Prevalence and Activity of Epstein-Barr Virus and Human Cytomegalovirus in Symptomatic and Asymptomatic Apical Periodontitis Lesions

IntroductionApical periodontitis is a polymicrobial inflammation with a dominant flora of opportunistic Gram-negative bacteria; however, a pathogenic role of human herpesviruses such as Epstein-Barr virus (EBV) and human cytomegalovirus (HCMV) has been implicated recently. The aims of this study were to determine the prevalence, activity, and disease association of EBV and HCMV in apical periodontitis in an Eastern Hungarian population.MethodsForty samples with apical periodontitis (17 symptomatic and 23 asymptomatic) and 40 healthy pulp controls were collected. EBV and HCMV prevalences were measured by polymerase chain reaction (PCR) detection of the viral DNA and viral activity was tested by reverse-transcription PCR amplification of viral messenger RNA.ResultsEBV DNA and EBNA-2 messenger RNA were found in apical periodontitis lesions at significantly (p < 0.0001) higher frequencies (72.5% and 50%, respectively) than in controls (both 2.5%). The occurrence of HCMV infection was rare in both apical lesions (10%) and controls (0%). The presence of EBV DNA in apical lesions was associated significantly with large (≥5 mm) lesion size (p = 0.02) but not with symtoms (p = 0.30). Symptomatic manifestation was significantly associated with the co-occurrence (odds ratio [OR], 8.80; 95% confidence interval [CI], 1.69-45.76) but not the sole occurrences of EBNA-2 messenger RNA (OR, 2.29; 95% CI, 0.48-11.06) and large lesion size (OR, 4.02; 95% CI, 0.81-19.89).ConclusionEBV infection is a frequent event in apical periodontitis, whereas the involvement of HCMV still remains to be elucidated. This study showed that symptomatic manifestation was likely to occur if a large-sized apical periodontitis lesion is aggravated with active EBV infection.