Ocular syphilis and neurosyphilis in a patient with human immunodeficiency virus infection.

A patient who presented with severely decreased bilateral vision was found to have syphilis and neurosyphilis that responded well to a 14-day course of penicillin and prednisone. The patient tested positive for HIV, which can alter the natural course of syphilis, often making the diagnosis and treatment difficult. Conventional therapy for syphilis may not be effective in patients with HIV. Any patient with syphilis who is in a high-risk group should be tested for HIV; conversely, any patient with HIV should be tested for syphilis if signs or suspicions exist.