Epstein-Barr Virus (EBV) Infection

Background

• Epstein-Barr virus (EBV) is a ubiquitous herpesvirus with a worldwide prevalence of > 90%.
• Primary infection is asymptomatic in some persons but may cause infectious mononucleosis in others.
• Following the primary infection, EBV establishes a lifelong persistent infection in the human B cell.
• Though EBV has intrinsic oncogenic potential, persistent infection is benign and well-controlled by the immune system in most healthy people.
• In other persons, persistent infection is associated with malignancies and other syndromes, such as:
  • Hodgkin lymphoma
  • Burkitt lymphoma
  • nasopharyngeal carcinoma
  • gastric carcinoma
  • multiple sclerosis
• T-cell-mediated immunity is particularly important for the control of a latent infection, and immunocompromised patients are at particular risk for developing EBV-related disorders including:
  • posttransplant lymphoproliferative disorder(PTLD)
  • oral hairy leukoplakia
  • AIDS-related lymphomas

Evaluation

• Available tests for the diagnosis of EBV-related disorders include:
  • heterophile antibody testing, a rapid assay used for the diagnosis of acute infectious mononucleosis
  • EBV serologies, a panel of 3-4 EBV-specific antibodies, used for
    • definitive diagnosis of infectious mononucleosis
    • distinguishing acute vs. prior infection or absence of infection
  • EBV viral load testing
    • quantitative polymerase chain reaction (PCR), mainly used to monitor patients at risk for the development of PTLD
    • neither approved nor reliable for the diagnosis of infectious mononucleosis
  • Epstein-Barr encoding region (EBER) in situ hybridization, used to detect presence of EBV in biopsy specimens

Management

• Several antiviral medications have in vitro activity against EBV, but none are approved for clinical use, and evidence of clinical benefit is limited.
  • Acyclovir-based drugs have been shown to reduce viral shedding, but not to consistently reduce the severity or duration of symptoms in infectious mononucleosis.
  • Oral and topical antivirals may be effective for treatment of oral hairy leukoplakia, but the evidence is derived from small studies and cases series.
• Treatment of EBV-associated malignancies is typically specific to that malignancy.
• Adoptive transfer for EBV-specific cytotoxic T lymphocytes is emerging as a promising therapeutic approach.