The most commonly used syphilis tests screen for an antibody to the syphilis organism. Lupus patients sometimes have a very similar antibody. This similar antibody, the antiphospholipid antibody (aPL), can cause an incorrect positive result on a syphilis test. If the doctor suspects that the patient may not really have syphilis, he may choose to then run a different, more complicated and expensive test that checks specifically for the syphilis organism.

False positive tests are rare - though there are instances and conditions where they can occur. For example, some tissues in a non-pregnant woman can produce hCG, though the levels are usually so low they are not detectable by home pregnancy tests (though our tests are the most sensitive on the market). Secondly, research indicates that half of all "conceptions" (fertilized eggs) do not go forward as a developing pregnancy.

There are 4 possible test results: "negative", "positive", "indeterminate", or "result not available." A "negative" test result means antibodies to the hepatitis C virus were not found in your test sample and it is extremely unlikely that you have been infected with the hepatitis C virus.

Yes. A false positive test means the test looks as if it is positive, but it is really negative. This happens more often in persons who have a low risk for the disease for which they are being tested. For example, false positive anti-HCV tests happen more often in persons such as blood donors who are at low risk for hepatitis C.

A false positive hearing screening test result is when a baby does not have a hearing loss but the newborn does not pass the hearing screening. Hearing screening tests are not meant to diagnose hearing loss in infants. Instead, they are meant to find all infants that might have a hearing loss. Because they are not a diagnostic test, hearing screening tests sometimes misidentify infants as having a hearing loss.

It is possible to get a false positive test result. This happens when a doctor or laboratory has not performed a confirmatory antibody test before giving people their results. When a person has an antibody test, the lab usually runs two different kinds of tests. One is called an EIA test which is highly sensitive. It can sometimes overreact, so a positive result with the EIA is usually followed up with a RIBA test which is a sophisticated, highly-specific, antibody test.

Yes, a false positive test means the test looks as if it is positive, but it is really negative. This happens more often in people who have a low risk for the disease. It is important to confirm the test result a second time.

Yes, this happens when the person tested may have an early infection. He or she may not have developed antibody levels high enough that the test can measure. In addition, some people may lack the immune response necessary for the test to work well.

It is important to bear in mind that common diseases, such as atrial fibrillation and stroke, occur as a result of the interplay of both environmental (including lifestyle and other health and medical conditions) and inherited risk factors. As a result, having a specific genetic risk factor for a common disease does not mean that one will necessarily develop the disease; and not having a certain risk variant does not eliminate the possibility of developing the disease.

It is very important to realize that because there are a number of risk factors of atrial fibrillation, including both genetic and lifestyle/health factors, receiving a negative result for the deCODE AF? test does not mean that one is at low or no risk of AF. Back to top of page

It means a laboratory could not confirm the presence of Hepatitis C antibodies in a particular blood sample. It could mean that an individual may be in the process of converting from being negative to being positive. It could also be due to other medical factors. In either case, it is recommended that the individual be re-tested.

A "false positive" occurs when an initial tests indicates that a person does have WNV or EEE, but a later, more specific tests indicates that the person does not actually have the infection. While it is important for the Maine CDC to get an accurate picture of where people are being infected in order to focus prevention and control efforts, the result does not have a great impact on the individual person. There is no specific treatment that the person would receive due to WNV or EEE.