Background: In a substantial proportion of respiratory tract diseases of suspected infectious origin, the etiology is unknown. Some of these cases may be caused by the recently described human bocavirus (hBoV). The aim of this study was to investigate the frequency and the potential clinical relevance of hBoV in pediatric patients.

The human bocavirus (hBoV) was first described in 2005 in respiratory tract samples. The clinical relevance of hBoV is still unclear. The aim of our study was to establish a real-time PCR assay for the detection and quantification of hBoV DNA, to apply the real-time assay for the analysis of stool and serum samples for the presence of hBoV DNA, and to perform a phylogenetic analysis of the hBoV positive samples. A total of 834 nasopharyngeal aspirates (NPA), 10 serum samples, and 31 stool samples of children with acute respiratory diseases were retrospectively tested. For phylogenetic analysis, 968 bp of the VP2 gene were sequenced from 69 hBoV-positive NPA samples. The qualitative results of the real-time hBoV PCR were in good agreement with a conventional hBoV PCR. We found that 12% of the NPA were positive for hBoV DNA. The median viral load in the NPA was 4.9 ؋ 10 3 copies/ml (range, 2.7 ؋ 10 0 to 1.5 ؋ 10 11 copies/ml). There was no difference of the hBoV load in NPA between children with or without known coinfection, but the load was significantly higher in children with bronchitis than in children with the diagnosis of febrile seizures. hBoV DNA was found in 1 of 10 serum samples and in 14 of 31 stool samples. hBoV sequence identity was >99% in the VP2 region. In conclusion, hBoV DNA can be found in NPA samples at very high titers. In addition to being found in the respiratory tract, hBoV was found in stool samples. The clinical relevance of these findings remains to be determined.

Increasing evidence suggests that the recently identified human bocavirus (hBoV) is a cause of acute respiratory illness. However, the duration of hBoV shedding from the respiratory tract as demonstrated by positive hBoV polymerase chain reaction is unclear. We describe the virologic and clinical characteristics of 6 immunocompetent children with hBoV persistence in the respiratory tract for up to 4.5 months.

Background: Cystic fibrosis (CF) lung disease starts in the first months of life often before the onset of clinical symptoms. Multiple breath washout (MBW) detects abnormal lung function in infants and young children in the laboratory setting. Objective: The aim of this study was to determine the feasibility of MBW in 0- to 4-year-old children with CF and non-CF controls in the clinical setting. Methods: Fourteen children with CF (mean age 1.3 ± 1.0 years) and 26 age-matched non-CF controls were sedated with chloral hydrate and MBW was performed with sulfur hexafluoride. Results: MBW measurements were successful in 27 of 40 children (67.5%). The mean lung clearance index (LCI) was significantly higher in CF patients compared to non-CF controls (p = 0.006). Further, the frequency of elevated LCI (z-score >1.96) was significantly increased in CF patients compared to controls (p = 0.0003). Conclusions: We conclude that MBW is feasible and sensitive to detect abnormal lung function in infants and young children with CF in the clinical setting.