Is the great imitator back? A case series on atypical presentation of primary syphilis as multiple herpetiform ulcers.

Syphilis is a systemic human infection which is caused by Treponema pallidum, a spirochete. It is an obligate human pathogen, which is renowned for its immune-evasiveness. It is one of the most common sexually transmitted infection that present as genital ulcer disease. The classic ulcerative lesion of syphilis is referred to as a painless hard chancre. This description can mislead inexperienced physicians when syphilis presents atypically. Traditionally, syphilis has been referred to as "the great imitator" owing to its myriad and multisystem involvement. We present a case series of eleven patients who presented with multiple, polysized or herpetiform ulcers over the genitalia and in whom the diagnosis of syphilis was eventually confirmed.