High incidence of pulmonary bacterial co-infection in children with severe respiratory syncytial virus (RSV) bronchiolitis

Abstract

Background: Respiratory syncytial virus (RSV) is the most common cause of viral lower respiratory tract infections (LRTI). Viral LRTI is a risk factor for bacterial superinfection, having an escalating incidence with increasing severity of respiratory illness. A study was undertaken to determine the incidence of pulmonary bacterial co-infection in infants and children with severe RSV bronchiolitis, using paediatric intensive care unit (PICU) admission as a surrogate marker of severity, and to study the impact of the co-infection on morbidity and mortality. Methods: A prospective microbiological analysis was made of lower airways secretions on all RSV positive bronchiolitis patients on admission to the PICU during three consecutive RSV seasons. Results: One hundred and sixty five children (median age 1.6 months, IQR 0.5-4.6) admitted to the PICU with RSV bronchiolitis were enrolled in the study. Seventy (42.4%) had lower airway secretions positive for bacteria: 36 (21.8%) were co-infected and 34 (20.6%) had low bacterial growth/possible co-infection. All were mechanically ventilated (median 5.0 days, IQR 3.0-7.3). Those with bacterial co-infection required ventilatory support for longer than those with only RSV (p,0.01). White cell count, neutrophil count, and C-reactive protein did not differentiate between the groups. Seventy four children (45%) received antibiotics prior to intubation. Sex, co-morbidity, origin, prior antibiotics, time on preceding antibiotics, admission oxygen, and ventilation index were not predictive of positive bacterial cultures. There were 12 deaths (6.6%), five of which were related to RSV. Conclusions: Up to 40% of children with severe RSV bronchiolitis requiring admission to the PICU were infected with bacteria in their lower airways and were at increased risk for bacterial pneumonia.

Lung disease in indigenous children

“…27 While this may be a diagnostic error, it is also biologically plausible. Concurrent bacterial infection are more common in those with severe bronchiolitis, 31 and bacteria pneumonia rates may be truly higher for several reasons including the aspiration of nasal secretions which, in these children, contains large bacterial load. 32 This potentially overwhelms the local lung defences (mucosal and innate immunity) already impaired by the viral infection.…”

CT-Morphological Characterization of Respiratory Syncytial Virus (RSV) Pneumonia in Immune-Compromised Adults

“…However, not every patient underwent BAL and not every pathogenic agent detected via BAL causes pneumonia but in some cases only colonization without a pathogenic effect [20,24,25]. For example, an RSV infection of the respiratory tract was detected in a prospective study including 165 children on ventilation (median age 1.6 months old), 22 % of whom had a verified bacterial co-infection and another 21 % had a possible bacterial co-infection [19]. Fourthly, no special or systematic examination of the paranasal sinuses (e. g. nasopharyngeal lavage, nasal swab) was performed in patients with sinusitis since this issue was not the focus of the head examinations [23].…”

Respiratory syncytial virus infection in children admitted to hospital but ventilated mechanically for other reasons

“…The reported incidence of bacterial coinfections in intensive care patients with RSV infection varies highly depending on the methods used and (sub) populations observed (1-46%) [Hall et al, 1988;Korppi et al, 1989]. Thorburn et al [2006] reported the clinical course of 165 children with severe RSV bronchiolitis (all admitted to the pediatric intensive care unit and mechanically ventilated). In 42% of cases, lower airway specimens yielded bacterial growth.…”