Qualitative and Quantitative Molecular Analysis of Epstein-Barr Virus in Iraqi Patients with Relapsing-Remitting Multiple Sclerosis

Abstract

Multiple sclerosis (MS) is a neuro-inflammatory disorder in which the Epstein-Barr virus (EBV) is proposed to have a pathogenic role. Therefore, a case-controlstudy was performed (93 patients with relapsing-remitting MS and 113 healthycontrols (HC) to analyze the prevalence and viral load of EBV infection using realtime-polymerase chain reaction. Prevalence of EBV infection was lower in patientscompared to HC but the difference was not significant (12.9 vs. 21.2%; probability[p] = 0.187). EBV-positive MS cases were more common in females than in males(83.3 vs. 16.7%), while an opposite distribution was observed in HC (37.5 vs.62.5%), and the difference was significant (p = 0.041). Blood group O frequencywas higher in EBV-positive patients compared to the corresponding HC but thedifference was not significant (33.3 vs. 20.8%; p = 0.443). EBV-positive MS casesshowed similar frequency in the two groups of the expanded disability status scale(EDSS: < 3.0 and ≥ 3.0; 50% each). EBV load was significantly elevated in EBVpositiveMS cases compared to EBV-positive HC (94.6 ± 84.2 vs. 17.0 ± 16.3 DNAcopy/100 cells; p = 0.009). When EBV-positive MS cases were classified by gender,EDSS groups or ABO blood groups, there were no significant differences betweenEBV loads in each stratum. However, a significant correlation between EBV loadand EDSS was found (correlation coefficient = 0.620; p = 0.031). In conclusion, theprevalence of EBV infection showed no significant differences between MS patientsand HC, while EBV load was significantly higher in patients.