# The application of Electrochemiluminescence Immunoassay (ECLIA) in the detection of HIV infectious markers in blood screening

## TL;DR

This study compares ECLIA with ELISA and Western blot for detecting HIV in blood donors, showing ECLIA's superior accuracy and reliability.

## Contribution

Demonstrates ECLIA's higher specificity and agreement with confirmatory tests, supporting its adoption for HIV blood screening.

## Key findings

- ECLIA showed 81.25% sensitivity and 96.49% specificity in detecting HIV.
- ECLIA had higher positive and negative predictive values compared to ELISA.
- ECLIA demonstrated excellent agreement with Western blot confirmatory results.

## Abstract

This study aimed to analyze ELISA, ECLIA, and Western blot (WB) confirmatory test results for HIV-reactive blood donors, compare ECLIA with fourth-generation ELISA reagents, assess the feasibility of using ECLIA for HIV screening, and provide statistical evidence supporting its adoption in blood collection and supply institutions.

The cross-sectional study was conducted in the Laboratory Department of Yantai Central Blood Station, Shandong, China, from January, 2021 to December, 2023. A total of 130 HIV screening-reactive specimens with ELISA signal-to-cut-off (S/CO) ratios between 0.3 and 0.7 were subjected to ECLIA. Specimens with ELISA S/CO≥1.0, HIV RNA reactivity, or ECLIA S/CO>1 were sent to the Centers for Disease Control (CDC) for WB confirmatory testing. The results were comprehensively analyzed and compared.

Among the 130 reactive specimens, 17 tested positive by ECLIA, while 113 were negative. Of the 510 HIV screen-negative specimens, five were positive by ECLIA, and 505 were negative. ECLIA demonstrated a sensitivity of 81.25%, specificity of 96.49%, positive predictive value of 76.47%, and negative predictive value of 97.35%. ECLIA showed excellent concordance with WB confirmatory results, evidenced by the highest area under the operating characteristic (ROC) curve (AUC). The sensitivities of reagent one, reagent two, and ECLIA were consistent at different cut-off values; however, ECLIA exhibited the highest specificity.

ECLIA exhibits superior agreement with WB confirmatory tests, higher specificity, and positive predictive values compared to ELISA reagents, supporting its widespread use in blood screening.