Syphilis

CONFIRMATION TESTING

In most Canadian provinces, the preferred screening syphilis test is an enzyme immunoassay (EIA). If positive, it will be usually be followed by a Treponema pallidum particle agglutination assay (TPPA) confirmation test and a Rapid Plasma Reagin (RPR). A positive TPPA suggests either a current or past infection (it usually remains reactive for life), while RPR titers correlate with disease activity. Any positive syphilis result should be discussed with an Infectious Diseases specialist.

In the case of an isolated EIA result (EIA+, TPPA-, RPR-), even if a false-positive is the most likely explanation, follow-up testing 2-3 weeks later is indicated to make sure it is not due to an early infection.

Refer to the Diagnostic Algorithm used at the Calgary Refugee Health Program for positive syphilis serology results (recommendations may vary depending on the province).

 

EVALUATION OF PATIENTS WITH SYPHILIS

All confirmed cases of syphilis should be met in person. They should be asked about any previous history of syphilis diagnosis or treatment. Physicians should counsel patients about syphilis transmission and inquire about recent sexual contacts. A full physical examination should be performed with a specific focus on the genital (look for chancres, warts and regional lymphadenopathy), skin (including palms and soles), neurological (for signs of late neurosyphilis), and cardiac (for tertiary syphilis) exams. If not already done, the patient should also be screened for other sexually transmitted infections.

 

LATE LATENT SYPHILIS TREATMENT

Late latent syphilis (≥1 year) is the most common form of syphilis diagnosed in refugee patients. Whereas primary, secondary and early latent syphilis infections are treated with a single dose of long-acting benzathine penicillin G 2.4 mu IM, late latent syphilis is treated with long-acting benzathine penicillin G 2.4 mu IM weekly for 3 consecutive weeks. Treatment should always be discussed with an Infectious Diseases specialist.

 

>> Refer to the Canadian Guidelines on Sexually Transmitted Infections for more information on the diagnosis and treatment of syphilis infections.