A man has a painless genital ulcer with a clean base. Which organism is the cause?
Answer and explanation
Correct answer: A. Treponema pallidum
- Step 1: A painless chancre is primary syphilis. Answer: Treponema pallidum. Why not the others: Chancroid is painful, herpes causes painful vesicles and LGV causes painful nodes.
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More Microbiology and Immunology questions
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