Review Question - QID 213409

A 56-year-old woman is brought in by ambulance to the emergency department after being found unconscious in her home. Emergency medical services said she called her workplace 4 days ago saying she was sick. She had a fever and was “coughing up phlegm.” When she never returned to work, her employer called the police. The patient has had multiple emergency room visits for pancreatitis. She has depression and human immunodeficiency virus. Her medications include mirtazapine, raltegravir, tenofovir, and emtricitabine. She was incarcerated last year for 6 months. She now works as a waitress on a cruise ship and got back from a trip 1 week ago. The patient’s temperature is 102°F (38.9°C), blood pressure is 102/60 mmHg, pulse is 110/min, and respirations are 28/min with an oxygen saturation of 94% on room air. On physical exam, she is lethargic and her speech slurred. Her breath smells of alcohol, she has vomit on her shirt, and she is coughing up foul-smelling sputum. There are rhonchi and rales at the base of the right lung. Labs are drawn as shown below:

Leukocyte count: 16,000/mm^3 with normal differential
Hemoglobin: 10.2 g/dL
Mean corpuscular volume (MCV): 106 um^3
Platelet count: 300,000/mm^3
CD4 count: 676/mm^3

The patient’s peripheral smear is shown in Figure A. A chest radiograph shows a right lower lobe consolidation. A Gram stain of expectorated sputum reveals both gram-positive and gram-negative organisms. A sputum culture and blood culture are pending. Which of the following is the most likely cause of this patient’s current symptoms?