Advances in CMV infection prevention and treatment after allo-HSCT

Cytomegalovirus (CMV) remains a major cause of morbidity and mortality in allogeneic hematopoietic stem cell transplant (HSCT) recipients. Despite this knowledge, a number of CMV-related diagnostic and therapeutic issues remain critical. No uniform guidance exists for the best strategy to monitor and prevent CMV infection and disease. In particular, we lack standard threshold values for assessing the CMV DNAemia in the monitoring of CMV infection; there is no consensus in the adoption of immunoglobulin therapy and adoptive transfer of HSCT donor-derived CMV-specific T cells. Furthermore, antiviral drugs used in the preemptive therapy are characterized by high levels of toxicity. Of interest, recent availability of new drugs will probably modify the antiviral strategy in a large proportion of patients. The uncertainty in the management of CMV infections is further complicated by the continuous evolution in the transplantation strategies and the consequent infectious risk. This paper will focus on challenging issues in the monitoring, prevention, and treatment of CMV infections in allo-HSCT populations. Assessment of pretransplant CMV status, immunological monitoring after transplant, and CMV disease prevention and therapy strategies will be discussed.