Acute Bronchiolitis (acute + bronchiolitis)

Distribution by Scientific Domains


Selected Abstracts


Matrix metalloproteinase-9 and tissue inhibitor of matrix metalloproteinase-1 in the respiratory tracts of human infants following paramyxovirus infection

JOURNAL OF MEDICAL VIROLOGY, Issue 4 2007
Matthew B. Elliott
Abstract Respiratory syncytial (RSV) and parainfluenza (PIV) viruses are primary causes of acute bronchiolitis and wheezing illnesses in infants and young children. To further understand inflammation in the airways following infection, we tested for the presence of matrix metalloproteinases (MMP) and natural tissue inhibitors of MMP (TIMP) in primary and established human cell lines, and in the nasopharyngeal secretions (NPS) of human infants infected with RSV or PIV. Using ELISA and multiplex-based assays, MMP-9 and TIMP-1 proteins were, respectively, detected in 66/67 and 67/67 NPS. During PIV or RSV infection TIMP-1 concentrations were associated with hypoxic bronchiolitis. TIMP-1 amounts were also negatively correlated with O2 saturation, and positively correlated with IL-6, MIP-1,, and G-CSF amounts following RSV infection. IL-6, MIP-1,, and G-CSF were negatively correlated with O2 saturation during RSV infection. Acute respiratory tract disease was not associated with MMP-9 protein/protease activity. Additional studies using real-time quantitative PCR suggested that MMP-9 mRNA copy numbers were elevated in normal human bronchial epithelial (NHBE) cells infected with RSV, while TIMP-1 and TIMP-2 were not increased. However, ELISA did not reveal MMP-9 protein in the NHBE cell culture supernatants. Hence, the data implied that airway epithelial cells were not the primary source of MMP or TIMP following paramyxovirus infection. Taken together, the data suggested that paramyxovirus infection perturbs MMP-9/TIMP-1 homeostasis that in turn may contribute to the severity of respiratory tract disease. J. Med. Virol. 79:447,456, 2007. © 2007 Wiley-Liss, Inc. [source]


Leucocyte populations in respiratory syncytial virus-induced bronchiolitis

JOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 2 2001
PK Smith
Objectives: To enumerate the cellular composition of the airways in infants with acute bronchiolitis. Methodology: Cells were obtained by airway lavage from the upper and lower airway and the peripheral blood of infants with respiratory syncytial virus (RSV)+ bronchiolitis, RSV, bronchiolitis and age-matched controls. Results: Neutrophils are the predominant cells present in the upper and lower airway. Neutrophils are present at a higher number/unit volume in the airway than in the peripheral blood. Conclusions: Neutrophils, being the dominant cellular infiltrate into the airway, are likely to contribute to the pathophysiology of bronchiolitis. Therapies targeted at limiting neutrophil influx or neutrophil-mediated damage in the airway may have a therapeutic role. [source]


Randomized controlled trial of nebulized adrenaline in acute bronchiolitis

PEDIATRIC ALLERGY AND IMMUNOLOGY, Issue 2 2003
Suriyanarayanapillai Hariprakash
Use of both l -epinephrine and racemic epinephrine (adrenaline) has improved clinical symptoms and composite respiratory scores in acute bronchiolitis. The objective of this randomized double-blind placebo-controlled study was to assess whether there was sufficient improvement in clinical state to reduce hospital admissions. Seventy-five infants aged 1 month to 1 year with a clinical diagnosis of acute bronchiolitis were treated with either 2 ml of 1:1000 nebulized adrenaline or 2 ml of nebulized normal saline administered after baseline assessment and 30 min later. Clinical respiratory parameters were recorded at 15-min intervals for a period of 2 h following the baseline assessment. Admission to hospital was the primary end-point and changes in respiratory parameters were secondary end-points. Fifty percent (19/38) of infants treated with adrenaline were discharged home compared with 38 percent (14/37) of those treated with saline. This 12 percent reduction in rate of admission is not statistically significant (95% CI of difference: ,10% to 35%). There was no difference between treated and placebo groups in respiratory rate, oxygen saturation, heart rate or a composite respiratory distress score at 30, 60 or 120 min post-treatment. In this study, nebulized epinephrine did not confer a significant advantage over nebulized saline in the emergency room treatment of acute bronchiolitis. [source]


A cost effectiveness analysis of omitting radiography in diagnosis of acute bronchiolitis,

PEDIATRIC PULMONOLOGY, Issue 2 2009
Jean Hai Ein Yong MASc
Abstract Objective To carry out a cost-effectiveness analysis of omitting chest radiography in the diagnosis of infant bronchiolitis. Hypothesis Omitting chest radiographs in the diagnosis of typical bronchiolitis was expected to reduce costs without adversely affecting the detection rate of alternate diseases. Study Design An economic evaluation was conducted using clinical and health resources. Emergency department (ED) physicians provided diagnoses pre- and post-radiography as well as a management plan. The primary outcome was the diagnostic accuracy (false-negative rate) of alternate diagnoses with and without X-ray. The incremental costs of omitting radiography in comparison to routine radiography per patient were assessed from a health system perspective. Patient Selection We studied 265 infants, 2,23 months old, presenting at the ED with typical bronchiolitis. Patients with pre-existing conditions or radiographs were omitted from the study. Methodology Expected costs to the health care system of including and excluding chest radiographs were compared, including costs associated with misdiagnosis. Results All alternate diagnoses (two cases) were missed by ED physicians pre- and post-radiography, resulting in a 100% false negative rate. The specificity in detecting alternate diseases was 96.6% pre-radiography and 88.6% post-radiography. Of the 17 cases of coexistent pneumonia, 88% were missed pre-radiography and 59% post-radiography, with respective false positive rates of 10.5% and 16.1%. Omission of routine chest radiograph saved CDN $59 per patient, primarily due to savings in radiography and hospitalization costs. The economic benefit persisted after the inpatient length of stay, ED overhead and radiograph costs were varied. Conclusion For infants with typical bronchiolitis, omitting radiography is cost saving without compromising diagnostic accuracy of alternate diagnoses and of associated pneumonia. Pediatr Pulmonol. 2009; 44:122,127. © 2009 Wiley-Liss, Inc. [source]


Eosinophil cationic protein in infants with respiratory syncytial virus bronchiolitis: Predictive value for subsequent development of persistent wheezing

PEDIATRIC PULMONOLOGY, Issue 6 2001
Massimo Pifferi MD
Abstract Infants with acute bronchiolitis during the first months of life are at increased risk of developing persistent wheezing and bronchial asthma later in life. The study of eosinophil cationic protein (ECP) suggests that eosinophil-related inflammatory mechanisms may play a role in respiratory syncytial virus (RSV) bronchiolitis. The aim of our study was to verify whether serum ECP (s-ECP) measurements are useful in predicting the development of persistent wheezing in children affected by RSV bronchiolitis during a 5 years follow-up period. Forty-eight infants were enrolled prospectively (mean age: 153.5 days). All had a clinical and radiological diagnosis of acute bronchiolitis and confirmed RSV infection. Peripheral eosinophil counts, levels of s-ECP, and serum IgE concentrations were measured during bronchiolitis. Five years later the children were re-evaluated in regard to their respiratory symptoms (standardized questionnaires) and atopic status (specific IgE levels). We observed significantly higher s-ECP levels (P <,0.001) at enrollment in subjects who developed persistent wheezing compared to subjects who did not show late wheezing. Initial s-ECP values allowed significant and correct prediction of persistent wheezing (P <,0.001). The risk to develop respiratory symptoms was 9.73 higher for infants with s-ECP levels ,,8,,g/L than for those with s-ECP levels <8,,g/L (P <,0.0001). In conclusion, our study suggests that s-ECP levels in infants with bronchiolitis are useful in predicting the risk to develop wheezing in the subsequent 5 years. Pediatr Pulmonol. 2001; 31:419,424. © 2001 Wiley-Liss, Inc. [source]


Increased laryngeal lavage lipid-laden macrophage index during acute bronchiolitis

ACTA PAEDIATRICA, Issue 7 2007
Chang Keun Kim
Abstract Aim: To investigate aspiration risks associated with bronchiolitis in infants using the lipid-laden macrophage index (LLMI) from laryngeal lavages. Methods: Laryngeal lavages from 29 infants with acute bronchiolitis caused by respiratory syncytial virus were evaluated (acute stage). Repeated studies were then performed at 3,4 weeks after the initial study (remission stage). Lavage cell counts and differentials were determined. The amount of lipid per single macrophage was evaluated and the LLMI was determined by evaluating 100 cells. In addition, 24-h pH monitoring (pHm) was performed in 16 patients. Results: The LLMIs in the acute stage were significantly higher than those in the remission stage (p < 0.05). The neutrophil percentage of the laryngeal lavage correlated significantly with the LLMI (r = 0.707, p < 0.0001) during the acute stage of bronchiolitis. When patients were divided into pHm-positive (n = 5) and pHm-negative (n = 11) subgroups, a significant decrease in LLMI between acute and remission stages was noted among the pHm-positive (p < 0.01) subgroup, but not in the pHm-negative subgroup. Conclusion: These findings suggest that there is a transient increased LLMI in patients with bronchiolitis, which could be caused by gastroesophageal reflux. [source]