Syphilis

Key Features

Essentials of Diagnosis

• The spirochete can infect almost any organ or tissue in the body and cause protean clinical manifestations

• Transmission occurs most frequently during sexual contact

General Considerations

• Caused by Treponema pallidum, a spirochete capable of infecting almost any organ or tissue in the body and of causing protean clinical manifestations (Table 34–1)

• The risk of syphilis after unprotected sex with an individual with infectious syphilis is ~30–50%

• Congenital syphilis: transplacental transmission occurs in infants of untreated or inadequately treated mothers

• Two major clinical stages

  • Early (infectious) syphilis

  • Late syphilis

• Stages are separated by a symptom-free latent period

• During early latency (within the first year after infection) the infectious stage may recur

• Early (infectious) syphilis

  • Primary lesions (chancre and regional lymphadenopathy)

  • Secondary lesions (commonly involving skin and mucous membranes, occasionally bone, CNS, or liver)

  • Congenital lesions

• Late syphilis consists of

  • So-called benign (gummatous) lesions involving skin, bones, and viscera

  • Cardiovascular disease (principally aortitis)

  • CNS and ocular syndromes

Demographics

• In 2018, the number of primary and secondary syphilis cases in the United States was 35,063 and the rate of 10.8 per 100,000 people, which represents an increase of 14% over 2017

• Most cases of syphilis in the United States continue to occur in men who have sex with men (MSM)

• However, despite the increase in primary and secondary syphilis in MSM, a concomitant increase in the incidence of HIV has not been observed

Clinical Findings

Symptoms and Signs

Primary

• Painless ulcer (chancre) on genitalia, perianal area, rectum, pharynx, tongue, lip, or elsewhere 2–6 weeks after exposure

• Nontender enlargement of regional lymph nodes

Secondary

• Generalized maculopapular rash

• Mucous membrane lesions, which can be found on the lips, ...