Findings of new study have clinical implications for patients on treatment
The initiation of antiretroviral therapy (ART) during acute HIV infection (AHI) may impact the development of antibodies to HIV, affecting the ability of diagnostic tests to detect HIV infection, according to a study published this month in Clinical Infectious Disease.
Scientists tested the sensitivity of several diagnostic technologies using samples drawn from participants in MHRP and Thai Red Cross’s RV254 acute infection study, in which individuals in the acute HIV infection stage are identified and immediately begin ART, some within days of HIV exposure. Blood was taken at ART initiation and at 12 and 24 weeks following treatment using standard second-, third- and fourth-generation immunoassays and Western blot.
While fourth-generation immunoassay was the most sensitive at detecting AHI prior to ART, third-generation immunoassay was the most sensitive during treatment. Inconsistent results during treatment were observed to at least one test type in 25% of study participants.
“Findings showed that when ART is initiated during AHI, antibodies to HIV may fail to develop, and the HIV diagnostic tests may be falsely negative,” said Dr. Jintanat Ananworanich, RV254 protocol chair and the paper’s senior author. “While it’s uncommon to perform HIV testing on individuals receiving treatment, there maybe instances such as re-location or doubt about testing results where re-testing may be necessary and could lead to erroneous results given these findings. This should not be mistaken for cure and people should remain on their HIV medications.”
Given the ability of the fourth generation test to detect AHI, its increasingly wide-spread use and recommendations for initiating ART as early as possible following infection, the study’s authors recommend caution in the use of routine diagnostic assays in ART treated patients.