PLE-3580

A 57-year-old man with multiple myeloma comes to the physician because of a 12-hour history of fever, sharp chest pain with deep inspiration, and cough productive of blood-tinged sputum. His temperature is 38.3 C (101 F), blood pressure is 120/78 mm Hg, pulse is 112/min, and respirations are 28/min. Crackles are heard at the right lung base. His hemoglobin level is 9.2 g/dL, leukocyte count is 2600/mm3, and platelet count is 6,000/mm3. Which organisms should empiric antibiotics be directed against?