Performance of the Enzyme Linked Fluorescent Assay in Diagnosis of HIV Infection; Comparative Evaluation with other Methods

Background: Our study aimed to investigate the role of the enzyme linked fluorescent assay (ELFA) method in the diagnosis of Human Immunodeficiency Virus (HIV) infection by comparing it with enzyme-linked immunosorbent assay (ELISA) and chemiluminescent microplate immunoassay (CMIA) methods and its role in the HIV diagnostic algorithm and to update the recommended algorithm for HIV testing. Methods: We evaluated 101 HIV-reactive and 101 HIV-negative specimens. All samples were studied with the methods of anti HIV1/2 test micro-ELISA, ELFA, and CMIA. At the same time, HIV RNA PCR and western blot (WB)/rapid immunochromatographic test (RICT) were also studied with the same samples. Results: All HIV RNA and WB positive samples (n = 101) were positive with micro-ELISA, CMIA and ELFA. Twenty-five negative samples of HIV RNA and WB were positive with micro-ELISA and CMIA, while just 6 samples were positive with ELFA. When all samples were evaluated together, the false positivity rate of the ELFA method was found to be 5.9%, and the false positivity rates of the micro-ELISA and CMIA methods were determined to be 31.7% and 30.7%, respectively. Conclusions: It was determined that there is a high level of agreement between the ELFA method and confirmation tests. It was thought that it might take place in the pre-confirmation stage. As can be seen from the results obtained, the false positive rate by ELFA method was found to be about five times lower than that of micro -ELISA and CMIA methods. Considering that antigen (p24) and antibody positivity can be given separately with this aspect, it can be considered that there is a confirmation place in HIV diagnosis algorithm.

Automated summary

This study compared the role of the enzyme linked fluorescent assay (ELFA) method with enzyme-linked immunosorbent assay (ELISA) and chemiluminescent microplate immunoassay (CMIA) methods in the diagnosis of HIV infection. It was found that ELFA method had a lower false positive rate and high agreement with confirmation tests, suggesting a potential role in the HIV diagnostic algorithm.