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Syphilis Antibody
Aka: Syphilis Antibody, Syphilis Serology, Syphilis Screening, Syphilis False Positive, Syphilis Testing, Syphilis Diagnosis, Treponema test
- See Also
- Syphilis
- Neurosyphilis
- Syphilis Antibody (Syphilis Serology)
- Dark-field Microscopy
- Sexually Transmitted Disease
- Indication
- Syphilis (Treponema pallidum) detection
- Confirmation of positive Screening Test
- Background
- Antigen Extracts from beef heart (cardiolipin)
- Non-specific Syphilis antibodies bind cardiolipin
- Labs: Tests for detection of Treponemal Pallidum Antibody
- Non-Treponemal Derived Substance precipitates Antibody
- Venereal Disease Research Laboratory (VDRL)
- Rapid Plasma Reagin (RPR)
- Automated Reagin Test (ART)
- Standard Test for Syphilis (STS)
- Treponemal antigen precipitates Antibody
- Fluorescent Treponemal Antibody (FTA-ABS)
- Sensitivity: 80%
- Microhemagglutination - Treponema pallidum (MHA-TP)
- Sensitivity: 65% to 70%
- Labs: Non-Antibody Tests
- Dark-field Microscopy
- Most specific if Chancre or condyloma is present
- Can result in immediate diagnosis in the first week without the 3 week delay witing for IgM to develop
- Accuracy varies with experience of technician
- Protocol: Testing
- Screening
- Syphilis Screening annually for all men who have sex with men
- Syphilis Screening (positive within 3 weeks of developing primary Chancre)
- VDRL (Venereal Disease Research Lab Test)
- RPR (Rapid Plasma Reagin test)
- HIV Screening (test all patients who are positive for Syphilis)
- HIV coinfection with Syphilis is common
- HIV patients are at higher risk of Neurosyphilis
- Negative test with lesions present or other strong clinical indicators
- Repeat screening in 2-3 weeks
- Confirmation of positive Screening Test
- Fluorescent Treponemal Antibody (FTA-ABS)
- Neurosyphilis CSF Evaluation
- See Neurosyphilis
- Indications for Lumbar Puncture with CSF Exam
- All patients with Syphilis and neurologic symptoms
- All patients with serologic or exam findings consistent with treatment failure
- HIV patient specific criteria
- CD4 Count <350 cells/mm3 or
- Rapid plasmin reagin (RPR) >1:32
- Monitoring response to treatment
- Non-Treponemal Antibody test (e.g. RPR) will normalize after treament
- Treponemal tests will remain positive despite treatment
- Interpretation: False Positives (Seen with the non-Treponemal Tests)
- Systemic Lupus Erythematosus
- Malaria
- Infectious Mononucleosis
- Infectious Hepatitis
- Post-vaccination state
- Leprosy
- Brucellosis
- Atypical Pneumonia
- Miliary Tuberculosis
- Typhus
- Pregnancy
- Related Treponemal infection
- Yaws
- Pinta
- Bejel
- Efficacy
- Diagnostic Test Sensitivity in Primary Syphilis
- Dark-field Exam of Chancre: 80%
- Non-Treponemal tests (e.g. RPR): 78-86%
- Treponemal tests (e.g. FTA-ABS): 76-84%
- Diagnostic Test Sensitivity in Secondary Syphilis
- Dark-field Exam of Chancre: 80%
- Non-Treponemal tests (e.g. RPR): 100%
- Treponemal tests (e.g. FTA-ABS): 100%
- Diagnostic Test Sensitivity in Latent Syphilis
- Non-Treponemal tests (e.g. RPR): 95-100%
- Treponemal tests (e.g. FTA-ABS): 97-100%
- Diagnostic Test Sensitivity in Tertiary Syphilis
- CSF evaluation required (see below)
- Non-Treponemal tests (e.g. RPR): 71-73%
- Treponemal tests (e.g. FTA-ABS): 94-96%
- Reference
- Bakerman (1984) ABCs of Interpretive Lab Data, p. 392
- Larsen (1995) Clin Microbiol Rev 8:1-21