Factors influencing CMV seropositivity in stem cell transplant patients and donors

Patient MV serological status remains an important factor for the outcome of allogeneic stem cell transplantation (SCT). CMV seronegative patients receiving a graft from a seronegative donor have lower transplant-related mortality. In a previous study using the EBMT registry, we found that CMV seropositive patients receiving grafts from seropositive unrelated donors had improved survival and reduced transplant-related mortality compared to those receiving grafts from CMV seronegative donors. Similar results were found in a single centre study by Ringdén et al. However, two other large studies have not been able to show any positive effect from using a CMV seropositive donor. Many different factors influence the risk of being CMV seropositive. The probability varies between different countries. One study suggests that the risk has been reduced in recent years. We used the registry of the European Group for Blood and Marrow Transplantation (EBMT) to look for trends over time regarding CMV serostatus and analyze the effects of age, gender and country.