Bacterial Infections USMLE Step 1 Practice Question
A 43 year old man with chronic granulomatous disease presents with headache and focal left arm weakness. MRI of the brain shows a ring enhancing lesion. He also has a chronic cough, and chest imaging demonstrates nodular cavitary infiltrates. Sputum culture reveals branching filamentous organisms that are weakly acid fast and aerobic. Which of the following is the most likely causative organism?
Answer choices
- ANocardia asteroidesCorrect answer
- BMycobacterium kansasii
- CAspergillus fumigatus
- DToxoplasma gondii
- EActinomyces israelii
- FStreptomyces somaliensis
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