Alternative names

Syphilis is a sexually transmitted or congenital infection caused by the bacterium Treponema pallidum. See also congenital syphilis, secondary syphilis, and Tertiary syphilis.

Causes, incidence, and risk factors

Syphilis is an infectious disease caused by the spirochete Treponema pallidum, which penetrates broken skin or mucous membranes. Transmission occurs most frequently by sexual contact. Congenital syphilis can be transmitted to the fetus during any stage in pregnancy. Syphilis is widespread in the United States and primarily involves sexually active adults between 20-29 years of age.

Syphilis has several stages. In the primary stage, painless sores, called chancres, appear approximately 2-3 weeks after initial exposure. Some individuals with primary syphilis may not notice chancres nor have symptoms associated with them, in particular if the chancres are located in the rectum or cervix. In about 4 to 6 weeks chancres will usually disappear.

Approximately one-third of untreated individuals will progress to the second stage: secondary syphilis. This usually occurs at about 2 to 8 weeks after the appearance of the original chancre in some cases the chancre may still be present. Secondary syphilis is the stage where the bacteria have spread in the bloodstream and have reached their highest numbers.

The most common symptoms include skin rash which can be varied in appearance, yet frequently involves the palms and soles, in addition to lesions in the mouth, vagina, penis (mucous patches), swollen lymph nodes, and fever. This stage is the most contagious stage of syphilis. It usually resolves within weeks to a year. A latent phase follows, which may last for years and is characterized by the absence of symptoms.

The final stage of syphilis is called tertiary syphilis and is characterized by brain or central nervous system involvement (neurosyphilis), cardiovascular involvement with inflammation of the aorta (aortitis or aneurysms), and gummatous syphilis (destructive lesions of the skin and bones).


The symptoms of syphilis depend on the stage of the disease. In addition, a significant proportion of individuals may remain without symptoms.

Syphilis; primary:

  • chancres - (usually single yet may be multiple) painless sores on genitals, rectum, or mouth  
  • enlarged lymph nodes in the area adjacent to the chancre

Syphilis; secondary:

  • skin rash - usually throughout the body with both flat and raised patches which may involve the palms and soles of the feet.  
  • extensive lymph node enlargement  
  • mucous patches (painless silvery ulcerations of mucous membranes - seen mostly in the mouth and on the genitals)  
  • condyloma lata: coalescing papules which form a grey-white plaque frequently in folds such as groin, genital areas, axilla, and under the breasts  
  • hair loss (alopecia)  
  • general symptoms such as fever, fatigue, loss of appetite, and aches and pains in bones

Syphilis; tertiary.

  • infiltrative, destructive lesions of skin, bones, or liver (gummatous syphilis)  
  • cardiovascular syphilis, which leads to inflammation of the aorta (aortitis) and can be associated with aortic aneurysms  
  • central nervous system disorders with involvement of the meninges, brain, spinal cord, eye, or auditory system.

Signs and tests

The proper diagnostic tests for syphilis depend on the stage of the disease and may include: dark field examination of primary lesion (in primary syphilis), and blood tests such as VDRL or RPR and FTA-ABS. In the case of neurosyphilis, a spinal tap is required to make the diagnosis and may be sent for VDRL and/or FTA-ABS.


The mainstay of therapy for syphilis is proper antibiotic treatment. The antibiotic of choice is penicillin, yet doxycycline may be used as an alternative in individuals with a penicillin allergy.

Penicillin is given either intramuscularly or intravenously depending on the stage of syphilis. After appropriate antibiotic treatment is given for syphilis, follow up blood tests (RPR) are usually performed to assess the adequacy of treatment.

Syphilis is a reportable infection - that is, it must be reported to public health authorities for assistance in identifying and treating potentially infected sexual partners.

Expectations (prognosis)
Prompt treatment and monitoring for response to treatment for syphilis can cure the disease. Once late complications develop (tertiary syphilis), long-term health problems are likely despite therapy.


The complications of syphilis are related to the development of the syndromes associated with tertiary syphilis:

  • neurosyphilis  
  • cardiovascular complications (aortitis and aneurysms)  
  • destructive lesions of the skin and bones (gummas).

In addition, untreated secondary syphilis during pregnancy may result in transmission to the fetus (congenital syphilis).

Calling your health care provider
Notify your health care provider if you develop signs or symptoms of syphilis - while there are several conditions which may have similar symptoms, you will need to undergo a careful medical evaluation.


Safer sexual practices and consistent condom use are important measures in the prevention of syphilis. In addition, early diagnosis and treatment is needed to prevent ongoing transmission of this disease, as is screening during any evaluation for a sexually transmitted disease.

Screening of all pregnant women for syphilis is another measure to decrease the risk that the disease will be passed on to the fetus.

Johns Hopkins patient information

Last revised: December 3, 2012
by Martin A. Harms, M.D.

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