A female patient with a new genital lesion presents to your sexually transmitted disease clinic. She is homeless, has no health insurance, and is an intravenous drug user. You suspect syphilis. Which of these techniques would be most appropriate to emonstrate treponemes?

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Quizplus · Accepted Answer

First, notice that the question specifically asks about demonstrating the presence of treponemes and not making the diagnosis of syphilis. (Also, note that the lesions are still present, which suggests that it is too early for serological methods to be reliable.) Then, remember that Treponema pallidum is still only cultured by research labs. Because treponemes are so thin in cross-section, they do not reliably show up on a Gram stain; thus, dark-field or FA (not mentioned as a choice) staining would be necessary.

A Female Patient with a New Genital Lesion Presents to Your