Development of a Diagnostic Algorithm for Epstein‐Barr Virus‐Related Diseases: A Retrospective Observational Study

ABSTRACT Epstein‐Barr virus (EBV) is linked to a spectrum of diseases. To investigate the characteristics of various EBV‐associated diseases in China, we conducted a multi‐center retrospective cohort study examining molecular and serological features. EBV DNA copy numbers in plasma and peripheral blood mononuclear cells (PBMCs) were determined using quantitative polymerase chain reaction (qPCR), while four EBV‐specific antibodies were assessed via chemiluminescence immunoassay. Our study included 746 patients with EBV‐related diseases and 350 control adults without EBV‐associated diseases. Among the patient group, EBV DNA was detectable in 97.7% of PBMC samples and 92.6% of plasma samples, significantly surpassing the positivity rates observed in controls (46.7% in PBMCs and 4.6% in plasma). In terms of specific diseases, EBV DNA was positive in PBMCs in almost all the patients across most disease groups, except in nasopharyngeal carcinoma (87.4%), whereas the EBV DNA positivity rates in plasma varied considerably. Most disease groups exhibited low positivity rates for viral capsid antigen (VCA)‐IgM and high positivity rates for EBV nuclear antigen (EBNA)‐IgG. Contrary, infectious mononucleosis demonstrated a high seropositivity rate (94.2%) for VCA‐IgM but a low rate (0.8%) for EBNA‐IgG. EBV DNA in plasma effectively distinguishes patients with EBV‐associated diseases from control subjects, and incorporating PBMC EBV DNA further enhances diagnostic accuracy. In conclusion, our findings delineate distinct patterns of EBV DNA presence, levels, and antibody responses across various EBV‐associated diseases. We recommend that plasma EBV DNA testing be employed as the first‐line diagnostic approach for high‐risk individuals, with subsequent PBMC EBV testing conducted for those exhibiting negative plasma results. A comprehensive evaluation of both EBV DNA and serological markers is essential for accurate identification and differential diagnosis of EBV‐related disorders.