While primarily genital, chancres may develop on the eyelid and conjunctiva. Other ocular signs in the primary stage include conjunctivitis, blepharitis, and alopecia. In the secondary stage of acquired syphilis, the patient will develop malaise, lymphadenopathy, fever, maculopapular skin lesions on the palms and soles, joint pain, headache, and loss of appetite. Ocular signs are most common in secondary syphilis and include episcleritis, anterior uveitis, uveitic glaucoma, neuroretinitis, chorioretinitis, ischemic retinal vasculopathy, and infectious optic neuropathy. Syphilis is caused by the spirochete bacteria, Treponema pallidum.
Transmission can also occur through blood transfusion.
After infection, a period of incubation ensues. The organism enters the lymphatic system and bloodstream and disseminates soon after contact. Shortly after infection, a chancre forms at the site of inoculation. The chancres spontaneously heal after two to eight weeks, and the patient enters the secondary stage of syphilis. In individuals with an intact immune system, the disease enters a period of latency.