Implementation of a Children's Safe Asthma Discharge Care Pathway Reduces the Risk of Future Asthma Attacks in Children-A Retrospective Quality Improvement Report

BACKGROUND

Many children attend Emergency Departments (ED) and Out of Hours (OoH) frequently for acute asthma. Follow up care is often suboptimal leaving these children at risk of a future attacks. We report on the development, implementation and evaluation of a safe asthma discharge care pathway (SADCP).

METHODS

This is a retrospective report on the development, implementation and evaluation of outcomes of a SADCP. The pathway was based on the Teach-to-goal educational methodology that supported the mastery correct inhaler technique and ability to action the personalized asthma action plan (PAAP). Children with frequent asthma attacks were entered as they were discharged from the Emergency Department or ward. The first training session occurred within 1-3 weeks of the index asthma attack with 2 further sessions in the following 8 weeks. Children exiting the pathway were discharged either back to primary care or to a hospital clinic.

RESULTS

81 children entered the pathway (median age 5 years) with 72 discharged from the ED and 9 from the medical wards of the Royal Belfast Hospital for Sick Children. At pathway entry 13% had correct inhaler technique, 10% had a Personalized Asthma Action Plan (PAAP), and 5% had >80% (45% >50%) repeat refill evidence of adherence to inhaled corticosteroid over the previous 12 months. On pathway exit all children demonstrated correct inhaler technique and were able to action their PAAP. One year later 51% and 95% had refill evidence of >80% and >50% adherence. Comparisons of the 12 months before and 12 months after exit from the pathway the median number of emergency ED or OoH asthma attendances and courses of oral corticosteroids reduced to zero with >75% having no attacks requiring this level of attention. Similar findings resulted when the SADCP was implemented in a district general hospital pediatric unit.

CONCLUSION

Implementing an asthma care pathway, using Teach-to-Goal skill training methods and frequent early reviews after an index asthma attack can reduce the future risk of asthma attacks in the next 6 to 12 months.

Seroprevalence of SARS-CoV-2 antibodies in children of United Kingdom healthcare workers: a prospective multicentre cohort study protocol

BACKGROUND

A novel coronavirus SARS-CoV-2 has been responsible for a worldwide pandemic. Children typically have very mild, or no, symptoms of infection. This makes estimations of seroprevalence in children difficult. Research is therefore required to determine the seroprevalence of SARS-CoV-2 antibodies in children. The primary objective of this study is to report the seroprevalence of SARS-CoV-2 IgM and/or IgG antibodies in healthy children at baseline, 2 months and 6 months. This is the only longitudinal UK study of seroprevalence in an exclusively paediatric population. Determining the changing seroprevalence is of vital public health importance and can help inform decisions around the lifting of paediatric specific social distancing measures such as school closures and the cancellation of routine paediatric hospital services.

METHODS AND ANALYSIS

1000 healthy children of healthcare workers aged between 2 and 15 years will be recruited from five UK sites (Belfast, Cardiff, Glasgow, London and Manchester). The children will undergo phlebotomy at baseline, 2 months and 6 months to measure IgM and/or IgG positivity to SARS-CoV-2. A sample size of 675 patients is required to detect a 5% change in seroprevalence at each time point assuming an alpha of 0.05 and a beta of 0.2. Adjusted probabilities for the presence of IgG and/or IgM antibodies and of SARS-CoV-2 infection will be reported using logistic regression models where appropriate.

ETHICS AND DISSEMINATION

Ethical approval was obtained from the London - Chelsea Research Ethics Committee (REC Reference-20/HRA/1731) and the Belfast Health & Social Care Trust Research Governance (Reference 19147TW-SW). Results of this study will be made available as preprints and submitted for publication in peer-reviewed journals.

TRIAL REGISTRATION NUMBER

NCT0434740; Results.

Blood eosinophils as a marker of likely corticosteroid response in children with preschool wheeze: time for an eosinophil guided clinical trial?

Childhood wheezing is common particularly in children under the age of 6 years and in this age group is generally referred to as preschool wheezing. Particular diagnostic and treatment uncertainties exist in these young children due to the difficulty in obtaining objective evidence of reversible airways narrowing and inflammation. A diagnosis of asthma depends on the presence of relevant clinical signs and symptoms and the demonstration of reversible airways narrowing on lung function testing, which is difficult to perform in young children. Few treatments are available and inhaled corticosteroids are the recommended preventer treatment in most international asthma guidelines. There is, however, considerable controversy about its effectiveness in children with preschool wheeze and a corticosteroid responder phenotype has not been established. These diagnostic and treatment uncertainties in conjunction with the knowledge of corticosteroid side effects, in particular the reduction of growth velocity, have resulted in a variable approach to inhaled corticosteroid prescribing by medical practitioners and a reluctance in carers to regularly administer the treatment. Identifying children who are likely responders to corticosteroid therapy would be a major benefit in the management of this condition. Eosinophils have emerged as a promising biomarker of corticosteroid responsive airways disease, and evaluation of this biomarker in sputum has successfully been employed to direct management in adults with asthma. Obtaining sputum from young children is time consuming and difficult, and it is hard to justify more invasive procedures such as a bronchoscopy in young children routinely. Recently, in children, interest has shifted to assessing the value of less invasive biomarkers of likely corticosteroid response and the biomarker 'blood eosinophils' has emerged as an attractive candidate. The aim of this review was to summarize the evidence for blood eosinophils as a predictive biomarker for corticosteroid responsive disease with a particular focus on the difficult area of preschool wheeze.

Efficacy and long-term outcomes of palivizumab prophylaxis to prevent respiratory syncytial virus infection in infants with cystic fibrosis in Northern Ireland

BACKGROUND

RSV causes considerable morbidity and mortality in children. In cystic fibrosis (CF) viral infections are associated with worsening respiratory symptoms and bacterial colonization. Palivizumab is effective in reducing RSV hospitalization in high risk patient groups. Evidence regarding its effectiveness and safety in CF is inconclusive. CF screening in N. Ireland enabled timely palivizumab prophylaxis, becoming routine in 2002.

OBJECTIVES

To determine the effect of palivizumab on RSV-related hospitalization and compare lung function and bacterial colonization at age 6 years for those born pre- and post-introduction of palivizumab prophylaxis.

METHODS

A retrospective audit was conducted for all patients diagnosed with CF during the period from 1997 to 2007 inclusive. RSV-related hospitalization, time to Pseudomonas aeruginosa (PA) 1st isolate, lung function and growth parameters were recorded. Comparisons were made for outcomes pre- and post-introduction of routine palivizumab administration in 2002. A cost evaluation was also performed.

RESULTS

Ninety-two children were included; 47 pre- and 45 post-palivizumab introduction. The overall RSV-positive hospitalization rate was 13%. The relative risk of RSV infection in palivizumab non-recipients versus recipients was 4.78 (95%CI: 1.1-20.7), P = 0.027. Notably, PA 1st isolate was significantly earlier in the palivizumab recipient cohort versus non-recipient cohort (median 57 vs. 96 months, P < 0.025) with a relative risk of 2.5. Chronic PA infection at 6 years remained low in both groups, with similar lung function and growth parameters. Total costs were calculated at £96,127 ($151,880) for the non-recipient cohort versus £137,954 ($217,967) for the recipient cohort.

CONCLUSION

Palivizumab was effective in reducing RSV-related hospitalization infection in CF patients. Surprisingly, we found a significantly earlier time to 1st isolate of PA in palivizumab recipients which we could not explain by altered or improved diagnostic tests.

Genetic susceptibility to invasive meningococcal disease: MBL2 structural polymorphisms revisited in a large case-control study and a systematic review

Invasive infection caused by Neisseria meningitidis is a worldwide public health problem. Previous reports have indicated that carriage of common 'defective' structural polymorphisms of the host mannose-binding lectin gene (MBL2) greatly increases an individual's risk of developing the disease. We report the largest case-control study so far to investigate the effect of these polymorphisms in meningococcal disease (296 PCR-positive cases and 5196 population controls, all of European ancestry) and demonstrate that no change in risk is associated with the polymorphisms overall or in any age-defined subgroup. This finding contrasts with two smaller studies that reported an increase in risk. A systematic review of all studies of MBL2 polymorphisms in people of European ancestry published since 1999, including 24,693 individuals, revealed a population frequency of the combined 'defective'MBL2 allele of 0.230 (95% confidence limits: 0.226-0.234). The past reported associations of increased risk of meningococcal disease were because of low 'defective' allele frequencies in their study control populations (0.13 and 0.04) that indicate systematic problems with the studies. The data from our study and all other available evidence indicate that MBL2 structural polymorphisms do not predispose children or adults to invasive meningococcal disease.

Molecular testing of respiratory swabs aids early recognition of meningococcal disease in children

Early meningococcal disease (MD) diagnosis is difficult. We assessed rapid molecular testing of respiratory specimens. We performed genotyping of respiratory swabs, blood, and cerebrospinal fluid from children with suspected disease and nasal swabs (NSs) from matched controls. Thirty-nine of 104 suspected cases had confirmed disease. Four controls were carriers. Throat swab ctrA and porA testing for detection of disease gave a sensitivity of 81% (17/21), specificity of 100% (44/44), positive predictive value (PPV) of 100% (17/17), negative predictive value (NPV) of 92% (44/48), and relative risk of 12. NS ctrA and porA testing gave a sensitivity of 51% (20/39), specificity of 95% (62/65), PPV of 87% (20/23), NPV of 77% (62/81), and relative risk of 4. Including only the 86 NSs taken within 48 h of presentation, the results were sensitivity of 60% (18/30), specificity of 96% (54/56), PPV of 90% (18/20), NPV of 82% (54/66), and relative risk of 5. Swab type agreement was excellent (kappa 0.80, P < 0.001). There was exact phylogenetic agreement from different specimen sites for individuals. Carried genosubtypes were P1.7 and P1.21-7. Prehospital rapid molecular testing of easily obtained respiratory specimens could accelerate diagnosis of MD.

Review article: reflux and its consequences--the laryngeal, pulmonary and oesophageal manifestations. Conference held in conjunction with the 9th International Symposium on Human Pepsin (ISHP) Kingston-upon-Hull, UK, 21-23 April 2010

BACKGROUND

Gastro-oesophageal reflux disease (GERD) is one of the commonest diseases of Western populations, affecting 20 to 30% of adults. GERD is multifaceted and the classical oesophageal symptoms such as heartburn and regurgitation often overlap with atypical symptoms that impact upon the respiratory system and airways. This is referred to as extra-oesophageal reflux disease (EERD), or laryngopharyngeal reflux (LPR), which manifests as chronic cough, laryngitis, hoarseness, voice disorders and asthma.

AIM

The 'Reflux and its consequences' conference was held in Hull in 2010 and brought together a multidisciplinary group of experts all with a common interest in the many manifestations of reflux disease to present recent research and clinical progress in GERD and EERD. In particular new techniques for diagnosing reflux were showcased at the conference.

METHODS

Both clinical and non-clinical key opinion leaders were invited to write a review on key areas presented at the `Reflux and its consequences' conference for inclusion in this supplement.

RESULTS AND CONCLUSION

Eleven chapters contained in this supplement reflected the sessions of the conference and included discussion of the nature of the refluxate (acid, pepsin, bile acids and non-acid reflux); mechanisms of tissue damage and protection in the oesophagus, laryngopharynx and airways. Clinical conditions with a reflux aetiology including asthma, chronic cough, airway disease, LPR, and paediatric EERD were reviewed. In addition methods for diagnosis of reflux disease and treatment strategies, especially with reference to non-acid reflux, were considered.

Respiratory viral infection in lower airways of asymptomatic children

Aim:  The aim of this study was to determine if asthmatic children have viruses more commonly detected in lower airways during asymptomatic periods than normal children.

Methods:  Fifty‐five asymptomatic children attending elective surgical procedures (14 with stable asthma, 41 normal controls) underwent non‐bronchoscopic bronchoalveolar lavage. Differential cell count and PCR for 13 common viruses were performed.

Results:  Nineteen (35%) children were positive for at least one virus, with adenovirus being most common. No differences in the proportion of viruses detected were seen between asthmatic and normal ‘control’ children. Viruses other than adenovirus were associated with higher neutrophil counts, suggesting that they caused an inflammatory response in both asthmatics and controls (median BAL neutrophil count, 6.9% for virus detected vs. 1.5% for virus not detected, p = 0.03).

Conclusions:  Over one‐third of asymptomatic children have a detectable virus (most commonly adenovirus) in the lower airway; however, this was not more common in asthmatics. Viruses other than adenovirus were associated with elevated neutrophils suggesting that viral infection can be present during relatively asymptomatic periods in asthmatic children.

A meta-analysis of the association between Caesarean section and childhood asthma

BACKGROUND

Children born by Caesarean section have modified intestinal bacterial colonization and consequently may have an increased risk of developing asthma under the hygiene hypothesis. The results of previous studies that have investigated the association between Caesarean section and asthma have been conflicting.

OBJECTIVE

To review published literature and perform a meta-analysis summarizing the evidence in support of an association between children born by Caesarean section and asthma.

METHODS

MEDLINE, Web Science, Google Scholar and PubMed were searched to identify relevant studies. Odds ratio (OR) and 95% confidence interval (CI) were calculated for each study from the reported prevalence of asthma in children born by Caesarean section and in control children. Meta-analysis was then used to derive a combined OR and test for heterogeneity in the findings between studies.

RESULTS

Twenty-three studies were identified. The overall meta-analysis revealed an increase in the risk of asthma in children delivered by Caesarean section (OR=1.22, 95% CI 1.14, 1.29). However, in this analysis, there was evidence of heterogeneity (I(2)=46%) that was statistically significant (P<0.001). Restricting the analysis to childhood studies, this heterogeneity was markedly decreased (I(2)=32%) and no longer attained statistical significance (P=0.08). In these studies, there was also evidence of an increase (P<0.001) in the risk of asthma after Caesarean section (OR=1.20, 95% CI 1.14, 12.6).

CONCLUSION

In this meta-analysis, we found a 20% increase in the subsequent risk of asthma in children who had been delivered by Caesarean section.

Children with stable asthma have reduced airway matrix metalloproteinase-9 and matrix metalloproteinase-9/tissue inhibitor of metalloproteinase-1 ratio

BACKGROUND

Childhood asthma is characterized by inflammation of the airways. Structural changes of the airway wall may also be seen in some children early in the course of the disease. Matrix metalloproteinases (MMPs) are key mediators in the metabolism of the extracellular matrix (ECM).

OBJECTIVE

To investigate the balance of MMP-8, MMP-9 and tissue inhibitor of metalloproteinases (TIMP)-1 in the airways of children with asthma.

METHODS

One hundred and twenty-four children undergoing elective surgical procedures also underwent non-bronchoscopic bronchoalveolar lavage (BAL). MMP-8, MMP-9 and TIMP-1 were measured by ELISA.

RESULTS

There was a significant reduction in MMP-9 in atopic asthmatic children (n=31) compared with normal children (n=30) [median difference: 0.57 ng/mL (95% confidence interval: 0.18-1.1 ng/mL)]. The ratio of MMP-9 to TIMP-1 was also reduced in asthmatic children. Levels of all three proteins were significantly correlated to each other and to the relative proportions of particular inflammatory cells in BAL fluid (BALF). Both MMP-8 and MMP-9 were moderately strongly correlated to the percentage neutrophil count (r=0.40 and 0.47, respectively, P<0.001).

CONCLUSIONS

An imbalance of MMPs and their inhibitors occurs in children with well-controlled asthma, which may indicate early derangement of the metabolism of the ECM.

A cluster randomised intervention trial of asthma clubs to improve quality of life in primary school children: the School Care and Asthma Management Project (SCAMP)

AIM

To evaluate the effectiveness of a programme of asthma clubs in improving quality of life in primary school children with asthma.

METHODS

A cluster randomised intervention trial was undertaken in 22 primary schools within the urban area of south and east Belfast, Northern Ireland. Schools were randomised in pairs to immediate or delayed groups. The study subjects comprised 173 children aged 7-11 years whose parents had notified the school of their asthma diagnosis. Children attended school based weekly clubs over an 8 week period. The main outcome measures were the interview administered Paediatric Quality of Life Questionnaire scores, ranging from 1 (worst) to 7 (best), spirometry, and inhaler technique.

RESULTS

Over 15 weeks, small but non-significant improvements in the overall quality of life score (mean 0.20; 95% confidence interval (CI) -0.20 to 0.61) and in each of its three components, activity limitation (0.20; -0.43 to 0.84), symptoms (0.23; -0.23 to 0.70), and emotional function (0.17; -0.18 to 0.52), were observed in the immediate compared with the delayed group. Inhaler technique at week 16 was markedly better in the immediate group, with 56% having correct technique compared with 15% in the delayed group. No significant effect of the intervention on spirometry results could be demonstrated.

CONCLUSION

This primary school based asthma education programme resulted in sustained improvements in inhaler technique, but changes in quality of life scores were not significant.

Monitoring growth in asthmatic children treated with high dose inhaled glucocorticoids does not predict adrenal suppression

AIMS

To determine whether routine outpatient monitoring of growth predicts adrenal suppression in prepubertal children treated with high dose inhaled glucocorticoid.

METHODS

Observational study of 35 prepubertal children (aged 4-10 years) treated with at least 1000 microg/day of inhaled budesonide or equivalent potency glucocorticoid for at least six months. Main outcome measures were: changes in HtSDS over 6 and 12 month periods preceding adrenal function testing, and increment and peak cortisol after stimulation by low dose tetracosactrin test. Adrenal suppression was defined as a peak cortisol < or =500 nmol/l.

RESULTS

The areas under the receiver operator characteristic curves for a decrease in HtSDS as a predictor of adrenal insufficiency 6 and 12 months prior to adrenal testing were 0.50 (SE 0.10) and 0.59 (SE 0.10). Prediction values of an HtSDS change of -0.5 for adrenal insufficiency at 12 months prior to testing were: sensitivity 13%, specificity 95%, and positive likelihood ratio of 2.4. Peak cortisol reached correlated poorly with change in HtSDS (rho = 0.23, p = 0.19 at 6 months; rho = 0.33, p = 0.06 at 12 months).

CONCLUSIONS

Monitoring growth does not enable prediction of which children treated with high dose inhaled glucocorticoids are at risk of potentially serious adrenal suppression. Both growth and adrenal function should be monitored in patients on high dose inhaled glucocorticoids. Further research is required to determine the optimal frequency of monitoring adrenal function.

Liquid chromatographic determination including simultaneous “on-cartridge” separation of ranitidine cisapride drug combinations from paediatric plasma samples using an automated solid-phase extraction procedure

HPLC methodology was investigated for the simultaneous determination of cisapride and ranitidine in small volume paediatric plasma samples. Such a simultaneous determination proved difficult due to the small sample volumes, the low concentrations of the drugs and the different log P values of the two compounds. The two drugs and their respective internal standards were separated "on-cartridge" using HLB Solid Phase Extraction cartridges and the samples quantified by individual HPLC methodologies. The technique has been applied successfully to 60 paediatric plasma samples containing both cisapride and ranitidine.

The effect of nicotine on basophil histamine release

BACKGROUND

Changes in the immune and inflammatory response are induced by smoking tobacco but underlying mechanisms remain to be elucidated.

OBJECTIVE

This study investigated the effect of nicotine agonists on histamine release from human basophils.

METHODS

Peripheral blood basophils were obtained from healthy volunteers. The effect of the nicotine agonists [-]-1-methyl-2-[3-pyridyl]pyrrolidine and (+)-nicotine di-p-toluoyltartrate salt on cell viability and anti-IgE induced histamine release was investigated.

RESULTS

Cell viability was not altered by preincubation with the agents for 15 min. Anti-IgE induced histamine release was significantly inhibited by preincubation (15 min, 37 degrees C) with [-]-1-methyl-2-[3-pyridyl]pyrrolidine at the highest concentration tested 10(-)3 M (p<0.01). Preincubation (15 min, 37 degrees C) with (+)-nicotine di-p-toluoyltartrate salt significantly inhibited anti-IgE induced histamine release at 10(-3)M and 10(-5) M (p<0.05).

CONCLUSIONS

This study has demonstrated that nicotine agonists inhibit histamine release from human basophils. Further studies examining the effect of smoking on basophil activation are required.

Cough . 2: Chronic cough in children

Chronic cough is a common problem in childhood. Viral infections are the most prevalent cause, but other rarer disorders should be excluded whenever cough appears unusually severe and/or frequent, and when there is evidence of failure to thrive and growth retardation. The younger the child, the more the need to exclude underlying disease at an early stage. Passive smoking is an important contributor to chronic cough in children. Chronic productive cough with purulent sputum is always reason for concern in children and is not common as a symptom of asthma. More or less specific diagnoses in children include cystic fibrosis, aspirated foreign body, congenital anatomic abnormalities and primary ciliary dyskinesia.

Non-bronchoscopic sampling and culture of bronchial epithelial cells in children

BACKGROUND

The bronchial epithelium is likely to play a vital role in airway diseases in children, such as asthma and viral-associated wheeze. In adults, studies with primary bronchial epithelial cells cultured from samples obtained by fibre-optic bronchoscopy have provided key insights into the role of the epithelial cell. However, it is difficult to justify bronchoscopy in children to obtain epithelial cells for research purposes.

OBJECTIVE

To examine the possibility of retrieving and culturing viable epithelial cells using a blind non-bronchoscopic method from children undergoing elective surgery.

METHODS

Subjects were children undergoing elective surgery under general anaesthesia. Following intubation, non-bronchoscopic bronchoalveolar lavage and non-bronchoscopic bronchial brushing were performed. A sheathed bronchial cytology brush was advanced through the endotracheal tube, wedged and then withdrawn 2-3 cm before gentle sampling was used to collect bronchial epithelial cells. Initial samples were used to characterize the number, type and viability of epithelial cells recovered compared to a control group of adults undergoing standard bronchoscopic sampling. Subsequent samples were used to establish primary bronchial epithelial cell cultures in children both with and without wheezing illness.

RESULTS

A total of 63 children underwent bronchial brushing [38 male; median age 7.1 years (1.0-14.2 years]. Initial samples (n=30) showed recovery of viable epithelial cells comparable to that from a single brush obtained via a bronchoscope in an adult control group (n=11). In 27 (82%) of the subsequent 33 samples obtained non-bronchoscopically from children, primary bronchial epithelial cell cultures were successfully established. There were no adverse effects attributable to sampling.

CONCLUSION

We have shown that non-bronchoscopic bronchial brushing is a safe and effective technique for recovering viable bronchial epithelial cells that consistently yield primary cultures. This method will facilitate examination of the role of the epithelium in paediatric disease.

T cell cytokine profiles in childhood asthma

BACKGROUND

An imbalance of T cell subsets in asthma with a predominance of Th2 type cells has been proposed. The aim of this study was simultaneously to detect surface markers and intracellular production of cytokines in T cells from the airways of children with and without asthma.

METHODS

Bronchoalveolar lavage (BAL) fluid was obtained by wedging a suction catheter into the distal airway immediately before elective surgery. Cells were stimulated with phorbol 12-myristrate 13-acetate (PMA) and ionomycin and intracytoplasmic cytokine retention was achieved using monensin. The cells were stained with the relevant antibodies and analysed by flow cytometry.

RESULTS

No statistical difference was observed between children with atopic asthma, atopic non-asthmatic subjects, and normal controls in the percentage of CD3+ cells producing interleukin (IL)-2 or IL-4. Interferon (IFN)gamma+ T cells were, however, present in a much higher percentage than either IL-2 or IL-4 positive cells. The percentage of IFNgamma+ T cells was significantly increased in subjects with atopic asthma (median 71.3%, interquartile range (IQR) 65.1-82.2, n=13) compared with both atopic non-asthmatic subjects (51.9%, IQR 37.2-70.3, n=12), p<0.05 and normal controls (58.1%, IQR 36.1-66.1, n=23), p<0.01.

CONCLUSIONS

These findings indicate that IFNgamma producing T cells are more abundant in the airways of children with atopic asthma than in atopic non-asthmatic subjects and controls. The proinflammatory activities of IFNgamma may play an important role in the pathogenesis of childhood asthma and may suggest that asthma is not simply a Th2 driven response.

Hypoglycemia due to adrenal suppression secondary to high-dose nebulized corticosteroid

High-dose inhaled corticosteroids, greater than 400 mcg per day of beclomethasone dipropionate or equivalent, can cause adrenal insufficiency, but a hypoglycemic crisis has not been reported with the use of nebulized corticosteroids. We describe a 21-month-old asthmatic boy who had a hypoglycemic seizure during a proven acute adrenal crisis secondary to high-dose nebulized budesonide treatment.

Exhaled nitric oxide correlates with airway eosinophils in childhood asthma

BACKGROUND

Exhaled nitric oxide has been proposed as a marker for airway inflammation in asthma. The aim of this study was to compare exhaled nitric oxide levels with inflammatory cells and mediators in bronchoalveolar lavage fluid from asthmatic and normal children.

METHODS

Children were recruited from elective surgical lists and a non-bronchoscopic bronchoalveolar lavage (BAL) was performed after induction of anaesthesia. Exhaled nitric oxide (parts per billion) was measured by two techniques: tidal breathing and restricted breath.

RESULTS

Median (interquartile range) exhaled nitric oxide measured by restricted breath was increased in asthmatics compared with normal children (24.3 (10.5-66.5) v 9.7 (6.5-16.5), difference between medians 14.6 (95% CI 5.1 to 29.9), p=0.001). In asthmatic children exhaled nitric oxide correlated significantly with percentage eosinophils (r=0.78, p<0.001 (tidal breathing) and r=0.78, p<0.001 (restricted breath)) and with eosinophilic cationic protein (r=0.53, p<0.01 (restricted breath)), but not with other inflammatory cells in the BAL fluid. The area under the receiver operator characteristic curves for the prediction of the presence of eosinophilic airways inflammation by exhaled nitric oxide (tidal and restricted) was 0.80 and 0.87, respectively.

CONCLUSIONS

Exhaled nitric oxide correlates closely with percentage eosinophils in BAL fluid in asthmatic children and is therefore likely to be a useful non-invasive marker of airway inflammation.

Outgrown asthma does not mean no airways inflammation

Although some asthmatic children seem to recover from their asthma, 30-80% develop asthma again in later life. The underlying risk factors are unknown. The hypothesis for this study was that children with apparently outgrown asthma would have underlying airway inflammation. Nonbronchoscopic bronchoalveolar lavage was performed on normal children (n=35) and children who had wheezed previously (n=35). Eosinophils were raised in the lavage fluid of atopic children who had apparently outgrown asthma (median (interquartile range) 0.36 (0.05-0.74) compared to controls 0.10 (0-0.18), p=0.002). There was no relationship between length of remission and degree of airways eosinophilia. Thus, there is persistent airways inflammation in some children with outgrown asthma and this may be a risk factor for future relapse.

Prevalence and awareness of excess weight in 13 and 14 year olds in Northern Ireland using recent international guidelines

Concern has been expressed in recent years over the rising trends in overweight and obesity, particularly in children in developed countries. No recent data were available for Northern Ireland, therefore measurements of height and weight were included in a study in Northern Ireland originally designed as part of an international study to estimate the prevalence of symptoms of asthma and atopy in childhood. Twenty-six schools across the province were sampled. 2484 children aged mainly 13 and 14 y completed questionnaires, and 2307 were weighed and measured. Using recently proposed international guidelines on defining overweight and obesity in children the prevalence of overweight in boys was 16%, with 4% being obese. In girls 16% were also overweight and 2% were obese. This concurs with figures for English and Scottish schoolchildren up to 12 y of age from 1994. Less than one-sixth of obese boys but more than one-third of obese girls were on weight-reducing diets (the majority self-prescribed), reflecting differing attitudes towards excess weight.

CONCLUSION

In line with figures in younger children from England and Scotland this study shows that 16% of boys and girls from Northern Ireland are classed as overweight using recent international guidelines. Only 15% of obese boys compared with 38% of obese girls stated that they were on weight-reducing diets.

The repeatability of nonbronchoscopic bronchoalveolar lavage differential cell counts

Airway inflammation in children can be assessed by nonbronchoscopic bronchoalveolar lavage (BAL). Little is known about the repeatability of cell counts in the BAL obtained. Children (n=43) attending for elective surgery were studied. Cell counts were obtained following a nonbronchoscopic lavage. Two samples were obtained with either: 1) the catheter wedged in the same position (n=21) or 2) the catheter reinserted and wedged again (n=22). Slides (n=30) from nonbronchoscopic lavage samples were selected at random and two independent observers counted 500 cells on each slide on two occasions. The repeatability of the lavage sampling and cell counting was assessed for different cell types. The inter- and intra-observer repeatability for the differential cell counting demonstrated that there was good repeatability for all cell types except lymphocytes (interobserver: Lin's concordance coefficient 0.42; repeatability coefficient 0.66). Quantification of eosinophil (%) was highly repeatable using either method (Lin's concordance coefficient 1) 0.99, 2) 0.95; repeatability coefficient 1) 0.58, 2) 1.36). Nonbronchoscopic lavage is a repeatable technique for the quantification of eosinophils. Variation in the sampling method can be reduced by taking two separate samples and averaging the differential cell counts. Furthermore, increasing the number of cells counted should ensure accurate quantification of lymphocytes.

The use of hydrophilic lipophilic balanced (HLB) copolymer SPE cartridges for the extraction of diclofenac from small volume paediatric plasma samples

The extraction of diclofenac from spiked aqueous and plasma samples by liquid-liquid extraction (LLE) and solid phase extraction (SPE) methods is compared. The SPE methodology utilised a hydrophilic lipophilic balanced (HLB) copolymer as the extraction phase. Using a literature HPLC method, a calibration curve for diclofenac was constructed in the range 1.0-50.0 microg/ml. Diclofenac spiked samples (aqueous and plasma) were extracted by LLE and SPE methodologies. The SPE resulted in higher extraction efficiencies (mean 94.9%) than the LLE (mean 78.9%) with %R.S.D.s similar in both methods (3.2 vs. 2.1%, respectively). The SPE method was suitable for the extraction of diclofenac from small volume paediatric plasma samples.

Acute asthma exacerbations and air pollutants in children living in Belfast, Northern Ireland

The incidence of childhood asthma, a common condition, is on the rise worldwide. Despite reductions in the emission of urban smoke, traffic pollution is now a major worldwide problem. Belfast, Northern Ireland, is an old industrial city with major pollution problems. In this study, the authors investigated the rates of acute asthma admissions to Belfast's major children's emergency department. The admissions were studied, relative to day-to-day fluctuations in thoracic particulate matter, sulfur dioxide, nitrogen dioxide, nitric oxide, oxides of nitrogen, ozone, carbon monoxide, benzene, temperature, and rainfall. Daily admissions for acute asthma at the emergency department of the Royal Belfast Hospital and average daily pollution were recorded for the 3-yr period between January 1, 1993, and December 31, 1995. The authors used Poisson regression to assess independent association(s). Individually, small associations were seen for thoracic particulate matter (relative risk = 1.10), sulfur dioxide (relative risk = 1.09), nitrogen dioxide (relative risk = 1.11), nitric oxide (relative risk = 1.07), oxides of nitrogen (relative risk = 1.10), carbon monoxide (relative risk = 1.07), and benzene (1.14); no associations were noted between meteorological factors (temperature and rainfall) or ozone and asthma emergency-department admissions. The authors adjusted for the aforementioned parameters, and benzene level was the only variable associated independently with asthma emergency-department admissions in children. Benzene may be a more reliable method of measuring exposure to vehicle exhaust emissions than measurements of other pollutants.

Antioxidants and protein carbonyls in bronchoalveolar lavage fluid of children: normal data

Antioxidant-oxidant imbalances in bronchoalveolar lavage fluid (BAL) are thought to contribute to oxidative stress in respiratory disease. However, normal reference ranges for BAL antioxidants and oxidized proteins in children are not available. In this study, we recruited 124 children attending for elective surgery for a noninflammatory condition; 83 were nonasthmatic, nonatopic (N) and 41 were nonasthmatic, atopic (NA). A nonbronchoscopic lavage was performed and ascorbate, uric acid, alpha-tocopherol, and protein carbonyl (as a measure of oxidative damage) concentrations were determined in BAL fluid. The 95% reference range was 0.112-1.897 micromol/L for ascorbate, 0.149-2.163 micromol/L for urate, 0.0029-0.066 micromol/L for alpha-tocopherol, and 0.280-4.529 nmol/mg for protein carbonyls in BAL fluid. Age, gender, and exposure to environmental tobacco smoke did not affect the concentration of ascorbate, urate, alpha-tocopherol, or protein carbonyls. However, in multiple linear regression analyses, the type of home heating (glass-fronted fires or oil-fired central heating) was found to influence ascorbate and urate concentrations in the BAL fluid (ss-coefficient for ascorbate: 0.445, p = 0.031; for urate: 0.114, p = 0.001). There was no significant difference between the N and NA group in BAL fluid concentrations of ascorbate, urate, or protein carbonyls. The alpha-tocopherol concentration was significantly increased in the NA group (p = 0.037). Uric acid and alpha-tocopherol concentrations in BAL fluid and serum were not correlated. Intriguingly, serum and BAL ascorbate concentrations were significantly correlated (r = 0.297, p = 0.018, n = 63), which may offer an explanation for why supplementing the diet with vitamin C can improve asthma symptoms. Further studies will investigate the role of BAL antioxidant concentrations in children with inflammatory respiratory diseases.

Chronic cough in children: bronchoalveolar lavage findings

Isolated chronic cough in childhood is a common complaint. Although the symptom cough is included in the definition of clildhood asthma, there is debate as to whether the majoritv of these children have asthma. The authors studied children with isolated chronic cough looking for evidence of airway inflammation typical of asthma, with increased numbers of airway eosinophils as assessed from bronchoalveolar lavage (BAL). The investigations were carried out on 23 children (median age: 6.7 yrs; range: 1.7-12.75 yrs), attending the Royal Belfast Hospital for Sick Children for elective surgery, who also had a chronic unexplained cough. Written informed consent was obtained from the parent(s) and a nonbronchoscopic BAL was performed. BAL samples were analysed for total and differential white cell counts and also for the inflammatory mediators, eosinophil cationic protein (ECP) and histamine. Results were compared with a group of normal nonatopic children and also a group of atopic asthmatic children, who had been recruited for other studies on airway inflammation. There was a small but statistically significant increase in BAL percentage eosinophils in the children with chronic cough compared with nonasthmatic controls (0.28% versus 0.10%, p=0.03). However, the children with cough had lower percentage eosinophils than the atopic asthmatic controls (0.28% versus 0.66%, p=0.01). Three out of 23 children with chronic cough had BAL eosinophils greater than the normal upper 95% reference interval in BAL. There was a small but statistically significant increase in percentage neutrophils in the children with cough compared with the nonasthmatic controls (5.85% versus 3.21%, p=0.03). Four out of the 23 children had BAL neutrophils greater than the normal upper 95% reference interval in BAL. The authors conclude that only a minority of children with chronic unexplained cough have asthmatic-type airway inflammation. It is speculated that the increased percentage neutrophils in bronchoalveolar lavage from children with cough could relate to underlying persistent airways infection.

Comparison between creatine kinase brain isoenzyme (CKBB) activity and Sarnat score for prediction of adverse outcome following perinatal asphyxia

AIM

To assess whether plasma creatine kinase brain isoenzyme (CKBB) levels or Sarnat scores are more accurate for prediction of poor neurological outcome in babies with suspected birth asphyxia.

METHODS

In a retrospective study of 97 babies CKBB levels were compared to the presence of severe hypoxic ischaemic encephalopathy (HIE) as a predictive test for these outcomes: developmental delay, cerebral palsy, visual problems, deafness or death from perinatal asphyxia. The tests were compared using positive predictive values (PPV) and likelihood ratios (LR) with confidence intervals (CI).

RESULTS

3 babies had died from perinatal asphyxia and 14 survivors were found to have neurological or developmental problems. CKBB was elevated in babies with severe HIE (p = 0.0004). A receiver operator characteristic (ROC) curve showed the optimal discriminating value for CKBB to be 21 IU/L but the CKBB was a poor predictive test. For prediction of adverse outcome: CKBB > 21 sensitivity 76%, specificity 40%, PPV 21% and LR 1.3 (95% CI 0.8-1.7). Severe HIE sensitivity 53%, specificity 95%, PPV 69% and LR 10.6 (95% CI 3.8-29.2).

CONCLUSION

CKBB is elevated following birth asphyxia but is a poor predictor of adverse neurological outcome.

Serum eosinophil cationic protein (ECP): reference values in healthy nonatopic children

BACKGROUND

Although serum ECP concentrations have been reported in normal children, there are currently no published upper cutoff reference limits for serum ECP in normal, nonatopic, nonasthmatic children aged 1-15 years.

METHODS

We recruited 123 nonatopic, nonasthmatic normal children attending the Royal Belfast Hospital for Sick Children for elective surgery and measured serum ECP concentrations. The effects of age and exposure to environmental tobacco smoke (ETS) on the upper reference limits were studied by multiple regression and fractional polynomials.

RESULTS

The median serum ECP concentration was 6.5 microg/l and the 95th and 97.5 th percentiles were 18.8 and 19.9 microg/l. The median and 95th percentile did not vary with age. Exposure to ETS was not associated with altered serum ECP concentrations (P = 0.14).

CONCLUSIONS

The 95th and 97.5 th percentiles for serum ECP for normal, nonatopic, nonasthmatic children (aged 1-15 years) were 19 and 20 microg/l, respectively. Age and exposure to parental ETS did not significantly alter serum ECP concentrations or the normal upper reference limits. Our data provide cutoff upper reference limits for normal children for use of serum ECP in a clinical or research setting.

Serum eosinophilic cationic protein and blood eosinophil counts for the prediction of the presence of airways inflammation in children with wheezing

BACKGROUND

Serum eosinophilic cationic protein (ECP) concentrations may be useful noninvasive markers of airways inflammation in atopic asthma. However, the usefulness of serum ECP measurement for the prediction of airways inflammation in children with a history of wheezing is unknown.

OBJECTIVE

To determine the test accuracy of serum ECP and blood eosinophil percentage as noninvasive markers of eosinophilic airways inflammation.

METHODS

Bronchoalveolar lavage (BAL) fluid and peripheral blood samples for eosinophil percentages and serum ECP were obtained from children undergoing elective surgery and who gave a history of wheezing in the previous year. Sensitivity, specificity and likelihood ratios (LH) and the area under the curve (AUC) for the receiver operator characteristic (ROC) curve were calculated for each blood marker for the prediction of airways inflammation defined by a BAL eosinophil percentage > 0.86. Data were analysed on the basis of how recently symptoms had occurred.

RESULTS

Seventy-seven children (median age 6.75 years) were studied. An AUC of 0.75 (log serum ECP concentration) and 0.76 (log blood eosinophil percentage) was obtained for predicting airways inflammation. A serum ECP > 13 microg/L yielded a LH of 4.4, whereas using a cutoff blood eosinophils > 4% yielded a LH of 1.9, for the prediction of elevated eosinophils in BAL. Serum ECP and eosinophil percentages in BAL and blood were lowest (not statistically significant) when last symptoms had occurred more than 12 weeks previously.

CONCLUSIONS

Serum ECP and blood eosinophil percentages are useful markers for predicting eosinophilic airways inflammation in wheezing children.

Investigation of seroprevalence of respiratory virus infections in an infant population with a multiantigen fluorescence immunoassay using heel-prick blood samples collected on filter paper

Respiratory viruses are an extremely common cause of childhood morbidity. However, the current seroprevalence of viruses in infant populations is difficult to establish because invasive venipuncture may be technically and ethically unacceptable. This prospective study aimed to establish the seroprevalence of respiratory viruses in an infant population by use of a novel multiantigen fluorescence immunoassay against common respiratory viruses, using heel-prick blood samples collected on filter paper. Mothers and babies were recruited in the immediate peripartum period in the Royal Maternity Hospital, Belfast. Cord blood samples at birth and heel-prick filter paper blood samples at 7 mo were collected for measurement of virus-specific IgG to respiratory syncytial virus, influenza A virus, adenovirus, and parainfluenza virus type 1, type 2, and type 3 by indirect immunofluorescence using a multiviral assay developed for this purpose. Of 386 mothers approached, 325 (84%) permitted follow-up at 7 mo, and of these, 256 (79%) agreed to the heel prick. From 234 paired samples, 125 infections were documented. Adenovirus infections were commonest, 53 (22.6%), followed by respiratory syncytial virus, 32 (13.7%); influenza A virus, 22 (9.4%); parainfluenza virus type 3, 14 (6%); parainfluenza virus type 1, 2 (0.85%); and parainfluenza virus type 2, 2 (0.85%). These results demonstrate the seroprevalence of a range of respiratory viruses in an infant population, using a novel multiviral immunoassay. The filter paper collection of blood samples and multiantigen assay format has implications for easy, widespread viral serodiagnosis in both seroepidemiology studies and in the diagnosis of pediatric viral illnesses. Filter paper permits recovery of respiratory virus-specific IgG and can be used as a simple and acceptable epidemiologic and diagnostic tool.

Inflammatory mediators in bronchoalveolar lavage samples from children with and without asthma

BACKGROUND

We investigated whether eosinophils and mast cells, found in the airways of children with wheeze, were activated during relatively asymptomatic periods.

METHODS

A nonbronchoscopic bronchoalveolar lavage (BAL) procedure was performed on children presenting for an elective surgical procedure. Eosinophil-derived (eosinophil cationic protein, ECP) and mast cell-derived (histamine/tryptase) mediator concentrations were measured in the BAL fluid. A detailed history and serum immunoglobulin E were used to classify the children into four groups: atopic with and without asthma, viral-associated wheeze and normal controls.

RESULTS

The ECP concentrations in BAL from atopic asthmatic subjects were significantly higher than those measured in BAL from normal controls (P < 0.01), no other groups differed significantly. Histamine concentrations were elevated in both the atopic asthmatic and viral-associated wheeze groups compared with controls (P < 0.02) and additionally higher concentrations were obtained in atopics with asthma compared with atopics without asthma (P < 0.03). Tryptase concentrations did not differ between groups, although the tryptase and histamine concentrations correlated significantly (r = 0.78, P < 0.0001).

CONCLUSIONS

Elevated histamine concentrations were found in children with wheeze regardless of the aetiology, whereas ECP was only elevated in those asthmatics with atopy. This suggests that even in relatively quiescent periods, there is some on going activation of airway eosinophils in children with atopic asthma.

Bronchoalveolar lavage findings suggest two different forms of childhood asthma

BACKGROUND

It seems plausible that children with atopy and persistent asthma symptoms will, like their adult counterparts, have chronic airways inflammation. However, many young children with no other atopic features have episodic wheezing that is triggered solely by viral respiratory infections. Little is known as to whether airways inflammation occurs in these two asthma patterns during relatively asymptomatic periods.

METHODS

Using a non-bronchoscopic bronchoalveolar lavage (BAL) procedure on children presenting for an elective surgical procedure, this study has investigated the cellular constituents of BAL fluid in children with a history of atopic asthma (AA) non-asthmatic atopic children (NAA) or viral associated wheeze (VAW).

RESULTS

A total of 95 children was studied: 52 with atopic asthma (8.0 years, range 1.1-15.3, 36 male), 23 with non-asthmatic atopy (median age 8.3 years, range 1.7-13.6, 11 male) and 20 with VAW (3.1 years, range 1.0-8.2, 13 male). No complications were observed during the lavage procedure and no adverse events were noted post-operatively. Total lavage fluid recovered was similar in all groups and the total cell numbers were higher in the VAW group. Eosinophil (P < or = 0.005) and mast cell (P < or = 0.05) numbers were significantly elevated in the group with atopic asthma.

CONCLUSIONS

During relatively asymptomatic periods there is on-going airways inflammation, as demonstrated by eosinophil and mast cell recruitment, in children with asthma and atopy but not in children with viral associated wheeze or atopy alone. This strongly suggests that there are different underlying pathophysiological mechanisms in these two groups of children who wheeze.

Evaluation of Ames DCA 2000 for the rapid measurement of HbA1c in an outpatient clinic

Comparison of the Ames DCA 2000, a new device for the rapid measurement of HbA1c, with the established laboratory method (Dako HbA1c system) was made in 58 children routinely attending a diabetic outpatient clinic. Results showed that DCA 2000 and laboratory estimations of HbA1c were closely correlated throughout the range of values (R = 0.95). The mean difference between values was 1.83% with a 95% range of agreement of 0.23-3.4%. The DCA 2000 can be used to provide a rapid estimate of HbA1c upon which decisions on changes in treatment can be based at diabetic clinics.

Growth and adrenal suppression in asthmatic children treated with high-dose fluticasone propionate

BACKGROUND

Fluticasone propionate was introduced in 1993 in the UK as a potentially safer inhaled corticosteroid than those already in use. The efficacy and safety of fluticasone has been established at recommended doses of 200 micrograms/day, but not at higher doses that are often used.

METHODS

Growth retardation was observed in six severely asthmatic children after introduction of high-dose fluticasone propionate treatment (dry powder). Assessment of cortisol response was by insulin-induced hypoglycaemia in three cases, by short tetracosactrin test in two, and by low-dose tetracosactrin and 24-hour urinary cortisol/creatinine ratio in one.

FINDINGS

Six children with growth retardation noted after treatment with high-dose fluticasone propionate were found to have adrenal suppression. In one case the growth rate and cortisol response returned to normal 9 months after the fluticasone dose was reduced to 500 micrograms/day.

INTERPRETATION

When high doses of fluticasone propionate are used, growth may be retarded and adrenal suppression may occur.

Investigating paediatric airways by non-bronchoscopic lavage: normal cellular data

BACKGROUND

Bronchoscopic bronchoalveolar lavage in children to investigate bronchial disorders such as asthma has both ethical and procedural difficulties.

OBJECTIVE

The aim of this study was to establish a standardized non-bronchoscopic method to perform bronchoalveolar lavage in children attending for elective surgery to obtain normal cellular data.

METHODS

Bronchoalveolar lavage was performed on normal children (n = 55) by infusing saline (20 mL) through an 8 FG suction catheter passed after endotracheal intubation. Oxygen saturation, heart and respiratory rate were monitored during the bronchoalveolar lavage procedure. Cellular analysis and total protein estimation of the lavage fluid were performed. Epithelial lining fluid volume was calculated (n = 15) using the urea dilution method.

RESULTS

The procedure was well tolerated by all children. Total cell count and differential cell count for children (macrophages 70.8 +/- 2.3%, lymphocytes 3.8 +/- 0.6%, neutrophils 5.7 +/- 1.0%, eosinophils 0.14 +/- 0.03%, epithelial cells 19.6 +/- 2.1%, mast cells 0.21 +/- 0.02%) were similar to those reported for adults. Age and sex comparisons revealed no differences between groups. The mean total protein recovered in the cell free supernatant was 49.72 +/- 4.29 mg/L and epithelial lining fluid volume was 0.82 +/- 0.11% of return lavageate.

CONCLUSION

This method allows bronchoalveolar lavage to be performed safely and quickly on children attending for routine elective surgery. Using this method and taking the 'window of opportunity' of elective surgery, the presence or absence of airway inflammation could be studied in children with various patterns of asthma during relatively asymptomatic periods.

Linear growth of very young asthmatic children treated with high-dose nebulized budesonide

The aim of this open study was to observe linear growth in young children with asthma treated with nebulized budesonide. Infants and young children (< 3 years old) with severe uncontrolled asthma were studied. They were treated with nebulized budesonide (1-4 mg day-1) and treated for at least 6 months. Height standard deviation scores (HtSDS) were measured before ("pre-measurements") immediately prior to commencing nebulized budesonide therapy (baseline) and after at least 6 months of therapy ("post-measurements"). The mean HtSDS score at pretreatment was -0.21 and at baseline had fallen further to -0.46. The mean HtSDS increased to -0.17 when the post-measurements were made (p = 0.035) after at least 6 months of nebulized budesonide therapy. Treatment with nebulized budesonide for longer than 6 months in very young children with severe asthma was not associated with reduced linear growth.

Managing meningitis in children: audit of notifications, rifampicin chemoprophylaxis, and audiological referrals

Important aspects of the management of meningitis in children include notification to local officers for control of communicable diseases; chemoprophylaxis for index cases and close contacts in cases of meningococcal or Haemophilus influenzae meningitis; and a formal hearing assessment for all survivors. A retrospective audit of these aspects of management was carried out for children admitted with meningitis in 12 months from 1 September 1990 to 31 August 1991 at the Royal Belfast Hospital for Sick Children. Only 20 of 36(56%) cases were notified by medical staff. Chemoprophylaxis was arranged for all close family contacts but to only five of the 23(22%) index cases for whom it was indicated. Appointments for audiological testing were arranged for only 19 of the 32(59%) survivors. Subsequently all doctors, including each intake of junior doctors, were given written information on the importance of notification and locally agreed guidelines for chemoprophylaxis and hearing assessments for survivors before discharge. Guidelines were also displayed prominently in each ward. A repeat audit from January 1992 to December 1992 showed significant improvement in these aspects of care. Twenty eight of 32 cases (88%) were notified, chemoprophylaxis was given to 20 of 22(91%) index cases for whom it was indicated, and 25 of 29(86%) survivors had hearing assessments arranged before discharge. Correct management of some aspects of care cannot be assumed, even if statutory (notification), nationally agreed (chemoprophylaxis), or generally agreed good practice (hearing assessments). These aspects of care improved after the first audit but the authors conclude that the notification rate remains below 100% and a repeat audit is necessary.