Outreach Solutions Tactics Articles Events. Utilization Management Algorithms. Test Catalog. Download Test. Useful For Suggests clinical disorders or settings where the test may be helpful An aid in the diagnosis of recent or past Treponema pallidum infection Routine prenatal screening This test is not useful for diagnosis of congenital syphilis.
Nonreactive: No serologic evidence of exposure to Treponema pallidum syphilis. Equivocal: Recommend follow-up testing in 10 to 14 days if clinically indicated. Reactive: Results suggest infection with T pallidum at some point in time. In very early cases of primary syphilis, serology tests for syphilis may be negative.
Results should be considered in the context of all available clinical and laboratory data. Elsevier; 3. The persistence or loss of IgG and IgM antibody specificities for individual polypeptides of Treponema pallidum after therapy for syphilis was examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis SDS-PAGE and by the Western blot technique.
Both IgG and IgM antibodies to as many as 12 treponemal antigens, including a major kdalton molecule, were evident in plasma from patients with untreated primary syphilis. A positive syphilis total antibodies reflexes automatically to RPR. A negative syphilis total antibodies means that past or present syphilis infection is unlikely.
A positive syphilis total antibodies can indicate a past or present infection. Specimens showing positive syphilis total antibodies will be reflexed automatically to RPR.
Successful treatment is generally indicated by a 4-fold or more reduction in RPR titer e. This test should not be used to evaluate response to therapy.
Syphilis is a disease caused by infection with the spirochete Treponema pallidum. The infection is systemic and the disease is characterized by periods of latency. These features, together with the fact that T pallidum cannot be isolated in culture, mean that serologic techniques play a major role in the diagnosis and follow-up of treatment for syphilis.
Syphilis is categorized by an early primary infection in which patients may have nonspecific symptoms and, potentially, genital lesions. Patients tested by serology during the primary phase may be negative for antibodies, especially if testing is performed during the first 1 to 2 weeks after symptom onset. As the disease progresses into the secondary phase, antibodies to T pallidum reach peak titers and may persist indefinitely regardless of the disease state or prior therapy.
Therefore, detection of antibodies to non-treponemal antigens, such as cardiolipin a lipoidal antigen released by host cells damaged by T pallidum may help to differentiate between active and past syphilis infection. Testing for IgM-class antibodies to T pallidum should not be performed during routine pregnancy screening unless clinically indicated. Historically, the serologic testing algorithm for syphilis included an initial non-treponemal screening test, such as the RPR or the venereal disease research laboratory VDRL tests.
Because these tests measure the host's antibody response to non-treponemal antigens, they may lack specificity. Due to the low prevalence of syphilis in the United States, the increased specificity of treponemal assays, and the objective interpretation of automated treponemal enzyme immunoassay EIA and multiplex flow immunoassay MFI , many large clinical laboratories have switched to screening for syphilis using a reverse algorithm.
Specimens testing positive by these assays are then reflexed to the RPR assay to provide an indication of the patient's disease state and history of treatment. Recently, the Centers for Disease Control and Prevention recommended that specimens testing positive by a screening treponemal assay and negative by RPR be tested by a second treponemal test eg, TP-PA.
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