Eurofins Biomnis code

TREBM

Synonyms

• Syphilis

Clinic significance

Syphilis is a sexually transmitted infection caused by a bacterium: Treponema pallidum subps. pallidum. Its evolution is characterised by symptomatic stages (primary, secondary, tertiary and neurological syphilis) and asymptomatic stages (latent syphilis).
Primary syphilis takes the form of a syphilitic chancre on the ano-genital or bucco-pharyngeal mucosa, associated with peripheral adenopathy. Diagnosis is based on PCR testing of a lesion for the T. pallidum genome and on serology (which is negative at the onset of the chancre).
If left untreated, primary syphilis may progress to secondary or tertiary syphilis. Secondary syphilis is the bacterial phase of T. pallidum. It is characterised by mucocutaneous eruptions (roseola, palmoplantar syphilis, mucosal lesions) sometimes associated with other non-specific signs: alopecia, fever, arthralgia, polyadenopathy, ophthalmic lesions, osteitis, hepatitis. All organs may be affected. Tertiary syphilis (rare today) appears later, due to the granulomatous lesions that have formed around the spirochete. The main symptoms are cutaneous, mucosal, bony, cardiovascular, hepatic and neurological. Biological diagnosis of secondary and tertiary syphilis is also based on PCR testing of the T. pallidum genome on the lesions found, and on serology (titres may be very low in tertiary syphilis).
Neurosyphilis can occur at any stage of the disease, except in the case of primary syphilis. A CSF sample should be taken to test for the T. pallidum genome using PCR, and a non-treponemal test coupled with blood serology.
Latent syphilis is an asymptomatic phase diagnosed by positive serological tests.
In the case of infection in pregnant women, treponema may pass through the placenta. The risk of transmission is increased in the event of early infection. Serological screening should be carried out pre-conception or later if necessary. In case of suspected or confirmed infection, PCR can be performed on amniotic fluid, placenta, cord blood, nasal or oral secretions and mucocutaneous lesions. A non-treponemal test and an IgM test in newborns can also help in the diagnosis of congenital syphilis.

Prenalytics

• Mucocutaneous sampling, biopsy (except umbilical cord and placenta biopsy), CSF, cord blood, nasal secretions (infant)
• Refrigerated

Further information

• The use of the S14UK transport bag is Mandatory.
• Samples (other than swabs) must be sent as they are, in sterile bottles, without transport medium.
• Swab samples require the use of a transport medium (viral) supplied in kit K1.
• The following samples are not accepted: placenta, umbilical cord (except blood) or any other sample of foetal origin (except blood).

Specific equipment available

K1: Virus screening kit by culture or PCR

Documents to download

• information note (N23-INTGB)
• information note (N23-INTGB)

Methodology

Real-time PCR

Turnaround time

6 days