Preview
A 45-year-old man is brought to the emergency department due to confusion and altered mental status. His friend, who brought him in, states the patient has been complaining of fevers accompanied by malaise for the past 2 weeks. The patient is currently living in a homeless shelter, but oftentimes he is seen sleeping on the streets by his friends. Medical history is unknown, but a month ago the patient was hospitalized for Pneumocystis jirovecii (formerly P. carinii) pneumonia. Temperature is 38.5°C (101.3°F), pulse is 80/min, and blood pressure is 135/85 mmHg. On physical examination, the patient is lethargic and mildly confused. Neck is supple, and there are no focal signs. The patient’s arms show multiple needle marks. The pathogen most likely responsible for this patient’s condition is most likely to show which of the following on further testing?