Healthcare providers collect samples of CSF through a procedure known as a lumbar puncture or spinal tap. Then they will insert a spinal needle into the lower spine, which they use to extract a small quantity of CSF. The test can take 3—5 days. However, people who have a high risk of syphilis may want to consider getting routine screening tests about every 3 months.
The VDRL blood test is not always accurate. Infections, such as HIV or pneumonia , as well as other autoimmune disorders, can trigger a false-positive result. If the result is positive, a doctor will perform another test, such as the fluorescent treponemal absorption assay. This test will be able to confirm whether the infection is syphilis. If a person receives a positive result, a doctor will typically perform a treponemal test, which detects the antibodies to the T Pall i dum proteins.
If this is positive, it indicates that syphilis has infected the central nervous system. Sometimes, however, doctors test for syphilis in reverse. They will begin by testing a person with a syphilis-specific treponemal test. If this proves positive, they will follow it up with a nontreponemal test, such as a VDRL. The VDRL test offers a safe and convenient way to screen for syphilis infections. The test itself does not carry any significant risks.
However, there may be some slight complications associated with the process of drawing blood and lumbar punctures. A chancre appears during the primary stage of syphilis. This is when skin rashes and lesions appear. They may occur in the vagina, the anus, or the mouth. Because the sensitivity of nontreponemal tests is lower that that of treponemal tests in the primary stage, a negative nontreponemal test in an HIV-infected individual with a genital lesion cannot exclude primary syphilis.
It may be useful to consider both a nontreponemal and a nonreflexed treponemal test as a diagnostic strategy in newly infected persons with suspicious lesions. Unusual serologic responses have been reported in HIV-infected persons with syphilis.
Most reports involved higher than expected serologic titers, but false-negative serologic results and delayed appearance of sero-reactivity have also been reported, albeit rarely. Nevertheless, serologic tests appear to be accurate and reliable for the diagnosis of syphilis and the evaluation of treatment response in most HIV-infected patients. The clinician should seek confirmatory evidence for the diagnosis from any available source, including the patient's history, clinical findings, direct examination of lesion material for spirochetes, and serologic tests for syphilis.
Reports of nontreponemal antibody test results should be quantitative and describe the lowest dilution i. The interaction of syphilis and HIV infection is complex and remains the subject of ongoing research. Although case reports have suggested that coexisting HIV infection may alter the natural history of syphilis, only a few such effects have been demonstrated in large observational studies.
Initial serologic responses to early syphilis were shown to be generally equivalent in HIV-negative and HIV-positive patients. Nevertheless, both treponemal and nontreponemal serologic tests for syphilis are accurate in the majority of patients with syphilis and HIV co-infection. Irrespective of sign and symptoms, all HIV-positive patients should have baseline VDRL screening and follow-up at 3 months to rule out the possibility of false-negative results, as seroconversion generally takes about 4—6 weeks after infection.
Repeat testing is indicated in both instances. HIV is considered to be one of the important causes of false-positive reaction to syphilis serology; but this conception needs to be reinterpreted as most of the studies on syphilis serology in HIV positives have used populations that include those involved in IV drug use, a behavior that is an independent risk factor for false-positive serology.
Further prospective study on the HIV-infected patients with biological false-reactive VDRL results to assess the seroconversion pattern and possible silent abnormality is recommended. There is no ideal test of cure of syphilis available that can be carried out within days or weeks after treatment to determine the status of a patient.
Patients should have serological tests for syphilis done on the day treatment is initiated. When serological test is negative, patient is assured to be cured.
Generally, seropositivity is achieved in majority of the patients with primary syphilis in about 12 months after the treatment and in those with secondary syphilis in about 24 months. Seroconversion is more rapid after therapy if duration of infection is short and initial titer is low. As seroconversion is a slow process requiring months to years, the rate of decline is a better indicator of therapeutic response.
A 4-fold decrease in titer is considered as good response, and this should occur within months after therapy in patients with primary and secondary syphilis and within 12 months in patients with early latent syphilis.
There is no satisfactory monitoring test available for nontreponemal test-negative late disease. Nonreactive serologic tests and normal clinical evaluation cannot exclude incubating syphilis.
Some experts recommend that HIV-infected patients be followed more closely at 3-month interval. Persistence, recurrence, or development of clinical signs or symptoms of syphilis in the absence of reinfection.
Sustained greater than 2 weeks fourfold two dilutions increase in the nontreponemal test titer assuming the same test type was used [e. Failure of the initial nontreponemal test titer to decrease fourfold two dilutions by 6—12 months for primary, secondary, or early latent syphilis and by 12—24 months for late latent syphilis or syphilis of unknown duration. Syphilis has been referred to as the great imitator due to its wide variety of clinical presentations. Therefore, prompt diagnosis and treatment are essential not only to lower transmission rates, but also to avoid the complications seen in the later stages of the disease.
However, when test result that is to be conveyed to the patient in a community where a limited resource is available, we need to inform the patient that a definitive diagnosis is only possible by performing, dark field examinations and direct fluorescent antibody DFA test. VDRL is just one of the tests to make an presumptive diagnosis. The use of only one type of serologic test is insufficient for diagnosis, because false-positive nontreponemal test results are sometimes associated with various medical conditions and situations unrelated to syphilis as mentioned above.
It is not easily cultured, and cannot grow on artificial media. This is a nonspecific test but it is useful in following treatment, since the antibody titer declines on successful therapy. It also impresses on nonvenereologists the need to cautiously order and interpret serological tests for the demonstration of syphilis. This subsumes quantifying the VDRL among the infected, and the use of modern tests to determine the intensity of syphilitic process.
Despite the higher sensitivity of treponemal tests, they have not been recommended for initial screening in the many countries, primarily because of cost.
It is always advisable to interpret properly before giving any diagnosis to avoid any legal complications in future, so also for the psychological well-being of the patient. In accord with all diagnostic methods, a final diagnosis should not be made on the basis of result of a single test, but should be made on co-relation of test results with other clinical findings. Source of Support: Nil.
Conflict of Interest: Nil. National Center for Biotechnology Information , U. Journal List Indian J Dermatol v. This is due to the transfer of antibodies from the infected mother to the child. In such case, the test are normally repeated after a month to confirm the result.
Most people don't feel comfortable sharing the details of their sexual experiences, but the doctor's office is one place where you have to provide this information so that you can get the right care. If the doctor wishes to make an exception, he will inform the patient before the test.
Should the doctor suspect that the syphilis infection has spread to the brain, a test of the spinal fluid may be ordered in addition to the blood test. The most prudent preparation will be to follow the doctor's instructions on how to prepare for this test. Usually, all that will be needed for the VDRL test is allow the healthcare professional to draw blood. Blood is generally drawn from a vein at the crease of the elbow or the back of the hand.
This blood sample will then be sent to the laboratory and tested for the antibodies that may have been produced as a result of a syphilis infection. These screening tools have demonstrated a high accuracy for the clinical diagnosis of primary syphilis. This is a nonspecific test but which is useful in following treatment, because the antibody titer declines upon a successful therapy.
Nontreponemal tests are rapid, simple, and inexpensive. They are the only tests recommended to monitor the course of disease during and after treatment. Nontreponemal tests can also serve to detect reinfection.
The main limitations of nontreponemal tests are their reduced sensitivity in primary syphilis and late latent syphilis, false-positive results due to cross reactivity, and the potential for false-negative results due to prozone phenomenon.
Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your provider about the meaning of your specific test results. A positive test result means you may have syphilis. If the test is positive, the next step is to confirm the results with an FTA-ABS test, which is a more specific syphilis test. The VDRL test's ability to detect syphilis depends on the stage of the disease.
The body does not always produce antibodies specifically in response to the syphilis bacteria, so this test is not always accurate. There is little risk involved with having your blood taken. Veins and arteries vary in size from one person to another and from one side of the body to the other.
Taking blood from some people may be more difficult than from others. Syphilis Treponema pallidum.
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