[Diagnosis and management of EBV-positive lymphoproliferative disorders].

Epstein-Barr virus (EBV) has the ability to immortalize not only B cells but also T and natural killer (NK) cells. The virus may also contribute to the onset of EBV-positive lymphoproliferative disorders (EBV-LPDs) by inducing the introduction of gene mutations. It is known that B cell EBV-LPDs (B-EBV-LPDs) develop with preexisting immunodeficiency, but the onset mechanism of T cell and NK cell EBV-LPDs (T-EBV-LPDs and NK-EBV-LPDs), also known as chronic active EBV disease and associated diseases, is unclear. The diagnosis of both EBV-LPDs requires the quantitative examination of EBV-DNA in the peripheral blood. Eliminating the cause of immunodeficiency or administering rituximab is effective in treating B-EBV-LPDs, but some B-EBV-LPDs and T-EBV-LPDs/NK-EBV-LPDs are resistant to pharmacotherapy. Therefore, further research is needed to explicate the pathophysiology of EBV-LPDs and develop a drug for its treatment.