Prevention of Transfusion-Transmitted Cytomegalovirus Infections: Which is the Optimal Strategy?

Abstract

Traditionally, leukoreduction and selection of blood products from seronegative donors have been used as alternative strategies to reduce the risk of transfusion-transmitted cytomegalovirus infections (TT-CMV) in atrisk patients. After the introduction of universal leukoreduction for red blood cell and platelet concentrates in Germany, a controversy evolved as to whether the additional selection of blood products from seronegative donors would reduce or even increase the risk of TT-CMV. This review summarizes the current knowledge about CMV infections in blood donors and the implications of this information on the effect of potential transfusion strategies. Even though there are conflicting data about the incidence of TT-CMV remaining after the introduction of leukodepletion, it has been clearly shown that both prevalence and concentration of CMV DNA in peripheral blood are highest in newly seropositive donors. Therefore, avoidance of blood products from these donors is the most important goal of any transfusion strategy. This goal can be reached by: i) selection of blood products from seronegative donors, ii) provision of CMV DNA-negative blood products, or iii) provision of blood from long-term seropositive donors. In cases of suspected TT-CMV, all implicated donors should be investigated carefully to gather further knowledge on which donors confer the lowest risk for TT-CMV.

Cytomegalovirus Immunoglobulin G Avidity Index among Blood Donors in Alexandria, Egypt

“…In many developed countries, it is not mandatory to screen donated blood for CMV in blood banks (8,11). That is why Kothari et al suggested that the estimation of the seroprevalence among voluntary blood donors may be of help to decide whether screening for CMV would eliminate transmission of infection to high-risk groups (29).…”

“…Vulnerable groups to serious illness caused by this virus are immunocompromised hosts, neonates and pregnant women (5,6). Exclusion of seropositive blood units and leucodepletion are the two main strategies to minimize CMV transmission to high risk recipients (11).…”

“…The established link between primary CMV infection during pregnancy and congenital infection makes identification of pri-mary CMV infection an important goal in maternal and neonatal health care (13). Applying this concept to donated blood -safe blood for transfusion would be that without evidence of primary CMV infection (11).…”

Current strategies and future directions for the prevention of transfusion-transmitted cytomegalovirus

“…42,46 This potential risk has led to proposals that LR-only blood products be collected from donors who have been seropositive for at least 1 year or that the donors also be screened for CMV by PCR. 34,45,47 However, it remains to be determined whether the latter would be a cost-effective way to further decrease the risk of TT-CMV infection. For example, a recent study detected CMV DNA in the plasma of only 0.03% of blood donors.…”

Humanes Cytomegalievirus (HCMV)

“…Beim derzeitigen Wissenstand ist keine Präferenz für eine Methode sicher belegbar [135]. Nach Verfügbarkeit des WHO-Standards für HCMV-DNA, kommerzieller Assays und Ringversuche ist eine höhere Standardisierbarkeit und Vergleichbarkeit der NAT-Methoden gegeben [136][137][138].…”