Syphilis is a sexually transmitted infection caused by the bacterium Treponema pallidum. It progresses through several stages, each with characteristic symptoms. One of the hallmark symptoms of syphilis are sores known as chancres that develop at the site of infection. The size of syphilis chancres can vary depending on the stage of the infection.
Size of Syphilis Chancres by Disease Stage
Primary Syphilis
In the initial stage of syphilis infection known as primary syphilis, chancres usually develop around 3 weeks after exposure (range 9-90 days). Primary syphilis chancres tend to be:
– 0.3-3 cm in diameter
– Round, oval, or irregularly shaped
– Firm, painless, and non-itchy
– Commonly appear on the genitals, around the anus, or in the mouth
Primary syphilis chancres start as small, painless bumps that gradually enlarge and ulcerate to form open sores. There is usually just one sore, but multiple chancres can develop. Without treatment, primary syphilis chancres will heal on their own in 3-6 weeks. However, the infection remains and progresses to the secondary stage.
Secondary Syphilis
In secondary syphilis, new chancres may periodically appear as systemic symptoms flare up. Secondary syphilis chancres tend to be:
– Smaller than primary chancres
– 0.5-1.0 cm in diameter
– Located in areas like the mouth, genitals, buttocks, fingers, or anus
The chancre sores of secondary syphilis are often subtle and may go unnoticed. They heal more rapidly than primary chancres, usually within 2-6 weeks. The overall rash and symptoms of secondary syphilis will continue without treatment.
Tertiary Syphilis
The tertiary stage of syphilis develops around 3-15 years after initial infection in a third of untreated individuals. This stage is characterized more by the damage syphilis causes throughout the body than by chancres themselves. However, in some cases, chronic, slowly-healing chancres known as gummas can develop:
– Gummas range from 0.5-2.0 cm
– Most commonly affect bones, skin, and mucous membranes
– Can cause extensive tissue destruction if left untreated
Appearance of Syphilis Chancres
In addition to size, syphilis chancres have some common characteristics in appearance:
Single or Multiple
Primary syphilis typically only causes one chancre at the infection site. However, multiple chancres can develop, especially if there are multiple exposure points. Secondary syphilis may cause occasional, recurrent chancres as the infection persists.
Firm and Painless
Syphilis chancres tend to be firm and painless to the touch, unlike painful blisters from infections like herpes. The base feels rubbery and is not easily moved.
Clean Ulcer Base
When a syphilis chancre ulcerates, the base tends to be clean and pinkish-red. There is no pus or exudate.
Raised, Rolled Borders
The edges around syphilis chancres are often raised and well-demarcated from normal skin. The border may have a rolled, cartilaginous feel.
Regional Lymphadenopathy
Painless swelling of the lymph nodes in the region around a syphilis chancre often develops as the body mounts an immune response. This is a helpful diagnostic sign.
Where Do Syphilis Chancres Appear?
Syphilis chancres often occur at or near the initial site of infection. Common locations include:
Genitals
On males, syphilis chancres frequently occur on the penis, especially the glans, coronal sulcus, or shaft. On females, they often develop on the labia, vaginal entrance, cervix, or perineum.
Anus or Rectum
Receptive anal sex can transmit syphilis, leading to chancres around the anus or just inside the rectum.
Mouth and Lips
Oral sex can transmit syphilis. Chancres may occur on the lips, tongue, soft palate, or tonsils.
Fingers
Direct contact with a chancre can spread syphilis to the fingers. Chancres may occur around or under fingernails.
Breasts and Nipples
Syphilis can be spread through skin-to-skin contact and cause chancres on the breasts or nipples in some cases.
Eyes
Rarely, syphilis can be transmitted by contact with eyes and cause chancres on the eyelids or conjunctiva.
Differences by HIV Status
Those with HIV and syphilis co-infection may experience larger, more ulcerated, and prolonged-healing syphilis chancres.
Larger Size
Syphilis chancres in HIV+ individuals tend to be larger, sometimes up to 2-3 cm in diameter.
Deeper and More Ulcerated
The chancres in those with HIV are often deeper and more ulcerated than in HIV- individuals.
Longer Lasting
Syphilis chancres can persist longer in HIV+ individuals, sometimes for 2-6 months compared to 3-6 weeks in HIV- counterparts.
Diagnosing Syphilis from Chancres
Healthcare providers can use the appearance and characteristics of syphilis chancres to aid diagnosis. However, syphilis testing is needed to confirm.
Darkfield Microscopy
Scraping chancre fluid and examining under a special microscope can sometimes reveal spirochetes. This method can be used for early diagnosis.
Serological Testing
Blood tests check for antibodies to syphilis. Most reliable tests include:
– Nontreponemal tests (VDRL, RPR)
– Treponemal tests (TP-PA, FTA-ABS, EIA, CIA)
Direct Fluorescent Antibody Testing
A skin biopsy of a chancre can allow direct detection of T. pallidum by fluorescent antibody staining.
PCR
Polymerase chain reaction can detect T. pallidum DNA from chancre swabs or fluid samples.
Treatment
Parenteral penicillin G is the preferred treatment for all stages of syphilis. Doxycycline, tetracycline, or ceftriaxone may be used for penicillin-allergic patients.
Primary, Secondary, and Early Latent Syphilis
Treatment at these stages usually consists of:
– Benzathine penicillin G 2.4 million units IM x 1 dose
Late Latent and Tertiary Syphilis
More extensive treatment is required at later stages:
– Benzathine penicillin G 2.4 million units IM once weekly x 3 weeks
For neurosyphilis, IV aqueous crystalline penicillin G 18-24 million units per day is recommended.
Follow-up quantitative nontreponemal serological testing at 6 and 12 months after treatment is important to confirm response and cure.
Prognosis with Treatment
With prompt diagnosis and antibiotic treatment, syphilis chancres will completely heal without complications. Scarring does not occur. Serological titers decline following successful treatment.
Progression Without Treatment
If syphilis goes untreated, the initial chancre will heal spontaneously, but the infection will progress through stages:
Primary Syphilis
The initial chancre heals in 3-6 weeks even without treatment. The disease progresses to secondary syphilis.
Secondary Syphilis
New mucocutaneous lesions and systemic symptoms develop 6 weeks to 6 months after the original chancre. The rash can be extensive.
Latent Syphilis
After secondary syphilis, the infection enters an asymptomatic latent phase that can last for years before potential tertiary complications.
Tertiary Syphilis
After 3-15 years, up to a third of untreated patients may develop severe complications like neurosyphilis, cardiovascular syphilis, or gummatous syphilis.
Prevention
Syphilis transmission can be prevented by:
– Using condoms correctly during oral, vaginal, and anal sex
– Having sex only with mutually monogamous, uninfected partners
– Regular syphilis testing for those with new partners or multiple partners
– Prompt treatment if exposed to prevent progression
Public health strategies like improved access to testing and treatment, partner tracing, and education are key for syphilis control and prevention. A vaccine is not yet available.
Conclusion
Syphilis chancres are painless ulcers that develop in primary, secondary, and tertiary syphilis. Lesion size can range from 0.3-3 cm, with HIV co-infection associated with larger chancres. While the appearance of chancres can help diagnose syphilis, confirmatory testing is essential. All stages of syphilis require antibiotic treatment, typically with penicillin, to prevent progression to severe late complications. Prompt diagnosis and treatment results in excellent outcomes and chancre healing without scarring.