Adenovirus Infections in Hematologic Malignancy and Hematopoietic Cell Transplant Recipients: Epidemiology,...

Human adenovirus (HAdV) infection represents a significant cause of morbidity and mortality in patients with hematologic malignancies, particularly following allogeneic hematopoietic stem cell transplant. Clinical manifestations range from asymptomatic DNAemia to pneumonitis, enterocolitis, hepatitis, hemorrhagic cystitis, myocarditis, and central nervous system disease. Advances in molecular diagnostics, including quantitative polymerase chain reaction, have enabled earlier detection and surveillance, yet interpretation remains challenging given the absence of standardized viral load thresholds and international quantitative standards. Reported incidence varies by age, transplant type, geographic regions, and surveillance strategy, with pediatric recipients demonstrating higher infection rates, while mortality among patients with DNAemia or disseminated disease remains substantial. Risk factors include T-cell depletion, cord blood transplant, severe graft-versus-host disease, high-dose corticosteroid exposure, and delayed immune reconstitution. Management relies primarily on immune recovery and reduction of immunosuppression when feasible. Intravenous cidofovir remains the most widely used antiviral despite nephrotoxicity, while intravenous brincidofovir represents a potentially promising emerging approach. The impact of contemporary transplant approaches, including post-transplant cyclophosphamide and novel cellular therapies, on HAdV epidemiology requires further study. This review summarizes contemporary epidemiology, definitions, diagnostic strategies, and evolving therapeutic options for HAdV infection in patients with hematologic malignancies, highlighting ongoing challenges.