Viral infections in children undergoing hematopoietic stem cell transplant

Background Although viral infection is a major clinical problem for hematopoietic stem cell transplant recipients, there are few large series reporting on these infections in the pediatric population. We performed a retrospective analysis of the impact of viral infections in this patient population in our center, managed by a uniform antiviral prophylaxis protocol. Method We reviewed the medical records of consecutive children and adolescents who received hematopoietic stem cell transplantation at the Division of Pediatrics, The University of Texas M. D. Anderson Cancer Center in Houston, TX, from July, 1992 to August, 1996. Results. During the study period there were 70 episodes of viral infections in 96 transplants. The viruses most commonly encountered were cytomegalovirus (24), varicella-zoster (21) and herpes simplex (10). Fifty of these episodes resulted in clinically apparent diseases, affecting 39 patients. The Kaplan-Meier estimated probability for the development of viral diseases was 62%. Ten percent of these patients died as a direct result of the infectious process, all within 4 months of transplant. Significant factors for development of viral disease were the development of acute graft-vs. -host disease and the duration of preengraftment neutropenia. Conclusions. Viruses are common pathogens after hematopoietic stem cell transplantation in the pediatric population. Despite routine antiviral prophylaxis the morbidity and mortality of viral infections remain high. Enhancement of immune recovery after hematopoietic stem cell transplantation together with the development of new classes of antiviral agents may impact the incidence and prognosis of viral infections in this setting.