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What Causes False Negative Results For Syphilis?
Question: can a blood test for std miss showing syphilis or be misread to show no disease
Brief Answer:
Yes it may occur
Detailed Answer:
Hi, Welcome to HealthcareMagic,
For Syphilis there are screening test and confirmatory test both are available.
Screening test may give false negative as well as false positive results. RPR (rapid plasma reagin) or VDRL (venereal disease research laboratory) is a screening test for syphilis. It looks for antibodies that are present in the blood of people.
False negative results occurs due to excess of antibody in the serum samples being examined. This prevents the required flocculation formation and gives negative results. The incidence of this phenomenon is 2%.
he VDRL and RPR, are reactive in 78 percent and 86 percent of patients with primary syphilis.Become positive within approximately four to six weeks after infection or one to three weeks after the appearance of the primary lesion. Thus, these tests can be negative in early syphilis, when patients have lesions.
In patients with strong clinical suspicion screening tests are verified with specific treponemal test.The specific treponemal tests are the micro-hemagglutination assay for Treponema pallidum (MHA-TP) and the fluorescent treponemal antibody absorption (FTA-ABS) test.
Hope this will clear your facts.
Thanks
Yes it may occur
Detailed Answer:
Hi, Welcome to HealthcareMagic,
For Syphilis there are screening test and confirmatory test both are available.
Screening test may give false negative as well as false positive results. RPR (rapid plasma reagin) or VDRL (venereal disease research laboratory) is a screening test for syphilis. It looks for antibodies that are present in the blood of people.
False negative results occurs due to excess of antibody in the serum samples being examined. This prevents the required flocculation formation and gives negative results. The incidence of this phenomenon is 2%.
he VDRL and RPR, are reactive in 78 percent and 86 percent of patients with primary syphilis.Become positive within approximately four to six weeks after infection or one to three weeks after the appearance of the primary lesion. Thus, these tests can be negative in early syphilis, when patients have lesions.
In patients with strong clinical suspicion screening tests are verified with specific treponemal test.The specific treponemal tests are the micro-hemagglutination assay for Treponema pallidum (MHA-TP) and the fluorescent treponemal antibody absorption (FTA-ABS) test.
Hope this will clear your facts.
Thanks
Above answer was peer-reviewed by :
Dr. Yogesh D
thanks. so do you have to actually come in contact with a lesion to contract the disease? the lesions appear on the part of the body that came in contact with other lesion?
Brief Answer:
See below
Detailed Answer:
Hi, welcome again,
Yes you need to be in contact with a lesion to get the infection, or any contact with the bacteria causing the lesion too can cause infection. The most common way of getting infection by having sexual contact with an infected person. The infected person can pass the bacteria from infected skin or mucous membranes (linings), usually your genital area, lips, mouth, or anus, to the mucous membranes or skin of sexual partner.
It can also transmitted from infected mother to baby or infected blood or blood products.
Primarily the lesion appears at the location where syphilis entered the body.
secondary syphilis may appear as spots both on the palms of the hands and the bottoms of the feet or any other site of body.
Hope this clears your facts.
Thanks
See below
Detailed Answer:
Hi, welcome again,
Yes you need to be in contact with a lesion to get the infection, or any contact with the bacteria causing the lesion too can cause infection. The most common way of getting infection by having sexual contact with an infected person. The infected person can pass the bacteria from infected skin or mucous membranes (linings), usually your genital area, lips, mouth, or anus, to the mucous membranes or skin of sexual partner.
It can also transmitted from infected mother to baby or infected blood or blood products.
Primarily the lesion appears at the location where syphilis entered the body.
secondary syphilis may appear as spots both on the palms of the hands and the bottoms of the feet or any other site of body.
Hope this clears your facts.
Thanks
Note: Consult a Sexual Diseases Specialist online for further follow up- Click here.
Above answer was peer-reviewed by :
Dr. Pradeep Vitta
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