A firm, painless vaginal ulcer is seen with which disease?

• A. Gonorrhea
• B. Syphilis
• C. Chancroid
• D. Herpes

Answer: (B)

A firm, painless vaginal ulcer is classic for a chancre from primary syphilis. The ulcer tends to be indurated with a clean base and is typically painless, reflecting the localized infection by Treponema pallidum without a harsh inflammatory response. This helps distinguish it from chancroid, which presents as a soft, painful ulcer with ragged edges and tender lymph nodes, and from herpes, which causes painful, shallow ulcers that arise from vesicular lesions. Gonorrhea does not usually cause a genital ulcer. Diagnosis is confirmed with serologic tests (non-treponemal screening with a treponemal test) or direct visualization of spirochetes, and treatment is with penicillin.