A 65-year-old man with a history of chronic obstructive pulmonary disease is hospitalized following elective abdominal surgery. On postoperative day 8, he develops fever (38.9°C), productive cough with purulent sputum, and progressive hypoxia. Physical examination reveals scattered crackles in the right lower lobe. Vital signs: BP 128/76 mmHg, HR 102 bpm, RR 22/min, SpO2 88% on room air. Laboratory studies show WBC 14,200/μL. Chest X-ray demonstrates a new right lower lobe infiltrate. Sputum culture grows gram-negative rods that are oxidase-positive and resistant to multiple beta-lactam antibiotics, including ceftazidime. Which of the following organisms is most likely responsible for this patient's pneumonia?
- A)Chlamydia pneumoniae
- B)Streptococcus pneumoniae
- C)Haemophilus influenzae
- D)Klebsiella pneumoniae
- E)Pseudomonas aeruginosaGABARITO
Explicação
Pseudomonas aeruginosa is the most likely pathogen. Key clinical features supporting this diagnosis: (1) nosocomial acquisition—pneumonia develops 8 days post-operatively in a hospitalized patient, classic for healthcare-associated pneumonia; (2) gram-negative... Ver explicação completa e trilha adaptativa →