Increase in False Positive Fourth Generation HIV Tests in Patients with COVID-19 Disease

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Clinical infectious diseases


BACKGROUND: We observed an increase in the frequency of false positive (FP) HIV test results correlating with SARS-CoV-2 prevalence, which led us to measure FP rates of a laboratory-based fourth generation HIV antigen/antibody test among those with polymerase-chain reaction (PCR)-confirmed infection with SARS-CoV-2 compared to the FP rate of those testing PCR-negative for SARS-CoV-2.

METHODS: All those PCR tested for SARS-CoV-2 result within 2 weeks of a HIV fourth generation assay were selected. Positive HIV fourth generation assays were independently reviewed and divided into groups of FP, true positives (TP), and presumptive negatives (PN). Variables included age, race, ethnicity, gender, pregnancy, and COVID-19 immunization status. Associations with positive SARS-CoV-2 tests were assessed using linear logistic regression. A multivariate logistic regression was used to assess sets of variables.

RESULTS: There were 31,910 medical records that met criteria. The frequency of SARS-CoV-2 positive tests was then calculated in groups of HIV TP, FP, and PN. In total, 31,575 patients had a PN HIV test result, 248 patients had a TP, and 87 patients had a FP. Those with HIV FP tests had the highest percentage of COVID-19 positive test results at 19.5%, which was significantly higher than HIV PN (11.3%; p = 0.016) and HIV TP (7.7%; p = 0.002). After adjustment for all covariates, only FP HIV was significantly associated with COVID-19 (odds ratio 4.22; p = 0.001).

CONCLUSIONS: This study reveals those patients with positive SARS-CoV-2 PCR tests are significantly more likely to have a FP fourth generation HIV test than those with negative SARS-CoV-2 PCR tests.

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ePub ahead of print