Evaluation of the significance of EBV nucleic acid and serology tests in the management of EBV-related diseases

Abstract

Objective To investigate the relationship between Epstein-Barr virus (EBV) DNA and EBV serology markers and evaluate the clinical application values in different diseases. Methods Plasma samples from 397 diagnosed EBV infection-associated patients and 120 health donors from May 2014 to November 2015 in Wuhan Tongji Hospital were collected. Real-time fluorescent quantitative PCR was performed to detect the levels of EBV-DNA in peripheral blood mononuclear cell and plasma. ELISA was used to detect VCA IgA, VCA IgM, VCA IgG, EA(D) IgG and EBNA IgG antibodies in plasma. The positive rate of EBV-DNA and EBV antibodies were counted in each group according to the detection threshold.Kappa statistic and Spearman sank correlation test were used to analysis the correlation and uniformity between EBV-DNA and EBV serology indicators. Results The positive rate of VCA IgG in patient and health control was 94.2% (374/397) and 93.3% (112/120) respectively (χ2=0.125, P=0.67); The positive rate of EBNA IgG in patient and health control was 95.4% (379/397) and 95.0% (114/120) respectively (χ2=0.045, P=0.807); but the positive rate of VCA IgM was 5.5% (22/397) and 0% (0/120) respectively (χ2=6.9, P<0.01); The positive rate of VCA IgA was 43.3% (172/397) and 9.2% (10/120) respectively (χ2=49.5, P<0.01); The positive rate of EA(D) IgG was 42.0% (167/397) and 7.5% (9/120) respectively (χ2=49, P<0.01). The positive rate of EBV-DNA was 65.5% (260/397) and 16.7% (20/120) respectively (χ2=88.5, P<0.01); The positive rate of EBV-DNA in plasma was 45.8% (182/397) and 5.0% (6/120) respectively (χ2=66.4, P<0.01). Furthermore, the uniformity and Spearman correlation analysis showed that there was no significant correlation between EBV-DNA and EBV serology indicators. The correlation analysis between PBMC EBV-DNA and VCA IgM, VCA IgA, EA(D) IgG showed the Kappa was 0.073, 0.147, 0.073, respectively; the correlation analysis between plasma EBV-DNA and VCA IgM, VCA IgA, EA(D) IgG showed the Kappa was 0.144, 0.369, 0.288, respectively. Thus, the patients were divided into different groups according to the discharge diagnosis, it was observed that the positive rates of EBV-DNA is more than 90% in extra-nodal NK/T cells lymphoma, EBV-associated hemophagocytic lymphoid tissue hyperplasia, chronic active EBV infection and infectious mononucleosis. In nasopharyngeal carcinoma patients, the positive rate of EBV antibodies (VCA IgA and EA(D) IgG) were higher than the detection of EBV-DNA. Conclusions There was no significant correlation between EBV-DNA and EBV serology markers for the same sample. The clinical application values of EBV DNA and EBV serology markers were not identical in nasopharyngeal carcinoma, extra-nodal NK/T cells lymphoma, infectious mononucleosis and EBV-associated hemophagocytic lymphoid tissue hyperplasia. (Chin J Lab Med, 2017, 40: 195-200) Key words: Herpesvirus 4, human; DNA, viral; Serologic tests; Nasopharyngeal neoplasms; Lymphoma