The primary phase of acquired syphilis is characterized by:

• A. A raised, painless chancre
• B. A widespread rash including palms and soles
• C. Latent infection with no signs
• D. Neurological symptoms early

Answer: (A)

In the primary stage of syphilis, the hallmark is a painless chancre at the site where the bacteria entered. This lesion typically appears about three weeks after exposure, can be singular or multiple, and is usually firm and indurated with a clean base. It’s not painful, which helps distinguish it from other ulcers, and it often goes unnoticed or is mistaken for another type of sore. The chancre is highly infectious during this stage but heals on its own within a few weeks, even without treatment.

The other features listed appear later in the disease course: a widespread rash including the palms and soles is classic for secondary syphilis; a latent infection has no signs or symptoms; and neurological symptoms, if they occur early, reflect neurosyphilis rather than the primary phase. Therefore, the primary phase is best defined by the presence of a painless chancre.