Ambiguous HIV test results in people taking PrEP are rare, and handling such cases is tricky, researchers noted in Open Forum Infectious Diseases.
After reviewing the literature, researchers compared three strategies that can be followed until further testing provides definitive results: continue PrEP, start antiretroviral treatment ART, or stop PrEP.
There are potential risks to each approach. If PrEP is continued, drug resistance may develop, the authors stated. In this scenario, rapid follow-up testing to minimize the time on PrEP while living with HIV is important. If antiretrovirals are started, the person may experience side effects and insurance may not cover the medications in the absence of an HIV diagnosis. Stopping PrEP would lead to a rapid increase in viral replication if the person is, in fact, living with HIV. This would make a reliable diagnosis easier to obtain, but has ramifications both for a confirmed positive (due to a lack of protective benefits from antiretroviral use during acute infection) and a false-positive (due to a period of time in which the person had less protection from HIV infection).
Study authors recommended that health care providers discuss these options with their patients and jointly decide on the best approach, given the patient's specific circumstances.