Definition, assessment and treatment of wheezing disorders in preschool children: an evidence-based approach

Management of severe asthma in children

Children who are referred to specialist care with asthma that does not respond to treatment (problematic severe asthma) are a heterogeneous group, with substantial morbidity. The evidence base for management is sparse, and is mostly based on data from studies in children with mild and moderate asthma and on extrapolation of data from studies in adults with severe asthma. In many children with severe asthma, the diagnosis is wrong or adherence to treatment is poor. The first step is a detailed diagnostic assessment to exclude an alternative diagnosis ("not asthma at all"), followed by a multidisciplinary approach to exclude comorbidities ("asthma plus") and to assess whether the child has difficult asthma (improves when the basic management needs, such as adherence and inhaler technique, are corrected) or true, therapy-resistant asthma (still symptomatic even when the basic management needs are resolved). In particular, environmental causes of secondary steroid resistance should be identified. An individualised treatment plan should be devised depending on the clinical and pathophysiological characterisation. Licensed therapeutic approaches include high-dose inhaled steroids, the Symbicort maintenance and reliever (SMART) regimen (with budesonide and formoterol fumarate), and anti-IgE therapy. Unlicensed treatments include methotrexate, azathioprine, ciclosporin, and subcutaneous terbutaline infusions. Paediatric data are needed on cytokine-specific monoclonal antibody therapies and bronchial thermoplasty. However, despite the interest in innovative approaches, getting the basics right in children with apparently severe asthma will remain the foundation of management for the foreseeable future.

Paediatric asthma: everything that seemed to be certain no longer is

'Paediatric asthma: everything that seemed to be certain no longer is', holds the promise of leaving you with more questions than answers at the end of this review of paediatric asthma 2008-2009. This has often been true for asthma research, in particular over the past few years. Research with direct consequences for a clinician managing children with wheezing or asthma is discussed such as limitations in the characterisation of asthma phenotypes and the influence of early viral infections on asthma and the development of atopic sensitisation. It appears that wheezing in preschool children with specific viral pathogens confers differential rates of asthma risk. Viruses and day-care shift respiratory morbidity to an early age when it is more troublesome than at a later age but are not protective for sensitisation or asthma. What needs to be further explored is the relationship between viruses and recurrent wheeze or asthma in studies with stringently defined phenotypes including personal atopic status, timing of infection, and severity of infection. A modification of preschool wheeze phenotypes or replacement by other phenotypes that have been defined with the application of different methods is needed. Oral corticosteroids should not be prescribed in preschool children with acute mild to moderate viral wheeze, unless a severe outcome is anticipated or if the child has a classic atopic phenotype. Despite initial high expectations, FeNO was proven not to be beneficial for routine monitoring of asthma treatment.

Clinical findings associated with abnormal lung function in children aged 3-26 months with recurrent respiratory symptoms

AIM

To evaluate whether there are any associations between parentally reported symptoms, clinical findings and lung function in young children with recurrent lower respiratory tract symptoms.

METHODS

In 2000-2003, 148 children, aged 3-26 months, with recurrent lower respiratory tract symptoms underwent physical examination, investigation of a chest radiograph, whole body plethysmography and skin prick testing to common food and inhalant allergens.

RESULTS

Lung function was considered abnormal (i.e. functional residual capacity z-score of > or =1.65 and/or specific conductance z-score of < or =-1.65) in 83 (56%) children. Findings of increased work of breathing (p < 0.001) and nonspecific noisy breathing sounds (p < 0.001) in the physical examination, as well as an abnormal chest radiograph (p = 0.028) were independently associated with abnormal lung function, explaining up to 34% of the variation in lung function. In contrast, parentally reported respiratory symptoms, environmental exposures or atopic trait were not associated with lung function abnormalities.

CONCLUSION

The results of this study emphasize the importance of the meticulous clinical examination in the evaluation of early childhood respiratory disorders. As physical examination alone cannot predict lung function abnormalities reliably in preschool children with troublesome respiratory symptoms, lung function testing may be considered in such patients to obtain additional objective information.

Recent advances in pediatric asthma treatment

Although wheezing illness is at its most prevalent in infancy and early childhood, its self-limiting nature in the majority poses considerable challenges in offering a long-term prognosis and in initiating long-term prophylaxis. Many of the established treatments in adults have not been adequately assessed in children. Evidence is also emerging for a number of different wheezing syndromes, several of which do not to respond well to currently available medicines. Much research interest is being directed to underlying changes within the airway that appear to be independent of allergic mechanisms and that may lead to novel therapeutic approaches. The aim of this review is to restate and update current best-practice based on evidence, to encourage effective and safe use of asthma medication in children and to point to areas of ongoing research that are likely to influence management decisions in the near future.

Sputum dipalmitoylphosphatidylcholine level as a novel airway inflammatory marker in asthmatic children

INTRODUCTION

Pulmonary surfactant is a unique mixture of lipids and surfactant-specific proteins. Phosphatidylcholine comprises almost 80% of the total surfactant lipids, about half of which is dipalmitoylphosphatidylcholine (DPPC). Alteration of surfactant composition and function is documented with various airway or lung parenchyma disorders.

OBJECTIVE

To assess sputum concentration of DPPC as a major component of airways surfactant in asthmatic children compared to conventional airway inflammatory markers.

METHODS

This case control study included 68 well-known asthmatic children of different grades of severity and 20 age- and sex-matched normal children as controls. All children were subjected to thorough clinical examination, pulmonary function tests, sputum induction and processing for cytology, DPPC level and eosinophil cationic protein (ECP) level assessment.

RESULTS

Elevated DPPC levels were evident in all sputum samples of asthmatic children (mean value 626.6 +/- 189.7 mcg/mL) compared to controls (mean value 49.3 +/- 20.1 mcg/mL). Significant negative correlations (r = -0.83, -0.752 and -0.384) were found between asthmatics sputum DPPC levels and pulmonary function test parameters [% of forced expiratory volume in first second, % of forced vital capacity (FVC) and forced expiratory flow rate over 25%-75% part of FVC], respectively. Meanwhile, significant positive correlations were evident between asthmatics sputum DPPC levels and the sputum inflammatory cells and their sputum ECP levels.

CONCLUSION

Elevated DPPC levels are evident in induced sputum of all asthmatic children and they are significantly related to sputum ECP levels and pulmonary function test parameters. Nevertheless, the value of DPPC estimation in the clinical management of children with asthma remains to be determined.

Montelukast in the treatment of asthma and beyond

Asthma is a chronic inflammatory disease affecting over 300 million people worldwide. The common association with allergic rhinitis and the presence of proinflammatory cells and mediators in the circulation of patients qualify asthma as a systemic disease. This characteristic and the fact that the gold-standard therapy for persistent asthma, inhaled corticosteroids, cannot suppress all components of airway inflammation and fail to adequately penetrate into the small airways, warrant the quest for effective systemic anti-asthma therapies. This review describes the most important controlled studies of montelukast, a once-daily leukotriene receptor antagonist, in asthma and allergic rhinitis in both adults and children. Montelukast is a systemically active drug with a targeted, dual mechanism of action, acting both as a bronchodilator and anti-inflammatory. In patients of all ages, montelukast has shown a favorable safety profile and was well-tolerated. Both as monotherapy or in combination with inhaled corticosteroids, montelukast produced clinically relevant improvements in asthma-related parameters, including symptoms, lung function parameters, quality of life and the number of asthma exacerbations. Furthermore, bronchoprotective effects have been reported both against specific and nonspecific bronchoactive stimuli. Similarly, in patients with allergic rhinitis, montelukast produced substantial improvements in symptoms and quality of life. Long-term studies aimed to determine its effects on airway remodeling are still lacking.

Current concepts on the use of glucocorticosteroids and beta-2-adrenoreceptor agonists to treat childhood asthma

PURPOSE OF REVIEW

This article reviews current concepts regarding the clinical and scientific rationale for the combined use of glucocorticosteroids and beta-2-adrenoreceptor (beta2AR) agonists in the treatment of childhood asthma.

RECENT FINDINGS

Several studies have demonstrated that inhaled corticosteroids (ICS) and beta2AR agonists are the most effective medications for the management of asthma in children. Given substantial evidence of an increased clinical benefit when these agents are used together, new studies are being pursued to establish the efficacy and safety of this combinational therapy in infants and children. Ongoing research is also investigating the mechanisms of beta2AR and glucocorticosteroids signaling and their molecular interactions. This new knowledge will likely lead to novel therapeutic approaches to asthma control.

SUMMARY

There is increasing evidence demonstrating that the combination of long-acting beta2AR agonists and ICS may be more effective than high-dose ICS therapy alone in the management of children with uncontrolled asthma. In addition, the use of a single inhaler containing ICS and a quick-acting beta2AR agonist might be a convenient alternative to prevent and treat asthma exacerbations. Future investigations should be designed to more specifically evaluate the efficacy and safety of these therapies in the different asthmatic phenotypes of infants and children.

Viruses and atypical bacteria associated with asthma exacerbations in hospitalized children

OBJECTIVES AND WORKING HYPOTHESIS: To evaluate the prevalence of respiratory viruses Mycoplasma pneumoniae and Chlamydophila pneumoniae and gain insight into their seasonal circulation pattern in children with acute asthma exacerbations in a temperate southern hemisphere region.

STUDY DESIGN

Patients hospitalized between 3 months and 16 years of age were included in a 1-year prospective, observational, cross-sectional study. Respiratory secretions were collected and the presence of different viruses and atypical bacteria analyzed by immunofluorescence and polymerase chain reaction.

RESULTS

Two hundred nine patients (118 females) aged (mean +/- SD) 4.4 +/- 4 years were included. A potential causative agent was detected in 78% of the patients. The most frequently detected viruses were respiratory syncytial virus (HRSV) (n = 85; 40%) and rhinovirus (HRV) (n = 52; 24.5%); M. pneumoniae and C. pneumoniae were detected in 4.5% and 2% of the cases, respectively. Patients with HRSV (vs. HRV) were hospitalized for a longer time (6.7 vs. 5.2 days, P = 0.012), required more days of oxygen supply (5.1 vs. 3.4, P = 0.005), had a longer duration of the exacerbation before hospitalization (3.6 vs. 1.9 days, P = 0.001) and were younger (3.7 vs. 5.1 years, P = 0.012). Three peaks of admissions were observed. A first peak (early autumn) caused by HRV, a second peak (winter) caused mainly by HRSV and a third one (spring), caused by HRSV, an increase in HMPV together with a second outbreak of HRV.

CONCLUSIONS

Children with an acute asthma exacerbation presented a high prevalence of respiratory viruses. Most hospitalizations corresponded to seasonal increases in prevalence of HRV and HRSV.

A comparison of parent-reported wheezing or shortness of breath among infants as assessed by questionnaire and physician-interview: The Generation R study

PURPOSE

The prevalence of asthma symptoms among preschool children is difficult to determine with accuracy because no gold standard is available for diagnosis. The aim of this study was to compare parent-reported wheezing or shortness of breath among infants as assessed by questionnaire and physician-interview.

METHODS

We studied 1,202 children participating in the Generation R study. Their parents completed a written questionnaire at home when the infant was 12 months old, including items on wheezing or shortness of breath. During the regular free-of-charge youth healthcare visit at age 14 months, the physician interviewed the parents to assess the presence of wheezing or shortness of breath.

RESULTS

The prevalence of wheezing or shortness of breath estimated from questionnaire was significantly higher than from physician-interview (36% vs. 20%; P < 0.001): observed agreement 73% (kappa 0.36). Only 41% of questionnaire-reported symptoms were assessed through the physician-interview, while 73% of physician-interviewed symptoms were reported in the questionnaire. Compared with infants in the subgroup with agreement on the presence of wheezing or shortness of breath, the infants in the subgroups without agreement significantly less often received anti-asthma medication and significantly less often had abnormal respiratory sounds or bronchiolitis or croup, and their mothers were significantly less often working. The proportion of infants receiving anti-asthma medication was higher in interview-data compared with questionnaire-data (22.7% vs. 3.9%; P < 0.001).

CONCLUSIONS

Questionnaire yielded higher prevalence rates for wheezing or shortness of breath than physician-interview. Physician-reported symptoms are associated with a higher proportion of infants receiving anti-asthma medication. Parent-reported asthma symptoms should be confirmed by pediatricians whenever possible.

[Consensus conference on acute bronchiolitis (v): prevention of acute bronchiolitis. Review of scientific evidence]

A review of the evidence on prevention of acute bronchiolitis is presented. Acute bronchiolitis prevention arises from three basic approaches: preventive treatment to reduce recurrent wheezing following an episode of acute bronchiolitis, preventive treatment to reduce the frequency and severity of RSV bronchiolitis in the population at risk (prematurity, bronchopulmonary dysplasia, congenital heart disease, etc.), and general preventive measures to reduce nosocomial infection with RSV. There is sufficient evidence on the lack of efficacy of inhaled corticosteroids, oral corticosteroids and montelukast. Intravenous RSV immunoglobulin has an unfavorable risk-benefit balance, particularly with the availability of monoclonal antibodies. Palivizumab is effective as preventive treatment of RSV infection in risk populations (high risk preterm infants and hemodynamically significant congenital heart disease), but not in the frequency and severity (ICU admission, need for mechanical ventilation and mortality) of the acute bronchiolitis. The benefits of palivizumab (less admissions) seem to be worth the adverse effects, but we do not know the cost-benefit ratio. The control and prevention measures of nosocomial transmission of RSV infection (isolation, hand washing, use of mask, gloves, cap and shoes) are based on indirect evidence.

Asthma therapy during the first 8 years of life: a PIAMA cohort study

OBJECTIVE

Many studies evaluated asthma medication use in children in a cross-sectional manner, yet little is known about longitudinal use patterns. This study describes the formation of a longitudinal data set on asthma medication use and shows first results regarding the prevalence and incidence of medication use.

METHODS

The PIAMA (Prevention and Incidence of Asthma and Mite Allergy) study is a prospective birth cohort study among 3963 Dutch children. Recruitment took place in 1996-1997. The data of the PIAMA birth cohort study were complemented with pharmacy data. Prescription information of family members was used to determine whether medication histories were complete from birth until age 8. The prevalence and incidence of asthma medication use was studied in children for whom complete medication histories were available.

RESULTS

A first prescription for asthma medication was filled before age 8 by 280 (36%) children, with 88% starting therapy before age 5. Of all children who started therapy, 91.1% received short-acting beta(2)-agonists and 61.1% inhaled corticosteroids.

CONCLUSION

The applied method of data collection rendered a data set including 777 children with complete medication histories for their first 8 years of life. This data set provides the opportunity to study longitudinal medication use patterns. First analyses show that asthma medication is initiated in a rather high percentage of children in this cohort and mainly at an age at which an asthma diagnosis cannot yet be firmly established.

In-label and off-label use of respiratory drugs in the Italian paediatric population

AIM

To evaluate the prescription rate of respiratory drugs (ATC code R03) in an Italian community setting and to estimate the extent of off-label use by both age and indication.

METHODS

A cohort study aimed at evaluating prescriptions of drugs with ATC code R03 was conducted for the period 2002-2006. Data source was the PEDIANET Database.

RESULTS

Ninety percent of R03 prescriptions are covered by 11 active substances or combinations, corresponding to 67 medicinal products. Inhaled corticosteroids are the most prescribed anti-asthmatic agents, followed by short-acting beta2 mimetics. The mean off-label rate is 19 and 56%, by age and indication respectively. The majority of off-label uses is among children under the age of 2. Five active substances are used at dosages not supported by adequate dose-finding studies.

CONCLUSION

In Italy, many respiratory drugs are approved for the treatment of paediatric respiratory diseases, but a remarkable percentage of their prescriptions is off-label. This pharmaco-utilization study demonstrates that there is a need to perform clinical studies aimed at increasing the current knowledge on marketed paediatric drugs, and to revise and re-label the existing regulatory documents to reduce their off-label uses.

Elevated exhaled nitric oxide in high-risk neonates precedes transient early but not persistent wheeze

RATIONALE

Elevated fractional exhaled nitric oxide (Fe(NO)) concentration has been suggested to predict early childhood wheeze and sensitization.

OBJECTIVES

To investigate the association between Fe(NO) in asymptomatic neonates and the development of wheeze patterns and atopic intermediary phenotypes in the first 6 years of life.

METHODS

We measured Fe(NO) in 253 healthy 1-month-old neonates from the Copenhagen Prospective Study on Asthma in Childhood birth cohort and monitored prospectively wheezy episodes by daily diary cards during the first 6 years of life. Total IgE, specific IgE, and blood eosinophil count were assessed at age 6 months, 4 years, and 6 years. Associations were studied by Cox regression, logistic regression, and generalized linear models.

MEASUREMENTS AND MAIN RESULTS

Increased neonatal Fe(NO) level was significantly associated with the development of recurrent wheeze in the first year of life (hazard ratio, 2.63; 95% confidence interval, 1.1 to 6.2; P = 0.026) but not thereafter. The association was unaffected by environmental tobacco smoke exposure. Fe(NO) was not associated with elevated levels of total IgE, specific IgE, or blood eosinophil count at any age point and was unrelated to neonatal lung function.

CONCLUSIONS

An elevated Fe(NO) level in asymptomatic neonates born to mothers with asthma preceded the development of transient early wheezing, but not persistent wheezing during preschool age, and was unrelated to atopy. This suggests an early disease process other than small airway caliber contributing to the transient wheezing phenotype.

Parent initiated prednisolone for acute asthma in children of school age: randomised controlled crossover trial

OBJECTIVE

To evaluate the efficacy of a short course of parent initiated oral prednisolone for acute asthma in children of school age.

DESIGN

Double blind, randomised, placebo controlled, crossover trial in which episodes of asthma, rather than participants, were randomised to treatment.

SETTING

The Barwon region of Victoria, Australia.

PARTICIPANTS

Children aged 5-12 years with a history of recurrent episodes of acute asthma.

INTERVENTION

A short course of parent initiated treatment with prednisolone (1 mg/kg a day) or placebo.

MAIN OUTCOME MEASURES

The primary outcome measure was the mean daytime symptom score over seven days. Secondary outcome measures were mean night time symptom score over seven days, use of health resources, and school absenteeism.

RESULTS

230 children were enrolled in the study. Over a three year period, 131 (57%) of the participants contributed a total of 308 episodes of asthma that required parent initiated treatment: 155 episodes were treated with parent initiated prednisolone and 153 with placebo. The mean daytime symptom score was 15% lower in episodes treated with prednisolone than in those treated with placebo (geometric mean ratio 0.85, 95% CI 0.74 to 0.98; P=0.023). Treatment with prednisolone was also associated with a 16% reduction in the night time symptom score (geometric mean ratio 0.84, 95% CI 0.70 to 1.00; P=0.050), a reduced risk of health resource use (odds ratio 0.54, 95% CI 0.34 to 0.86; P=0.010), and reduced school absenteeism (mean difference -0.4 days, 95% CI -0.8 to 0.0 days; P=0.045).

CONCLUSION

A short course of oral prednisolone initiated by parents when their child experiences an episode of acute asthma may reduce asthma symptoms, health resource use, and school absenteeism. However, the modest benefits of this strategy must be balanced against potential side effects of repeated short courses of an oral corticosteroid.

TRIAL REGISTRATION

ISRCTN 26232583.

Prevalence and risk factors of wheeze in Dutch infants in their first year of life

Factors operating in the first year of life are critical in determining the onset and persistence of wheezing in preschool children. This study was designed to examine the prevalence and risk factors of wheeze in the first year of life in Dutch infants. This was a population-based survey of 13-month-old infants visiting well baby clinics for a scheduled immunization. Parents/caregivers completed a standardized validated questionnaire on respiratory symptoms in the first year of life and putative risk factors. The independent influence of these factors for wheeze was assessed by multiple logistic regression analysis. A total of 1,115 questionnaires were completed. Wheeze ever (with a prevalence in the first year of life of 28.5%) was independently associated with male gender, eczema, sibs with asthma, any allergic disease in the family, day care, damp housing, and asphyxia. Recurrent wheeze (prevalence 14.5%) showed independent associations with eczema, sibs with asthma, and day care. In addition to these factors, severe wheeze (prevalence 15.4%) was also associated with premature rupture of membranes during birth, and with damp housing. Wheeze is common during the first year of life, and places a major burden on families and the health care system. Factors associated with wheeze are mainly related to markers of atopic susceptibility, and to exposure to infections. The strongest modifiable risk factor for wheeze in the first year of life is home dampness. Interventions to reduce home dampness to reduce wheeze in infancy should be examined.

[News in childhood asthma therapy]

Research in the field of paediatric pulmonology, especially asthmology, has been intensified for the last couple of years. A large number of studies describe early wheezing episodes, risk factors, natural course of early childhood asthma. Besides this, literature shows a growing interest in epidemiology, genetics and virusology as predictive factors for development and clinical course of childhood asthma. In this paper, the authors are providing a review of recently published articles on asthma therapy based on phenotypes in terms of better understanding of asthma and asthma-like syndromes. Paediatric respiratory experts worldwide are equally positive in the following statements: real diagnosis leads to real therapy as soon as possible; inhaled corticosteroids are not recommended in very young infants especially if a positive effect is missing; long-term therapy with inhaled corticosteroids has to be scrutinized.

Respiratory viral infections in infants: causes, clinical symptoms, virology, and immunology

In global terms, respiratory viral infection is a major cause of morbidity and mortality. Infancy, in particular, is a time of increased disease susceptibility and severity. Early-life viral infection causes acute illness and can be associated with the development of wheezing and asthma in later life. The most commonly detected viruses are respiratory syncytial virus (RSV), rhinovirus (RV), and influenza virus. In this review we explore the complete picture from epidemiology and virology to clinical impact and immunology. Three striking aspects emerge. The first is the degree of similarity: although the infecting viruses are all different, the clinical outcome, viral evasion strategies, immune response, and long-term sequelae share many common features. The second is the interplay between the infant immune system and viral infection: the immaturity of the infant immune system alters the outcome of viral infection, but at the same time, viral infection shapes the development of the infant immune system and its future responses. Finally, both the virus and the immune response contribute to damage to the lungs and subsequent disease, and therefore, any prevention or treatment needs to address both of these factors.

The transient value of classifying preschool wheeze into episodic viral wheeze and multiple trigger wheeze

BACKGROUND

A recently proposed method for classifying preschool wheeze is to describe it as either episodic (viral) wheeze or multiple trigger wheeze. In research studies, phenotype is generally determined by retrospective questionnaire.

AIM

To determine whether recently proposed phenotypes of preschool wheeze are stable over time.

METHODS

In all, 132 two to six-year-old children with doctor diagnosed asthma on maintenance inhaled corticosteroids were classified as having episodic (viral) wheeze or multiple trigger wheeze at a screening visit and then followed up at three-monthly intervals for a year. At each follow-up visit, standardized questionnaires were used to determine whether the subjects wheezed only with, or also in the absence of colds. Stability of the phenotypes was assessed at the end of the study.

RESULTS

Phenotype as determined by retrospective parental report at the start of the study was not predictive of phenotype during the study year. Phenotypic classification remained the same in 45.9% of children and altered in 54.1% of children.

CONCLUSION

When children with preschool wheeze are classified into episodic (viral) wheeze or multiple trigger wheeze based on retrospective questionnaire, the classification is likely to change significantly within a 1-year period.

Asma infantil y del lactante

El asma es la enfermedad crónica más frecuente de la infancia. El diagnóstico suele ser fácil cuando se producen episodios de disnea espiratoria con sibilancias reversibles de forma espontánea o mediante el uso de broncodilatadores. Las radiografías de tórax, la exploración funcional respiratoria y el estudio alérgico constituyen el aspecto fundamental de las pruebas complementarias necesarias. El tratamiento de la crisis consiste en el uso de β2-adrenérgicos inhalados y, si es necesario, corticoides orales. El tratamiento de fondo tiene como objetivo limitar al máximo los síntomas y restaurar o mantener las funciones pulmonares normales. Se debe adaptar a la gravedad y al control de la enfermedad y los corticoides inhalados tienen un papel de elección.

A disease model for wheezing disorders in preschool children based on clinicians' perceptions

BACKGROUND

Wheezing disorders in childhood vary widely in clinical presentation and disease course. During the last years, several ways to classify wheezing children into different disease phenotypes have been proposed and are increasingly used for clinical guidance, but validation of these hypothetical entities is difficult.

METHODOLOGY/PRINCIPAL FINDINGS

The aim of this study was to develop a testable disease model which reflects the full spectrum of wheezing illness in preschool children. We performed a qualitative study among a panel of 7 experienced clinicians from 4 European countries working in primary, secondary and tertiary paediatric care. In a series of questionnaire surveys and structured discussions, we found a general consensus that preschool wheezing disorders consist of several phenotypes, with a great heterogeneity of specific disease concepts between clinicians. Initially, 24 disease entities were described among the 7 physicians. In structured discussions, these could be narrowed down to three entities which were linked to proposed mechanisms: a) allergic wheeze, b) non-allergic wheeze due to structural airway narrowing and c) non-allergic wheeze due to increased immune response to viral infections. This disease model will serve to create an artificial dataset that allows the validation of data-driven multidimensional methods, such as cluster analysis, which have been proposed for identification of wheezing phenotypes in children.

CONCLUSIONS/SIGNIFICANCE

While there appears to be wide agreement among clinicians that wheezing disorders consist of several diseases, there is less agreement regarding their number and nature. A great diversity of disease concepts exist but a unified phenotype classification reflecting underlying disease mechanisms is lacking. We propose a disease model which may help guide future research so that proposed mechanisms are measured at the right time and their role in disease heterogeneity can be studied.

Current guidelines for the management of asthma in young children

The diagnosis and management of asthma in young children is difficult, since there are many different wheezy phenotypes with varying underlying aetiologies and outcomes. This review discusses the different approaches to managing young children with wheezy illnesses presented in recently published global guidelines. Four major guidelines published since 2007 are considered. Helpful approaches are presented to assist the clinician to decide whether a clinical diagnosis of asthma can, or should be made in a young child with a recurrent wheezy illness and which treatments would be appropriate, dependent on risk factors, age of presentation, response to initial treatment and safety considerations. Each of the guidelines provide useful information for clinicians assessing young children with recurrent wheezy illnesses. There are differences in classification of the disease and treatment protocols. Although a firm diagnosis of asthma may only be made retrospectively in some cases and there are several effective guidelines to initiating treatment. Consistent review of the need for ongoing treatment with a particular pharmacological modality is essential, since many children with recurrent wheezing in infancy go into spontaneous remission. It is probable that newer biomarkers of airway inflammation will assist the clinician as to when to initiate and when to continue pharmacological treatment in the future.

The use of inhaled corticosteroid in preschool wheezers: what's the point today?

Among the preschool children who wheeze two different groups can be identify: children who have a viral infection and those who respond to multiple triggers, such as exercise or allergens.

To distinguish between these different phenotypes of wheezing, and consequently choose therapy represents a major challenge for pediatricians.

Transient wheezers conditions do not improve with maintenance treatment with ICS. On the other hand they are definitely useful in children with wheeze/asthma.

Increasing evidence is in favor of the potential role of leukotriene receptor antagonists in preschool children with recurrent wheezing.

Oral steroid has been demonstrated not to be indicated to control acute wheezing, unless severe disease is expected in non-atopic children.

The early phenotyping of preschool wheezers, upon which the appropriate treatment should be based, represents a challenging issue in the paediatric practice.

Anti-inflammatory drug therapy in asthma

Asthma is a disease with chronic inflammation of the airways and and-inflammatory treatment is a logical treatment. Inhaled corticosteroids [ICS] remain the cornerstone of anti-inflammatory therapy in recent international guidelines. Asthma cannot be cured by any medication: if the drug is discontinued, the disease manifestations return. This has been proven at all ages. In preschool children the diagnosis of asthma is difficult to establish. In this heterogeneous group ICS or leukotriene receptor antagonists [LTRA] are just as effective as placebo; in the future it will hopefully be possible to describe characteristics of responders. LTRA are an alternative in mild asthma, especially when mono-triggered viral related wheeze is present. Theophylline is effective and also has bronchodilatory properties, which need to be balanced against the relatively frequent side effects. The working mechanisms of anti-inflammatory asthma medications including ICS, LTRA, cromones, macrolides and theophylline are described.

Chronic respiratory symptoms and diseases among indigenous children

Children from Indigenous populations experience more frequent, severe, and recurrent lower respiratory infections as infants and toddlers. The consequences of these infections are chronic lung disorders manifested by recurrent wheezing and chronic productive cough. These symptoms are aggravated more frequently by active and passive tobacco smoke exposure among Indigenous groups. Therapies for these symptoms, although not specific to children of Indigenous origins, are described as is the evidence for their use.

Recurrent wheezing illness in preschool-aged children: assessment and management in primary care practice

Recurrent wheezing is common in preschool-aged children, with 1 in 3 children experiencing at least 1 acute wheezing illness before the age of 3 years. These children represent a diverse group, with some going on to present with asthma at school age and others experiencing complete resolution of symptoms. The primary care physician is faced with a dilemma of when to recommend daily therapy. He or she must also answer parents' concerns, often expressed as, "Does my child have asthma?" and "Will my child have to take medication the rest of his or her life?" This article presents recent studies and recommendations that can guide the physician in approaching the child and the parent with rational management. The emphasis is on viewing recurrent wheezing as a continuum requiring a plan of monitoring that starts with the very first episode. Using background information from the parents and a history of the child's allergic disposition, one can discuss with parents the risks of developing asthma and, together with planned monitoring, prescribe appropriate management. The primary care physician can plan management by using the Asthma Predictive Index and employing specific questions for features present during the intervals between acute episodes. Together with close monitoring, the physician will have a compass that effectively directs rational management.

Onions, myths, beliefs, fashion and reality in asthma

Some myths and unsupported beliefs about asthma are very popular and enjoy general public acceptance and fairly strong support on the Internet. Onions for cough; dairy products avoidance for asthma; and some other popular myths are reviewed, along with some other medical and mixed (popular and medical) myths comparing their popular and scientific support. Classifying medical statements as realities or unsupported beliefs is a hard and serious work nowadays addressed by Evidence Based Medicine methods, which are not devoid of the influence of medical fashion: the medical community is more prone to accept fashionable statements compared to non-fashionable or old-fashioned statements.

[Incidence of wheezing and associated risk factors in the first 6 months of life of a cohort in Valencia (Spain)]

OBJECTIVES

To determine the incidence of wheezing at 6 months of life in the town of Alzira (Valencia, Spain), and to analyse associated risk factors.

METHODS

We included 636 newborns in a longitudinal birth cohort study between March 2007 and November 2008. Data were collected from hospital and primary care medical records and from questionnaires sent at 6 months post-natal. Bivariate and multivariate Cox regression analysis were performed to examine the risk factors associated with wheezing.

RESULTS

At 6 months, 25.2% of infants had had 1 or more episodes of wheezing, whereas 5.6% had had 3 or more episodes. Emergency visits were reported in 11.6% of the infants, treatment with oral corticosteroids in 6.6% and admission to hospital in 4%. Independent risk factors for wheezing were male sex (relative risk [RR]: 2.1, 95% confidence interval [95% CI]: 1.5 to 2.9), younger gestational age (RR: 1.1, 95% CI: 1.0 to 1.2), season of birth between July and September (RR: 3.5, 95% CI: 2.0 to 5.9) and between October and December (RR: 2.0, 95% CI: 1.1 to 3.6), younger maternal age (RR: 1.0, 95% CI: 1.0 to 1.1), having siblings (RR: 3.1, 95% CI: 2.2 to 4.5), exposure to smoke (RR: 1.4, 95% CI: 12.0 to 2.0) and history of maternal asthma (RR: 1.7, 95% CI: 1.0 to 3.0). Breast feeding for at least 3 months (RR: 0.6, 95% CI: 0.4 to 0.8) and having immigrant parents (RR: 0.6, 95% CI: 0.4 to 0.9) were protective against wheezing.

CONCLUSION

A high cumulative incidence of wheezing in the first 6 months of life was found in our population, in comparison with data reported in other cohort studies. Estimated risk factors were generally in accordance with those described by other authors. Having siblings and season of birth between July and September were the most important risk factors, reflecting the role of viral infections in the pathogenesis of wheezing in early childhood.

[Diagnosis and treatment guidelines for difficult-to-control asthma in children]

Children suffering from difficult-to-control asthma (DCA) require frequent appointments with their physician, complex treatment regimes and often admissions to hospital. Less than 5% of the asthmatic population suffer this condition. DCA must be correctly characterised to rule out false causes of DCA and requires making a differential diagnosis from pathologies that mimic asthma, comorbidity, environmental and psychological factors, and analysing the factors to determine poor treatment compliance. In true DCA cases, inflammation studies (exhaled nitric oxide, induced sputum, broncho-alveolar lavage and bronchial biopsy), pulmonary function and other clinical aspects can classify DCA into different phenotypes which could make therapeutic decision-making easier.

Leukotriene modifiers in the treatment of asthma in children

Asthma is one of the most common respiratory disorders in clinical practice, affecting up to 13% of people worldwide. Inflammation is the most important component of asthma and inhaled corticosteroids (ICS) are recommended as the first line controller treatment for patients of all ages. Treatment with corticosteroids is often unable to fully control asthma symptoms and progression. Recently, leukotrienes have come to the forefront of research as they have been found play a pivotal role in the airway inflammatory process, and specific drugs have been developed to target them. Cysteiny leukotriene antagonists (LTRAs) have recently emerged as important therapeutic options that show a large potential clinical utility. Three specific LTRAs are licensed for clinical use: montelukast, zafirlukast and pranlukast, although montelukast is the only drug approved in the paediatric age range. It is well tolerated (although adverse effects such as headaches, abdominal pain, rashes, angioedema, pulmonary eosinophilia and arthralgia have been reported) and shows many positive effects in asthmatic patients. Current Global Initiative for Asthma guidelines recommend LTRAs as: (1) a second choice treatment to ICS for patients with mild persistent asthma, (2) an add-on therapy to reduce the dose of ICS in patients with moderate or severe asthma, due to the different and complementary mechanisms of action of these agents. LTRAs may be particularly appropriate choices in a number of clinical situations, including the following: patients with concomitant rhinitis; patients with viral-induced wheeze; patients with exercise-induced bronchoconstriction (EIB) and, in children aged 2-5 years, to reduce the frequency of asthma exacerbations.

Regular vs prn nebulized treatment in wheeze preschool children

BACKGROUND

International guidelines recommend regular treatment with inhaled glucocorticoids for children with frequent wheezing; however, prn inhaled bronchodilator alone or in combination with glucocorticoid is also often used in practice. We aimed to evaluate whether regular nebulized glucocorticoid plus a prn bronchodilator or a prn nebulized bronchodilator/glucocorticoid combination is more effective than prn bronchodilator alone in preschool children with frequent wheeze.

METHODS

Double-blind, double-dummy, randomized, parallel-group trial. After a 2-week run-in period, 276 symptomatic children with frequent wheeze, aged 1-4 years, were randomly assigned to three groups for a 3-month nebulized treatment: (1) 400 microg beclomethasone bid plus 2500 microg salbutamol prn; (2) placebo bid plus 800 microg beclomethasone/1600 microg salbutamol combination prn; (3) placebo bid plus 2500 microg salbutamol prn. The percentage of symptom-free days was the primary outcome measure. Secondary outcomes included symptom scores, use of relief medication and exacerbation frequency.

RESULTS

As compared with prn salbutamol (61.0 +/- 24.83 [SD]), the percentage of symptom-free days was higher with regular beclomethasone (69.6%, SD 20.89; P = 0.034) but not with prn combination (64.9%, SD 24.74). Results were no different in children with or without risk factors for developing persistent asthma. The effect of prn combination was no different from that of regular beclomethasone on the primary and on several important secondary outcomes.

CONCLUSIONS

Regular inhaled glucocorticoid is the most effective treatment for frequent wheezing in preschool children. However, prn bronchodilator/glucocorticoid combination might be an alternative option, but it requires further study.

The Saudi Initiative for Asthma

The Saudi Initiative for Asthma (SINA) provides up-to-date guidelines for healthcare workers managing patients with asthma. SINA was developed by a panel of Saudi experts with respectable academic backgrounds and long-standing experience in the field. SINA is founded on the latest available evidence, local literature, and knowledge of the current setting in Saudi Arabia. Emphasis is placed on understanding the epidemiology, pathophysiology, medications, and clinical presentation. SINA elaborates on the development of patient-doctor partnership, self-management, and control of precipitating factors. Approaches to asthma treatment in SINA are based on disease control by the utilization of Asthma Control Test for the initiation and adjustment of asthma treatment. This guideline is established for the treatment of asthma in both children and adults, with special attention to children 5 years and younger. It is expected that the implementation of these guidelines for treating asthma will lead to better asthma control and decrease patient utilization of the health care system.

Emergency presentation and management of acute severe asthma in children

Acute severe asthma is one of the most common medical emergency situations in childhood, and physicians caring for acutely ill children are regularly faced with this condition. In this article we present a summary of the pathophysiology as well as guidelines for the treatment of acute severe asthma in children. The cornerstones of the management of acute asthma in children are rapid administration of oxygen, inhalations with bronchodilators and systemic corticosteroids. Inhaled bronchodilators may include selective b2-agonists, adrenaline and anticholinergics. Additional treatment in selected cases may involve intravenous administration of theophylline, b2-agonists and magnesium sulphate. Both non-invasive and invasive ventilation may be options when medical treatment fails to prevent respiratory failure. It is important that relevant treatment algorithms exist, applicable to all levels of the treatment chain and reflecting local considerations and circumstances.

Cough affects quality of life in asthmatic children aged 8-14 more than other asthma symptoms

BACKGROUND

Asthma may influence children's health-related quality of life (QoL) differently by various symptoms, at different severity. The primary aim of this study was to evaluate the QoL in children with asthma and describe the impact of each asthma symptom on the child's well-being at different severity levels.

MATERIAL AND METHODS

Two hundred randomly selected children and one of their parents who consulted an outpatient asthma clinic, participated in the study. Qol was assessed with DISABKIDS-Smiley measure for children aged 4-7 years and with DISABKIDS DCGM-37 and Asthma Module for children 8-14 year old.

RESULTS

Most of the children suffered from mild or moderate persistent asthma. Children with uncontrolled asthma stated lower QoL compared to partly controlled or controlled in both age groups (p < 0.05 in all domains). Cough appeared to affect QoL of 8-14 year olds more than other symptoms, especially in girls. In younger children, sex (boys, p = 0.039), age (p = 0.045), proxy sex (father, p = 0.048), frequency of doctor visits (4-6 months, p = 0.001), use of beta-2 agonists (p = 0.007) and father's smoking habits (p = 0.015) were associated with the QoL of coughing children but no correlation between cough and QoL was detected. In the 8-14 year age group coughers reported lower QoL compared to their counterparts; moreover, cough was found to affect QoL more than other symptoms (p < 0.05 in all domains).

CONCLUSIONS

Cough has a direct effect on asthmatic children's QoL but there is still an obvious need for research to reveal all the determinats of this effect.

Anti-inflammatory treatment of asthma: differentiation and trial-and-error

The relative lack of evidence for anti-inflammatory treatment of some phenotypes of asthma in children has been highlighted in recent guidelines and consensus reports specifically aiming at the paediatric population. Consequently, we are left with a need for defining treatment strategies in the clinical setting. The decision to initiate antiinflammatory treatment should be based on assessments of the individual child's age, the type of asthma, severity, heredity and atopic condition, adherence factors and sensitivity to systemic adverse effects of treatment options. Inhaled corticosteroids are potent anti-inflammatory agents that are effective in the whole spectrum of asthma in school age children. In toddlers with viral wheeze and in children with mild asthma oral leukotriene receptor antagonists or inhaled corticosteroids may be given on a trial-and-error basis.

CONCLUSION

To treat all children with asthma equally effectively from infancy through adolescence does not mean that they should be treated identically and in some types of asthma a trial-and-error approach may be warranted.

Exhaled nitric oxide measurements in the first 2 years of life: methodological issues, clinical and epidemiological applications

Fractional exhaled nitric oxide (FeNO) is a useful tool to diagnose and monitor eosinophilic bronchial inflammation in asthmatic children and adults. In children younger than 2 years of age FeNO has been successfully measured both with the tidal breathing and with the single breath techniques. However, there are a number of methodological issues that need to be addressed in order to increase the reproducibility of the FeNO measurements within and between infants. Indeed, a standardized method to measure FeNO in the first 2 years of life would be extremely useful in order to meaningfully interpret FeNO values in this age group. Several factors related to the measurement conditions have been found to influence FeNO, such as expiratory flow, ambient NO and nasal contamination. Furthermore, the exposure to pre- and postnatal risk factors for respiratory morbidity has been shown to influence FeNO values. Therefore, these factors should always be assessed and their association with FeNO values in the specific study population should be evaluated and, eventually, controlled for.

There is evidence consistently suggesting that FeNO is increased in infants with family history of atopy/atopic diseases and in infants with recurrent wheezing. These findings could support the hypothesis that eosinophilic bronchial inflammation is present at an early stage in those infants at increased risk of developing persistent respiratory symptoms and asthma. Furthermore, it has been shown that FeNO measurements could represent a useful tool to assess bronchial inflammation in other airways diseases, such as primary ciliary dyskinesia, bronchopulmonary dysplasia and cystic fibrosis. Further studies are needed in order to improve the reproducibility of the measurements, and large prospective studies are warranted in order to evaluate whether FeNO values measured in the first years of life can predict the future development of asthma or other respiratory diseases.

The potential use of spirometry during methacholine challenge test in young children with respiratory symptoms

BACKGROUND

The concentration of methacholine that causes a fall of 20% from baseline forced expiratory volume in the first second (PC20-FEV1) in the methacholine challenge test (MCT) is not usually considered a diagnostic tool in preschool children since PC20-FEV1 may not be achievable <6 years of age.

AIM

To assess the usefulness of various spirometry indices obtained during MCT in a large group of 3- to 6-year-old children with respect to their clinical diagnosis.

METHODS

Standardized MCT (inhaled triple-concentration increments [0.057-13.925 mg] of methacholine solution) was performed by 84 children previously diagnosed with asthma (asthmatics) and 48 with prolonged cough (coughers). Spirometry was determined at baseline and between inhalations; PC20-FEV1 and PC25-FEV0.5 were calculated.

RESULTS

PC20-FEV1 values were significantly less in the asthmatics than in the coughers (mean +/- SD was 3.21 +/- 4.32 vs. 22.35 +/- 3.66 ml/mg). Similarly, PC25-FEV0.5 was 1.48 +/- 3.08 in the asthmatics and 9.45 +/- 12.59 mg/ml/Mch in the coughers, P < 0.0001. A cut-off at 4.0 mg/ml for PC20-FEV1 had 77.4% sensitivity and 75.0% specificity, a cut-off at 2.2 mg/ml for PC25-FEV0.5 had 73.8% sensitivity and 72.9% specificity, for clinical diagnosis of asthma. PC25-FEV0.5 also showed a correlation with age.

CONCLUSIONS

Our findings suggest that MCT can be performed in preschool children with various respiratory symptoms. PC25-FEV0.5 may be a better end-point parameter. Children with a clinical diagnosis of asthma respond to a lower MCT concentration than children with cough. Further studies are needed to determine airway responsiveness in healthy young children and to further assess the contribution of MCT to the clinical diagnosis in this age group.

[Exhaled nitric oxide in children under 4 years of age with recurrent bronchitis]

BACKGROUND

The objective of the study was to assess bronchial inflammation in preschool children with recurrent bronchitis by measuring exhaled nitric oxide.

PATIENTS AND METHODS

The study included patients under 4 years of age with at least 3 episodes of wheezing in the past year (n=63) and a control group (n=30). Exhaled nitric oxide was measured in samples collected offline during spontaneous tidal breathing with a face mask and stored in Mylar balloons.

RESULTS

The fractional exhaled nitric oxide concentration (FE(NO)) was higher in the group with bronchitis (mean [SD], 5.3 [1.3] parts per billion [ppb]) than in the control group (4.6 [1.1]ppb) (P=.02). There was a significant difference between the control group and children in the bronchitis group not treated with inhaled corticosteroids (P<.05), but not between controls and corticosteroid-treated patients. A relationship with eosinophil count was observed in that those with higher counts (>400 microL) had higher FE(NO) levels (P<.01). No relationship was observed between FE(NO) and a positive methacholine challenge test. Follow-up lasted at least 20 months. The initial FE(NO) level did not differ significantly according to whether patients were subsequently transient, infrequent, or frequent wheezers (5.2 [0.98]ppb, 5.6 [1.5]ppb, and 4.8 [1.34]ppb, respectively; P=.36).

CONCLUSIONS

In children under 4 years of age with recurrent wheezing bronchitis who were asymptomatic at study entry, a small increase in FE(NO) was observed although there was a good deal of overlap with the control group.

Montelukast in guidelines and beyond

In all asthma guidelines, preventive anti-inflammatory treatment is essential in all patients with persistent asthma. Inhaled corticosteroids are the mainstay of treatment in the control of asthma, but other treatments may be used as a monotherapy in patients with mild asthma or as an add-on treatment in those with moderate-to-severe asthma. Leukotriene modifiers are the only validated preventive treatment for all age groups. This review discusses the place of montelukast, a leukotriene receptor antagonist, using guidelines and consensus reports on asthma and rhinitis: the US National Asthma Education and Prevention Program (NAEPP); the British Guideline on the Management of Asthma; the Global Initiative on Asthma (GINA); and Allergic Rhinitis and its Impact on Asthma (ARIA). This review includes new studies that have not yet been considered in guidelines.