EPSTEIN-BARR VIRUS IN ORGAN TRANSPLANT RECIPIENTS
Epstein-Barr virus or EBV is a member of the herpesvirus family of viruses, just like CMV. It is very common and approximately 50 % of children by age 5 and about 90 % of adults have been infected with this virus.
In children, there are usually no symptoms after infection. In adolescents and young adults, EBV causes infectious mononucleosis or “mono”. Just like the other members of this virus family, EBV can be spread via bodily fluids such as saliva, blood and semen.
This virus usually lies dormant in the body and can get “re-activated” when the body’s immune system is weakened, usually after an organ transplant or with AIDS. New infections can also be transmitted via the transplanted organ in a recipient who previously did not have EBV infection.
The most dangerous consequence of EBV infection after organ transplantation is PTLD or post-transplant lymphoproliferative disorder. It is estimated that 70 % of PTLD is caused by EBV. This complication can range from having a benign growth of B cells to non-Hodgkin’s lymphoma, a form of blood cancer that needs to be treated aggressively and has a poor prognosis.
Currently, there are no vaccines that can prevent EBV. Antiviral drugs cannot prevent re-activation of the virus either. Therefore, treatment will depend on the serostatus of the patient and if the patient has PTLD. Serostatus is the presence or absence of EBV in the body. Seropositive status means that the person has been infected with EBV and has certain proteins known as antibodies in his blood. Seronegative status means that the person has not been infected with EBV and does not have the antibodies in the blood. Some transplant centers advocate using anti-viral medications to decrease the viral load in patients who are seronegative who receive organs from seropositive donors.
Treatment for PTLD involves reducing the immunosuppression drugs so that the body’s immune system could fight off the virus. If this is not effective, further treatment with a drug called rituximab or even more aggressive treatment with chemotherapy is undertaken.