Prevalence of rhinovirus in wheezing children: a comparison with respiratory syncytial virus wheezing

Abstract Objective To explore the distribution and clinical manifestations of rhinovirus infection in wheezing children, and compare the clinical differences between rhinovirus- and respiratory syncytial virus-induced wheezing. Materials and methods This prospective cohort study was carried out in Children's Hospital of Soochow University from Dec 2012 to Nov 2014. We enrolled consecutive hospitalized children <60 months of age presented with wheezing. Clinical data including cough, fever, dyspnea, crackles were recorded by pediatricians on the first day of admission. Meanwhile, nasopharyngeal aspirates were obtained to test for respiratory viruses, by using polymerase chain reaction method for rhinovirus, human bocavirus, and human metapneumovirus, and direct immunofluorescence assay to test for respiratory syncytial virus, adenovirus, parainfluenza virus types 1–3, and influenza virus types A and B. Results Rhinovirus was a main causative agent isolated in 14.7% of the hospitalized wheezing children in Suzhou, China, being second to respiratory syncytial virus (21.0%). Different from respiratory syncytial virus infection, which peaked in winter months, rhinovirus could be detected all year round, peaked between July and September, and in November. Children with rhinovirus infection were older and presented with more often allergic sensitizations, blood eosinophilia, and leukocytosis than those of respiratory syncytial virus infection. Logistic regression analysis revealed that rhinovirus-infected children experienced earlier wheezing more often than respiratory syncytial virus children (odds ratio, 3.441; 95% confidence interval, 1.187–9.979; p = 0.023). Conclusion Rhinovirus was a main viral pathogen in wheezing children, especially in summer time. Rhinovirus-induced wheezing was different from respiratory syncytial virus, apart from seasonal epidemics; these two groups differed with regard to age, allergic sensitizations, laboratory test, and history of wheezing episodes.

Comparison of severe pneumonia caused by Human metapneumovirus and respiratory syncytial virus in hospitalized children.

Objectives: The objective of this study is to compare the incidence and clinical characteristics of severe pneumonia caused by Human metapneumovirus (hMPV) to respiratory syncytial virus (RSV) infection in children. Patients and Methods: A total of 151 children hospitalized with severe pneumonia, were tested for hMPV using reverse-transcription polymerase chain reaction. At the same time, samples were tested for RSV and other common respiratory viruses. Medical records, including clinical, laboratory data, and chest radiography findings, were reviewed for all children. Results: Of the 151 samples, 88 (58.3%) were positive for respiratory viruses. Of the 88 positive, there were 6 (4.0%) with hMPV, 66 (43.7%) with RSV, 13 (8.6%) with influenza A, 2 (1.3%) with parainfluenza virus III, 1 (0.7%) with parainfluenza virus I, 1 (0.7%) with adenovirus and 1 (0.7%) with influenza B. hMPV-infected patients were significantly older than RSV-infected patients (P < 0.001). Children with hMPV pneumonia had fever more frequently (P = 0.03). Two hMPV-positive patients (33.3%) required admission to an intensive care unit, and two patients (33.3%) required mechanical ventilation. The duration of illness was 18.33 ± 7.09 days. These characteristics of hMPV infections were similar to patients with RSV infections. Conclusion: Human metapneumovirus is an infrequent viral pathogen causing severe pneumonia in children. Children with hMPV were older than those with RSV. The disease caused by hMPV was similar in presentation and severity to RSV, with a minority of children requiring additional respiratory support.

Clinical significance of different bacterial load of Mycoplasma pneumoniae in patients with Mycoplasma pneumoniae pneumonia

OBJECTIVE: This retrospective study was conducted to investigate the clinical significance of differentMycoplasma pneumoniae bacterial load in patients with M. pneumoniae pneumonia (MP) in children. METHODS: Patients with MP (n=511) were identified at the Children's Hospital Affiliated to Soochow University database during an outbreak of MP between January 2012 and February 2013. RESULTS: Comparing patients with high and low bacterial load those with higher loads were significantly older (p<0.01) and had fever significantly more frequently (p=0.01). Presence of wheezing at presentation was associated with low bacterial load (p=0.03). Baseline positive IgM was present in 93 (56.4%) patients with high bacterial load compared to 46 (27.8%) patients with low bacterial load (p<0.001). Co-infection with viruses was found significantly more frequent among patients with low bacterial load (24.2%) than those with high bacterial load (8.5%) [p<0.001]. Bacterial co-infection was also more frequently detected among patients with low bacterial load (22.4%) than in those with high bacterial load (12.1%) [p=0.01]. CONCLUSION: M. pneumoniae at a high bacterial load could be an etiologic agent of respiratory tract disease, whereas the etiologic role of MP at a low bacterial load remains to be determined. .