Bacterial Infections USMLE Step 1 Practice Question
A 23 year old woman presents with fever, migratory polyarthralgias, and several pustular lesions on the hands and feet. She is sexually active with inconsistent condom use. Pelvic examination reveals mucopurulent cervical discharge. Synovial fluid culture is negative. Which of the following is the most likely explanation for the negative joint culture despite disseminated infection?
Answer choices
- AThe organism causes disease through a preformed toxin only
- BThe organism is intracellular and difficult to grow on routine mediaCorrect answer
- CThe organism cannot survive outside anaerobic conditions
- DThe organism is a virus rather than a bacterium
- EThe organism lacks a peptidoglycan cell wall
- FThe organism produces a polysaccharide capsule that prevents culture on standard agar plates
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