The heterogeneity of viral bronchiolitis: A lack of universal consensus definitions

Asthmalitis? Diagnostic Variability of Asthma and Bronchiolitis in Children <24 Months

BACKGROUND AND OBJECTIVES

Bronchiolitis and asthma have similar acute clinical presentations in young children yet have opposing treatment recommendations. We aimed to assess the role of age and other factors in the diagnosis of bronchiolitis and asthma in children <24 months of age.

METHODS

We conducted a retrospective cross-sectional analysis of the Pediatric Health Information System database. We included children aged <2 years diagnosed with bronchiolitis, asthma, wheeze, or bronchospasm in emergency department or hospital encounters from 2017 to 2021. We described variation by age and between institutions. We used mixed-effects models to assess factors associated with a non-bronchiolitis diagnosis in children 12 to 23 months of age.

RESULTS

We included 554 158 encounters from 42 hospitals. Bronchiolitis made up 98% of encounters for children <3 months of age, whereas asthma diagnoses increased with age and were included in 44% of encounters at 23 months of age. Diagnosis patterns varied widely between hospitals. In children 12 to 23 months of age, the odds of a non-bronchiolitis diagnosis increased with month of age (odds ratio [OR] 1.13, 95% confidence interval [CI] 1.12-1.13), male sex (OR 1.37, 95% CI 1.35-1.40), non-Hispanic Black race (OR 1.54, 95% CI 1.50-1.58), number of previous encounters (OR 2.73, 95% CI 2.61-2.86, for 3 or more encounters), and previous albuterol use (OR 2.24, 95% CI 2.16-2.32).

CONCLUSIONS

Non-bronchiolitis diagnoses and the use of inhaled bronchodilators and systemic steroids for acute wheezing respiratory illness increase with month of age in children aged 0 to 23 months. Better definitions of clinical phenotypes of bronchiolitis and asthma would allow for more appropriate treatment in acute care settings, particularly in children 12 to 23 months of age.

Nebulised 3% hypertonic saline versus 0.9% saline for treating patients hospitalised with acute bronchiolitis: protocol for a randomised, double-blind, multicentre trial

INTRODUCTION

Bronchiolitis is an acute viral infection of the lower respiratory tract. It is most commonly caused by respiratory syncytial virus. Being a common reason for hospitalisation, it affects 13-17% of all hospitalised children younger than 2 years. Only supportive therapy, including suctioning nasal secretions, water-electrolyte balance maintenance and oxygen supplementation when needed, is recommended. However, non-evidence-based diagnostic and therapeutic approaches, including the use of inhaled bronchodilators, nebulised epinephrine, and nebulised and systemic steroids, are common. The inhalation of 3% hypertonic saline is not recommended in bronchiolitis management. However, a recently published meta-analysis revealed that the inhalation of hypertonic saline can reduce the risk of hospitalisation for outpatients with bronchiolitis, while resulting in a shorter length of hospital stay and reduced severity of respiratory distress for inpatients, although the evidence is of low certainty. We aim to assess the efficacy of nebulised hypertonic saline for the treatment of children hospitalised with bronchiolitis.

METHODS AND ANALYSIS

This will be a randomised, double-blinded, parallel-group, controlled trial. Children younger than 2 years who are hospitalised due to bronchiolitis will be recruited from at least three paediatric departments in Poland. Bronchiolitis is defined as an apparent viral respiratory tract infection associated with airway obstruction that is manifested by at least one of following symptoms: tachypnoea, increased respiratory effort, crackles and/or wheezing. A total of 140 children will be randomised (1:1) to receive either hypertonic saline nebulisation (5 mL, three times a day) or normal saline at the same dose. The primary outcome measure will be the duration of hospitalisation.

ETHICS AND DISSEMINATION

The Bioethics Committee of the Lower Silesia Medical Chamber in Wroclaw approved the study protocol (4/PNDR/2023). Caregivers will receive oral and written information about the study and written informed consent will be obtained by the study physicians. The findings of the study will be submitted to a peer-reviewed journal, and abstracts will be submitted to relevant national and international conferences.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov Registry (NCT06069336).

GEMA 5.3. Spanish Guideline on the Management of Asthma

The Spanish Guideline on the Management of Asthma, better known by its acronym in Spanish GEMA, has been available for more than 20 years. Twenty-one scientific societies or related groups both from Spain and internationally have participated in the preparation and development of the updated edition of GEMA, which in fact has been currently positioned as the reference guide on asthma in the Spanish language worldwide. Its objective is to prevent and improve the clinical situation of people with asthma by increasing the knowledge of healthcare professionals involved in their care. Its purpose is to convert scientific evidence into simple and easy-to-follow practical recommendations. Therefore, it is not a monograph that brings together all the scientific knowledge about the disease, but rather a brief document with the essentials, designed to be applied quickly in routine clinical practice. The guidelines are necessarily multidisciplinary, developed to be useful and an indispensable tool for physicians of different specialties, as well as nurses and pharmacists. Probably the most outstanding aspects of the guide are the recommendations to: establish the diagnosis of asthma using a sequential algorithm based on objective diagnostic tests; the follow-up of patients, preferably based on the strategy of achieving and maintaining control of the disease; treatment according to the level of severity of asthma, using six steps from least to greatest need of pharmaceutical drugs, and the treatment algorithm for the indication of biologics in patients with severe uncontrolled asthma based on phenotypes. And now, in addition to that, there is a novelty for easy use and follow-up through a computer application based on the chatbot-type conversational artificial intelligence (ia-GEMA).

Factors associated with salbutamol overuse in bronchiolitis

Numerous studies have shown that quality improvement methods can reduce the use of medications in the management of bronchiolitis. Our objective is to identify factors related to the overuse of salbutamol in the treatment of bronchiolitis before and after an improvement initiative. Observational study of sociodemographic and clinical factors associated with the use of salbutamol in children diagnosed with bronchiolitis. This was a secondary analysis of a prospective cohort study conducted at 135 primary care (PC) centers and eight pediatric emergency departments (ED) in the Osakidetza/Basque Health Service (Spain) in two epidemic seasons between which a bronchiolitis integrated care pathway (BICP) had been implemented: pre-intervention season from October 2018 to March 2019 and post-intervention season from October 2019 to March 2020. Generalized linear mixed models were used to estimate association of studied variables on use of salbutamol over the two seasons. Four thousand one hundred thirty-four ED attendances and 8573 PC visits were included, of which 1936 (46.8%). And 4067 (47.4%) occurred in the post-intervention period respectively. Six independent risk factors were associated with overuse of salbutamol in both seasons: age ≥ 1 year, aOR 2.32 (2.01 to 2.68) in PC centers, and aOR 6.84 (4.98 to 9.39) in EDs; being seen in the last third of the bronchiolitis season, aOR 1.82 (1.51 to 2.18) in PC centers and aOR 1.78 (1.19 to 2.64) in EDs; making more than one visit to the PC center, aOR 4.18 (3.32 to 5.27) or the ED, aOR 2.06 (1.59 to 2.66); being seen by a general practitioner, aOR 1.97 (1.58 to 2.46) in PC centers; and having a more severe episode, aOR 3.01 (1.89 to 4.79) in EDs.     Conclusion:There are factors associated with salbutamol overuse in children diagnosed with bronchiolitis in PC and emergency settings that persist after the deployment of quality improvement initiatives. What is Known: • Quality improvement initiatives have been shown to decrease the use of non-evidence-based treatments and testing in bronchiolitis. • The magnitude and pattern of change in the use of medications linked to the quality improvement initiatives are not uniform across the same health service. What is New: • Children diagnosed with bronchiolitis ≥ 1 year of age, seen in the last third of the bronchiolitis season, attending more than once, treated by a general practitioner, and/or with more severe episodes are more likely to be treated with salbutamol. • These factors may remain present despite the implementation of improvement initiatives focused on reducing the use of medications in the management of bronchiolitis.

Unusual local epidemic of paediatric respiratory syncytial virus during a time of global pandemic

BACKGROUND

Western Australia (WA) public health measures to eradicate SARS-CoV-2 resulted in a secondary reduction in paediatric respiratory syncytial virus (RSV) admissions. Following an absent expected 2020 winter peak, RSV-positive admissions surged during the summer of 2020.

AIM

This report examines the number of RSV-positive admissions and severities across 36 months to better understand this out-of-season epidemic.

METHODS

A retrospective observational study was performed assessing the number and severity of RSV-related respiratory hospitalisations at a peripheral paediatric centre from March 2018 to February 2021. Data were extracted from the hospital clinical database.

RESULTS

The total number of included participants was n = 294. The total number of RSV hospitalisations in SY (study year) 2018 (March 2018 to February 2019), SY 2019 (March 2019 to February 2020) and SY 2020 (March 2020 to February 2021) was 67, 98 and 129, respectively. Prior to SARS-CoV-2, RSV hospitalisations were highest during the winter months. In SY 2020, there were 0 RSV hospitalisations during winter, while 101 admissions in the following summer season. The proportion of admissions requiring respiratory support was significantly reduced in SY 2020 (34.1%) compared to SY 2018 (46.9%, P = 0.050) and SY 2019 (55.2%, P = 0.004). The median length of stay (LOS) in 2020 was 2.0 which was significantly reduced from 2018 and 2019 which was 3.0, P = 0.001; and 3.0, P < 0.001, respectively.

CONCLUSION

Following a period of RSV absence, there was an unprecedented surge in admission, however, with lower severity and shorter LOS.

Respiratory Syncytial Virus is the Most Common Causative Agent of Viral Bronchiolitis in Young Children: An Updated Review

BACKGROUND

Viral bronchiolitis is a common condition and a leading cause of hospitalization in young children.

OBJECTIVE

This article provides readers with an update on the evaluation, diagnosis, and treatment of viral bronchiolitis, primarily due to RSV.

METHODS

A PubMed search was conducted in December 2021 in Clinical Queries using the key terms "acute bronchiolitis" OR "respiratory syncytial virus infection". The search included clinical trials, randomized controlled trials, case control studies, cohort studies, meta-analyses, observational studies, clinical guidelines, case reports, case series, and reviews. The search was restricted to children and English literature. The information retrieved from the above search was used in the compilation of this article.

RESULTS

Respiratory syncytial virus (RSV) is the most common viral bronchiolitis in young children. Other viruses such as human rhinovirus and coronavirus could be etiological agents. Diagnosis is based on clinical manifestation. Viral testing is useful only for cohort and quarantine purposes. Cochrane evidence-based reviews have been performed on most treatment modalities for RSV and viral bronchiolitis. Treatment for viral bronchiolitis is mainly symptomatic support. Beta-agonists are frequently used despite the lack of evidence that they reduce hospital admissions or length of stay. Nebulized racemic epinephrine, hypertonic saline and corticosteroids are generally not effective. Passive immunoprophylaxis with a monoclonal antibody against RSV, when given intramuscularly and monthly during winter, is effective in preventing severe RSV bronchiolitis in high-risk children who are born prematurely and in children under 2 years with chronic lung disease or hemodynamically significant congenital heart disease. Vaccines for RSV bronchiolitis are being developed. Children with viral bronchiolitis in early life are at increased risk of developing asthma later in childhood.

CONCLUSION

Viral bronchiolitis is common. No current pharmacologic treatment or novel therapy has been proven to improve outcomes compared to supportive treatment. Viral bronchiolitis in early life predisposes asthma development later in childhood.

Diagnosis and management of asthma in infants and preschoolers

Asthma is one of the most common chronic disease affecting children, and it often starts in infancy and preschool years. In previous birth cohorts, frequent wheezing in early life was associated with the development of asthma in later childhood and reduced lung function persisting into adulthood. Preschool wheezing is considered an umbrella term for distinctive diseases with different clinical features (phenotypes), each of which may be related to different underlying pathophysiologic mechanisms (endotypes). The classification of phenotypes of early wheezing is needed to identify children at high risk for developing asthma later who might benefit from early intervention. However, diagnosis of asthma in infants and preschoolers is particularly difficult because objective lung function tests cannot be performed and definitive biomarkers are lacking. Moreover, management of early asthma is challenging because of its different phenotypic presentations. Many prediction models and asthma guidelines have been developed to provide useful information for physicians to assess young children with recurrent wheezing and manage them appropriately. Many recent studies have investigated the application of personalized medicine for early asthma by identifying specific phenotypes and biomarkers. Further researches, including genetic and molecular studies, are needed to establish a clear definition of asthma and develop more targeted therapeutic approaches in this age group.

Bronchiolitis therapies and misadventures

Viral bronchiolitis, which is most commonly caused by an infection with the respiratory syncytial virus (RSV), can lead to respiratory difficulties in young children which may require hospitalization. Despite years of research and medical trials, the mainstay of bronchiolitis treatment remains supportive only. This review provides an overview of the history of different treatments for bronchiolitis, including those that failed, as well as new therapies that are under study. Future studies for the treatment of bronchiolitis should consider different age-groups, important subgroups (i.e., those with a prior history of wheezing, those with a family history of asthma and those with non-RSV viral etiologies) whose response to treatment may differ from that of the composite group.

Bronchiolitis

Viral bronchiolitis is the most common cause of admission to hospital for infants in high-income countries. Respiratory syncytial virus accounts for 60-80% of bronchiolitis presentations. Bronchiolitis is diagnosed clinically without the need for viral testing. Management recommendations, based predominantly on high-quality evidence, advise clinicians to support hydration and oxygenation only. Evidence suggests no benefit with use of glucocorticoids or bronchodilators, with further evidence required to support use of hypertonic saline in bronchiolitis. Evidence is scarce in the intensive care unit. Evidence suggests use of high-flow therapy in bronchiolitis is limited to rescue therapy after failure of standard subnasal oxygen only in infants who are hypoxic and does not decrease rates of intensive care unit admission or intubation. Despite systematic reviews and international clinical practice guidelines promoting supportive rather than interventional therapy, universal de-implementation of interventional care in bronchiolitis has not occurred and remains a major challenge.

Lung function at school age in infants with lower respiratory tract infections with and without wheezing: A birth cohort study

OBJECTIVE

To evaluate the relationship between lower respiratory tract infections (LRTI), in the first 2 years of life and lung function at school age in the Piccolipiù birth cohort (Italy).

METHODS

Data on LRTI (doctor diagnosis of bronchitis, bronchiolitis, pneumonia) and wheezing (≥3 episodes or a diagnosis of asthmatic bronchitis) in the first 2 years of life were obtained from parental questionnaires. Lung function was assessed at 7 years by spirometry and forced volume vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1/FVC, forced expiratory flow between 25% and 75%, and at 75% of FVC (FEF_25-75 and FEF₇₅ ) were reported as Z-scores. The associations between LRTI and spirometric variables were estimated with linear regression models.

RESULTS

Among 877 children studied, 22.1% had LRTI only, 5.4% wheezing only, 13.2% had both, and 59.3% had neither LRTI nor wheezing. Children with LRTI had lower FVC and FEV₁ than children without (Z-score differences: -0.18 [95% confidence intervals: -0.31; -0.06] and -0.15 [-0.27; -0.03]). When children were stratified by history of both LRTI and wheezing, there was no association between LRTI only and spirometric values. Conversely, having had both LRTI and wheezing was inversely associated with all lung function measures: Z-score differences of -0.24 (-0.42; -0.07); -0.42 (-0.59; -0.24); -0.25 (-0.41; -0.08); -0.37 (-0.54; -0.21); -0.30 (-0.46; -0.14) for FVC, FEV_1, FEV₁ /FVC, FEF_25-75 and FEF_75, respectively.

CONCLUSION

Infants with wheezing and LRTI, but not those with LRTI only, had reduced lung function at school-age.

Severe bronchiolitis profiles and risk of asthma development in Finnish children

BACKGROUND

Recent studies support the existence of several entities under the clinical diagnosis of bronchiolitis. Among infants with severe bronchiolitis, distinct profiles have been differentially associated with development of recurrent wheezing by age 3 years. However, their associations with actual asthma remain unclear.

OBJECTIVE

Our aim was to study the association between severe bronchiolitis profiles identified by using a clustering approach and childhood asthma.

METHODS

Among 408 children (aged <2 years) hospitalized with bronchiolitis in Finland (in 2008-2010), latent class analysis identified 3 bronchiolitis profiles: profile A (47%), characterized by history of wheezing and/or eczema, wheezing during acute illness, and rhinovirus infection; profile BC (38%), characterized by severe illness and respiratory syncytial virus infection; and profile D (15%), characterized by the least severely ill children, including mostly children without wheezing and with rhinovirus infection. The children were followed by questionnaire 4 years later (86% [n = 348]) and through a nationwide social insurance database 7 years later (99% [n = 403]). Current asthma at the 4- and 7-year follow-ups was defined by regular use (according to parental report and medical records) or purchase (according to the social insurance database) of asthma control medication.

RESULTS

Compared with risk of current asthma associated with profile BC, we observed increased risk of current asthma associated with profile A both at the 4-year follow-up (age- and sex-adjusted odds ratio = 2.42 [95% CI = 1.23-4.75]) and at the 7-year follow-up (age- and sex-adjusted odds ratio = 3.14 [95% CI = 1.33-7.42]). No significant difference in asthma risk was observed between profile D and profile BC.

CONCLUSION

These longitudinal results provide further support for an association between a distinct severe bronchiolitis profile (characterized by a history of wheezing and/or eczema and rhinovirus infection) and risk of development childhood asthma.

Bronchiolitis phenotypes identified by latent class analysis may influence the occurrence of respiratory sequelae

BACKGROUND

The heterogeneity of bronchiolitis may imply or reflect a different predisposition to respiratory sequelae.

OBJECTIVE

Our aim was to investigate whether, among infants hospitalized with bronchiolitis, different clinical profiles extracted by latent class analysis (LCA) are associated with different risks of wheezing.

METHODS

Over 15 consecutive epidemic seasons (2004-2019), we prospectively enrolled infants <1 year hospitalized for the first episode of bronchiolitis in a single tertiary hospital. A detailed clinical questionnaire was filled for each infant. LCA was applied to differentiate bronchiolitis phenotypes, and after hospital discharge, a phone interview was performed annually to record the presence of wheezing episodes. Adjusted multivariate regression analyses were run to investigate the risk of wheezing during 7 years follow-up according to clinical phenotypes.

RESULTS

LCA performed on 1312 infants resulted in a three-class model. Profile 1 (65.5%): moderate bronchiolitis; Profile 2 (6.1%): severe bronchiolitis; and Profile 3(28.4%): bronchiolitis infants with high eosinophils blood count. At 1 year of follow up, about 50% of children presented wheezing in each profile. Compared to Profile 1, the adjusted odds ratio (OR) of having wheezing episodes was significantly higher in Profile 2 at 2, 3, and 4 years of follow-up. At 7 years, Profile 3 had an adjusted OR = 2.58, higher than Profile 2 (adjusted OR = 2.29).

CONCLUSIONS

LCA clearly identified a "moderate", "severe," and "high eosinophils blood count" bronchiolitis. During the first 4 years after bronchiolitis, the "severe" profile showed the higher risk of wheezing, but after 7 years this risk seems higher in the "high eosinophils blood count" group.

Racial and ethnic disparities in bronchiolitis management in freestanding children's hospitals

OBJECTIVE

Variation in bronchiolitis management by race and ethnicity within emergency departments (EDs) has been described in single-center and prospective studies, but large-scale assessments across EDs and inpatient settings are lacking. Our objective is to describe the association between race and ethnicity and bronchiolitis management across 37 U.S. freestanding children's hospitals from 2015 to 2018.

METHODS

Using the Pediatric Health Information System, we analyzed ED and inpatient visits from November 2015 to November 2018 of children with bronchiolitis 3 to 24 months old. Rates of use for specific diagnostic tests and therapeutic measures were compared across the following race/ethnicity categories: 1) non-Hispanic White (NHW), 2) non-Hispanic Black (NHB), 3) Hispanic, and 4) other. The subanalyses of ED patients only and children < 1 year old were performed. Mixed-effect logistic regression was performed to compare the adjusted odds of receiving specific test/treatment using NHW children as the reference group.

RESULTS

A total of 134,487 patients met inclusion criteria (59% male, 28% NHB, 26% Hispanic). Adjusted analysis showed that NHB children had higher odds of receiving medication associated with asthma (odds ratio [OR] = 1.27, 95% confidence interval [CI] = 1.22 to 1.32) and lower odds of receiving diagnostic tests (blood cultures, complete blood counts, viral testing, chest x-rays; OR = 0.78, 95% CI = 0.75 to 0.81) and antibiotics (OR = 0.58, 95% CI = 0.52 to 0.64) than NHW children. Hispanic children had lower odds of receiving diagnostic testing (OR = 0.94, 95% CI = 0.90 to 0.98), asthma-associated medication (OR = 0.92, 95% CI = 0.88 to 0.96), and antibiotics (OR = 0.74, 95% CI = 0.66 to 0.82) compared to NHW children.

CONCLUSION

NHB children more often receive corticosteroid and bronchodilator therapies; NHW children more often receive antibiotics and chest radiography. Given that current guidelines generally recommend supportive care with limited diagnostic testing and medical intervention, these findings among NHB and NHW children represent differing patterns of overtreatment. The underlying causes of these patterns require further investigation.

Quality Initiative to Reduce High-Flow Nasal Cannula Duration and Length of Stay in Bronchiolitis

OBJECTIVES

High-flow nasal cannula (HFNC) use in bronchiolitis may prolong length of stay (LOS) if weaned more slowly than medically indicated. We aimed to reduce HFNC length of treatment (LOT) and inpatient LOS by 12 hours in 0- to 18-month-old patients with bronchiolitis on the pediatric hospital medicine service.

METHODS

After identifying key drivers of slow weaning, we recruited a multidisciplinary "Wean Team" to provide education and influence provider weaning practices. We then implemented a respiratory therapist-driven weaning protocol with supportive sociotechnical interventions (huddles, standardized orders, simplification of protocol) to reduce LOT and LOS and promote sustainability.

RESULTS

In total, 283 patients were included: 105 during the baseline period and 178 during the intervention period. LOT and LOS control charts revealed special cause variation at the start of the intervention period; mean LOT decreased from 48.2 to 31.2 hours and mean LOS decreased from 84.3 to 60.9 hours. LOT and LOS were less variable in the intervention period compared with the baseline period. There was no increase in PICU transfers or 72-hour return or readmission rates.

CONCLUSIONS

We reduced HFNC LOT by 17 hours and LOS by 23 hours for patients with bronchiolitis via multidisciplinary collaboration, education, and a respiratory therapist-driven weaning protocol with supportive interventions. Future steps will focus on more judicious application of HFNC in bronchiolitis.

sRAGE as severe acute bronchiolitis biomarker, prospective observational study

INTRODUCTION AND OBJECTIVES

Acute bronchiolitis (AB) is the leading cause of hospitalization in infants and around 5% require intensive care treatment. Early identification of children diagnosed with AB at a high risk of severe progression is of great interest. The receptor for advanced glycation end products (RAGE), highly expressed in lung tissue, regulates immune responses and inflammation, and its soluble form, sRAGE, is believed to have an anti-inflammatory role. We hypothesized serum sRAGE might be a major determinant of AB severity and prognosis. This study was conducted to measure serum sRAGE in infants with severe AB and to assess its correlation with clinical severity, immediate complications, and outcome.

METHODS

Single-center, prospective, observational study of hospitalized children with severe bronchiolitis admitted to the Pediatric Intensive Care Unit (PICU), from September 2015 to September 2016.

RESULTS

A total of 52 children and 27 controls were included. The cases age ranged from 11 days to 21 months, resulting in a significant age difference with controls (11.85 vs 4.84 months, P < .01). Serum levels of sRAGE were lower but not significant in severe AB patients than in controls (1350.93 vs 1450.42 pg/mL; P = .399). No correlation was found between serum sRAGE and causative viruses, clinical symptoms, Wood-Downes score (a clinical severity score) on admission, respiratory support, or length of hospital stay. Serum sRAGE was also lower in the cases having had a previous respiratory disease (1463.84 vs 1072.43 pg/mL; P = .049). However, it was higher in patients with any lung consolidation on the chest X-ray (1584.79 vs 1131.62 pg/mL; P = .044) and weakly positively correlated with classical biomarkers (maximum C-reactive protein, +0.295, P = .034; maximum procalcitonin, +0.309; P = .029).

CONCLUSION

This single-center study reveals that sRAGE couldn't predict AB severity or outcome in children hospitalized at PICU. Nevertheless, it significantly increased in the presence of any lung consolidation and had a positive correlation with classical biomarkers. The utility of sRAGE in this population could be probably elucidated with a better understanding of AGE-RAGE axis.

Systematic review and meta-analysis of the prevalence of common respiratory viruses in children < 2 years with bronchiolitis in the pre-COVID-19 pandemic era

Introduction

The advent of genome amplification assays has allowed description of new respiratory viruses and to reconsider the role played by certain respiratory viruses in bronchiolitis. This systematic review and meta-analysis was initiated to clarify the prevalence of respiratory viruses in children with bronchiolitis in the pre-COVID-19 pandemic era.

Methods

We performed an electronic search through Pubmed and Global Index Medicus databases. We included observational studies reporting the detection rate of common respiratory viruses in children with bronchiolitis using molecular assays. Data was extracted and the quality of the included articles was assessed. We conducted sensitivity, subgroups, publication bias, and heterogeneity analyses using a random effect model.

Results

The final meta-analysis included 51 studies. Human respiratory syncytial virus (HRSV) was largely the most commonly detected virus 59.2%; 95% CI [54.7; 63.6]). The second predominant virus was Rhinovirus (RV) 19.3%; 95% CI [16.7; 22.0]) followed by Human bocavirus (HBoV) 8.2%; 95% CI [5.7; 11.2]). Other reported viruses included Human Adenovirus (HAdV) 6.1%; 95% CI [4.4; 8.0]), Human Metapneumovirus (HMPV) 5.4%; 95% CI [4.4; 6.4]), Human Parainfluenzavirus (HPIV) 5.4%; 95% CI [3.8; 7.3]), Influenza 3.2%; 95% CI [2.2; 4.3], Human Coronavirus (HCoV) 2.9%; 95% CI [2.0; 4.0]), and Enterovirus (EV) 2.9%; 95% CI [1.6; 4.5]). HRSV was the predominant virus involved in multiple detection and most codetections were HRSV + RV 7.1%, 95% CI [4.6; 9.9]) and HRSV + HBoV 4.5%, 95% CI [2.4; 7.3]).

Conclusions

The present study has shown that HRSV is the main cause of bronchiolitis in children, we also have Rhinovirus, and Bocavirus which also play a significant role. Data on the role played by SARS-CoV-2 in children with acute bronchiolitis is needed.

Review registration

PROSPERO, CRD42018116067.

[Acute viral bronchiolitis and wheezy bronchitis in children]

Akute Bronchiolitis und obstruktive Bronchitis sind im Säuglings- und Kleinkindalter sehr häufige Krankheitsbilder. Sie werden durch Viren, v. a. respiratorisches Synzytialvirus und Rhinoviren, verursacht. Risikofaktoren für schwere Verläufe sind u. a. Frühgeburtlichkeit, Tabakrauchexposition und Immundysfunktionen. Die Diagnose kann durch Anamnese und klinische Untersuchung gestellt werden; Thorax-Röntgen und Laboruntersuchungen sind in der Regel nicht notwendig. Für die akute Bronchiolitis wurden viele therapeutische Ansätze propagiert, generell empfohlen sind aber nur supportive Maßnahmen (minimales Handling, Sicherstellung ausreichender Oxygenierung und Hydratation). Routinemäßig nicht empfohlen werden u. a. Antibiotika, Bronchodilatatoren, Kortikosteroide und Leukotrienrezeptorantagonisten. Kurz wirksame β₂-Agonisten sind Therapie der 1. Wahl bei akuter obstruktiver Bronchitis. Bei häufigen und/oder schweren obstruktiven Bronchitiden kann zur Symptomkontrolle eine Therapie mit inhalativen Kortikosteroiden versucht werden. Die Entstehung von Asthma bronchiale ist jedoch durch keine medikamentöse Therapie zu verhindern.

Time to Say Goodbye to Bronchiolitis, Viral Wheeze, Reactive Airways Disease, Wheeze Bronchitis and All That

The diagnosis and management of infants and children with a significant viral lower respiratory tract illness remains the subject of much debate and little progress. Over the decades various terms for such illnesses have been in and fallen out of fashion or have evolved to mean different things to different clinicians. Terms such as "bronchiolitis," "reactive airways disease," "viral wheeze," and many more are used to describe the same condition and the same term is frequently used to describe illnesses caused by completely different dominant pathologies. This lack of clarity is due, in large part, to a failure to understand the basic underlying inflammatory and associated processes and, in part, due to the lack of a simple test to identify a condition such as asthma. Moreover, there is a lack of insight into the fact that the same pathology can produce different clinical signs at different ages. The consequence is that terminology and fashions in treatment have tended to go around in circles. As was noted almost 60 years ago, amongst pre-school children with a viral LRTI and airways obstruction there are those with a "viral bronchitis" and those with asthma. In the former group, a neutrophil dominated inflammation response is responsible for the airways' obstruction whilst amongst asthmatics much of the obstruction is attributable to bronchoconstriction. The airways obstruction in the former group is predominantly caused by airways secretions and to some extent mucosal oedema (a "snotty lung"). These patients benefit from good supportive care including supplemental oxygen if required (though those with a pre-existing bacterial bronchitis will also benefit from antibiotics). For those with a viral exacerbation of asthma, characterized by bronchoconstriction combined with impaired b-agonist responsiveness, standard management of an exacerbation of asthma (including the use of steroids to re-establish bronchodilator responsiveness) represents optimal treatment. The difficulty is identifying which group a particular patient falls into. A proposed simplified approach to the nomenclature used to categorize virus associated LRTIs is presented based on an understanding of the underlying pathological processes and how these contribute to the physical signs.

Impact of a modification of the clinical practice guide of the American Academy of Pediatrics in the management of severe acute bronchiolitis in a pediatric intensive care unit

Objective

To describe the characteristics and evolution of patients with bronchiolitis admitted to a pediatric intensive care unit, and compare treatment pre- and post-publication of the American Academy of Pediatrics clinical practice guide.

Design

A descriptive and observational study was carried out between September 2010 and September 2017.

Setting

Pediatric intensive care unit.

Patients

Infants under one year of age with severe bronchiolitis.

Interventions

Two periods were compared (2010–14 and 2015–17), corresponding to before and after modification of the American Academy of Pediatrics guidelines for the management of bronchiolitis in hospital.

Main variables

Patient sex, age, comorbidities, severity, etiology, administered treatment, bacterial infections, respiratory and inotropic support, length of stay and mortality.

Results

A total of 706 patients were enrolled, of which 414 (58.6%) males, with a median age of 47 days (IQR 25–100.25). Median bronchiolitis severity score (BROSJOD) upon admission: 9 points (IQR 7–11). Respiratory syncytial virus appeared in 460 (65.16%) patients. The first period (2010–14) included 340 patients and the second period (2015–17) 366 patients. More adrenalin and hypertonic saline nebulizations and more corticosteroid treatment were administered in the second period. More noninvasive ventilation and less conventional mechanical ventilation were used, and less inotropic support was needed, with no significant differences. The antibiotherapy rate decreased significantly (p = 0.003).

Conclusions

Despite the decrease in antibiotherapy, the use of nebulizations and glucocorticoids in these patients should be limited, as recommended by the guide.

The impact of viral bronchiolitis phenotyping: Is it time to consider phenotype-specific responses to individualize pharmacological management?

Although recent guidelines recommend a minimalist approach to bronchiolitis, there are several issues with this posture. First, there are concerns about the definition of the disease, the quality of the guidelines, the method of administration of bronchodilators, and the availability of tools to evaluate the response to therapies. Second, for decades it has been assumed that all cases of viral bronchiolitis are the same, but recent evidence has shown that this is not the case. Distinct bronchiolitis phenotypes have been described, with heterogeneity in clinical presentation, molecular immune signatures and clinically relevant outcomes such as respiratory failure and recurrent wheezing. New research is critically needed to refine viral bronchiolitis phenotyping at the molecular and clinical levels as well as to define phenotype-specific responses to different therapeutic options.

Impact of a modification of the clinical practice guide of the American Academy of Pediatrics in the management of severe acute bronchiolitis in a pediatric intensive care unit

OBJECTIVE

To describe the characteristics and evolution of patients with bronchiolitis admitted to a pediatric intensive care unit, and compare treatment pre- and post-publication of the American Academy of Pediatrics clinical practice guide.

DESIGN

A descriptive and observational study was carried out between September 2010 and September 2017.

SETTING

Pediatric intensive care unit.

PATIENTS

Infants under one year of age with severe bronchiolitis.

INTERVENTIONS

Two periods were compared (2010-14 and 2015-17), corresponding to before and after modification of the American Academy of Pediatrics guidelines for the management of bronchiolitis in hospital.

MAIN VARIABLES

Patient sex, age, comorbidities, severity, etiology, administered treatment, bacterial infections, respiratory and inotropic support, length of stay and mortality.

RESULTS

A total of 706 patients were enrolled, of which 414 (58.6%) males, with a median age of 47 days (IQR 25-100.25). Median bronchiolitis severity score (BROSJOD) upon admission: 9 points (IQR 7-11). Respiratory syncytial virus appeared in 460 (65.16%) patients. The first period (2010-14) included 340 patients and the second period (2015-17) 366 patients. More adrenalin and hypertonic saline nebulizations and more corticosteroid treatment were administered in the second period. More noninvasive ventilation and less conventional mechanical ventilation were used, and less inotropic support was needed, with no significant differences. The antibiotherapy rate decreased significantly (P=.003).

CONCLUSIONS

Despite the decrease in antibiotherapy, the use of nebulizations and glucocorticoids in these patients should be limited, as recommended by the guide.

Immune biomarkers predicting bronchiolitis disease severity: A systematic review

Bronchiolitis is one of the leading causes of hospitalisation in infancy, with highly variable clinical presentations ranging from mild disease safely managed at home to severe disease requiring invasive respiratory support. Identifying immune biomarkers that can predict and stratify this variable disease severity has important implications for clinical prognostication/disposition. A systematic literature search of the databases Embase, PubMed, ScienceDirect, Web of Science, and Wiley Online Library was performed. English language studies that assessed the association between an immune biomarker and bronchiolitis disease severity among children aged less than 24 months were included. 252 distinct biomarkers were identified across 90 studies. A substantial degree of heterogeneity was observed in the bronchiolitis definitions, measures of disease severity, and study designs. 99 biomarkers showed some significant association with disease severity, but only 18 were significant in multiple studies. However, all of these candidate biomarkers had comparable studies that reported conflicting results. Conclusion: The heterogeneity among included studies and the lack of a consistently significant biomarker highlight the need for consensus on bronchiolitis definitions and severity measures, as well as further studies assessing their clinical utility both in isolation and in combination.

Rhinovirus Type in Severe Bronchiolitis and the Development of Asthma

Background

Respiratory syncytial virus (RSV)- and rhinovirus (RV)-induced bronchiolitis are associated with an increased risk of asthma, but more detailed information is needed on virus types.

Objective

To study whether RSV or RV types are differentially associated with the future use of asthma control medication.

Methods

Over 2 consecutive winter seasons (2008-2010), we enrolled 408 children hospitalized for bronchiolitis at age less than 24 months into a prospective, 3-center, 4-year follow-up study in Finland. Virus detection was performed by real-time reverse transcription PCR from nasal wash samples. Four years later, we examined current use of asthma control medication.

Results

A total of 349 (86%) children completed the 4-year follow-up. At study entry, the median age was 7.5 months, and 42% had RSV, 29% RV, 2% both RSV and RV, and 27% non-RSV/-RV etiology. The children with RV-A (adjusted hazard ratio, 2.3; P = .01), RV-C (adjusted hazard ratio, 3.5; P < .001), and non-RSV/-RV (adjusted hazard ratio, 2.0; P = .004) bronchiolitis started the asthma control medication earlier than did children with RSV bronchiolitis. Four years later, 27% of patients used asthma control medication; both RV-A (adjusted odds ratio, 3.0; P = .03) and RV-C (adjusted odds ratio, 3.7; P < .001) etiology were associated with the current use of asthma medication. The highest risk was found among patients with RV-C, atopic dermatitis, and fever (adjusted odds ratio, 5.0; P = .03).

Conclusions

Severe bronchiolitis caused by RV-A and RV-C was associated with earlier initiation and prolonged use of asthma control medication. The risk was especially high when bronchiolitis was associated with RV-C, atopic dermatitis, and fever.

Nebulised hypertonic saline in children with bronchiolitis admitted to the paediatric intensive care unit: A retrospective study

AIM

Bronchiolitis is one of the most common lower respiratory tract infections in young children, associated with significant morbidity, but limited therapeutic options. Nebulised hypertonic saline (HS) has been a supportive treatment until current guidelines advised against its routine use. Accordingly, the University Hospital of Antwerp recently changed their policies to stop using it, allowing us to evaluate retrospectively if HS influences the duration of respiratory support. Because, to our knowledge, the effect of HS on children with severe bronchiolitis admitted to a paediatric intensive care unit (PICU) has not been studied yet, we aimed to investigate the effect in this specific patient group.

METHODS

Retrospective study including children up to the age of 2, admitted to the PICU with bronchiolitis from October 2013 until March 2016. The primary end point is the duration of respiratory support, including high flow nasal cannula, continuous positive airway pressure and invasive ventilation.

RESULTS

A total of 104 children admitted to the PICU with bronchiolitis were included, with an average age of 3.4 months. In respiratory syncytial virus (RSV) positive patients, the use of nebulised HS was correlated with a decrease in the duration of respiratory support and the length of stay by factors 0.72 (P = 0.01) and 0.81 (P = 0.04), respectively.

CONCLUSIONS

A significant correlation was found between the use of HS and a decreased duration of respiratory support and admission in the PICU in patients with RSV bronchiolitis. This finding may warrant new prospective studies investigating HS specifically in children with severe bronchiolitis.

Asthma diagnosis in infants and preschool children: a systematic review of clinical guidelines

BACKGROUND AND AIM

The definition and diagnosis of asthma are the subject of controversy that is particularly intense in the case of individuals in the first years of life, due to reasons such as the difficulty of performing objective pulmonary function tests or the high frequency with which the symptoms subside in the course of childhood. Since there is no consensus regarding the diagnosis of asthma in preschool children, a systematic review has been carried out.

MATERIALS AND METHODS

A systematic search was made of the clinical guidelines published in the last 10 years and containing information referred to the concept or diagnosis of asthma in childhood - including the first years of life (infants and preschool children). A series of key questions were established, and each selected guide was analyzed in search of answers to those questions. The review protocol was registered in the international prospective register of systematic reviews (PROSPERO), with registration number CRD42017074872.

RESULTS

Twenty-one clinical guidelines were selected: 10 general guides (children and adults), eight pediatric guides and three guides focusing on preschool children. The immense majority accepted that asthma can be diagnosed from the first years of life, without requiring pulmonary function tests or other complementary techniques. The response to treatment and the exclusion of other alternative diagnoses are key elements for establishing the diagnosis. Only one of the guides denied the possibility of diagnosing asthma in preschool children.

CONCLUSIONS

There is generalized although not unanimous agreement that asthma can be diagnosed in preschool children.

[Criteria heterogeneity in the diagnosis of acute bronchiolitis in Spain]

INTRODUCTION

Acute viral bronchiolitis (AB) is one of the most common respiratory diseases in infants. However, diagnostic criteria for AB are heterogeneous and not very well known.

OBJECTIVE

To identify the diagnostic criteria for AB used by experts and clinical paediatricians in Spain.

METHODS

Delphi study with Spanish AB experts, looking for the points of agreement about AB diagnosis. A subsequent cross-sectional study was conducted by means of an on-line questionnaire addressed to all Spanish paediatricians, reached through electronic mail messages sent by nine paediatric scientific societies. Descriptive and factorial analyses were carried out, looking for any association of diagnostic criteria with demographic or geographic variables, or with paediatric subspecialty.

RESULTS

Agreement was reached by 40 experts in many issues (first episode of respiratory distress and high respiratory frequency, diagnosis in any season of the year, and usefulness of virus identification in making diagnosis), but opposite views were maintained on key characteristics such as the maximum age for diagnosis. The on-line questionnaire was completed by 1297 paediatricians. Their diagnostic criteria were heterogeneous and strongly associated with their paediatric sub-specialty. Their agreement with the Spanish expert consensus and with international standards was very poor.

CONCLUSIONS

Diagnostic criteria for AB in Spain are heterogeneous. These differences could cause variability in clinical practice with AB patients.

Question 3: Can we diagnose asthma in children under the age of 5 years?

The diagnosis of asthma in children under five years has been controversial due to changing concepts of what true asthma is in this age group. Previous diagnostic algorithms that used clinical indices to predict the persistence of asthma symptoms or phenotypes based on asthma triggers do not predict which children will benefit from asthma medication. A pragmatic approach to asthma diagnosis in this age group is based on identifying signs and symptoms of reversible airflow obstruction and documenting their response to asthma medication. Hopefully, this approach will provide clearer guidance to clinicians and improve asthma morbidity in these young children.

Criteria heterogeneity in the diagnosis of acute bronchiolitis in Spain

INTRODUCTION

Acute viral bronchiolitis (AB) is one of the most common respiratory diseases in infants. However, diagnostic criteria for AB are heterogeneous and not very well known.

OBJECTIVE

To identify the diagnostic criteria for AB used by experts and clinical paediatricians in Spain.

METHODS

Delphi study with Spanish AB experts, looking for the points of agreement about AB diagnosis. A subsequent cross-sectional study was conducted by means of an online questionnaire addressed to all Spanish paediatricians, reached through electronic mail messages sent by nine paediatric scientific societies. Descriptive and factorial analyses were carried out, looking for any association of diagnostic criteria with demographic or geographic variables, or with paediatric subspecialty.

RESULTS

Agreement was reached by 40 experts in many issues (first episode of respiratory distress and high respiratory frequency, diagnosis in any season of the year, and usefulness of virus identification in making diagnosis), but opposite views were maintained on key characteristics such as the maximum age for diagnosis. The online questionnaire was completed by 1297 paediatricians. Their diagnostic criteria were heterogeneous and strongly associated with their paediatric sub-specialty. Their agreement with the Spanish expert consensus and with international standards was very poor.

CONCLUSIONS

Diagnostic criteria for AB in Spain are heterogeneous. These differences could cause variability in clinical practice with AB patients.

Overview of prevention and management of acute bronchiolitis due to respiratory syncytial virus

INTRODUCTION

Respiratory Syncytial Virus (RSV) is the most common cause of Acute Bronchiolitis (AVB) in infants. AVB causes significant morbidity and mortality worldwide, most deaths occurring in the developing world. AVB causes respiratory distress in infants, leading to respiratory failure in some cases. Disease is more severe in infants with risk factors, such as prematurity, chronic cardiac and lung disease and immunodeficiency. Areas covered: Despite major advances in supportive care in the developed world, which has led to a significant reduction in mortality, treatment remains symptomatic and supportive. No specific antiviral treatment has yet proven to be effective. Prevention of disease with monoclonal antibodies has proven to reduce illness severity in those with risk factors, however, this is prohibitively expensive, particularly for the developing world. Prospects for vaccine development are improving. However, because most disease is in young infants, maternal immunization is necessary. However, due to the transient nature of RSV immunity and the circulation of multiple subtypes, vaccines proven to be effective in adult challenge models have yet to be translated to protection in infants. Expert commentary: Despite advances in preventative treatments, adherence to evidence-based guidelines provides the best prospect for successful reduction in morbidity and mortality.

Bronchiolitis clinics and medical treatment

Bronchiolitis is the most common acute lower respiratory tract infection in infants and the first cause of hospitalization in this age group. Despite it has been studied for over 70 years, its management remains controversial and nowadays the treatment is only supportive. Pediatricians should be well acquainted with the clinical course of the disease. In particular, they should know that the severity of respiratory symptoms peaks between days 3-7 of the disease and dehydration is a key sign to consider for the management. In this review, we will discuss the most controversial points in the management of bronchiolitis according to six evidence-based guidelines, six clinical practice guidelines and five consensus-based reviews.

Pediatric Pulmonology year in review 2017: Part 3

Pediatric Pulmonology publishes original research, reviews, and case reports related to a wide range of children's respiratory disorders. We here summarize the past year's publications in our major topic areas, in the context of selected literature in these areas from other journals relevant to our discipline. This review (Part 3 of a 5-part series) covers selected articles on asthma, physiology/lung function testing, and respiratory infections.