Syphilis infection rates are increasing in subgroups, especially among men who have sex with men, with a total of 13,106 cases of primary and secondary syphilis diagnosed in the United States in 2011 according to the CDC. Syphilis infection is an STI caused by the bacteria Treponema pallidum. Clinical findings and serological tests are often used for syphilis diagnosis.
No specific serologic test is however not sufficient for diagnosing syphilis. Thus, the detection of 2 types of antibodies (treponemal antibodies and non-treponemal antibodies) are required for the serological diagnosis of syphilis. Syphilis diagnosis paradigm has shifted recently in many centers to detection with a treponemal antibody test and if the treponemal antibody test is positive, we at bigmanlab switch to a nontreponemal antibody diagnosis.
What is a syphilis test?
Detection and diagnosis of syphilis bacteria is done through a syphilis test. One of the most familiar sexually transmitted infection is syphilis. Syphilis is transmitted through vaginal, anal, or oral sexual contact with someone who is infected with the syphilis bacteria. It can equally be transmitted from a pregnant woman to her baby. Antibodies specific for syphilis are detected with treponemal tests.
These tests include immunoassays, various EIAs, rapid treponemal, immunoblots TP-PA, and chemiluminescent tests. Non-treponemal antibodies appear after Treponemal antibodies appear. Even after successful treatment, they usually remain detectable for life. Do a non-treponemal titer test, if you are using a treponemal test to screen and it is positive. This confirmatory syphilis diagnostic test will guide patient treatment management decisions.
What samples are used in syphilis diagnosis?
Syphilis disease can be diagnosed by testing a sample of:
Blood:
The presence of antibodies, which your body produces to fight infection can be confirmed with a blood tests. Blood tests can detect past or current infections since the antibodies against the bacteria that cause syphilis stay in your body for years.
Cerebrospinal fluid analysis:
Health care providers may also recommend taking a sample of your cerebrospinal fluid through a lumbar puncture, if you suspect you have nervous system complications from syphilis.
Bigmanlab often offers services for couples to help them notify your sexual partners that they may have syphilis disease.
Syphilis test purpose
Identifying syphilis infection is the goal of syphilis diagnostic tests. Syphilis tests may be ordered to monitor, diagnose, or detect:
Syphilis diagnostic tests:
Recommended if you show symptoms or signs that may be due to syphilis infection. Even if your symptoms aren't specific or severe, a doctor may recommend a test for syphilis because syphilis can cause a variety of symptoms. The diagnosis of syphilis generally requires two tests: a primary screening diagnosis and a later confirmatory diagnosis.
Syphilis screening:
People who do not have symptoms or signs of the syphilis disease are usually screened. Those at high risk of developing syphilis benefit from screening include and those who are more likely to spread syphilis to others.
After treatment follow-up:
Making sure you are responding to treatment as prescribed is very important. Laboratory blood tests to confirm response to treatment and physical exam to assess any changes in symptoms you are seeing are some tests used for monitoring.
Syphilis diagnostic tests
Direct detection testing methods:
There are several tests that can be used to detect organisms directly even though these methods are not commonly available. This includes direct fluorescent antibody tests for T pallidum, PCR, and dark field microscopy.
This testing method can help diagnose syphilis before a serologic reactions, in some cases. Most clinical centers however rely on serological tests and clinical manifestations since they lack access to these methods.
Serology diagnosis of syphilis:
This syphilis testing method requires the use of two separate tests: the non-treponemal test, which uses a nonspecific antigen called cardiolipin, and the confirmatory test, which uses a Treponema pallidum specific antigen.
Because all tests have limitations, including the possibility of a false positive test result, using only one type of test is not sufficient for diagnosis. A variety of conditions unrelated to syphilis, including injection drug use, aging, and autoimmune disorders may be the cause of false-positive nontreponemal test results.
Non-treponemal antibody test:
Antibodies that causes syphilis but are not specific for the Treponema pallidum bacterium are detected with this test. Although the antibodies are also produced in response to other conditions, usually they are produced when a person has syphilis. After successfully treating a syphilis infection, people often test negative for these antibodies.
A positive result must be confirmed with another type of test, but the non-treponemal antibody test is often used as the primary screening test, and. Several non-treponemal antibody tests types exist that can be used to monitor and detect syphilis:
RPR (Rapid plasma reagin) test:
The reagin antibodies that are often produced by the body in response to a syphilis bacterial infection are detected with this test.
VDRL (Venereal Disease Research Laboratory):
Antibodies produced within a week or two after the initial sores is developed by an infected person is measured with VDRL test. Spinal fluid and blood can be used to do VDRL test.
Treponemal antibody syphilis test:
Antibodies produced only after infection of the body with the syphilis bacteria are detected with this test. This type of antibody usually lasts indefinitely and can be detected in the body earlier than the non-treponemal antibodies.
After completing your syphilis treatment, you can still test positive for Treponemal antibodies. Thus treponemal antibody test doesn’t distinguish between past and current syphilis bacterial infections.
Common syphilis antibodies diagnostic tests to detect include:
- FTA-ABS test (Fluorescent Treponemal Antibody Absorption Test)
- TP-PA test (Treponema pallidum particle agglutination test)
- MHA-TP (Microhemagglutination test for antibodies against Treponoma pallidum)
- CLIA test (Chemiluminescent Immunoassays)
- TPHA test (Treponomal pallidum hemagglutination test)
- TP-EIA (Treponomal pallidum enzyme immunoassay)
At bigmanlab, a health care provider in some cases will use a test that looks for the actual bacteria, not the antibodies. This test can only be done in a specialized laboratory and thus are rare.
A non-treponemal antibody test in most cases is used to detect syphilis, while a treponemal syphilis test is used to confirm the syphilis diagnosis. Your doctor in some cases may first test you with a treponemal antibody test and later do a non-treponemal antibody test for confirmation. This test strategy is refered to as reverse order test.
Less common methods for detecting syphilis analyze its genetic material or look for the bacterium itself. These includes:
PCR test (Polymerase chain reaction):
This test detects DNA, from the bacterium Treponema pallidum.
Dark-field microscopy:
A sample of fluid from a skin wound or lymph node is used in this method of detecting syphilis. Using a special microscope, the Treponema pallidum bacterium appeare bright against a dark background when the samples are analyzed.
Geting tested for syphilis infection
A blood sample is often used to test for syphilis. Fluid taken from a syphilitic ulcer or cerebrospinal fluid can be used to perform the test. A special procedure called a lumbar puncture is used to collect cerebrospinal fluid.
At bigmanlab a healthcare professional is responsible for collecting the samples.
Before the test:
A syphilis test which uses a sample of fluid from a wound or blood requires no preliminary preparations before testing. Syphilis can affect the nerves, spinal cord, and brain at any stage. We often order a cerebrospinal fluid (CSF) test for syphilis if your symptoms suggest that syphilis might be affecting your nervous system and brain. You may be asked to go to the bathroom to empty your bowels and bladder before a lumbar puncture.
During the test:
Drawing blood from a vein on the back of the hand or inside the elbow is done during sample collection. The site is first cleaned and then an elastic band is usually tied around your arm to increase flow of blood, a needle is then inserted into the vein and in a vial or tube blood is collected. The rubber band is removed once enough blood has been collected before removing the needle.
Usually fluid samples gotten from a wound is used for a syphilis test, the technician uses a brush or swab to remove the fluid from the area of bacterial infection. Although very brief, the collection process is usually uncomfortable.
After the syphilis test:
You may be asked to apply pressure to the injection site once the blood draw is complete, and bandaged to reduce further bleeding. There is a slight risk when fluid samples from sores or blood is drawn. No restrictions exist after completing the trial on resuming normal activities.
After a lumbar puncture, to avoid headaches, you may be asked to lie down for an hour or two after the procedure. You may feel some temporary discomfort and pain at the point where the needle is inserted.
Syphilis Treatment
In its early stages when diagnosed and treated, syphilis is easily curable. The medicine of choice at all stages is penicillin, an antibiotic drug that kills the syphilis bacteria. At bigmanlab we suggest other antibiotic for those allergic to penicillin, or recommend penicillin desensitization.
A single injection of penicillin is the recommended treatment for primary, secondary, or early latent syphilis. You may need an extra dose if you have had syphilis for more than a year. Pregnant women with syphilis are only recommended to take Penicillin. Newborn babies should be tested for congenital syphilis even if the mother was treated for syphilis during pregnancy and, if infected, antibiotics should be used for treatment.
You experience what is referred to as Jarisch-Herxheimer reaction on the first day of treatment. Symptoms and Signs include aches, nausea, chills, headaches and fever. Usually these reactions do not last for more than 24 hours.
