False-Positive HIV Test Results More Likely Among Patients With Active COVID-19

Patients with polymerase chain reaction (PCR)-confirmed SARS-CoV-2 are more likely to have false-positive fourth-generation HIV test results, according to study results published in Clinical Infectious Diseases.

Researchers conducted a retrospective, cross-sectional study from March 2020 to January 2022 at the Henry Ford Hospital in Detroit, Michigan. Eligible patients underwent PCR testing for SARS-CoV-2 within 2 weeks of being tested for HIV infection via fourth-generation assay. Patients who tested positive for HIV infection were assessed and divided into groups. The groups included patients with false-positive results, true-positive results, and presumptive-negative results.

Among patients included in the analysis with PCR-confirmed COVID-19 infection, the mean age ranged between 45.6 and 47.7 years, 53.9% to 73.3% were Black, and the majority were unvaccinated against COVID-19 infection (range, 84.2%-94.1%).

Overall, 31,575 patients had presumptive-negative HIV test results, 248 had true-positive results, and 87 had false-positive results. Patients with false-positive results had the highest rate of COVID-19-positive test results (19.5%), followed by those with presumptive-negative results (11.3%; P =.016) and those with true-positive results (7.7%; P =.002).

After adjustments for age, sex, race, ethnicity, pregnancy, and COVID-19 vaccination status, only false-positive HIV test results were significantly associated with PCR-confirmed COVID-19 infection (odds ratio [OR], 4.22; 95% CI, 1.84-9.67; P =.001). These findings did not significantly differ after pregnancy status was removed from the analysis.

The researchers found that the rate of true-positive and presumptive-negative HIV test results did not significantly differ by COVID-19 infection status. In addition, logistic regression showed that false-positive HIV tests results were significantly more likely to occur among patients with vs without PCR-confirmed COVID-19 infection (OR, 2.93; 95% CI, 1.44-5.94; P =.003).

Study limitations include the retrospective design and the use of only 1 platform for HIV and COVID-19 testing. Further, patients with negative HIV test results did not undergo viral load testing unless acute infection was suspected.

According to the researchers, “[A]cute COVID-19 should be considered as a potential etiology for an FP [false-positive] fourth-generation HIV test.”