Risk Factors and Utility of a Risk-Based Algorithm for Monitoring Cytomegalovirus, Epstein-Barr Virus, and Adenovirus Infections in Pediatric Recipients after Allogeneic Hematopoietic Cell Transplantation

• Pretransplantation viremia, cytomegalovirus risk status, and use of alemtuzumab are associated with post–allogeneic hematopoietic cell transplantation viremia
• Cytomegalovirus risk status, viremia, and viral disease result in higher health care utilization
• The algorithm developed from our data can potentially reduce viral PCR testing by 50%
• Preventative treatment strategies for children at risk of post–allogeneic hematopoietic cell transplantation viremia are needed

Infectious complications, particularly viral infections, remain a significant cause of morbidity and mortality after allogeneic hematopoietic cell transplantation (alloHCT). Only a handful of studies in children have analyzed the risks for and impact of viremia on alloHCT-related outcomes. We conducted a retrospective study of 140 pediatric patients undergoing alloHCT to investigate the incidence of and risk factors for cytomegalovirus (CMV), adenovirus (ADV), and Epstein-Barr virus (EBV) viremia and viral disease after alloHCT. Furthermore, we assessed the impact of viremia on days of hospitalization and develop an algorithm for routine monitoring of viremia. Patients were monitored before alloHCT and then weekly for 180 days after alloHCT. Patients were considered to have viremia if CMV were > 600 copies/mL, EBV were > 1000 copies/mL, or ADV were > 1000 copies/mL on 2 consecutive PCRs. The overall incidences of viremia and viral disease in all patients from day 0 to +180 after alloHCT were 41.4% (n = 58) and 17% (n = 24), respectively. The overall survival for patients with viremia and viral disease was significantly lower compared with those without viremia (58% versus 74.2%, P = .03) and viral disease (48.2% versus 71.2%, P = .024). We identified that pretransplantation CMV risk status, pre-alloHCT viremia, and use of alemtuzumab were associated with the risk of post-alloHCT viremia. The average hospitalization days in patients with CMV risk (P = .011), viremia (P = .024), and viral disease (P = .002) were significantly higher. The algorithm developed from our data can potentially reduce viral PCR testing by 50% and is being studied prospectively at our center. Improved preventative treatment strategies for children at risk of viremia after alloHCT are needed.