Frequent Respiratory Viral Infections in Children with Febrile Neutropenia - A Prospective Follow-Up Study

Söderman, Martina; Rhedin, Samuel; Tolfvenstam, Thomas; Rotzén-Östlund, Maria; Albert, Jan; Broliden, Kristina; Lindblom, Anna

It is crucial to correctly diagnose febrile neutropenia in immunosuppressed children, as infections with viruses [23, 24] , bacteria [25, 26] or fungi can be fatal [26] in this group of patients. The clinical significance of a single time-point PCR finding of certain pathogens has been debated. Studies on immunocompetent children have reported that viruses such as HBoV, HCoV, and RV are detected in asymptomatic children at rates ranging between 27-40% [13] [14] [15] [16] , which could be suggestive of prolonged viral shedding from an earlier infection or the incubation period prior to a symptomatic- [17] , or asymptomatic infection [13, 14, 17] . To clarify this issue, more longitudinal studies with appropriate control groups are needed. Rhedin et al. conducted a case-control study to investigate the etiologic role of respiratory viruses in a group of children with respiratory tract symptoms seeking medical care at a pediatric emergency center [13] . The control group consisted of children on routine visits to child welfare centers for vaccination within the childhood immunization program. The detection rate of respiratory viruses in the control group was high (35.4%) with RV and HCoV the most commonly detected viruses in asymptomatic children and HMPV, PIV and RSV detected only rarely. The authors concluded that HMPV, PIV and RSV play an etiologic role and suggested that findings of RV and HCoV must be carefully interpreted [13] .We chose a longitudinal design for the present study, and found that 78% of the infections had resolved by the median follow-up time of 28 days. In addition, two of the RV infections identified at follow-up represented new species of RV from the previous infection, which increases the proportion of resolved infections to 84%.