Infectious Mononucleosis is Associated with Hodgkins Lymphoma in Young Adults

Researchers from Denmark and Sweden have clarified the relationship between documented Epstein Barr Virus (EBV) infectious mononucleosis and EBV associated Hodgkin’s lymphoma. They concluded that young adults with serologically documented EBV infection had an increased risk of EBV associated Hodgkin’s lymphoma but not EBV negative Hodgkin’s lymphoma. These results appeared in the October 2, 2003 issue of the New England Journal of Medicine. Epstein-Barr virus is a tumorigenic herpes virus that is ubiquitous in the adult population, occurring in 90% of the general population world wide. The virus is generally spread among young children through salivary contact, and only causes clinical illness when primary infection is delayed until adolescence or beyond. Symptomatic infectious mononucleosis occurs in approximately 50% of young adult cases of EBV infection. Epstein-Barr virus is a life-long, latent infection of B lymphocytes which influences B-cell survival mechanisms. Epstein-Barr virus may induce tumors such as B-lymphoproliferative disease and Hodgkin's disease. It has been known for some time that young adults with infectious monocucleosis were at increased risk for the development of Hodgkin’s lymphoma. This risk has been estimated to be approximately one case of Hodgkin’s lymphoma per 1000 individuals with infectious mononucleosis. However, it is unknown if there is truly a causal relationship between EBV virus infection and Hodgkin’s lymphoma. These authors compared the incidence rates of Hodgkin’s lymphoma in a cohort of over 17,000 patients with serologic evidence of infectious mononucleosis to a cohort of over 24,000 individuals without evidence of infectious mononucleosis. They used molecular techniques to determine the presence of EBV virus in biopsy specimens of those with Hodgkin’s lymphoma. The researchers reported that “Only serologically confirmed infectious mononucleosis was associated with a persistently increased risk of Hodgkin’s lymphoma.” This increased incidence (relative risk = 4.0) was related only to EBV positive and not EBV negative Hodgkin’s lymphoma. “The estimated median incubation time from mononucleosis to EBV-positive Hodgkin’s lymphoma was 4.1 years.”