Rapid screening tests may not reliably diagnose HIV in natural HIV controllers, leading to false-negative test results in some patients, according to recently published study findings.
“This study was prompted by frequent questions from clinicians asking if patients who naturally control infection could have [a] false-negative diagnosis of HIV infection, and so if the diagnosis could be missed in such patients,” Véronique Avettand-Fenoel, PharmD, PhD, from the clinical microbiology laboratory at Necker Hospital in Paris, told Infectious Disease News.
Avettand-Fenoel and colleagues tested blood samples from 85 HIV controllers who enrolled in a cohort with the French National Agency for Research on AIDS and Viral Hepatitis CO21 between 2009 and 2017.
Aventtand-Fenoel summarized the results of the study, explaining that among well-characterized and selected patients controlling HIV without ART over several years, 6% had a negative rapid screening test. These tests are “increasingly being used, including by patients themselves in settings ‘outside of the laboratory,’” the researchers wrote in the study.
Additionally, the authors said that low antibody response made results difficult to interpret in 25% of cases, especially in a nonlaboratory setting.
According to the study, nine HIV controllers had at least one positive HIV RNA load during follow-up with an ultrasensitive assay. These viral loads were then positive in one of nine to three of five samples. The researchers found that rapid screening tests were negative in 4% of cases, whereas samples from 21 cases were weakly reactive with a very faint band. The study showed that Western blots were positive in 94% of cases and indeterminate in 6%. These tests presented three HIV-1 bands in 3.5% of cases, six bands in 4.7%, seven bands in 3.5%, eight bands in 3.5%, nine bands in 4.7%, and 10 bands in 80.1%.
“In conclusion, our results show that the [rapid screening test] may not be reliable in the context of natural control and very low immune stimulation over a period of several years,” the researchers concluded. “HIV diagnosis in [HIV controllers] can be difficult, and quantification of HIV DNA with ultrasensitive assays is sometimes needed to definitively confirm infection.” – by Caitlyn Stulpin
Disclosures: Avettand-Fenoel reports receiving personal fees from ViiV Healthcare and support for participation in programs and conferences from ViiV and Janssen. Please see the full study for all other authors’ relevant financial disclosures.