Primary Syphilis

Incubation period

21 days (9-90 days).

Symptoms and Signs

• Characterised by an ulcer known as “the chancre”, in genital and nongenital sites, with localised lymphadenopathy.
• The chancre is often painless with a clean base and indurated edges, BUT can be multiple and painful
• Depending on the site, chancres may go unnoticed and heal spontaneously
• Any anogenital ulcer should be considered to be syphilis until proven otherwise

Dark ground microscopy, PCR testing and serology can help in the diagnosis of primary syphilis.

• Where possible/ available perform dark ground microscopy of the serous exudate from any visible ulcers - slide taken to lab immediately. (Know if your laboratory can do dark ground microscopy) (NB: Dark ground microscopy is of no value in intra-anal or oral lesions. Only take a dark ground if you know how, get help if you don’t).
• If dark ground microscopy is not available then consider sending the patient to the appropriate centre.
• If a suspicious lesion is dark ground negative, consider bringing the patient back for up to two more dark grounds and repeat serology one week later.

• PCR testing is available via the Regional Virus laboratories in Glasgow and Edinburgh: place the swab in viral transport medium and send to your microbiology department who will forward to the relevant virus lab. PCR is the preferred method for oral and other lesions where contamination with other commensal treponemes is likely. PCR is not a replacement for dark ground microscopy due to the time taken to get the result but should be done alongside dark ground microscopy if it is available. Please note all PCR ulcer swabs should be tested for HSV1/2 and T.pallidum

• Serological tests in primary syphilis may be negative at this stage (usually become positive 2 weeks after the chancre appears).
• If initial serology is inconclusive and there is a clinical suspicion, arrange repeat serology a week later and ideally at 6 weeks and 3 months
• Avoid the use of antibiotics if possible at this stage if the diagnosis remains uncertain and the patient reports no exposure to syphilis. Treatment at this stage may prevent a serological response. Likewise if the patient is requiring antibiotics for another reason then this may affect syphilis serology

Treatment must be initiated as soon as a diagnosis is reasonably established to limit infectivity and reduce risk of progression to secondary syphilis. Do not defer therapy because someone is uncertain about HIV testing or to bring patients back for further confirmatory tests. If you are happy with the clinical picture and the dark ground/ PCR is positive then start treatment immediately.

*Benzathine penicillin G 2.4 MU intramuscular
(as Extencilline 8ml) (NB unlicensed medication, named patient form may be needed)
For administration, see Preparation Instructions for Extencilline 2.4MU
PENICILLIN ALLERGY: Doxycycline 100mg twice daily orally for 14 day

Jarisch Herxheimer reaction may occur at approximately 8 hours. This is an acute febrile illness with headache, myalgia, rigours which resolves in 24 hours and is common in early infection (advise rest, paracetamol). Usually this is not clinically important unless there is neurological or ophthalmogical
involvement or if the patient is pregnant. In these situations prednisolone and further monitoring may be advised (discuss with consultant)

Anaphylaxis – facilities for resuscitation must be present. Refer to local policy for further guidance

Patients should remain on the premises for 15 minutes after receiving their 1st injection to allow observation for immediate adverse reactions.

Partner Notification

All patients diagnosed with syphilis need specialist input and to be seen by a sexual health adviser experienced in partner notification for Syphilis at diagnosis and at each follow up visit, until partner notification and any local surveillance is documented as complete.

Sexual partners within the last 3 months should be notified.

Follow-up

• Clients should refrain from sexual contact until any lesions are fully healed and 2 weeks following treatment completion
• Assess clinically at the end of treatment. Repeat serology at 3, 6 and 12 months after the end of treatment regime then if indicated, six monthly until VDRL/ RPR is negative or serofast.
• If VDRL/RPR was positive at presentation expect a four-fold drop (2 dilution steps) in titre by six to twelve months.
• If VDRL/RPR titre does not fall, or at any stage shows a >2-fold rise, discuss with senior doctor
• Discharge only at 12 months if VDRL/RPR negative or if VDRL/RPR is serofast and has appropriately decreased as above
• Ask permission to write to GP to confirm treatment complete, give patient a written summary of treatment with discharge serology