Interpret syphilis serology results in consultation with an experienced colleague. Health care professionals should consider yaws, pinta, bejel and Lyme disease in the differential diagnosis when NTT and/or TT are positive. Note: The following information is provided for general guidance. Refer to the follow-up section for recommendations related to monitoring of NTT results post treatment. If these diagnoses are suspected, it is appropriate to add a TT to the initial screen or, in the case of primary syphilis, to repeat both the TT and NTT after two (2) to four (4) weeks, when testing may have been done before seroconversion(incubation period). The NTT may be non-reactive in cases of early primary, late latent syphilis or tertiary syphilis. NTT antibody titres usually correlate with disease activity and can help stage infection, monitor response to treatment and detect re-infection. False positive serologic tests for syphilis may occur with certain conditions such as collagen-vascular disease, pregnancy, injection drug use, Lyme Disease or a condition inherent to the test or testing technique. Once reactive, TTs usually remain reactive for life regardless of treatment, although 15% to 25% of people will serorevert if treated during the primary stage Footnote 7. Although EIA is highly sensitive, it may lack specificity therefore if the EIA screen is positive, a second treponemal-specific test can confirm the diagnosis. Several commercial EIAs have been developed to detect IgG or IgM to specific T. TTs such as the treponemal-specific enzyme immunoassay (EIA) are more sensitive tests for syphilis. A second confirmatory TT may be done in some laboratories. An alternative approach is to use a reverse sequence algorithm, which uses a TT to screen and a quantitative NTT to confirm the positives. The traditional algorithm uses a non-treponemal test (NTT) -typically a rapid plasma reagin (RPR) test- to screen sera, followed by one (1) or two (2) TTs on the positive samples. Consult your local laboratory regarding testing protocols. Most provinces and territories use the reverse algorithm. Two (2) types of serologic screening algorithms are used in Canada Footnote 6. Serologic testing should always be done regardless of suspected stage. Refer to the Canadian Paediatric Society's article Congenital syphilis: No longer just of historical interest for information about how to manage infants born to mothers with reactive treponemal tests (TTs) during pregnancy. Test infants presenting with signs or symptoms compatible with early congenital syphilis even if their mother was seronegative at delivery because they may have become infected near term. At 20 weeks gestation with a detailed obstetrical ultrasound Footnote 2, Footnote 3, Footnote 4, Footnote 5.Assessment for possible congenital syphilis should be done: Pregnant people diagnosed with infectious syphilis should be managed in consultation with an obstetric/maternal-fetal specialist. Depending on the stage and clinical presentation, diagnostic testing may be done on blood, lesions and/or samples of cerebral spinal fluid. HIV, as per the recommendations in the HIV Screening and Testing GuideĬonsider a diagnosis of syphilis in anyone with signs or symptoms compatible with syphilis.People being evaluated or treated for a syphilis infection should be screened for: Syphilis increases the risk of acquisition and transmission of HIV Footnote 1. Any person with STBBI risk factors should be screened for STBBIs and treated appropriately to prevent transmission and reinfection. STBBI screening varies by age, gender/sex, medical and sexual history. Screen all people who deliver a stillborn infant after 20 weeks gestation. Repeat screening at 28-32 weeks of pregnancy (or as close to this interval as possible) and again at delivery:Ĭonsider more frequent screening for pregnant people at high risk. Universal screening is recommended for pregnant people during the first trimester or at first prenatal visit. Health care providers should follow local public health recommendations and laboratory screening protocols during a syphilis outbreak. Screening is recommended for anyone presenting with risk factors for syphilis to prevent complications, transmission and reinfection. Individuals with these conditions should be managed by or in consultation with an infectious disease specialist or an experienced colleague. Some information about neurosyphilis and congenital syphilis is included, however their treatment is outside the scope of this document. This guide is about management of primary, secondary, latent and tertiary syphilis.
0 Comments
Leave a Reply. |