Multiple viral infections post-hematopoietic stem cell transplantation are linked to the appearance of chronic GVHD among pediatric recipients of allogeneic grafts

Delayed immune reconstitution and the ensuing opportunistic infections among children following hematopoietic stem cell transplantation (HSCT) are associated with increased treatment-related morbidity and mortality (TRM). We retrospectively evaluated the impact of viral infections on the posttransplant recovery of pediatric recipients of stem cell grafts as a reflection of their posttransplant immunoreconstitution in a single institution setting. The case histories of 124 children (during 1/1999-9/2006) were reviewed for infectious episodes, and correlated with their respective clinical parameters. Patients with a high risk for CMV received prophylaxis, but failures in the prophylaxis were common (40%). 110/124 (89%) of these allogeneic patients had at least one viral reactivation/clinical infection posttransplant. In this group of pediatric patients chronic GVHD (P < 0,001) and secondary graft failure were significantly (P=0,001) associated with early (during the first 100 days post HSCT), multiple (>= 2) viral infections. Our data indicate that viruses are common pathogens among pediatric recipients of allogeneic stem cell grafts. In this group of patients multiple viral infections early on seem to reflect an even more severe degree of immunological derangement in the recipient and identify a group of patients with an increased risk of chronic GVHD and secondary graft failure.