Official American Thoracic Society Clinical Practice Guidelines: Diagnostic Evaluation of Infants with Recurrent or Persistent Wheezing

A study of etiology and asthma risks in infants and toddlers hospitalized for recurrent or persistent wheezing

Objective

To study the etiology of recurrent and persistent wheezing in infants and toddlers, and identify the risk factors for infantile asthma.

Methods

We retrospectively analyzed the data of 612 children (aged 0-36 months) hospitalized for recurrent or persistent wheezing between 2019.09.01 and 2022.08.31. We comparatively analyzed their clinical, laboratory, imaging, and lung-examination data between different groups. Multivariate logistic regression analysis was used to identify risk factors for asthma.

Results

The etiologies of recurrent and persistent wheezing significantly differed (P < 0.05). The top 3 causes of recurrent wheezing were viral infections (48.4%), infantile asthma (28.0%), and protracted bacterial bronchitis (PBB; 9.5%), whereas the top 3 causes of persistent wheezing were PBB (67.5%), tracheomalacia (22.2%), and infantile asthma (15.9%). The distribution of etiologies varied by age. Bronchoscopy was performed for 181 children, and mainly showed purulent changes (34.3%), tracheomalacia (27.1%), and positive pathogenic bronchoalveolar lavage fluid (25.4%). Older age, admission to the intensive care unit (ICU), positive modified Asthma Prediction Index (mAPI), and food allergy were risk factors for asthma. The odds ratio of mAPI was 4.066. The area under the receiver operating characteristic curve of the risk factors for predicting asthma was 0.8016.

Conclusion

Wheezing phenotype and age may partly guide the etiological diagnosis of recurrent/persistent wheezing in infants and young children. Bronchoscopy is important for the diagnosis of refractory recurrent/persistent wheezing, while mAPI aids in the diagnosis of asthma. When infants and children with recurrent or persistent wheezing have the characteristics of older age, ICU admission, positive mAPI, and food allergy, the possibility of asthma may be considered.

The wheezy infant: A viewpoint from low-middle income countries

OBJECTIVE

To review the recent evidence in the literature of various aspects of recurrent/severe wheezing in children under 3 in low-middle income countries [LMICS].

SOURCES

A non-systematic review including articles in English. We mainly selected publications from the last 5 years. Studies on epidemiology, aetiology, diagnosis, treatment, and prevention were included in the search. We reviewed differential diagnoses of wheezing that focused on LMICS. We also reviewed aspects of prevention.

SUMMARY OF THE FINDINGS

Many epidemiological studies have shown a variable but significant number of wheezy infants [WI] cases in LMICS when compared to other countries. The differential diagnosis of causes of wheezing in this age group is mandatory, taking into account local facilities. Few treatment options have been well studied for this age group. In LMICS, a pragmatic approach could be considered, as described in the article. It is difficult to study primary prevention for WI and secondary prevention (mainly environmental) may have some impact. A schematic approach for recurrent wheezers is presented, which takes into account settings with limited resources.

CONCLUSION

Severely or recurrently wheezy children under 3 is a common clinical issue in LMICS. Studies on this age group are needed to reduce the significant morbidity. It may be possible to lower the high burden of wheezing in this age group by selecting the phenotype which may respond to inhaled steroids.

A Quality Improvement Initiative to Minimize Unnecessary Chest X-Ray Utilization in Pediatric Asthma Exacerbations

Background

Current national guidelines recommend against chest X-rays (CXRs) for patients with acute asthma exacerbation (AAE). The overuse of CXRs in AAE has become a concern, prompting the need for a quality improvement (QI) project to decrease CXR usage through guideline-based interventions. We aimed to reduce the percentage of CXRs not adhering to national guidelines obtained for pediatric patients presenting to the Emergency Department (ED) with AAE by 50% within 12 months of project initiation.

Methods

We conducted this study at a New York City urban level-2 trauma center. The team was composed of members from the ED and pediatric departments. Electronic medical records of children aged 2 to 18 years presenting with AAE were evaluated. Monthly data on CXR utilization encompassing instances where the ordered CXR did not adhere to guidelines was collected before and after implementing interventions. The interventions included provider education, visual reminders, printed cards, grand-round presentations, and electronic medical records modifications.

Results

The study encompassed 887 eligible patients with isolated AAE. Baseline data revealed a mean preintervention CXR noncompliance rate of 37.5% among children presenting to the ED with AAE. The interventions resulted in a notable decrease in unnecessary CXR utilization, reaching 16.7%, a reduction sustained throughout subsequent months.

Conclusions

This QI project successfully reduced unnecessary CXR utilization in pediatric AAE. A multi-faceted approach involving education, visual aids, and electronic reminders aligned clinical practice with evidence-based guidelines. This QI initiative is a potential template for other healthcare institutions seeking to curtail unnecessary CXR usage in pediatric AAE.

Efficacy and safety of fluticasone propionate/salmeterol and fluticasone propionate monotherapy in step-up treatment of childhood asthma: A systematic review and meta-analysis

BACKGROUND

Asthma is a chronic respiratory disease that affects millions of children worldwide and can impair their quality of life and development. Inhaled glucocorticoids are the mainstay of asthma treatment, but some children require step-up therapy with additional drugs to achieve symptom control. Fluticasone propionate and salmeterol (FSC) has been shown to reduce asthma exacerbations and improve lung function in adults. However, the evidence for its efficacy and safety in children is limited.

OBJECTIVE

This study aims to provide a comprehensive basis for treatment selection by summarizing existing clinical randomized controlled trials (RCTs) on the efficacy of FSC compared to fluticasone propionate (FP) monotherapy in children with asthma who require step-up treatment.

METHODS

Five online databases and three clinical trial registration platforms were systematically searched. The effect size and corresponding 95% confidence interval (CI) were calculated based on the heterogeneity among the included studies.

RESULTS

Twelve RCTs were identified and a total of 9, 859 patients were involved. The results of the meta-analysis revealed that the use of FSC was associated with a greater reduction in the incidence of asthma exacerbations than FP alone when the dose of FP was the same or when the duration of treatment exceeded 12 weeks. In addition, FSC resulted in a greater proportion of time with asthma-free and without the use of albuterol compared to FP alone when the duration of treatment exceeded 12 weeks. No significant differences were observed between FSC and FP alone in the incidence of drug-related adverse events and other adverse events.

CONCLUSION

Both FSC and FP alone are viable options for the initial selection of step-up treatment in asthmatic children. While, FSC treatment demonstrates a greater likelihood of reducing asthma exacerbations which is particularly important for reducing the personnel, social and economic burden in children requiring step-up asthma treatment.

The effect of immunomodulatory therapy with recombinant human interferon alpha-2β on blood cytokine levels in children with recurrent episodes of acute obstructive bronchitis

The high incidence of children with recurrent episodes of acute obstructive bronchitis is a widespread problem. Correct identification of children at risk of developing bronchial asthma at school age may improve treatment and prevention approaches to this pathology, but the ability to identify these children remains limited. The purpose of the study was to determine the effectiveness of recombinant interferon alpha-2β in children with recurrent episodes of acute obstructive bronchitis in the course of treatment based on the assessment of cytokine profile. The study examined 59 children of the main group with recurrent episodes of acute obstructive bronchitis and 30 children of the comparison group who suffered from acute bronchitis, aged 2-8 years, who were in the hospital. The results of laboratory studies were compared with the data of 30 healthy children. In children with recurrent episodes of acute obstructive bronchitis, the content of serum interferon-γ and interleukin-4 was significantly reduced compared to healthy children, after treatment with recombinant human interferon alpha-2β, the content of interferon-γ and interleukin-4 in children significantly increased. The content of interleukin-1β in children with recurrent episodes of acute obstructive bronchitis was significantly higher than in healthy children, after immunomodulatory therapy with recombinant interferon alpha-2β, interleukin-4 normalized to its level in healthy children. It was found that children with recurrent episodes of acute obstructive bronchitis have an imbalance of cytokines, the effectiveness of recombinant human interferon alpha-2β therapy, which normalized the levels of the studied cytokines in the serum.

Metabolomics of bronchoalveolar lavage in children with persistent wheezing

Background

Recent studies have demonstrated the important role of metabolomics in the pathogenesis of asthma. However, the role of lung metabolomics in childhood persistent wheezing (PW) or wheezing recurrence remains poorly understood.

Methods

In this prospective observational study, we performed a liquid chromatography/mass spectrometry-based metabolomic survey on bronchoalveolar lavage samples collected from 30 children with PW and 30 age-matched infants (control group). A 2-year follow-up study on these PW children was conducted.

Results

Children with PW showed a distinct characterization of respiratory metabolome compared with control group. Children with PW had higher abundances of choline, oleamide, nepetalactam, butyrylcarnitine, l-palmitoylcarnitine, palmitoylethanolamide, and various phosphatidylcholines. The glycerophospholipid metabolism pathway was the most relevant pathway involving in PW pathophysiologic process. Additionally, different gender, prematurity, and systemic corticoids use demonstrated a greater impact in airway metabolite compositions. Furthermore, for PW children with recurrence during the follow-up period, children who were born prematurely had an increased abundance of butyrylcarnitine relative to those who were carried to term.

Conclusions

This study suggests that the alterations of lung metabolites could be associated with the development of wheezing, and this early alteration could also be correlated with wheezing recurrence later in life.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-02087-6.

Treatment of Pediatric Patients With High-Flow Nasal Cannula and Considerations for Oral Feeding: A Review of the Literature

PURPOSE

High-Flow Nasal Cannula (HFNC) has become an increasingly common means of noninvasive respiratory support in pediatrics and is being used in infants and children with respiratory distress both inside and outside of the intensive care units. Despite the widespread use of HFNC, there remains a paucity of data on optimal flow rates and its impact on morbidity, mortality, and desired outcomes. Given the scarcity of information in these critical areas, it is not surprising that guidelines for initiation of oral feeding do not exist. This review article will review HFNC mechanisms of action, its use in specific populations and settings, and finally what is known about initiation of feeding during this therapy.

CONCLUSIONS

The practice of withholding oral feeding solely, because of HFNC, is not supported in the literature at the time of this writing, but in the absence of safety data from clinical trials, clinicians should proceed with caution and consider patient-specific factors while making decisions about oral feeding. Well-controlled prospective clinical trials are needed for development of best practice clinical guidelines and attainment of optimal outcomes.

Bronchoalveolar lavage profiles in uncontrolled wheezy children compared by asthma predictive index

OBJECTIVE

The asthma predictive index (API) predicts later asthma in preschoolers with frequent wheeze. We hypothesized that airway cytology differs between API positive (API+)/negative (API-) children with uncontrolled/recurrent wheezing with dominance of eosinophils in API+ and neutrophils in API- groups respectively. The main objective of this study is to compare bronchoalveolar lavage (BAL) cell profiles in API+/API- children with recurrent wheezing unresponsive to inhaled corticosteroids (ICS).

DESIGN

Retrospective analysis of BAL in 43 children, 3-36 months (median: 14 months) receiving ICS (31 API+, 12 API-). BAL cell differential counts, bacterial/viral cultures, and lipid-laden macrophage percentages were analyzed. Cell counts presented as median (range).

RESULTS

Neutrophil percentages were increased in both groups (API- 16% [1%-76%]; API+ 42% [1%-95%]; p = NS). Cell percentages were similar for lymphocytes (API- 12% [1%-30%]; API+ 7% [1%-37%]), and macrophages (API- 67.5% [12%-97%]; API+ 41% [2%-94%]). Eosinophil percentages were low in both groups (API- 1% [1%-2%]; API+ 1% [1%-11%]). There was no difference in cellular distributions using absolute cell counts comparing API groups. Bacterial cultures were positive in 18 (60%) API+ and 5 (41%) API- patients (p = 0.10).

CONCLUSION

Cell profiles do not differ between API groups in children ≤36 months with recurrent wheezing unresponsive to ICS. Neutrophil percentages and total granulocyte count correlate with positive bacterial cultures independent of API status. Persistent bacterial bronchitis likely plays an important role in the persistence of symptoms unresponsive to ICS therapy regardless of API status with a trend to more positive cultures in API positive children.

Mycoplasma Pneumoniae Infection and Persistent Wheezing in Young Children: A Retrospective Case-Control Study

BACKGROUND

To investigate the clinical characteristics of children with persistent wheezing (PW) with Mycoplasma pneumoniae (MP) DNA in bronchoalveolar lavage fluid (BALF).

METHODS

This retrospective case-control study included consecutive admitted children under 3 years of age who were diagnosed with PW and had MP DNA detected in BALF. Patients with mycoplasma pneumoniae pneumonia (MPP) and foreign-body aspiration (FBA) were enrolled as controls. The clinical characteristics of the groups were compared.

RESULTS

During the study period, there were 89 patients diagnosed with PW without structural anomalies of the conductive airways, and 30 of these patients (33.7%, 30/89) with MP DNA detected in the BALF were selected as the study group. We included 44 patients with MPP and 44 patients with FBA as controls. Patients with MPP were older and had a higher occurrence of fever and C-reactive protein (CRP) than patients with PW (all P < 0.001). The median MP DNA copy number in patients with MPP was higher than that of patients with PW (P = 0.004). The median level of MP IgG in patients with PW was lower than that of patients with MPP and higher than that of patients with FBA (all P < 0.001). MP DNA copy number positively correlated with age (r = 0.392, P = 0.001) and CRP (r = 0.235, P = 0.048).

CONCLUSIONS

Our study reveals that MP was highly detected in the BALF of PW patients. In addition, young patients with a low load of MP infection showed lower amounts of antibody, and a weak inflammatory response might be associated with PW.

Outpatient Respiratory Management of Infants, Children, and Adolescents with Post-Prematurity Respiratory Disease: An Official American Thoracic Society Clinical Practice Guideline

Background: Premature birth affects millions of neonates each year, placing them at risk for respiratory disease due to prematurity. Bronchopulmonary dysplasia is the most common chronic lung disease of infancy, but recent data suggest that even premature infants who do not meet the strict definition of bronchopulmonary dysplasia can develop adverse pulmonary outcomes later in life. This post-prematurity respiratory disease (PPRD) manifests as chronic respiratory symptoms, including cough, recurrent wheezing, exercise limitation, and reduced pulmonary function. This document provides an evidence-based clinical practice guideline on the outpatient management of infants, children, and adolescents with PPRD. Methods: A multidisciplinary panel of experts posed questions regarding the outpatient management of PPRD. We conducted a systematic review of the relevant literature. The Grading of Recommendations, Assessment, Development, and Evaluation approach was used to rate the quality of evidence and the strength of the clinical recommendations. Results: The panel members considered the strength of each recommendation and evaluated the benefits and risks of applying the intervention. In formulating the recommendations, the panel considered patient and caregiver values, the cost of care, and feasibility. Recommendations were developed for or against three common medical therapies and four diagnostic evaluations in the context of the outpatient management of PPRD. Conclusions: The panel developed recommendations for the outpatient management of patients with PPRD on the basis of limited evidence and expert opinion. Important areas for future research were identified.

Finding a molecular genetic marker for the incidence of recurrent episodes of acute obstructive bronchitis in children

Over the last ten years, the incidence of the pathology of the bronchus-pulmonary system in children has increased 3.6 times, mainly due to acute and recurrent inflammatory diseases of the upper and lower respiratory tract. Thus, the problem of identifying children with recurrent episodes of acute obstructive bronchitis and an increased risk of developing asthma is relevant and promising. The goal of this study was to find molecular genetic markers associated with increased susceptibility of children to repeated episodes of acute obstructive bronchitis. The molecular genetic testing of the IL4 gene of a single nucleotide polymorphism C-33T was performed in 35 children with recurrent episodes of acute obstructive bronchitis and 35 children with acute bronchitis. The results were statistically processed on a personal computer with the calculation of values the arithmetic mean (M), of the errors arithmetic mean (m), Student criterion (t), the degree of probability (p), Pearson criterion (χ2), and the odds ratio (OR). Statistically significant differences were figured at p<0.01 and p<0.05. It has been proved that the presence of a child's genotype 33CT IL4 increases the risk of recurrent acute obstructive bronchitis four times.

Pediatric flexible bronchoscopy: A single-center report

INTRODUCTION

Pediatric flexible laryngotracheal bronchoscopy (FB) is an integral part of diagnostics and treatment at tertiary pediatric respiratory centers.

AIM

FBs performed between 2013 and 2018 at our Pediatric Allergy and Respiratory Medicine Unit of the Department of Women's and Children's Health at Padua University were examined in terms of the indications, findings, and adverse events.

MATERIALS AND METHODS

The electronic medical records of pediatric patients who underwent FB at least once between 1 January 2013 and 31 December 2018 were considered. Patients' clinical data, indications for FB, anatomical findings, information derived from bronchoalveolar lavage (BAL) and bronchial brushing, and possible adverse events were analyzed.

RESULTS

There were 447 pediatric FBs performed in 428 patients (aged from 1 month to 18 years) for diagnostic purposes (92.4%), to clear secretions (3.6%), or to monitor a known condition (4.0%). The main indications were recurrent lower respiratory tract infections (LRTI, 32.2%) and chronic wet cough (9.4%). Lower airway malacia was the most common abnormal finding in these two groups (36.1% and 28.6%, respectively). BAL bacterial culture was positive in 55 children (39.6%) with recurrent LRTI and in 25 (59.5%) with chronic wet cough, being Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis the microorganisms most commonly isolated. FB proved a safe procedure and was well tolerated.

CONCLUSIONS

Pediatric FB is an essential tool at our tertiary pediatric respiratory center. It helps establish the anatomical conditions underlying several chronic respiratory conditions and any correlated microbiological findings, with a significant impact on further patient management.

Follow-up study of airway microbiota in children with persistent wheezing

Background

Increasing evidence revealed that airway microbial dysbiosis was associated with increased risk of asthma, or persistent wheezing (PW). However, the role of lung microbiota in PW or wheezing recurrence remains poorly understood.

Methods

In this prospective observational study, we performed a longitudinal 16S rRNA-based microbiome survey on bronchoalveolar lavage (BAL) samples collected from 35 infants with PW and 28 age-matched infants (control group). A 2-year follow-up study on these PW patients was conducted. The compositions of lower airway microbiota were analyzed at the phylum and genus levels.

Results

Our study showed a clear difference in lower airway microbiota between PW children and the control group. Children with PW had a higher abundance of Elizabethkingia and Rothia, and lower abundance of Fusobacterium compared with the control group. At the end of the 2-year follow-up, 20 children with PW (57.1%) experienced at least one episode of wheezing, and 15 (42.9%) did not suffer from wheezing episodes. Furthermore, PW children with recurrence also had increased abundances of Elizabethkingia and Rothia relative to those who had no recurrence. Additionally, wheezing history, different gender, and caesarean section demonstrated a greater impact in airway microbiota compositions.

Conclusion

This study suggests that the alterations of lower airway microbiota could be strongly associated with the development of wheezing, and early airway microbial changes could also be associated with wheezing recurrence later in life.

Medical care and treatment of children with asthmatic or wheezing health outcomes and urban-rural differences in Bavaria - a cross-sectional study

Introduction: Asthma is among the most common chronic conditions in children. The aim of this publication is to describe prevalence rates and factors associated with asthmatic or wheezing preschoolers and to evaluate medical care and treatment with regard to urban-rural differences.Methods: Data for this cross-sectional study were collected through a questionnaire, which was distributed to parents within the Health Monitoring Units in Bavaria (HMU), Germany. Data from 4767 children were available (2016/17). Those children were classified into four diagnostic groups: Unremitting Wheeze, International Study of Asthma and Allergies in Children (ISAAC) Asthma, Physician-diagnosed Asthma, and healthy control group. Urban-rural differences were tested by Pearson's chi-squared test or by Fisher's exact test. Independent variables were factors associated with health outcomes, for example, residency or migrant status. To examine associations between independent and outcome variables multivariate logistic regression analysis was performed.Results: Prevalence rates were 6.3% for 'Unremitting Wheeze', 5.2% for 'ISAAC Asthma', and 1.2% for 'Physician-diagnosed Asthma'. Factors associated with health outcomes were the occurrence of asthma in first-degree relatives, male sex, and migrant status. Generally, higher rates of doctor's visits, positive allergy tests, and corticosteroids intake in the diagnostic groups in rural compared to urban areas were observed. Rates of performed allergy tests were 55.6% for 'ISAAC Asthma' and 74.6% for 'Physician-diagnosed Asthma'.Conclusions: Prevalence rates of the diagnostic groups decreased compared to the HMU 2014/15. According to previous studies, factors associated with asthmatic or wheezing health outcomes could be confirmed. Children in rural areas generally received more medical care.Key pointsChildren's prevalence rates of asthma or wheezing disorders decreased in the past 2 years within Bavaria.This study is consistent with risk factors for asthma from the literature: asthma in the family, male gender, and migrant status.Children in rural areas receive more medical care than children in urban areas.There should me more allergy tests among children with medical diagnosis in Bavaria as low rates indicate gaps in care.

Novel Treatment-Refractory Preschool Wheeze Phenotypes Identified by Cluster Analysis of Lung Lavage Constituents

BACKGROUND

Preschool children with treatment-refractory wheeze often require unscheduled acute care. Current guidelines advise treatment of persistent wheeze with inhaled corticosteroids. Alternative treatments targeting structural abnormalities and specific inflammatory patterns could be more effective.

OBJECTIVE

To apply unsupervised analysis of lung lavage (bronchoalveolar lavage [BAL]) variables to identify clusters of preschool children with treatment-refractory wheeze.

METHODS

A total of 155 children 6 years or younger underwent bronchoscopy with BAL for evaluation of airway structure, inflammatory markers, and pathogens. Variables were screened with factor analysis and sorted into clusters by Ward's method, and membership was confirmed by discriminant analysis.

RESULTS

The model was repeatable in a 48-case validation sample and accurately classified 86% of cases. Cluster 1 (n = 60) had early-onset wheeze, 85% with structural abnormalities, mostly tracheamalacia, with low total IgE and agranulocytic BAL. Cluster 2 (n = 42) had later-onset wheeze, the highest prevalence of gastroesophageal reflux, little atopy, and two-third had increased BAL lipid-laden macrophages. Cluster 3 (n = 46) had mid-onset wheeze, low total IgE, and two-third had BAL viral transcripts, predominately human rhinovirus, with BAL neutrophilia. Cluster 4 (n = 7) was older, with high total IgE, blood eosinophilia, and mixed BAL eosinophils and neutrophils.

CONCLUSIONS

Preschool children with recurrent wheeze refractory to inhaled corticosteroid treatment include 4 clusters: airway malacia, gastroesophageal reflux, indolent human rhinovirus bronchoalveolitis, and type-2^high inflammation. The results support the risk and cost of invasive bronchoscopy to diagnose causes of treatment-refractory wheeze and develop novel therapies targeting airway malacia, human rhinovirus infection, and BAL neutrophilia in preschool children.

Patterns of respiratory health services utilization from birth to 5 years of children who experienced adverse birth outcomes

Introduction

Adverse birth outcomes have important consequences for future lung health. We evaluated patterns of respiratory health services utilization in early childhood among children born preterm (PTB), small and large for gestational age at term (SGA and LGA, respectively), and appropriate-for-gestational age at term.

Materials and methods

We conducted a population-based retrospective cohort study using administrative health data of all singleton live births in Alberta, Canada between 2005–2010. Data on hospitalizations and emergency department (ED) visits from birth to 5 years were collected for asthma, bronchitis, bronchiolitis, croup, influenza, pneumonia, and other acute upper and lower respiratory tract infections (other URTI and other LRTI, respectively). Adjusted rate ratios were estimated for respiratory ED visits and hospitalizations for adverse birth outcomes using the appropriate-for-gestational age at term group as reference. Age-specific trajectories of total respiratory health services utilization rates for each group were estimated in Poisson models.

Results

A total of 293,764 episodes of respiratory care from 206,994 children were analyzed. Very PTB children had the highest rates of health services use for all respiratory conditions, particularly for asthma, pneumonia, and bronchiolitis hospitalizations. Moderate/late PTB children also had elevated ED visits and hospitalizations for all respiratory conditions. Children born SGA showed high rates of ED visits for other LRTI, and of hospitalizations for bronchitis, bronchiolitis, and other URTI. Children born LGA had high rates of croup and other URTI ED visits, and of bronchiolitis and bronchiolitis hospitalizations. Age-specific trajectories showed a decreasing trend in the rates of total respiratory health service utilization from birth to five years of age for all groups studied. Children born PTB and LGA at term significantly required more respiratory health services over time compared to the reference group.

Conclusion

Patterns of paediatric respiratory health services utilization vary according to gestational age and fetal growth.

Pediatric bronchoscopy: recent advances and clinical challenges

Introduction: During the last 40 years equipment has been improved with smaller instruments and sufficient size working channels. This has ensured that bronchoscopy offers therapeutic and interventional options.Areas covered: We provide a review of recent advances and clinical challenges in pediatric bronchoscopy. This includes single-use bronchoscopes, endobronchial ultrasound, and cryoprobe. Bronchoscopy in persistent preschool wheezing and asthma is included. The indications for interventional bronchoscopy have amplified and included balloon dilatation, endoscopic intubation, the use of airway stents, whole lung lavage, closing of fistulas and air leak, as well as an update on removal of foreign bodies. Others include the use of laser and microdebrider in airway surgery. Experience with bronchoscope during the COVID-19 pandemic has been included in this review. PubMed was searched for articles on pediatric bronchoscopy, including rigid bronchoscopy as well as interventional bronchoscopy with a focus on reviewing literature in the past 5 years.Expert opinion: As the proficiency of pediatric interventional pulmonologists continues to grow more interventions are being performed. There is a scarcity of published evidence in this field. Courses for pediatric interventional bronchoscopy need to be developed. The COVID-19 experience resulted in safer bronchoscopy practice for all involved.

Preschool wheezing and asthma in children: A systematic review of guidelines and quality appraisal with the AGREE II instrument

BACKGROUND

Asthma-like symptoms in preschool children, such as wheezing and dyspnea, are common time- and resource-consuming diagnostic and management challenges. Quality of wheezing and asthma recommendations varies. The purpose of this study, carried out by the European Academy of Allergy and Clinical Immunology (EAACI) Task Force for Preschool Wheeze, was to systematically review and assess the quality of guidelines for diagnosis and treatment of preschool wheezing and/or asthma.

METHODS

The Cochrane Library, MEDLINE, and EMBASE were searched until June 2018. The methodological rigor, quality, and transparency of relevant guidelines were assessed with the use of the Appraisal of Guidelines for Research and Evaluation (AGREE II) tool.

RESULTS

We identified 26 guidelines. The quality scores for each domain varied. Of all domains, clarity and presentation had the highest mean score, whereas applicability and stakeholder involvement had the lowest. The scores (median) for individual domains were as follows: score and purpose 86%; stakeholder involvement 49%; rigor of development 54%; clarity of presentation 85%; applicability 51%; and editorial independence 63%.

CONCLUSION

Although several guidelines on asthma management in children are available, however, their quality varies. Additionally, there is a considerable gap in reliable recommendations on the management and treatment of non-asthmatic preschool wheeze.

Flexible Bronchoscopy in Evaluation of Persistent Wheezing in Children-Experiences from National Pediatric Center

Background and objectives: Persistent wheezing (PW) is defined as prolonged or recurrent episodes of wheezing despite regular treatment. Flexible bronchoscopy (FB) is recommended to determine the etiology of PW in children. This study aimed to determine the etiology of PW based on FB findings in a national pediatric center. Materials and Methods: Children presenting with PW that underwent flexible bronchoscopy from April 2016 to August 2019 at the Mother and Child Health Institute of Serbia were included in this observational study. After endoscopic evaluation, bronchoalveolar lavage fluid (BALF) samples were taken and further analyzed. Quantitative microbiology, cytological analysis and oil-red staining of specimens were performed to determine cellular constituents and presence of lipid laden macrophages (LLM). Upper gastrointestinal series were performed to exclude gastroesophageal reflux disease, swallowing dysfunction and vascular ring. Results: Pathological findings were revealed in 151 of 172 study participants, with bacterial lower airway infection (BLAI) (48.3%) and primary bronchomalacia (20.4%) as the most common. Younger participants were hospitalized for significantly longer periods (ρ = −0.366, p < 0.001). Study participants with BLAI and associated mucus plugging were notably younger (p < 0.001). Presence of LLM in BALF was not associated with findings of upper gastrointestinal series. All patients with confirmed BLAI were treated with oral antibiotics. Although FB is considered to be invasive, there were no complications associated with the procedure. Conclusions: Flexible bronchoscopy has an exceptional diagnostic value in evaluation of PW. In younger patients with BLAI, presence of mucus plugs may complicate the clinical course, so significant benefits can be achieved with therapeutic lavage during bronchoscopy.

Exhaled Nitric Oxide in Wheezy Infants Predicts Persistent Atopic Asthma and Exacerbations at School Age

BACKGROUND

There are limited data assessing the predictive value of fraction of exhaled nitric oxide (FENO) in infants/toddlers with recurrent wheezing for asthma at school age.

OBJECTIVES

In a cohort of infants/toddlers with recurrent wheezing determine the predictive values of sedated single-breath FENO (SB-FENO) and awake tidal-breathing mixed-expired FENO (tidal-FENO) for active asthma, severe exacerbations, and lung function at age 6 years.

METHODS

In 44 infants/toddlers, SB-FENO was measured under sedation at 50 mL/sec in conjunction with forced expiratory flow and volume measurements, and tidal-FENO was measured during awake tidal breathing. Clinical outcomes and lung function were assessed at age 6 years in 36 subjects.

RESULTS

Enrollment SB-FENO was significantly higher among subjects with active asthma at age 6 years than among subjects without asthma (36.4 vs. 16.9 ppb, p < 0.0001), and the odds of asthma was 7.6 times greater (OR 7.6; 95% CI 1.8-31.6) for every 10 ppb increase in enrollment SB-FENO. A ROC analysis demonstrated that an enrollment SB-FENO > 31.5 ppb predicted active asthma at age 6 years with an area under the curve (AUC) of 0.92 (95% CI: 0.82-1). SB-FENO was also higher among subjects who experienced severe asthma exacerbations during the year preceding age of 6 years. SB-FENO at enrollment and lung function measures at age 6 years were modestly correlated (FEV1: r = -0.4; FEF25-75: r = -0.41; FEV1/FVC ratio: r=-0.46), and SB-FENO was significantly higher among subjects with bronchodilator responsiveness (BDR) at age 6 years. Tidal-FENO was not predictive of active asthma, exacerbations, or lung function at age 6 years.

CONCLUSION

In wheezy infants/toddlers, SB-FENO was predictive of school-age asthma and associated with lung function measures at age 6 years.

Pilot study shows right ventricular diastolic function impairment in young children with obstructive respiratory disease

AIM

This study determined cardiovascular impairment in young children with obstructive respiratory disease who were assessed using the opening interrupter technique (RINT).

METHODS

This pilot study enrolled 41 children who had been referred to pulmonology and allergology specialists at the University of Catania, Italy, from March to July 2017: 23 (mean age 4.13 ± 0.62 years) had chronic coughs and wheezing and 18 controls (mean age 4.27 ± 0.66 years) had obstructive chest disease, but were otherwise healthy. Airway resistance was evaluated using RINT and cardiac function by studying the ejection fraction, pulmonary artery systolic pressure (PASP), tricuspid annular plane systolic excursion and tricuspid flow propagation velocity (TFPV).

RESULTS

The RINT and PASP values were significantly higher in the patient group when compared to the controls, but the TFPV values were lower. A direct and significant Spearman's correlation coefficient (r) between RINT and PASP values was observed (r = 0.81). We found a significant inverse correlation between RINT and TFPV (r = -0.83), as well as TFPV and PASP (r = -0.78).

CONCLUSION

This study showed that children with obstructive respiratory diseases had a major risk of cardiovascular impairment. Impaired diastolic function of the right ventricle occurred very early when airway resistance was abnormally increased.

Advances in the aetiology, management, and prevention of acute asthma attacks in children

Acute attacks of wheeze or asthma are among the most common reasons for paediatric hospital attendance, and the incidence of severe attacks in the UK is among the highest in Europe. Although most attacks are driven by infection, there are important differences in the underlying pathophysiology of asthma and wheeze between preschool and school-aged children. Allergen sensitisation, airway eosinophilia, and type 2 inflammation predominate in older children, whereas phenotypes in preschool children are variable, often including non-atopic episodes driven by neutrophilic infection. Currently, a universal approach is adopted towards management, but there is a need to make objective assessments of airway function, inflammation, and infection, both during the attack and during stable periods, to identify treatable traits and to target therapy if outcomes are to be improved. An assessment of the risk factors that led to the attack and early, focused follow-up are essential to ensure attacks never occur again.

Asthma in Children: A Brief Review for Primary Care Providers

Pediatric asthma is a common chronic condition with wide-ranging implications for children's health, their families, and the health care system. The diagnosis may be relatively straightforward for the child with characteristic symptoms, triggers, and response to therapy, but there are other less common presentations that can make the diagnosis challenging. Diagnosing asthma in a toddler with recurrent wheezing can be particularly difficult. Treating asthma in a step-wise fashion usually reduces symptom frequency and improves asthma control. Asthma exacerbations and poor outcomes from acute exacerbations remain an area in which we have room for improvement. This article provides an overview of the diagnosis and management of childhood asthma for the primary care provider. [Pediatr Ann. 2019;48(3):e103-e109.].

Persistent Wheeze in Infants: A Guide for General Pediatricians

Infants with persistent wheeze is a common diagnostic challenge for the general pediatrician because of the broad differential diagnoses. The initial diagnostic approach should include a comprehensive history, physical examination, and chest radiography. Additional testing may be warranted. Involvement of a pediatric pulmonary subspecialist may also be indicated. [Pediatr Ann. 2019;48(3):e110-e114.].

Eosinophil cell count in bronchoalveolar lavage fluid in early childhood wheezing: is it predictive of future asthma?

Objective: Increased eosinophil level in bronchoalveolar lavage fluid (BALF) characterizes asthma in school-age children and adults and has been suggested as a marker for disease severity and response to treatment. We aimed to investigate the occurrence and yield of BALF eosinophil cell count in preschool children with recurrent wheezing and its possible relation to future diagnosis of asthma. Methods: BALF was retrospectively studied in young wheezy children and its relation to asthma at age 6 years was evaluated. BALF from children aged 1-48 months (mean = 20.4) was analyzed in preschool wheezy children. Children with anatomical airway obstruction and other lower airway/lung diseases who underwent BALF served as controls. Assessment of asthma was accomplished at 6 years. Results: Eighty-two children were included. The mean age during bronchoscopy and BAL was 20.4 ± 14.4 months (range: 1-48 months). Twenty-six patients had recurrent preschool wheezing, 13 anatomical airway obstruction and 43 had other lower airways/lung diseases. Groups were comparable for age during bronchoscopy and gender. No difference was found between groups for any of the BALF cell types. Eosinophils were very low in all three groups [mean (interquartile range): 0 (0-0.4), 0 (0-0.8), and 0.4 (0-1), respectively, p = 0.25]. No difference in eosinophil levels during bronchoscopy was found between asthmatic children to non-asthmatic as defined at age 6 years. Conclusions: Wheezing in preschool children is not associated with increased BALF eosinophils; hence, at this age, the diagnostic yield of BALF for cell count analysis for diagnosing asthma is limited and is not routinely indicated.

Early Lung Function and Future Asthma

Asthmatic adults with lower lung function have been described as having had this worse condition early in life. Lung function is reduced in children with persistent asthma and continues low throughout adult life. The challenge is to know if impaired lung function is a risk factor of asthma, as a consequence of special congenital characteristics of the airways, or whether asthmatic patients suffer a loss in lung function as early as 9 years of age as a consequence of very precocious remodeling of the airways. The loss is so early in life that it is probably a congenital characteristic, however there is not a cut-off point with clinical interest to predict risk of asthma later in life. There are contradictory results regarding whether asthmatic children lose lung function as a consequence of the airway remodeling by the illness itself. This aspect seemed to be shown for children at risk-the offspring of asthmatic mothers. The early BHR seems to be very frequent even in healthy infants, but is probably not a risk factor for asthma years later; except in the offspring of asthmatic mothers in which it has been shown. There are still many uncertainties in this field; so, more research is needed in order to better understand the pathophysiology of asthma, the early risk factors and to design new therapeutic targets and early interventions to change the natural history of the disease.

Asthma in the Preschool Age Child

Wheeze in preschool children (5 years of age and younger) is common. The majority of severe episodes are triggered by viral colds. Unlike atopic asthma in adults and young people, the underlying pathology of this condition is poorly understood, and the label of “preschool wheeze” should therefore not be regarded as a diagnosis but a description of symptoms. It is important to consider other causes of wheeze, but, for the most part, serious conditions such as cystic fibrosis and foreign body aspiration are associated with atypical features on careful history and examination. There remain significant uncertainties about the optimal management of children with this condition. Short-acting bronchodilators are indicated for the acute treatment of wheeze, and current evidence suggests that daily inhaled corticosteroid therapy is an effective preventive therapy, at least in a subgroup of children. Some trials suggest that preemptive therapy with inhaled corticosteroids may be as effective as regular inhaled corticosteroids. Since wheeze is intermittent for the majority of children, preemptive therapy is a logical approach. However, more studies are needed to confirm whether preemptive inhaled corticosteroids are as, or more, effective than regular preventer therapy.

Pediatric pulmonology year in review 2017: Part 1

Pediatric Pulmonology publishes original research, case reports and review articles on topics related to a wide range of children's respiratory disorders. In this article (Part 1 of a series), we summarize the past year's publications in our major topic areas, as well as selected literature in these areas from other journals. In Part 1, we review selected articles on diagnostic testing/endoscopy, respiratory complications of neuromuscular disorders, and rare lung diseases.

Associations between patient clinical characteristics and the presence of cytomegalovirus DNA in the bronchoalveolar lavage fluid of children with recurrent wheezing

BACKGROUND

This study aimed to investigate the occurrence of Cytomegalovirus (CMV) DNA in the Bronchoalveolar lavage fluid (BALF) of children with recurrent wheezing and to identify associations with certain patient clinical characteristics.

METHODS

In this cross-sectional study, pediatric patients (age < 36 months) admitted to Soochow University Hospital with recurrent wheezing (≥ 4 episodes of wheezing per year) were enrolled in the study. Cytomegalovirus DNA from their BALF was detected by real-time PCR. Subpopulations of blood immunoglobulins and T lymphocytes were quantified. The clinical characteristics of patients with and without BALF CMV DNA were compared. Comparisons of non-normally distributed continuous variables between groups were made using the Mann-Whitney U-test. Comparisons of frequency distributions were made using the Chi-squared test. Spearman's rank correlation coefficient was used to evaluate correlations between the number of CMV DNA copies and continuous variables.

RESULTS

A total of 111 patients aged 4 to 36 months (median 14.0 (IQR 8.0-22.0) months) were enrolled on to the study. Cytomegalovirus DNA was detected in 51.4% of patients (n = 111) with recurrent wheeze and was more prevalent among those aged 12 to 36 months with a positive modified asthma predictive index (mAPI) (n = 38, median 23.5 (IQR 19.7-31.2) months) than in those of the same age group with a negative mAPI (n = 25, median 15.0 (IQR 13.0-19.0) months) (57.9% vs. 20.0%, p = 0.003). Bronchoalveolar lavage fluid CMV DNA copy number [median 7560 (IQR 1200-71,150) copies/mL] was positively correlated with the duration of hospitalization (r = 0.33, p = 0.013), and negatively correlated with patient age (r = - 0.41, p = 0.002) and the percentage of BALF eosinophils (r = - 0.38, p = 0.004).

CONCLUSIONS

CMV infection or reactivation in children with recurrent wheeze is associated with certain clinical characteristics, including younger age and lower levels of BALF eosinophils. Higher CMV DNA copy numbers were associated with a longer duration of hospitalization. Further studies are needed to address whether specific antiviral treatment could be beneficial for BALF CMV positive patients.

Trans-nasal flexible bronchoscopy in wheezing children: Diagnostic yield, impact on therapy, and prevalence of laryngeal cleft

AIM

Persistent or recurrent wheezing is a common indication for flexible bronchoscopy, as anatomic and infectious or inflammatory changes are highly prevalent. We sought to evaluate the prevalence of anatomic, infectious, and inflammatory disease in a cohort of children undergoing flexible bronchoscopy for wheezing or poorly controlled asthma.

METHODS

We retrospectively reviewed all children <18 years old who underwent flexible bronchoscopy at our center from October 29, 2012-December 31, 2016 for the primary or secondary indication of wheezing (persistent, frequently recurring, or atypical) or poorly controlled asthma.

RESULTS

A total of 101 procedures were identified in 94 patients, aged 3 months to 18 years. Potential anatomic causes for wheezing identified in 45.7% of patients and inflammatory changes in 49.5% of procedures. This included the identification of a laryngeal cleft in 17% for which half required medical or surgical management. Tracheobronchomalacia was the most commonly identified anatomic lesion. Thirty children from this cohort had poorly controlled asthma. Among this subgroup, 54% had increased neutrophils on BAL and 30% had an anatomic contributor to wheezing, including one with a laryngeal cleft. Based on findings from flexible bronchoscopy, management changes made in 63.8% of patients. This included medication changes in 54 and surgical intervention in 9.

DISCUSSION

We conclude that transnasal flexible bronchoscopy has high yield in children with recurrent, persistent, or atypical wheezing and those with poorly controlled asthma. Laryngeal cleft has a reasonably high prevalence that warrants specific evaluation in this population.

Approaching Current and New Drug Therapies for Pediatric Asthma

As new therapies for pediatric asthma are approved by the Food and Drug Administration, clinicians should be aware of their benefits and limitations. Accompanying these therapies are potential obstacles, including the delivery of inhaled therapies and age-specific issues regarding implementation and adherence. New insights are being added to well-established controller medications, including inhaled corticosteroids and long-acting β-agonists, while new medications previously approved in adults, including tiotropium and biologics, are now being evaluated for use in children. These drugs can be useful additive therapies to treat patients who are currently not responding to guidelines-based therapy.

Wheezing in Infancy: An Overview of Recent Literature

PURPOSE OF REVIEW

Wheezing in infancy is a common presentation with many potential causes. In writing this review, we sought to summarize the newest recommendations and testing available for the more common etiologies of wheezing.

RECENT FINDINGS

Regarding the diagnosis of asthma, the modified asthma predictive index has recently been established as a useful predictive tool. Non-breath held multidetector CT with 3D volume rendering airway images is also a newer helpful diagnostic tool for tracheomalacia due to ease of use and its 100% positive predictive value. We found vaccines have greatly reduced the prevalence of epiglottitis, while advances in surgery are improving outcomes in infants with vascular rings. Wheezing in infants is a common problem with an extensive differential diagnosis from relatively benign to life threatening. To prevent over-looking a diagnosis that potentially requires surgical correction or emergent care, we recommend a structured approach to the history and physical exam with targeted testing directed towards the most likely diagnoses as outlined in this review.

A Comparative Analysis of Pulmonary and Critical Care Medicine Guideline Development Methodologies

RATIONALE

The Institute of Medicine (IOM) standards for guideline development have had unintended negative consequences. A more efficient approach is desirable.

OBJECTIVES

To determine whether a modified Delphi process early during guideline development discriminates recommendations that should be informed by a systematic review from those that can be based upon expert consensus.

METHODS

The same questions addressed by IOM-compliant pulmonary or critical care guidelines were addressed by expert panels using a modified Delphi process, termed the Convergence of Opinion on Recommendations and Evidence (CORE) process. The resulting recommendations were compared. Concordance of the course of action, strength of recommendation, and quality of evidence, as well as the duration of recommendation development, were measured.

MEASUREMENTS AND MAIN RESULTS

When 50% agreement was required to make a recommendation, all questions yielded recommendations, and the recommended courses of action were 89.6% concordant. When 70% agreement was required, 17.9% of questions did not yield recommendations, but for those that did, the recommended courses of action were 98.2% concordant. The time to completion was shorter for the CORE process (median, 19.3 vs. 1,309.0 d; P = 0.0002).

CONCLUSIONS

We propose the CORE process as an early step in guideline creation. Questions for which 70% agreement on a recommendation cannot be achieved should go through an IOM-compliant process; however, questions for which 70% agreement on a recommendation can be achieved can be accepted, avoiding a lengthy systematic review.

Clinical potential for imaging in patients with asthma and other lung disorders

The ability of lung imaging to phenotype patients, determine prognosis, and predict response to treatment is expanding in clinical and translational research. The purpose of this perspective is to describe current imaging modalities that might be useful clinical tools in patients with asthma and other lung disorders and to explore some of the new developments in imaging modalities of the lung. These imaging modalities include chest radiography, computed tomography, lung magnetic resonance imaging, electrical impedance tomography, bronchoscopy, and others.