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

University Laboratory (ISO: 15189:2012) for microbiological analysis. Viral nucleic acids were extracted from the NPA with a MagAttract Virus Mini M48 kit (Qiagen, Sollentuna, Sweden) and analyzed with in-house real-time PCRs for the following 16 viruses: adenovirus (HAdV); bocavirus (HBoV); coronaviruses NL63/OC43/229E/HKU1 (HCoV); enterovirus (EV); influenza virus A, including A(H1N1)pdm09 and B (Flu); metapneumovirus (HMPV); parainfluenza viruses 1-3 (PIV); respiratory syncytial virus (RSV) and rhinovirus (RV) [19] . A semiquantitative assay was used and the actual Cycle thresholds-values (Ct-values) were provided, however, the NPA has not been validated for quantitative data. In all study subjects who initially tested positive for one or more respiratory viruses, a follow-up sample was collected at the time of their next visit to the hospital. This follow-up sample was collected regardless of the patient's absolute neutrophil count or symptoms and was analyzed in the same manner as the first sample. However, if the patient had a new episode of febrile neutropenia at the time of the follow-up, this sample was considered both a follow-up sample and a new episode sample, which required an additional follow-up sample if the new episode tested positive for a respiratory virus.