Background

Due to clinical reasons, in stem cell transplant setting viral infections are divided as latent (herpesviruses, BKV) and sporadic (adenovirus – ADV, rotavirus – RV, influenza – INFL and others).

Objective

The aim of this study was the analysis of incidence and outcome of viral infections in 5 Polish pediatric hematopoietic stem cell transplantation (HSCT) centers.

Patients and methods

A total number of 308 HSCTs (allo – 232, auto – 76) performed over a period of 24 months in children and adolescents in participating centers were analyzed retrospectively.

Results

In the period under analysis, 205 viral infections were diagnosed (197 after allo-HSCT, and 8 after auto-HSCT). After allo-HSCT, infections occurred in 119 (51.3%) patients, of which 51.2% were one of multiple infections: 58 patients were infected with one virus, 29 with two, 16 with three and 16 with four or more viruses. Cumulative incidence of viral infections after allo-HSCT was: CMV – 28.0%, BKV – 18.5%, EBV – 15.5%, ADV – 9.5%, RV – 9.1%, VZV – 2.6%, INFL – 0.9%, HHV6 – 0.9%. In 8 (10.5%) auto-HSCT patients following infections were diagnosed: RV – 4, CMV – 2, ADV – 1, BKV – 1. With respect to specific virus, there were no differences between patients’ age and time from HSCT to beginning of infection (medians: 0.8–2.4 month), except for late VZV infection occurring at median time of 6.5 month after HSCT. Cure rates were lowest for: EBV (90,7%), ADV (93,8%), BKV (94,2%), CMV (94,6%), and reached 100% in case of INFL, HBV, VZV, HHV6 and RV.

Conclusions

Viral infections in children after HSCT occur in over 50% of the patients after allo-HSCT and 10% after auto-HSCT. Mixed and multiple infections occur frequently. Infections with CMV, EBV, BKV or ADV contribute to deaths in 5–10% patients.