ABSTRACT
BACKGROUND: Epstein-Barr virus is considered a risk factor for the development of multiple sclerosis, and recent findings reveal infected plasma -cells in meningeal ectopic lymphoid deposits. Activation of the dormant virus could be responsible for the multiple sclerosis exacerbation AIMS: To compare Epstein-Barr nuclear IgG (EBNA IgG) titer in newly diagnosed treatment-naive multiple sclerosis patients regarding the diagnoses date, clinical and radiological activity. METHODS: Treatment-naive multiple sclerosis patients were divided into two groups according to Poser (late group) and McDonald2017(early group) diagnostic criteria. EBNA IgG, EDSS, physical (Timed 25 Foot Walk test, Nine-hole Peg test), and cognitive tests (Brief International Cognitive Assessment for Multiple Sclerosis) were done before the methylprednisolone infusion. The lesion location was evaluated by an MRI. Myelitis was considered a severe attack, and optic neuritis a mild relapse. RESULTS: In total, 69 patients were enrolled. 44 (63.8%) of them were diagnosed by McDonald2017, and 25 (36.2%) were diagnosed with Poser criteria. There was a significant difference (p = 0.049) between the EBNA IgG titer of the late (median:238 U/ml, IQR: 154-362) and early (median: 154 U/ml, IQR:100.25-293.25). Severe relapse, having a spinal cord lesion, and not being treated with methylprednisolone was associated with higher EBNA IgG titer. CONCLUSION: Study results show that EBNA IgG was significantly associated with disease activity regarding relapse severity and lesion location and could be a potential biomarker for predicting disease exacerbation.