]> 2026-07-31T09:40:50+00:00 WBR0253 0 en Sulfisoxazole Trimethoprim Rifampin Penicillin Rifabutin Microbiology A 46-year-old homeless man presents to the emergency department (ED) with complaints of fever, dyspnea, and non-productive cough. He explains that his symptoms did not occur acutely, but have progressively worsened over the past few weeks. The patient does not smoke, but drinks 6-8 beers every day. He lives in a shelter for the homeless. His past medical history is significant for end-stage renal disease and kidney transplantation, for which he currently receives immunosuppressive therapy. In the ED, the patient's temperature is 39.7 °C (103.5 °F), blood pressure is 138/86 mmHg, and heart rate is 102/min. He appears very thin and severely malnourished. Physical examination is remarkable for coarse crackles on anterior auscultation of the right upper lung field. Chest x-ray demonstrates nodular infiltrates and cavitations in the right upper lobe. The patient is admitted and is started on broad-spectrum antimicrobial therapy. The next day, sputum culture shows an aerobic, gram-positive rod with a beaded acid-fast appearance on microscopy. Which antimicrobial agent is the optimal monotherapeutic option to treat this patient's condition? A Pulmonology Infectious Disease 2020-10-27T23:55:17Z 2459150.4967245 WBR0253