Diagnostic and economic evaluation of a point-of-care test for respiratory syncytial virus.

Respiratory syncytial virus is a common cause of bronchiolitis. Historically, point-of-care tests have involved antigen detection technology with limited sensitivity. The aim of this study was to prospectively evaluate the diagnostic accuracy and model the economic impact of the Roche cobas® Liat® point-of-care influenza A/B and respiratory syncytial virus test. The "DEC-RSV" study was a multi-centre, prospective, observational study in children under 2 years presenting with viral respiratory symptoms. A nasopharyngeal aspirate sample was tested using the point-of-care test and standard laboratory-based procedures. The primary outcome was accuracy of respiratory syncytial virus detection. The cost implications of adopting a point-of-care test were modelled using study data. A total of 186 participants were recruited, with both tests performed on 177 samples. The point-of-care test was invalid for 16 samples (diagnostic yield 91%) leaving 161 available for primary analysis. After resolving discrepancies, the cobas® Liat® respiratory syncytial virus test had 100.00% (95% CI 96.07%-100.00%) sensitivity and 98.53% (95% CI 92.08%-99.96%) specificity. Median time to result was 0.6 h (interquartile range (IQR) 0.5-1) for point-of-care testing and 28.9 h (IQR 26.3-48.1) for standard laboratory testing. Estimated non-diagnostic cost savings for 1000 patients, based on isolation decision-making on point-of-care test result, were £57 010, which would increase to £94 847 when cohort nursing is used. In young children the cobas® Liat® point-of-care respiratory syncytial virus test has high diagnostic accuracy using nasopharyngeal aspirates (currently an off-licence sample type). Time to result is clinically important and was favourable compared to laboratory-based testing. The potential exists for cost savings when adopting the point-of-care test.

Accuracy of the interpretation of chest radiographs for the diagnosis of paediatric pneumonia.

INTRODUCTION: World Health Organization (WHO) radiological classification remains an important entry criterion in epidemiological studies of pneumonia in children. We report inter-observer variability in the interpretation of 169 chest radiographs in children suspected of having pneumonia. METHODS: An 18-month prospective aetiological study of pneumonia was undertaken in Northern England. Chest radiographs were performed on eligible children aged ≤16 years with clinical features of pneumonia. The initial radiology report was compared with a subsequent assessment by a consultant cardiothoracic radiologist. Chest radiographic changes were categorised according to the WHO classification. RESULTS: There was significant disagreement (22%) between the first and second reports (kappa = 0.70, P<0.001), notably in those aged <5 years (26%, kappa = 0.66, P<0.001). The most frequent sources of disagreement were the reporting of patchy and perihilar changes. CONCLUSION: This substantial inter-observer variability highlights the need for experts from different countries to create a consensus to review the radiological definition of pneumonia in children.

Changing clinical practice: management of paediatric community-acquired pneumonia.

RATIONALE AND AIM: To compare clinical features and management of paediatric community-acquired pneumonia (PCAP) following the publication of UK pneumonia guidelines in 2002 with data from a similar survey at the same hospitals in 2001-2002 (pre-guidelines). METHODS: A prospective survey of 11 hospitals in Northern England was undertaken during 2008-2009. Clinical and laboratory data were recorded on children aged ≤16 years who presented with clinical and radiological features of pneumonia. RESULTS: 542 children were included. There was a reduction in all investigations performed (P < 0.001) except C-reactive protein (P = 0.448) between surveys. These included full blood count (76% to 61%); blood culture (70% to 53%) and testing of respiratory secretions for viruses (24% to 12%) and bacteria (18% to 8%). Compared to pre-guidelines, there was a reduction in the use of intravenous antibiotics as a proportion of the total prescribed from 47% to 36% (P < 0.001) and a change in the route of antibiotic administration with increasing preference for oral alone (16% pre-compared to 50% post-guidelines, P < 0.001). CONCLUSION: Apart from the acute phase reactants that should not be measured routinely, these changes are in line with the guideline recommendations. Improvements in antibiotic use are possible and have implications for future antimicrobial stewardship programmes. Further work using cost-effectiveness analysis may also demonstrate a financial benefit to health services from adoption of guidelines.

Aetiology of paediatric pneumonia after the introduction of pneumococcal conjugate vaccine.

We describe the aetiology of community-acquired pneumonia in children before and after the introduction of the pneumococcal conjugate vaccination (PCV) programme in 2006. Prospective studies were conducted in 2001-2002 (pre-vaccine) and 2009-2011 (post-vaccine) of children aged 0-16 years with radiologically confirmed pneumonia seen in hospital. Investigations included culture, serology, immunofluorescence antibody and urine antigen testing, with an increased use of PCR assays and expanded panels of pathogens in the post-vaccine study. 241 and 160 children were enrolled in the pre- and post-vaccine studies, respectively (73% aged <5 years). Identification of a causative pathogen was higher post-vaccination (61%) than pre-vaccination (48.5%) (p=0.019). Rates of bacterial infections were not different between post- and pre-vaccine studies (17.5% versus 24%, p=0.258). Viral (31%) and mixed (12.5%) infections were found more often post-vaccination (19.5%, p=0.021) than pre-vaccination (5%, p=0.015). Rates of identified pneumococcal infections were comparable between pre- and post-vaccine studies (14.7% versus 17.4%, p=0.557). Diagnosis of pneumococcal infection post-vaccination improved when PCR was used compared to culture (21.6% versus 6%, p=0.0004). Serotypes included in PCV13 but not PCV7 were identified in 75% (18 out of 24) post-vaccination. Infection with nonvaccine pneumococcal serotypes continues to be a significant cause of pneumonia in children in the UK.

Pneumococcal diagnosis and serotypes in childhood community-acquired pneumonia.

The 7-valent pneumococcal conjugate vaccine (PCV7) was introduced routinely in the UK from September 2006 and replaced by PCV13 in 2010. In a prospective study from 2009 to 2011 of 160 children aged ≤16 years with radiologically confirmed pneumonia, likely pneumococcal infections were identified in 26%. Detection of pneumococci was improved with polymerase chain reaction compared to culture (21.6% versus 6% of children tested, P = 0.0004). Where serotyping was possible, all (n = 23) were non-PCV7 but PCV13 serotypes; 1 (43.5%), 3 (21.7%), 7A/F, and 19A (17.4% each).

All that wheezes is not asthma: a 6-year-old with foreign body aspiration and no suggestive history.

The authors report the case of a 6-year-old girl, presenting with a 4-month history of wheeze associated with barking cough which frequently became wet requiring antibiotics. Her care was transferred to a paediatrician with specialist interest in paediatric respiratory medicine when she had continued symptoms despite bronchodilators and oral steroids for suspected asthma. Spirometry showed a forced expiratory volume 1 of 79% with no evidence of reversibility. The child was investigated for chronic wet cough. Immunoglobulins, sweat test and chest x-ray were all normal. There was no history suggestive of foreign body aspiration (FBA). Tracheomalacia was considered in view of the nature of the cough. The recurrence of an unusual inspiratory noise prompted referral for bronchoscopy. A small piece of plastic tube was removed from the bronchus intermedius. All symptoms resolved. The importance of clinical assessment to ascertain 'wheeze' when acutely unwell is emphasised. Current literature concerning FBA is reviewed.

Not all infantile respiratory distress in winter is bronchiolitis: congenital lobar emphysema.

The authors report the case of a 4-week-old male infant presented during the winter period with respiratory distress. He had a 3 day history of cough and coryza, and a 2 day history of breathlessness and reduced feeding. He had evidence of tachypnoea, subcostal recession and hypoxia on examination. An initial diagnosis of bronchiolitis was made. The authors explore how the correct diagnosis of congenital lobar emphysema (CLE) was reached, highlighting key clinical signs and investigations. He had evidence of a hyperinflated right middle lobe, with collapse of right upper and lower lobes and left upper lobe with associated mediastinal shift on chest x-ray (CXR) and CT scan. He was referred to the regional Paediatric Cardiothoracic Centre where right middle lobectomy was performed with complete resolution of his respiratory distress and re-expansion of the compressed lobes on CXR. Current literature concerning CLE is reviewed.

Cavitatory lung disease complicating empyema in children.

OBJECTIVE: The incidence of empyema has increased dramatically in children in the UK over the last decade. Streptococcus pneumoniae (S. pneumoniae) serotype 1 is the dominant serotype. We have observed more pneumatocoele and bronchopleural fistulae formation over this time. AIM: Our aim was to determine the number of children who developed cavitatory disease as a complication of empyema at a tertiary referral centre and whether there was any association with S. pneumoniae serotype 1. METHOD: We reviewed 75 cases presenting with empyema or parapneumonic effusion between February 1997 and July 2003. Bacterial culture and pneumococcal antigen detection were supplemented by real-time polymerase chain reaction (PCR) to detect pneumococcal DNA. RESULTS: Cavitatory disease was present in 15 cases. Three children developed bronchopleural fistulae. S. pneumoniae was detected in 13 of 15 cases (4 cases serotype 1, 3 serotype 3, 2 serotype 14, and 2 serotype 9V; serotype assay was not performed in two cases). Staphylococcus aureus (S. aureus) was isolated in one case. No organism was isolated in the final case but an Antistreptolysin-O titre was >800 U/ml on two occasions suggestive of group A streptococcal infection. CONCLUSION: Twenty percentage of cases of empyema in our series were complicated by cavitatory lung disease. It is an important complication of childhood empyema associated classically with S. aureus, but these data suggest that S. pneumoniae now appears to be the main cause. There does not seem to be an association with any particular serotype.