Assessment of disseminated adenovirus infections using quantitative plasma PCR in adult allogeneic stem cell transplant recipients receiving reduced intensity or myeloablative conditioning.

Objectives: Disseminated adenovirus (AdV) infections following allogeneic stem cell transplantation (allo-SCT) are increasingly recognised, particularly in children. This study evaluated the clinical relevance of disseminated AdV infections in adult allo-SCT recipients, after different conditioning regimens.

Methods: In a cohort of 107 adult allo-SCT recipients, receiving either reduced intensity conditioning (RIC, n = 48) or myeloablative conditioning (MAC, n = 59), AdV DNA levels in plasma were determined retrospectively at 1, 3 and 6 months following transplantation. Results of this screening regimen were compared with a cohort of 58 paediatric allo-SCT recipients, in whom AdV DNA load was monitored prospectively, as part of a pre-emptive treatment strategy. In positive cases, the course of AdV DNA load and clinical outcome were assessed.

Results: AdV DNA levels > or =1000 copies/mL were detected in five adults (4.7%) and eight children (13.8%). Screening for AdV viraemia at 1, 3 and 6 months would have detected seven of eight paediatric patients. One adult, receiving MAC, died with disseminated AdV disease and in four (three RIC and one MAC) AdV viraemia was transient without clinical symptoms specifically attributable to AdV. Seven paediatric patients with AdV viraemia were pre-emptively treated with ribavirin or cidofovir and in three of them disseminated AdV infection was related to a fatal outcome.

Conclusions: Disseminated AdV infections following allo-SCT was a rare event in the adults and cause morbidity in a minority of these patients. In four of five adult patients, spontaneous clearance of AdV viraemia occurred. Results did not differ between the conditioning regimens that were applied in the adult cohort.