimal inflammatory response. What is the primary virulence factor responsible for the tissue destruction in this infection?

A 62-year-old male with COPD presents with acute exacerbation characterized by purulent greenish sputum, fever, and worsening dyspnea. Chest X-ray shows bilateral lower lobe infiltrates. Gram stain of sputum reveals gram-negative rods. Which investigation is most appropriate to confirm the suspected diagnosis of Pseudomonas aeruginosa respiratory infection?

A 58-year-old male with COPD and recent hospitalization presents with fever (38.9°C), productive cough with greenish sputum, and dyspnea for 3 days. Chest X-ray shows bilateral lower lobe infiltrates. Sputum culture grows a gram-negative rod that is oxidase-positive, produces a fruity odor, and grows on cetrimide agar. Blood cultures remain negative. Which of the following is the most appropriate initial empirical antibiotic regimen for this patient?