Risk Factors for Cytomegalovirus Infection After Allogeneic Hematopoietic Cell Transplantation in Malignancies: Proposal for Classification

To identify and classify risk factors for cytomegalovirus (CMV) infection and disease in patients receiving allogeneic hematopoietic stem cell transplantation (allo-HSCT), treated mainly for acute leukemia.

A literature search was performed;eligible trials were clinical studies assessing the risk factors for CMV infection or disease in multivariate analysis.

Early reactivation in the setting of allo-HSCT took place mainly in patients without CMV prophylaxis, while late reactivation mainly in those patients who had completed previous prophylaxis or were on anti-CMV strategy based on pre-emptive prophylaxis. We propose classifying risk factors for CMV reactivation and CMV disease in patients after allo-HSCT as major and minor ones. Three major risk factors for CMV reactivation and CMV disease were found: (i) CMV-negative donor CMV-positive recipient serostatus, (ii) acute or chronic graft-versus-host disease, and (iii) unrelated or mismatched donor.

CMV reactivation should be regarded as a continuous function of recipient and donor CMV-seropositivity and recipient immune suppression, caused by conditioning, immunosuppressive therapy and human leukocyte antigen disparity between donor and recipient.