A false positive result is when a diagnostic test is positive but is wrong. In the case of HIV, we do not know that it is an incorrect result until we do a confirmatory test with a negative result. It is a very unpleasant and stressful situation for the patient and should be avoided as much as possible.
What are the main causes of a false positive result in HIV?
A colloquial way of describing it is that there is something (other than HIV) that “stimulates” the patient’s immunity. At Open House we take extra precautions to minimise the false positive rate in our tests, this knowledge we have acquired through our 16 years of experience diagnosing HIV.
elow are 7 situations that represent 95% of the risk factors that we have identified in Open House:
- Herpes – having cold sores or an active herpes infection is the main cause of having a false positive result for HIV.
- Syphilis – in someone with active syphilis we do not test for HIV until the syphilis is properly treated.
- Other STIs – our first false positive HIV test in 2007 was in a patient with an active gonorrhoea infection.
- Other infections – any other active infection can cause this type of false positive result.
- Fever, pregnancy and autoimmune diseases.
So I can’t do HIV tests if there are any active risk factors?
For several years, at Open House we have had an HIV test called PCR, it is a test with practically no false positives and it is a way of testing for HIV in people with these risk factors. If you have experienced a possible false positive result and want to talk to us, write to us on the contact form or call our clinics.
Dr. Atef Souied Espada