Syphilis is a chronic infection caused by the bacterium Treponema pallidum. The manifestations of disease are notoriously protean, occurring in any one individual in different stages over time .
The epidemiology, pathogenesis, clinical manifestations, diagnosis, and therapy of early syphilis will be reviewed here. Late syphilis and the pathophysiology, natural history, and serologic diagnosis of syphilis are discussed separately. Syphilis in the HIV-infected patient is discussed elsewhere. (See "Pathogenesis, clinical manifestations, and treatment of late syphilis" and "Pathophysiology, transmission, and natural history of syphilis" and "Diagnostic testing for syphilis" and "Epidemiology, clinical presentation, and diagnosis of syphilis in the HIV-infected patient".)
Early syphilis — Early syphilis is defined as the stages of syphilis (primary, secondary, and early latent syphilis) that typically occur within the first year after acquisition of the infection.
Latent syphilis — Latent syphilis is characterized by asymptomatic infection with a normal physical examination in association with a positive serology. Latent syphilis is categorized as "early" or "late" depending on the established date of infection. Early latent syphilis infers infection within one year. All other cases are referred to as late latent syphilis or latent syphilis of unknown duration .
The importance of correct classification is related to the risk of transmission and duration of treatment: