Primary syphilis presents with which hallmark feature?

• A. Painful genital ulcer
• B. Painless genital ulcer
• C. Genital warts
• D. Genital ulcers with excruciating pain

Answer: (B)

Primary syphilis is defined by a chancre at the site of inoculation. The hallmark is a painless, indurated ulcer with a clean base, often accompanied by regional lymphadenopathy. Pain is not a feature, which helps distinguish it from other sexually transmitted ulcers that are painful (such as chancroid or herpes) or from non-ulcerative lesions like genital warts caused by HPV. The lesion is highly infectious in this early stage and typically appears about a few weeks after exposure. So the best answer is a painless genital ulcer because that painless chancre is the classic presenting feature.