Acute viral bronchiolitis in children- a very common condition with few therapeutic options

Discovery of gem-Dimethyl-hydroxymethylpyridine Derivatives as Potent Non-nucleoside RSV Polymerase Inhibitors

Respiratory syncytial virus (RSV) is an RNA virus infecting the upper and lower respiratory tract and is recognized as a major respiratory health threat, particularly to older adults, immunocompromised individuals, and young children. Around 64 million children and adults are infected every year worldwide. Despite two vaccines and a new generation monoclonal antibody recently approved, no effective antiviral treatment is available. In this manuscript, we present the medicinal chemistry efforts resulting in the identification of compound 28 (JNJ-8003), a novel RSV non-nucleoside inhibitor displaying subnanomolar activity in vitro as well as prominent efficacy in mice and a neonatal lamb models.

Sex-related immunity: could Toll-like receptors be the answer in acute inflammatory response?

An increasing number of studies have highlighted the existence of a sex-specific immune response, wherein men experience a worse prognosis in cases of acute inflammatory diseases. Initially, this sex-dependent inflammatory response was attributed to the influence of sex hormones. However, a growing body of evidence has shifted the focus toward the influence of chromosomes rather than sex hormones in shaping these inflammatory sex disparities. Notably, certain pattern recognition receptors, such as Toll-like receptors (TLRs), and their associated immune pathways have been implicated in driving the sex-specific immune response. These receptors are encoded by genes located on the X chromosome. TLRs are pivotal components of the innate immune system, playing crucial roles in responding to infectious diseases, including bacterial and viral pathogens, as well as trauma-related conditions. Importantly, the TLR-mediated inflammatory responses, as indicated by the production of specific proteins and cytokines, exhibit discernible sex-dependent patterns. In this review, we delve into the subject of sex bias in TLR activation and explore its clinical implications relatively to both the X chromosome and the hormonal environment. The overarching objective is to enhance our understanding of the fundamental mechanisms underlying these sex differences.

Clinical analysis of 114 cases of bronchiolitis in infants

BACKGROUND

Bronchiolitis is a common lower respiratory tract infection in infants and young children. Severe cases may be accompanied by obvious dyspnea and oxygen saturation decline.

AIM

To summarize the clinical features, standard diagnosis, and treatment of bronchiolitis.

METHODS

This is a retrospective analysis of 114 pediatric patients (74 males, 40 females) who were first diagnosed as having bronchioles at the Department of Pediatrics of Tongling Maternal and Child Health Hospital from January 2019 to December 2019. The clinical features, imaging features, treatment, and other clinical data were recorded and analyzed.

RESULTS

The age of onset of the disease was mainly from 1 mo to 6 mo (75.4%), and the time to hospital visit was mostly from the 2nd day to the 4th day of the course of the disease (75.4%). Lung imaging examination showed increase in lung texture, fuzzy (93.8%). The main treatment was atomization therapy: Budesonide combined with terbutaline (45.6%) and budesonide combined with salbutamol (38.5%). The average hospitalization time was 7.1 ± 2.4 d, and the overall cure rate was 94.7%. In patients without bacterial infection, the use of antibiotics significantly prolonged the length of hospital stay (7.8 ± 2.5 d vs 5.7 ± 1.8 d) and improved the cure rate (98.3% vs 87.9%, P < 0.05).

CONCLUSION

Infants with bronchiolitis are mainly male and tend to have a good prognosis. However, the unneeded use of antibiotics may prolong the length of hospital stay significantly, which imposes the burden both on the patients and hospital system.

Neutrophil-to-Lymphocyte Ratio and the Systemic Immune-Inflammation Index: Biomarkers in Infants with Bronchiolitis: a Cross-Sectional Study

The use of a novel inflammatory indicator, the systemic immune-inflammatory index (SII), in pediatric patients with bronchiolitis remains unreported. Therefore, this study investigated the relationship between the SII and the neutrophil-to-lymphocyte ratio (NLR) in patients with respiratory syncytial virus (RSV) and non-RSV bronchiolitis and clinical severity prediction. This study analyzed the data of 155 patients aged <2 years who were hospitalized for viral bronchiolitis caused by RSV and/or other viral pathogens. The SII (platelet count × [neutrophil/lymphocyte]) was calculated and compared among patients with RSV mono-infections, other viral mono-infections, and RSV co-infections. Severity was defined by the number of days of supplemental oxygen treatment. The NLR and SII were significantly higher in the non-RSV mono-infection group than in the RSV mono-infection group, and the number of days of supplemental oxygen therapy was significantly higher in the RSV mono-infection group. No significant differences in the NLR, SII, or days of supplemental oxygen therapy were found between the RSV mono-infection and RSV co-infection groups. Although patients with RSV mono-infection showed more severe clinical findings than those without non-RSV mono-infection, the NLR and SII values were significantly higher in the non-RSV mono-infection group. Therefore, the NLR and SII do not appear to be very useful measurements for determining the severity of acute bronchiolitis attacks; however, lower NLR and SII values in the RSV group compared to the non-RSV group may be potential biomarkers for RSV infection. Therefore, further studies are warranted.

Management Practices for Standard-Risk and High-Risk Patients With Bronchiolitis

OBJECTIVE

Management guidelines for bronchiolitis advocate for supportive care and exclude those with high-risk conditions. We aim to describe and compare the management of standard-risk and high-risk patients with bronchiolitis.

METHODS

This retrospective study examined patients <2 years of age admitted to the general pediatric ward with an International Classification of Diseases, 10th Revision discharge diagnosis code of bronchiolitis or viral syndrome with evidence of lower respiratory tract involvement. Patients were defined as either standard- or high-risk on the basis of previously published criteria. The frequencies of diagnostic and therapeutic interventions were compared.

RESULTS

We included 265 patients in this study (122 standard-risk [46.0%], 143 high-risk [54.0%]). Increased bronchodilator use was observed in the standard-risk group (any albuterol dosing, standard-risk 65.6%, high-risk 44.1%, P = .003). Increased steroid use was observed in the standard-risk group (any steroid dosing, standard-risk 19.7%, high-risk 14.7%, P = .018). Multiple logistic regression revealed >3 doses of albuterol, hypertonic saline, and chest physiotherapy use to be associated with rapid response team activation (odds ratio [OR] >3 doses albuterol: 8.36 [95% confidence interval (CI): 1.99-35.10], P = .048; OR >3 doses hypertonic saline: 13.94 [95% CI: 4.32-44.92], P = .001); OR percussion and postural drainage: 5.06 [95% CI: 1.88-13.63], P = .017).

CONCLUSIONS

A varied approach to the management of bronchiolitis in both standard-risk and high-risk children occurred institutionally. Bronchodilators and steroids continue to be used frequently despite practice recommendations and regardless of risk status. More research is needed on management strategies in patients at high-risk for severe disease.

Chest physiotherapy for acute bronchiolitis in paediatric patients between 0 and 24 months old

BACKGROUND

Acute bronchiolitis is the leading cause of medical emergencies during winter months in infants younger than 24 months old. Chest physiotherapy is sometimes used to assist infants in the clearance of secretions in order to decrease ventilatory effort. This is an update of a Cochrane Review first published in 2005 and updated in 2006, 2012, and 2016.

OBJECTIVES

To determine the efficacy of chest physiotherapy in infants younger than 24 months old with acute bronchiolitis. A secondary objective was to determine the efficacy of different techniques of chest physiotherapy (vibration and percussion, passive exhalation, or instrumental).

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, LILACS, Web of Science, PEDro (October 2011 to 20 April 2022), and two trials registers (5 April 2022).

SELECTION CRITERIA

Randomised controlled trials (RCTs) in which chest physiotherapy was compared to control (conventional medical care with no physiotherapy intervention) or other respiratory physiotherapy techniques in infants younger than 24 months old with bronchiolitis.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

Our update of the searches dated 20 April 2022 identified five new RCTs with 430 participants. We included a total of 17 RCTs (1679 participants) comparing chest physiotherapy with no intervention or comparing different types of physiotherapy. Five trials (246 participants) assessed percussion and vibration techniques plus postural drainage (conventional chest physiotherapy), and 12 trials (1433 participants) assessed different passive flow-oriented expiratory techniques, of which three trials (628 participants) assessed forced expiratory techniques, and nine trials (805 participants) assessed slow expiratory techniques. In the slow expiratory subgroup, two trials (78 participants) compared the technique with instrumental physiotherapy techniques, and two recent trials (116 participants) combined slow expiratory techniques with rhinopharyngeal retrograde technique (RRT). One trial used RRT alone as the main component of the physiotherapy intervention. Clinical severity was mild in one trial, severe in four trials, moderate in six trials, and mild to moderate in five trials. One study did not report clinical severity. Two trials were performed on non-hospitalised participants. Overall risk of bias was high in six trials, unclear in five, and low in six trials. The analyses showed no effects of conventional techniques on change in bronchiolitis severity status, respiratory parameters, hours with oxygen supplementation, or length of hospital stay (5 trials, 246 participants).  Regarding instrumental techniques (2 trials, 80 participants), one trial observed similar results in bronchiolitis severity status when comparing slow expiration to instrumental techniques (mean difference 0.10, 95% confidence interval (C) -0.17 to 0.37).  Forced passive expiratory techniques failed to show an effect on bronchiolitis severity in time to recovery (2 trials, 509 participants; high-certainty evidence) and time to clinical stability (1 trial, 99 participants; high-certainty evidence) in infants with severe bronchiolitis. Important adverse effects were reported with the use of forced expiratory techniques.  Regarding slow expiratory techniques, a mild to moderate improvement was observed in bronchiolitis severity score (standardised mean difference -0.43, 95% CI -0.73 to -0.13; I2 = 55%; 7 trials, 434 participants; low-certainty evidence). Also, in one trial an improvement in time to recovery was observed with the use of slow expiratory techniques. No benefit was observed in length of hospital stay, except for one trial which showed a one-day reduction. No effects were shown or reported for other clinical outcomes such as duration on oxygen supplementation, use of bronchodilators, or parents' impression of physiotherapy benefit.

AUTHORS' CONCLUSIONS

We found low-certainty evidence that passive slow expiratory technique may result in a mild to moderate improvement in bronchiolitis severity when compared to control. This evidence comes mostly from infants with moderately acute bronchiolitis treated in hospital. The evidence was limited with regard to infants with severe bronchiolitis and those with moderately severe bronchiolitis treated in ambulatory settings. We found high-certainty evidence that conventional techniques and forced expiratory techniques result in no difference in bronchiolitis severity or any other outcome. We found high-certainty evidence that forced expiratory techniques in infants with severe bronchiolitis do not improve their health status and can lead to severe adverse effects. Currently, the evidence regarding new physiotherapy techniques such as RRT or instrumental physiotherapy is scarce, and further trials are needed to determine their effects and potential for use in infants with moderate bronchiolitis, as well as the potential additional effect of RRT when combined with slow passive expiratory techniques. Finally, the effectiveness of combining chest physiotherapy with hypertonic saline should also be investigated.

UPDATE - 2022 Italian guidelines on the management of bronchiolitis in infants

Bronchiolitis is an acute respiratory illness that is the leading cause of hospitalization in young children. This document aims to update the consensus document published in 2014 to provide guidance on the current best practices for managing bronchiolitis in infants. The document addresses care in both hospitals and primary care. The diagnosis of bronchiolitis is based on the clinical history and physical examination. The mainstays of management are largely supportive, consisting of fluid management and respiratory support. Evidence suggests no benefit with the use of salbutamol, glucocorticosteroids and antibiotics with potential risk of harm. Because of the lack of effective treatment, the reduction of morbidity must rely on preventive measures. De-implementation of non-evidence-based interventions is a major goal, and educational interventions for clinicians should be carried out to promote high-value care of infants with bronchiolitis. Well-prepared implementation strategies to standardize care and improve the quality of care are needed to promote adherence to guidelines and discourage non-evidence-based attitudes. In parallel, parents' education will help reduce patient pressure and contribute to inappropriate prescriptions. Infants with pre-existing risk factors (i.e., prematurity, bronchopulmonary dysplasia, congenital heart diseases, immunodeficiency, neuromuscular diseases, cystic fibrosis, Down syndrome) present a significant risk of severe bronchiolitis and should be carefully assessed. This revised document, based on international and national scientific evidence, reinforces the current recommendations and integrates the recent advances for optimal care and prevention of acute bronchiolitis.

Systematic review and meta-analysis of efficacy and safety of continuous positive airways pressure versus high flow oxygen cannula in acute bronchiolitis

INTRODUCTION

There are a trend towards increasing use of High-Flow Nasal Cannula (HFNC), outside of paediatric intensive care unit. Give this trend is necessary to update the actual evidence and to assess available published literature to determinate the efficacy of HFNC over Continuous Positive Air Pressure (CPAP) as treatment for children with severe bronchiolitis.

METHODS

We searched MEDLINE, EMBASE, LILACS, and COCHRANE Central, and gray literature in clinical trials databases ( www.

CLINICALTRIALS

gov ), from inception to June 2022. The inclusion criteria for the literature were randomized clinical trials (RCTs) that included children < 2 years old, with acute moderate or severe bronchiolitis. All study selection and data extractions are performed independently by two reviewers.

RESULTS

The initial searches including 106 records. Only five randomized controlled trial that met the inclusion criteria were included in meta-analysis. The risk of invasive mechanical ventilation was not significantly different in CPAP group and HFNC group [OR: 1.18, 95% CI (0.74, 1.89), I² = 0%] (very low quality). The risk of treatment failure was less significantly in CPAP group than HFNC group [OR: 0.51, 95% CI (0.36, 0.75), I² = 0%] (very low quality).

CONCLUSION

In conclusion, there was no significant difference between HFNC and CPAP in terms of risk of invasive mechanical ventilation. CPAP reduces de risk of therapeutic failure with a highest risk of non severe adverse events. More trials are needed to confirm theses results.

Stability Study, Quantification Method and Pharmacokinetics Investigation of a Coumarin-Monoterpene Conjugate Possessing Antiviral Properties against Respiratory Syncytial Virus

The stability of a new coumarin derivative, agent K-142, bearing α-pinene residue and possessing antiviral activity against respiratory syncytial virus (RSV) was studied in whole mice blood in vitro, and a method for its quantification in this matrix was developed and validated. The sample preparation method was precipitation of whole blood with a mixture of 0.2 M ZnSO4 with MeOH (2:8 v/v) containing 2-adamantylamine hydrochloride as an internal standard (IS). Analysis was carried out by HPLC-MS/MS using reversed phase chromatography and a triple quadrupole mass spectrometer 6500 QTRAP (SCIEX) in multiple reaction monitoring (MRM) mode. The transitions 351.2 → 217.1 Da and 152.2 → 93.1/107.2 Da were monitored for K-142 and the IS, respectively. The method was validated in terms of selectivity, calibration curve, LLOQ, accuracy and precision, stability, recovery and carry over. The developed method was used for a pharmacokinetics study of the compound after its oral administration to mice at a dose of 20 mg/kg.

Remote, real-time expert elicitation to determine the prior probability distribution for Bayesian sample size determination in international randomised controlled trials: Bronchiolitis in Infants Placebo Versus Epinephrine and Dexamethasone (BIPED) study

Background

Bayesian methods are increasing in popularity in clinical research. The design of Bayesian clinical trials requires a prior distribution, which can be elicited from experts. In diseases with international differences in management, the elicitation exercise should recruit internationally, making a face-to-face elicitation session expensive and more logistically challenging. Thus, we used a remote, real-time elicitation exercise to construct prior distributions. These elicited distributions were then used to determine the sample size of the Bronchiolitis in Infants with Placebo Versus Epinephrine and Dexamethasone (BIPED) study, an international randomised controlled trial in the Pediatric Emergency Research Network (PERN). The BIPED study aims to determine whether the combination of epinephrine and dexamethasone, compared to placebo, is effective in reducing hospital admission for infants presenting with bronchiolitis to the emergency department.

Methods

We developed a Web-based tool to support the elicitation of the probability of hospitalisation for infants with bronchiolitis. Experts participated in online workshops to specify their individual prior distributions, which were aggregated using the equal-weighted linear pooling method. Experts were then invited to provide their comments on the aggregated distribution. The average length criterion determined the BIPED sample size.

Results

Fifteen paediatric emergency medicine clinicians from Canada, the USA, Australia and New Zealand participated in three workshops to provide their elicited prior distributions. The mean elicited probability of admission for infants with bronchiolitis was slightly lower for those receiving epinephrine and dexamethasone compared to supportive care in the aggregate distribution. There were substantial differences in the individual beliefs but limited differences between North America and Australasia. From this aggregate distribution, a sample size of 410 patients per arm results in an average 95% credible interval length of less than 9% and a relative predictive power of 90%.

Conclusion

Remote, real-time expert elicitation is a feasible, useful and practical tool to determine a prior distribution for international randomised controlled trials. Bayesian methods can then determine the trial sample size using these elicited prior distributions. The ease and low cost of remote expert elicitation mean that this approach is suitable for future international randomised controlled trials.

Trial registration

ClinicalTrials.govNCT03567473

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06240-w.

Loss of life expectancy due to respiratory infectious diseases: findings from the global burden of disease study in 195 countries and territories 1990-2017

Understanding of the patterns of and changes in mortality from respiratory infectious diseases (RID) and its contribution to loss of life expectancy (LE) is inadequate in the existing literature. With rapid sociodemographic changes globally, and the current COVID-19 pandemic, it is timely to revisit the disease burden of RID. Using the approaches of life table and cause-eliminated life table based on data from the Global Burden of Disease Study (GBD), the study analyses loss of LE due to RID in 195 countries/territories and its changes during the period 1990-2017. Results indicate that loss of LE due to RID stood at 1.29 years globally in 2017 globally and varied widely by age, gender, and geographic location, with men, elderly people, and populations in middle/low income countries/territories suffering a disproportionately high loss of LE due to RID. Additionally, loss of LE due to RID decreased remarkably by 0.97 years globally during the period 1990-2017 but increased slightly among populations older than 70 years and in many high income countries/territories. Results suggest that RID still pose a severe threat for population and public health, and that amid dramatic sociodemographic changes globally, the disease burden of RID may resurge. The study presents the first examination of the life-shortening effect of RID at the global and country/territory levels, providing new understanding of the changing disease burden of RID and shedding light on the potential consequences of the current COVID-19 pandemic.

Treatment of the most common respiratory infections in children

Acute respiratory infections are the most common group of infective diseases in the pediatric population. Although the improvement of health care and vaccination program has led to a significant reduction in the incidence of certain respiratory infections, the combination of a high prevalence in vulnerable pediatric categories and uncritical prescription of antibiotics, due to the inability to adequately distinguish between viruses and bacterial etiology, still represents a significant challenge for the public health system. In order to promote rational antibiotic therapy with an overall improvement of both diagnostic and therapeutic principles, acute respiratory diseases have been the subject of consideration in numerous publications and national guidelines. Nonspecific clinical manifestations with pathogen heterogeneity and both anatomical and physiological characteristics of the child's respiratory system during growth and development have created the need for individualized therapy. Since the guidelines emphasize the undoubtful and crucial benefits of symptomatic therapy (e.g. analgesics in acute otitis media, supplemental oxygen in lower respiratory tract infections with hypoxemia), the use of antibiotics and corticosteroids is indicated in selected cases with a severe clinical picture. The choice of antibiotic depends on the clinical condition, presumed causative agent, and local epidemiologic circumstances. Respiratory support (oxygen therapy and/or artificial ventilation) is reserved for inpatient treatment of cases with a particularly severe clinical picture and associated complications.

Monoterpene-Containing Substituted Coumarins as Inhibitors of Respiratory Syncytial Virus (RSV) Replication

Respiratory syncytial virus (RSV) is a critical cause of infant mortality. However, there are no vaccines and adequate drugs for its treatment. We showed, for the first time, that O-linked coumarin-monoterpene conjugates are effective RSV inhibitors. The most potent compounds are active against both RSV serotypes, A and B. According to the results of the time-of-addition experiment, the conjugates act at the early stages of virus cycle. Based on molecular modelling data, RSV F protein may be considered as a possible target.

Epidemiology of Bronchiolitis in Hospitalized Infants at Tawam Hospital, Al Ain, United Arab Emirates

Background

Bronchiolitis is the commonest lower respiratory tract infection, found worldwide in children < 2 years of age. Over sixty percent of cases are caused by Respiratory Syncytial Virus (RSV). The disease is known to have significant morbidity, mortality and health care costs. Its seasonal variability, manifestations and complications vary between countries. The aim of this study was to determine the epidemiological and clinical characteristics of infants hospitalized with bronchiolitis in Al Ain City, United Arab Emirates.

Methods

Retrospective observational chart review was made of an unselected cohort of infants ≤ 2 years admitted to the pediatric department of Tawam hospital over a 3-year period and discharged with the diagnosis of bronchiolitis. Epidemiological data and risk factors were analyzed.

Results

RSV was the commonest pathogen (51%). Hospitalizations occurred year-round but increased significantly in December and January. The patients' median age was 5.8 months with a male predominance (male:female ratio of 1.5:1.0). The mean age at admission was 6.6 months and presentation occurred, on average, 2.9 days after the onset of the symptoms. The majority (94%) had respiratory distress on presentation. Chest x-ray was performed in 80% of the patients. Most children received bronchodilator therapy and oxygen therapy was administered to 42%. The mean duration of hospital stay was 3 days.

Conclusion

Bronchiolitis remains a common reason for hospital admission and carries significant morbidity. RSV is the primarily responsible virus for hospital admissions and morbidity.A better understanding of the burden of bronchiolitis in our setting would enable better planning and use of hospital resources to minimize its short and long-term sequelae.

Pharmacokinetics, Safety, and Antiviral Effects of Multiple Doses of the Respiratory Syncytial Virus (RSV) Fusion Protein Inhibitor, JNJ-53718678, in Infants Hospitalized With RSV Infection: A Randomized Phase 1b Study

Background

This phase 1b study evaluated the pharmacokinetics, safety, and antiviral effects of the respiratory syncytial virus (RSV)–specific fusion inhibitor JNJ-53718678 (JNJ-8678) in hospitalized RSV-infected patients aged > 1 to ≤24 months.

Methods

Patients categorized by age (cohort 1: ≥6 to ≤24 months; cohort 2: ≥3 to < 6 months; cohort 3: > 1 to < 3 months) were randomized to oral JNJ-8678 or placebo once daily for 7 days. Dose increases followed data review committee recommendations (cohort 1: 2/6/8/9 mg/kg; cohort 2: 1.5/4.5/6 mg/kg; cohort 3: 1/3/5 mg/kg). Cohort 1 included a 9 mg/kg dose, as target exposures were not reached at lower doses. Sparse pharmacokinetic samples were assessed using population pharmacokinetics modeling. Safety was assessed by adverse events (AEs), laboratory tests, and electrocardiograms. To assess antiviral effects, RSV RNA viral load from nasal swabs was quantified over time using reverse-transcription quantitative polymerase chain reaction.

Results

Patients received JNJ-8678 (n = 37) or placebo (n = 7). Pharmacokinetic parameters were similar at the highest doses for cohorts 1–3 (area under the plasma concentration–time curve from time of administration up to 24 hours postdosing at day 7: 35 840, 34 980, and 39 627 ng × hour/mL, respectively). Two grade 3 AEs were reported (both bronchiolitis; 1 JNJ-8678, 1 placebo), reported as serious AEs; all other AEs were grade 1 or 2. Two additional serious AEs were reported (rhinitis [JNJ-8678]; pneumonia [placebo]). No deaths, grade 4 AEs, or AEs leading to discontinuation were reported. Median RSV viral load change from baseline in JNJ-8678 vs placebo by day 3 was −1.98 vs −0.32 log₁₀ copies/mL.

Conclusions

In RSV-infected infants, JNJ-8678 was well tolerated. Target exposures were reached and antiviral activity was observed.

Clinical Trials Registration

NCT02593851.

Discovery of Sisunatovir (RV521), an Inhibitor of Respiratory Syncytial Virus Fusion

RV521 is an orally bioavailable inhibitor of respiratory syncytial virus (RSV) fusion that was identified after a lead optimization process based upon hits that originated from a physical property directed hit profiling exercise at Reviral. This exercise encompassed collaborations with a number of contract organizations with collaborative medicinal chemistry and virology during the optimization phase in addition to those utilized as the compound proceeded through preclinical and clinical evaluation. RV521 exhibited a mean IC₅₀ of 1.2 nM against a panel of RSV A and B laboratory strains and clinical isolates with antiviral efficacy in the Balb/C mouse model of RSV infection. Oral bioavailability in preclinical species ranged from 42 to >100% with evidence of highly efficient penetration into lung tissue. In healthy adult human volunteers experimentally infected with RSV, a potent antiviral effect was observed with a significant reduction in viral load and symptoms compared to placebo.

Age-dependent Interactions Among Clinical Characteristics, Viral Loads and Disease Severity in Young Children With Respiratory Syncytial Virus Infection

BACKGROUND

Age-dependent differences in clinical presentation and viral loads in infants and young children with respiratory syncytial virus (RSV) infection, and their correlation with disease severity are poorly defined.

METHODS

Previously healthy children <2 years old with mild (outpatients) and severe (inpatients) RSV infection were enrolled and viral loads measured by polymerase chain reaction in nasopharyngeal swabs. Patients were stratified by age in 0-<3, 3-6 and >6-24 months, and multivariable analyses were performed to identify clinical and viral factors associated with severe disease.

RESULTS

From 2014 to 2018, we enrolled 534 children with RSV infection, 130 outpatients with mild RSV infection and 404 inpatients with severe RSV disease. Median duration of illness was 4 days for both groups, yet viral loads were higher in outpatients than in inpatients (P < 0.001). In bivariate analyses, wheezing was more frequent in outpatients of older age (>3 months) than in inpatients (P < 0.01), while fever was more common in inpatients than outpatients (P < 0.01) and its frequency increased with age. Adjusted analyses confirmed that increased work of breathing and fever were consistently associated with hospitalization irrespective of age, while wheezing in infants >3 months, and higher RSV loads in children >6-24 months were independently associated with reduced disease severity.

CONCLUSIONS

Age had a significant impact defining the interactions among viral loads, specific clinical manifestations and disease severity in children with RSV infection. These observations highlight the importance of patient stratification when evaluating interventions against RSV.

The role of peripheral type 2 innate lymphoid cells in bronchiolitis

Our aim was to detect type 2 innate lymphoid cells (ILC2s)-related cytokines of infants with bronchiolitis by using Elisa, Liquidchip technology and RT-PCR and investigated its correlation with bronchiolitis. We recruited 26 infants with bronchiolitis and 20 healthy infants as control from Xiangya Hospital. Compared to the control group, the serum levels of interleukin-5 (IL-5) [41.99 (21.11) vs 25.70 (19.64)], IL-9 [27.04 (37.51) vs 8.30 (0.54)], IL-13 [184.05 (132.81) vs 121.75 (176.13)], IL-33 [83.70 (46.69) vs 11.23 (55.31)] and thymic stromal lymphopoietin (TSLP) [31.42 (5.41) vs 28.76 (2.56)] were significantly increased in infants with bronchiolitis (P < 0.05), while the level of IgE had no significant difference between the two groups [19.05 (14.15) vs 14.85 (20.2), P > 0.05]. The mRNA expression of IL-17RB (9.83 ± 0.35 vs 9.19 ± 0.58), TSLP (16.98 ± 2.12 vs 15.07 ± 2.25), retinoid acid receptor related orphan receptor α (7.18 ± 0.71 vs 5.46 ± 1.09) and trans-acting T-cell-specific transcription factor 3 (4.86 ± 0.66 vs 4.19 ± 0.90) were significantly increased in infants with bronchiolitis versus the control group (P < 0.05), while there was no statistical significance for suppression of tumorigenicity 2 (5.59 ± 0.68 vs 5.41 ± 0.87, P > 0.05). Our findings suggested that ILC2s possibly play a specific role in immunopathology of bronchiolitis.

A Systematic Review of Clinical Practice Guidelines for the Diagnosis and Management of Bronchiolitis

BACKGROUND

Bronchiolitis is the leading cause of hospital admission for respiratory disease among infants aged <1 year. Clinical practice guidelines can benefit patients by reducing the performance of unnecessary tests, hospital admissions, and treatment with lack of a supportive evidence base. This review aimed to identify current clinical practice guidelines worldwide, appraise their methodological quality, and discuss variability across guidelines for the diagnosis and management of bronchiolitis.

METHODS

A systematic literature review of electronic databases EMBASE, Global Health, and Medline was performed. Manual searches of the gray literature, national pediatric society websites, and guideline-focused databases were performed, and select international experts were contacted to identify additional guidelines. The Appraisal of Guidelines for Research and Evaluation assessment tool was used by 2 independent reviewers to appraise each guideline.

RESULTS

Thirty-two clinical practice guidelines met the selection criteria. Quality assessment revealed significant shortcomings in a number of guidelines, including lack of systematic processes in formulating guidelines, failure to state conflicts of interest, and lack of consultation with families of affected children. There was widespread agreement about a number of aspects, such as avoidance of the use of unnecessary diagnostic tests, risk factors for severe disease, indicators for hospital admission, discharge criteria, and nosocomial infection control. However, there was variability, even within areas of consensus, over specific recommendations, such as variable thresholds for oxygen therapy. Guidelines showed significant variability in recommendations for the pharmacological management of bronchiolitis, with conflicting recommendations over whether use of nebulized epinephrine, hypertonic saline, or bronchodilators should be routinely trialled.

CONCLUSIONS

Future guidelines should aim to be compliant with international standards for clinical guidelines to improve their quality and clarity and to promote their adoption into practice. Variable recommendations between guidelines may reflect the evolving evidence base for bronchiolitis management, and platforms should be created to understand this variability and promote evidence-based recommendations.

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.

A comparison between high-flow nasal cannula and noninvasive ventilation in the management of infants and young children with acute bronchiolitis in the PICU

BACKGROUND

Different modalities of noninvasive respiratory support have been recommended for the management of acute bronchiolitis in the pediatric intensive care unit (PICU). High-flow nasal cannula (HFNC) is among the new modalities that have been widely used in the last decade.

METHODS

This is a retrospective study involving infants and young children between the ages of 1 month and 2 years during the respiratory season of 2016-2017 (October-May). We compared the failure rate of HFNC with the failure rates of bi-level positive airway pressure (BiPAP) vs continuous positive airway pressure (CPAP) in the management of acute bronchiolitis in the PICU. Failure was defined as a change to another respiratory support modality or endotracheal intubation and mechanical ventilation.

RESULTS

One hundred thirty-seven patients met the inclusion criteria, of which 77 patients needed HFNC, 10 needed CPAP, and 50 were on BiPAP. Among baseline characteristics, there were significant variations in age among the three groups. HFNC had a higher failure rate compared with the other two noninvasive ventilation modalities (50.6% for HFNC [n = 39 out of 77] vs 0% for CPAP [n = 0 out of 10] vs 8% for BiPAP [n = 4 out of 50], P < .01). Among the 39 patients who failed HFNC, 90% were successfully shifted to BiPAP and weaned off later, whereas the other 4 were intubated and required mechanical ventilation. However, all four patients who failed BiPAP were intubated and mechanically ventilated. No respiratory complications or mortalities were reported in the three groups. No differences were observed among the three groups in terms of the lengths of PICU or hospital stays.

CONCLUSIONS

We observed a higher failure rate of HFNC compared with BiPAP or CPAP in the management of infants and children with acute bronchiolitis in the PICU. Further prospective randomized trials are recommended to confirm this finding.

Integrating Duodenal Sampling in a Human Mass Balance Study to Quantify the Elimination Pathways of JNJ-53718678, a Respiratory Syncytial Virus Fusion Protein Inhibitor

INTRODUCTION

The study objective was to characterize the excretion and metabolic profile of the respiratory syncytial virus fusion protein inhibitor, JNJ-53718678. Prior animal and in vitro studies suggested three main elimination pathways: N-glucuronidation to M8; CYP(3A4) metabolism leading to circulating metabolites M5, M12, M19 and M37; and JNJ-53718678 biliary excretion. To gain insight into the relative contribution of JNJ-53718678 and M8 biliary excretion, duodenal fluid sampling was incorporated into this mass balance study.

METHODS

A single oral dose of 500 mg ¹⁴C-JNJ-53718678 was administered to six healthy male subjects. Four hours after study drug intake, gallbladder contraction was stimulated and duodenal fluid samples were collected. JNJ-53718678, its key circulating metabolites and total radioactivity (TR) were quantified in plasma, feces, urine and duodenal fluid. Safety was monitored throughout.

RESULTS

JNJ-53718678 and M12 represented 47.4% and 17.8%, respectively, of TR area under the curve (AUC)_∞ in plasma. M37 (9.6%), M19 (5.2%), M5 (4.3%) and M8 (1.4%) were minor metabolites; 70.6% of TR was recovered in feces and 19.9% in urine. Duodenal fluid concentrations (% of TR) were highest for JNJ-53718678 (11.6%) followed by M8 (10.4%), M5 (5.9%) and M12 (1.1%). In feces, 10-16% of TR was JNJ-53718678, 5-8% M5, < 1% M12 and < 1% M8. N-glucuronidation to M8 and direct biliary excretion of JNJ-53718678 represented 7% and 8% of drug clearance, respectively. JNJ-53718678 was safe and well tolerated.

CONCLUSIONS

JNJ-53718678 is primarily eliminated through CYP3A4-mediated metabolism. By integrating duodenal sampling, N-glucuronidation was confirmed as another metabolic pathway despite the low amount of M8 excreted in urine and feces.

TRIAL REGISTRATION

Eudract no. 2016-002664-14.

Extended use of the modified Berlin Definition based on age-related subgroup analysis in pediatric ARDS

Background

Pediatric acute respiratory distress syndrome (pARDS) is a rare but very severe condition. Management of the condition remains a major challenge for pediatric intensive care specialists.

Objective

To perform a descriptive assessment of pARDS based on the modified Berlin Definition by using the SpO₂/FiO₂ ratio in order to establish an extended patient registry divided into age-related subgroups.

Methods

The data of all children on mechanical ventilation for respiratory failure admitted between 2005 and 2012 were reviewed retrospectively for this study. The age of patients ranged from newborns >37 weeks, up to children <18 years. Inclusion criteria were based on the modified Berlin Definition of pARDS. The following data were collected: demographic data, primary diagnosis, ventilation settings, and use of supportive treatment, in addition to mechanical ventilation (inhaled nitric oxide, surfactant, corticosteroids, prone positioning, and extracorporeal membrane oxygenation).

Results

In all, 93 children where included: 35% were newborns, 29% infants, 24% toddlers, and 12% school children; 66% were male and 34% were female patients. The most common primary diagnosis was viral pneumonia (21%) and 55% of the children were diagnosed with severe ARDS. The median duration of stay on the pediatric intensive care unit was 16 days (10/27). In total, 66 children (71%) had direct lung injury and 18 (19%) had indirect lung injury. More than 80% of all children needed more than one supportive care therapy. The overall survival rate was 77%.

Conclusion

This study is a valuable report about pediatric patients with ARDS and allows for an important extension of the application of the modified Berlin Definition in all age groups.

Modified Tal Score: Validated score for prediction of bronchiolitis severity

OBJECTIVE

To further validate the use of the Modified Tal Score (MTS), a clinical tool for assessing bronchiolitis severity, by physicians with varying experience and training levels, and to determine the ability of the MTS to predict bronchiolitis severity.

METHODS

This prospective cohort study included infants of <12 months of age who were diagnosed with bronchiolitis and assessed via MTS. We calculated the intra-class correlation coefficient (ICC) among four groups of raters: group 1, board-certified pediatric pulmonologists; group 2, board-certified pediatricians; group 3, senior pediatric residents; and group 4, junior pediatric residents. Clinical outcomes were determined as length of oxygen support and length of stay (LOS). We assessed MTS's prediction of these outcomes. Relative risk (RR) for clinical severity was calculated via a Generalized Linear Model.

RESULTS

Twenty-four physicians recorded a total of 600 scores for 50 infants (average age 5 ± 3 months; 56% male). The ICC values with group 1 as a reference were 0.92, 0.87, and 0.83, for groups 2, 3, and 4, respectively (P < 0.001). RR for oxygen support required was; 1.33 (CI 1.12-1.57), 1.26 (1.1-1.46), 1.26 (1.06-1.5), and 1.21 (0.93-1.58) for groups 1, 2, 3, and 4, respectively. RR for LOS was; 1.15 (CI 0.97-1.37), 1.19 (1.03-1.38), 1.18 (1.0-1.39), and 1.18 (0.93-1.51) for groups 1, 2, 3, and 4, respectively.

CONCLUSION

The MTS is a simple and valid scoring system for evaluating infants with acute bronchiolitis, among different physician groups. The first score upon admission is a fair predictor of oxygen requirement at 48 h, and LOS at 72 h.

Update in Pediatric Hospital Medicine

Pediatric Hospital Medicine has significantly developed as a field over the past two decades. With the goal of improving care for hospitalized children, much of the research in this field has focused on reducing unnecessary interventions, optimizing necessary treatments, and reducing variability for common inpatient conditions. While this is far from an exhaustive chapter on the vast diversity and advances in this field, it focuses on the updates for some of the top diagnoses in hospital medicine and the major trends in the field. Updated management of acute viral bronchiolitis, urinary tract infections, neonatal infections, brief resolved unexplained events (formerly, apparent life-threatening events), and osteomyelitis are highlighted with emphasis on major management changes. In addition, and distinct to pediatric hospital medicine, the topics of overuse and high value care are discussed as they have gained momentum in influencing the way hospitalists think and practice.

Therapeutic efficacy of a respiratory syncytial virus fusion inhibitor

Respiratory syncytial virus is a major cause of acute lower respiratory tract infection in young children, immunocompromised adults, and the elderly. Intervention with small-molecule antivirals specific for respiratory syncytial virus presents an important therapeutic opportunity, but no such compounds are approved today. Here we report the structure of JNJ-53718678 bound to respiratory syncytial virus fusion (F) protein in its prefusion conformation, and we show that the potent nanomolar activity of JNJ-53718678, as well as the preliminary structure–activity relationship and the pharmaceutical optimization strategy of the series, are consistent with the binding mode of JNJ-53718678 and other respiratory syncytial virus fusion inhibitors. Oral treatment of neonatal lambs with JNJ-53718678, or with an equally active close analog, efficiently inhibits established acute lower respiratory tract infection in the animals, even when treatment is delayed until external signs of respiratory syncytial virus illness have become visible. Together, these data suggest that JNJ-53718678 is a promising candidate for further development as a potential therapeutic in patients at risk to develop respiratory syncytial virus acute lower respiratory tract infection.

Respiratory syncytial virus causes lung infections in children, immunocompromised adults, and in the elderly. Here the authors show that a chemical inhibitor to a viral fusion protein is effective in reducing viral titre and ameliorating infection in rodents and neonatal lambs.

Systematic Review and Meta-Analysis of the Efficacy and Safety of Combined Epinephrine and Corticosteroid Therapy for Acute Bronchiolitis in Infants

Objective: To evaluate the effectiveness of combined epinephrine and corticosteroid therapy for acute bronchiolitis in infants.

Methods: Four electronic databases (MEDLINE, EMBASE, CINAHL, and CENTRAL) were searched from their inception to February 28, 2017 for studies involving infants aged less than 24 months with bronchiolitis which assessed the use of epinephrine and corticosteroid combination therapy. The methodological quality of the included studies was assessed using the Cochrane Collaboration's Risk of Bias Tool. A random-effects meta-analysis was used to pool the effect estimates. The primary outcomes were hospital admission rate and length of hospital stay.

Results: Of 1,489 citations identified, 5 randomized controlled trials involving 1,157 patients were included. All studies were of high quality and low risk of bias. Results of the meta-analysis showed no significant differences in the primary outcomes. Hospitalization rate was reduced by combinatorial therapy of epinephrine and corticosteroid in only one out of five studies, whereas pooled data indicated no benefit over epinephrine plus placebo. Clinical severity scores were significantly improved in all five RCTs when assessed individually, but no benefit was observed compared to epinephrine monotherapy when the data were pooled together. Pooled data showed that combination therapy was more effective at improving oxygen saturation level (mean difference: −0.70; 95% confidence interval: −1.17 to −0.22, p = 0.004). There was no difference in the risk of serious adverse events in infants treated with the combined epinephrine and corticosteroid therapy.

Conclusions: Combination treatment of epinephrine and dexamethasone was ineffective in reducing hospital admission and length of stay among infants with bronchiolitis.

Etiology, Seasonality, and Clinical Features of Viral Respiratory Tract Infections in Children Hospitalized With Acute Bronchiolitis: A Single-Center Study

The purpose of this study was to evaluate the viral frequency, seasonality, and clinical and demographic features of patients hospitalized with acute bronchiolitis. A cross-sectional, descriptive study was performed in 316 infants younger than 2 years of age who were hospitalized for acute viral bronchiolitis. Respiratory tract infection agents were investigated with polymerase chain reaction (PCR). A total of 316 infants were included in this study. Of the 316 infants, at least one respiratory tract pathogen was detected in 75% (237/316). Respiratory syncytial virus (RSV) was the most common virus identified in 127 infants (40.1%) followed by rhinovirus (n = 78, 24.6%). In this study, where viral agents were determined via PCR in patients who were followed-up due to the diagnosis of acute bronchiolitis, RSV was detected as the most common agent, as in other studies. In almost half of the RSV-positive patients, RSV was accompanied by a second or third agent.

IV Magnesium Sulfate for Bronchiolitis: A Randomized Trial

BACKGROUND

The goal of this study was to determine if IV magnesium, useful for severe pediatric asthma, reduces time to medical readiness for discharge in patients with bronchiolitis when added to supportive care.

METHODS

We compared a single dose of 100 mg/kg of IV magnesium sulfate vs placebo for acute bronchiolitis. Patients received bronchodilator therapy, nebulized hypertonic saline, and 5 days of dexamethasone if there was eczema and/or a family history of asthma. Time to medical readiness for discharge was the primary efficacy outcome. Bronchiolitis severity scores and need for infirmary or hospital admission and for clinic revisits within 2 weeks were secondary outcomes. Cardiorespiratory instability onset was the safety outcome.

RESULTS

A total of 162 previously healthy infants diagnosed with bronchiolitis aged 22 days to 17.6 months (median, 3.7 months) were enrolled. Approximately one-half of patients had eczema and/or a family history of asthma; 86.4% had positive findings on nasopharyngeal virus swabs. Geometric mean time until medical readiness for discharge was 24.1 h (95% CI, 20.0-29.1) for the 78 magnesium-treated patients and 25.3 h (95% CI, 20.3-31.5) for the 82 patients receiving placebo (ratio, 0.95 [95% CI, 0.52-1.80]; P = .91). Mean bronchiolitis severity scores over time were similar for the two groups. The frequency of clinic visits in the subsequent 2 weeks (33.8% and 27.2%, respectively) was also similar. Fifteen magnesium recipients (19.5%) vs five placebo recipients (6.2%) were readmitted to the infirmary or hospital within 2 weeks (P = .016). No acute cardiorespiratory side effects were reported.

CONCLUSIONS

IV magnesium did not provide benefit for patients with acute bronchiolitis and may be harmful.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT02145520; URL: www.clinicaltrials.gov.

Viral aetiology of bronchiolitis in hospitalised children in Qatar

Background

Bronchiolitis is considered one of the earliest and most common causes of hospitalisation in young children. Development of molecular technologies allowed a better understanding of bronchiolitis aetiology. Results from cohort studies evaluating the association between single, multiple viral infections and clinical outcomes are conflicting. Data on viral bronchiolitis in children were found to be limited in Qatar. This study aimed to determine frequency and seasonal trends of viral pathogens causing acute bronchiolitis, and to explore association between viral pathogens, disease severity and length of stay (LOS).

Methods

This is a retrospective descriptive study, including children admitted in 2010 and 2011 with acute bronchiolitis. Presenting history, physical examination and respiratory viral co-infections as detected by molecular assays were analysed.

Results

At least one virus was detected in 315/369 (85.4%) of included children with single and multiple viruses in 67 and 33% of cases respectively. Respiratory syncytial virus (RSV) was the most detected virus, accounting for 51.2% followed by rhinovirus (RV) in 25.5% of cases. Fall and summer admissions were associated with longer LOS. On multivariate logistic regression analysis, retraction (OR 3.96; 95% CI 1.64,9.59) and age group 1–3 months (OR 3.09; 95% CI 1.06,9.05) were associated with longer LOS. Crepitation (OR 9.15; 95% CI 1.58,53.13), retraction (OR 4.10; 95% CI 1.05,16.12) and respiratory rate (OR 1.46; 95% CI 1.28,1.66) were associated with moderate to severe bronchiolitis. Identifying the viral agent did not influence disease severity or LOS.

Conclusion

Clinical presentation is of more relevance to LOS and disease severity than the detected viruses. Future studies should investigate the interplay between climate characteristics, population’s factors and the most detectable circulating viruses.

Electronic supplementary material

The online version of this article (doi:10.1186/s12879-017-2225-z) contains supplementary material, which is available to authorized users.

Antiviral activity of polysaccharide extract from Laminaria japonica against respiratory syncytial virus

This study was designed to investigate the inhibition activity of polysaccharide extract from Laminaria japonica against RSV. The polysaccharide from Laminaria japonica was isolated by ethanol precipitation. HEK293 cells were infected with RVS, and the antiviral activity of polysaccharide extract against RSV in host cells was tested. By using ELISA and western blot assay, the expression level of IFN-α and IRF3 and their functional roles in polysaccharide-mediated antiviral activity against RSV were investigated. The polysaccharide extract from Laminaria japonica had low toxicity to HEK293 cell. The TC50 to HEK293 cells was up to 1.76mg/mL. Furthermore, the EC50 of polysaccharide extract to RSV was 5.27μg/mL, and TI was 334. The polysaccharide extract improved IRF-3 expression which promoted the level of IFN-α.

IN CONCLUSION

Polysaccharide extract from Laminaria japonica elicits antiviral activity against RSV by up-regulation of IRF3 signaling-mediated IFN-α production.

A systematic review of the psychometric properties of bronchiolitis assessment tools

AIM

The aim of this study was to assess the psychometric properties of tools developed for the purpose of assessing infants with bronchiolitis.

BACKGROUND

Bronchiolitis is the leading cause of hospitalization in infants under the age of 1 year. Several bronchiolitis assessment tools have been developed primarily for use in randomized control trials of medical treatments for infants with bronchiolitis, however, the reliability and validity of many of these tools is not well reported.

DESIGN

Systematic review.

DATA SOURCES

CINAHL, MEDLINE, EMBASE and PubMed electronic databases were searched between January 1960-December 2015 using the key words 'bronchiolitis' and 'assessment' or 'screen' or 'tool' or 'scale' or 'score'.

REVIEW METHODS

A systematic review of the psychometric properties of bronchiolitis assessment tools was undertaken using the COSMIN checklist.

RESULTS

Fourteen studies meeting the inclusion criteria were reviewed and the methodological quality of the studies and reported psychometric properties of 11 instruments were assessed. Overall, the reliability and validity of bronchiolitis assessment tools was poorly established. Although several studies reported that their tools had good inter-rater reliability, the methodological quality of these studies was generally poor. Only one study underwent psychometric testing that was assessed as being of excellent quality. The Respiratory Distress Assessment Index was deemed to have undergone the most rigorous psychometric testing but had poor to moderate construct validity and considerable test-retest error.

CONCLUSION

Current bronchiolitis assessment tools lack clearly established reliability and validity and may not be sensitive to clinically meaningful outcomes for patients.

A regional cohort study of the treatment of critically ill children with bronchiolitis

OBJECTIVE

To describe the treatment practices in critically ill children with RSV bronchiolitis across four regional PICUs in the northeastern United States, and to determine the factors associated with increased ICU length of stay in this population.

METHODS

We conducted a retrospective cohort study of children who were admitted with RSV bronchiolitis between July 2009 and July 2011 to the PICUs of Connecticut Children's Medical Center, Yale-New Haven Children's Hospital, Maria Fareri Children's Hospital, and Baystate Children's Hospital. Data were collected regarding clinical characteristics and intensive care course among these hospitals.

RESULTS

During the study period, 323 children were admitted to one of the four ICUs with RSV bronchiolitis. Despite similar mortality risk scores among ICUs, there was considerable variation in the use of therapies, particularly intubation and mechanical ventilation, in which there was greater than a 3.5-fold increased risk of intubation between sites with the highest and lowest frequency of intubation (odds ratio: 3.8; 95% confidence interval: 2.2-6.4). Albuterol was the most commonly used respiratory treatment, followed by chest physiotherapy, high-flow nasal cannula, and hypertonic saline. Longer stays in the ICU were associated with more frequent use of therapies, specifically invasive mechanical ventilation, inhaled corticosteroids, intrapulmonary percussive ventilation, and chest physiotherapy.

CONCLUSIONS

Even within a close geographic region, there is significant variation in the treatment provided to critically ill children with RSV bronchiolitis. None of these treatments were associated with shorter durations of hospitalization in this population and some, such as mechanical ventilation, were associated with longer ICU lengths of stay.

Hypertonic Saline for the Treatment of Bronchiolitis in Infants and Young Children: A Critical Review of the Literature

Bronchiolitis, an infection of the lower respiratory tract, is the leading cause of infant and child hospitalization in the United States. Therapeutic options for management of bronchiolitis are limited. Hypertonic saline inhalation therapy has been studied in numerous clinical trials with mixed results. In 2014, the American Academy of Pediatrics (AAP) published updated guidelines on the diagnosis and management of bronchiolitis, which include new recommendations on the use of hypertonic saline. We reviewed all published clinical trials mentioned in the 2014 AAP guidelines, as well as additional trials published since the guidelines, and critically evaluated each trial to determine efficacy, safety, and expectations of hypertonic saline inhalation therapy. A total of 2682 infants were studied over the course of 22 clinical trials. Nine trials were carried out in the outpatient/clinic/emergency department and 13 in the inpatient setting. We agree with the AAP guidelines regarding the recommendation to use nebulized hypertonic saline for infants hospitalized with bronchiolitis, with the expectation of reducing bronchiolitis scores and length of stay when it is expected to last more than 72 hours. However, we also believe there might be an advantage for hypertonic saline in reducing admission rates from the emergency department, based on close examination of the results of recent trials. This review also highlights important gaps in the available literature that need to be addressed in order to define the role of inhaled hypertonic saline therapy.

Genetic association of TLR4 Asp299Gly, TLR4 Thr399Ile, and CD14 C-159T polymorphisms with the risk of severe RSV infection: a meta-analysis

Respiratory syncytial virus (RSV) is the most frequent cause of hospitalization in infants worldwide. It is recognized by Toll‐like receptor 4 (TLR 4) and cluster of differentiation 14 (CD14) in the innate immune response. Previous case–control studies reported the influence of TLR4 Asp299Gly, TLR4 Thr399Ile, and CD14 C‐159T polymorphisms on the risk of severe RSV infection. However, a decisive conclusion has not been achieved. Therefore, we performed this meta‐analysis to examine the association between these three polymorphisms and the development of RSV bronchiolitis. A systematic literature search was performed using the PubMed, EMbase, Google Scholar Search, China National Knowledge Infrastructure, China Biological Medicine, and Wanfang Databases. The data were extracted and pooled odds ratios with 95% confidence intervals were calculated under six genetic models. A total of six studies with 1009 cases and 1348 controls, three studies with 473 cases and 481 controls, or four studies with 325 cases and 650 controls relating to each of the three polymorphisms were included in this meta‐analysis. The analyzed data indicated that all of these polymorphisms were not associated with the risk of severe RSV infection. This is the first meta‐analysis to investigate the relationship of TLR4 Asp299Gly, TLR4 Thr399Ile, and CD14 C‐159T polymorphisms with the risk of severe RSV infection. Although the results of this retrospective analysis indicated a lack of the association, more extensive multicentric studies with large sample sizes are necessary to provide a more reliable estimation of the association between these three polymorphisms and RSV bronchiolitis susceptibility.

Chest physiotherapy for acute bronchiolitis in paediatric patients between 0 and 24 months old

BACKGROUND

This Cochrane review was first published in 2005 and updated in 2007, 2012 and now 2015. Acute bronchiolitis is the leading cause of medical emergencies during winter in children younger than two years of age. Chest physiotherapy is sometimes used to assist infants in the clearance of secretions in order to decrease ventilatory effort.

OBJECTIVES

To determine the efficacy of chest physiotherapy in infants aged less than 24 months old with acute bronchiolitis. A secondary objective was to determine the efficacy of different techniques of chest physiotherapy (for example, vibration and percussion and passive forced exhalation).

SEARCH METHODS

We searched CENTRAL (2015, Issue 9) (accessed 8 July 2015), MEDLINE (1966 to July 2015), MEDLINE in-process and other non-indexed citations (July 2015), EMBASE (1990 to July 2015), CINAHL (1982 to July 2015), LILACS (1985 to July 2015), Web of Science (1985 to July 2015) and Pedro (1929 to July 2015).

SELECTION CRITERIA

Randomised controlled trials (RCTs) in which chest physiotherapy was compared against no intervention or against another type of physiotherapy in bronchiolitis patients younger than 24 months of age.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data. Primary outcomes were change in the severity status of bronchiolitis and time to recovery. Secondary outcomes were respiratory parameters, duration of oxygen supplementation, length of hospital stay, use of bronchodilators and steroids, adverse events and parents' impression of physiotherapy benefit. No pooling of data was possible.

MAIN RESULTS

We included 12 RCTs (1249 participants), three more than the previous Cochrane review, comparing physiotherapy with no intervention. Five trials (246 participants) evaluated conventional techniques (vibration and percussion plus postural drainage), and seven trials (1003 participants) evaluated passive flow-oriented expiratory techniques: slow passive expiratory techniques in four trials, and forced passive expiratory techniques in three trials.Conventional techniques failed to show a benefit in the primary outcome of change in severity status of bronchiolitis measured by means of clinical scores (five trials, 241 participants analysed). Safety of conventional techniques has been studied only anecdotally, with one case of atelectasis, the collapse or closure of the lung resulting in reduced or absent gas exchange, reported in the control arm of one trial.Slow passive expiratory techniques failed to show a benefit in the primary outcomes of severity status of bronchiolitis and in time to recovery (low quality of evidence). Three trials analysing 286 participants measured severity of bronchiolitis through clinical scores, with no significant differences between groups in any of these trials, conducted in patients with moderate and severe disease. Only one trial observed a transient significant small improvement in the Wang clinical score immediately after the intervention in patients with moderate severity of disease. There is very low quality evidence that slow passive expiratory techniques seem to be safe, as two studies (256 participants) reported that no adverse effects were observed.Forced passive expiratory techniques failed to show an effect on severity of bronchiolitis in terms of time to recovery (two trials, 509 participants) and time to clinical stability (one trial, 99 participants analysed). This evidence is of high quality and corresponds to patients with severe bronchiolitis. Furthermore, there is also high quality evidence that these techniques are related to an increased risk of transient respiratory destabilisation (risk ratio (RR) 10.2, 95% confidence interval (CI) 1.3 to 78.8, one trial) and vomiting during the procedure (RR 5.4, 95% CI 1.6 to 18.4, one trial). Results are inconclusive for bradycardia with desaturation (RR 1.0, 95% CI 0.2 to 5.0, one trial) and bradycardia without desaturation (RR 3.6, 95% CI 0.7 to 16.9, one trial), due to the limited precision of estimators. However, in mild to moderate bronchiolitis patients, forced expiration combined with conventional techniques produced an immediate relief of disease severity (one trial, 13 participants).

AUTHORS' CONCLUSIONS

None of the chest physiotherapy techniques analysed in this review (conventional, slow passive expiratory techniques or forced expiratory techniques) have demonstrated a reduction in the severity of disease. For these reasons, these techniques cannot be used as standard clinical practice for hospitalised patients with severe bronchiolitis. There is high quality evidence that forced expiratory techniques in severe patients do not improve their health status and can lead to severe adverse events. Slow passive expiratory techniques provide an immediate and transient relief in moderate patients without impact on duration. Future studies should test the potential effect of slow passive expiratory techniques in mild to moderate non-hospitalised patients and patients who are respiratory syncytial virus (RSV) positive. Also, they could explore the combination of chest physiotherapy with salbutamol or hypertonic saline.

Nebulized Hypertonic Saline for Acute Bronchiolitis: A Systematic Review

BACKGROUND AND OBJECTIVE

The mainstay of treatment for acute bronchiolitis remains supportive care. The objective of this study was to assess the efficacy and safety of nebulized hypertonic saline (HS) in infants with acute bronchiolitis.

METHODS

Data sources included PubMed and the Virtual Health Library of the Latin American and Caribbean Center on Health Sciences Information up to May 2015. Studies selected were randomized or quasi-randomized controlled trials comparing nebulized HS with 0.9% saline or standard treatment.

RESULTS

We included 24 trials involving 3209 patients, 1706 of whom received HS. Hospitalized patients treated with nebulized HS had a significantly shorter length of stay compared with those receiving 0.9% saline or standard care (15 trials involving 1956 patients; mean difference [MD] -0.45 days, 95% confidence interval [CI] -0.82 to -0.08). The HS group also had a significantly lower posttreatment clinical score in the first 3 days of admission (5 trials involving 404 inpatients; day 1: MD -0.99, 95% CI -1.48 to -0.50; day 2: MD -1.45, 95% CI -2.06 to -0.85; day 3: MD -1.44, 95% CI -1.78 to -1.11). Nebulized HS reduced the risk of hospitalization by 20% compared with 0.9% saline among outpatients (7 trials involving 951 patients; risk ratio 0.80, 95% CI 0.67-0.96). No significant adverse events related to HS inhalation were reported. The quality of evidence is moderate due to inconsistency in results between trials and study limitations (risk of bias).

CONCLUSIONS

Nebulized HS is a safe and potentially effective treatment of infants with acute bronchiolitis.

β2-Adrenergic receptor promoter haplotype influences the severity of acute viral respiratory tract infection during infancy: a prospective cohort study

BACKGROUND

Despite the significant interest in β2-Adrenergic receptor (ADRB2) polymorphisms related to asthma, whether ADRB2 genetic variants are similarly associated with acute respiratory tract infections have not been studied. We hypothesized that genetic variants in ADRB2 associated with a response to asthma therapy during an asthma exacerbation were also associated with severity of acute respiratory tract infections.

METHODS

To test this hypothesis, we genotyped 5 common polymorphisms in the promoter region and coding block of the ADRB2 gene (loci -2387, -2274, -1343, +46, and +79) from 374 Caucasian and African American term infants who were enrolled at the time of acute respiratory illness over four respiratory viral seasons. Severity of respiratory tract infections was measured using a bronchiolitis severity score (BSS; range = 0-12, clinically significant difference = 0.5) with a higher score indicating more severe disease. We assigned the promoter, coding and combined promoter and coding haplotypes to the unphased genotype data. The associations between each of these five single-nucleotide polymorphisms (SNPs) as well as the haplotypes and infant BSS were analyzed using nonparametric univariate analysis and multivariable proportional odds model separately in Caucasians and African Americans.

RESULTS

There was no significant association between infant BSS and each of the SNPs in both Caucasians and African Americans. However, promoter haplotype CCA was associated with a decreased BSS in African Americans in a dose dependent manner. The median (interquartile range) BSS of infants with no copies of the CCA haplotype, one copy, and two copies of the CCA haplotype were 5.5 (2.0, 8.0), 4.0 (1.0, 7.5), and 3.0 (1.0, 4.0), respectively. This dose dependent relationship persisted after adjusting for infant age, gender, daycare exposure, secondhand smoke exposure, prior history of breastfeeding, siblings at home, and enrollment season (adjusted odds ratio: 0.59, 95% confidence interval: 0.36, 0.98). There was no similar protective relationship of haplotype CCA on severity of respiratory tract infections identified in Caucasians.

CONCLUSIONS

ADRB2 genotype may be predictive of severity of acute respiratory tract infections in African Americans, and potentially identify a subset of infants who may respond to beta-agonist therapy.

Nebulised hypertonic saline (3%) among children with mild to moderately severe bronchiolitis--a double blind randomized controlled trial

BACKGROUND

To Assess the efficacy of nebulised hypertonic saline (HS) (3%) among children with mild to moderately severe bronchiolitis.

METHODS

Infants aged 6 weeks to 24 months, with a first episode of wheezing and Clinical Severity scores (Arch Dis Child 67:289-93, 1992) between 1 and 8, were enrolled over 4 months duration. Those with severe disease, co-morbidities, prior wheezing, recent bronchodilator and steroid use were excluded. Patients were randomized in a double-blind fashion, to receive two doses of nebulized 3% HS (Group 1) or 0.9% normal saline (Group 2) with 1.5 mg of L-Epineprine, delivered 30 min apart. Parents were contacted at 24 h and 7 days. The principal outcome measure was the mean change in clinical severity score at the end of 2 h of observation.

RESULTS

A total of 100 infants (mean age 9.6 months, range 2-23 months; 61 % males) were enrolled. Patients in both groups had mild to moderately severe disease at presentation. On an intention-to-treat basis, the infants in the HS group had a significant reduction (3.57 ± 1.41) in the mean clinical severity score compared to those in the NS group (2.26 ± 1.15); [p < 0.001; CI: 0.78-1.82]. More children in the HS group (n = 35/50; 70.0%) were eligible for ER/OPD discharge at the end of 2 h than those in the NS group (n = 15/50; 30%; p < 0.001), and less likely to need a hospital re-visit (n = 5/50; 10.0%) in the next 24 h as compared to the NS group (n = 15/50, 30.0%; p < 0.001). The treatment was well tolerated, with no adverse effects.

CONCLUSIONS

Nebulized 3% HS is effective, safe and superior to normal saline for outpatient management of infants with mild to moderately severe viral bronchiolitis in improving Clinical Severity Scores, facilitating early Out-Patient Department discharge and preventing hospital re-visits and admissions in the 24 h of presentation.

TRIAL REGISTRATION

Clinicaltrials.gov NCTID012766821. Registered on January 12, 2011.

Non-invasive ventilation is useful in paediatric intensive care units if children are appropriately selected and carefully monitored

Non-invasive ventilation (NIV) is commonly used in paediatric intensive care units (PICUs) for respiratory failure. This review aims to improve paediatricians' understanding of NIV, by specifying technical or practical considerations, giving advice about selecting patients and presenting pertinent published data about NIV in different circumstances.

CONCLUSION

NIV is useful in PICUs if children are appropriately selected and carefully monitored. Technological advances and future clinical research will improve its use and success rate in PICU.

In silico structure-based design and synthesis of novel anti-RSV compounds

Respiratory syncytial virus (RSV) is the major cause for respiratory tract disease in infants and young children. Currently, no licensed vaccine or a selective antiviral drug against RSV infections are available. Here, we describe a structure-based drug design approach that led to the synthesis of a novel series of zinc-ejecting compounds active against RSV replication. 30 compounds, sharing a common dithiocarbamate moiety, were designed and prepared to target the zinc finger motif of the M2-1 protein. A library of ∼ 12,000 small fragments was docked to explore the area surrounding the zinc ion. Among these, seven ligands were selected and used for the preparation of the new derivatives. The results reported here may help the development of a lead compound for the treatment of RSV infections.

Variability in inpatient management of children hospitalized with bronchiolitis

OBJECTIVE

To determine the variability between hospitals in diagnostic testing and management interventions for children with bronchiolitis admitted to inpatient wards and identify its association with patient characteristics.

METHODS

A prospective, multicenter (16 hospitals), multiyear (2007-2010) observational study of children (age <2 years) hospitalized with bronchiolitis. Outcomes included variability in diagnostic testing (complete blood count, chest radiographs) and medications or interventions (bronchodilator, systemic corticosteroid, antibiotic, IV placement) by hospital. A modified Respiratory Distress Severity Score was utilized to assess severity of illness. For all outcomes, intraclass correlation coefficient (ICC) was calculated from a model to estimate the random effects of hospital without added covariates and compared to ICCs from a second model that adjusted for demographic and clinical patient characteristics. A second unadjusted and adjusted model was created for age ≥ 2 months.

RESULTS

Of 2207 subjects, 1715 were identified as admitted to inpatient wards. We observed wide variations in the proportion of patients who received diagnostic testing (complete blood count 21-75%, chest radiograph 36-85%) and medications/interventions (bronchodilators 19-91%, systemic corticosteroids 8-44%, antibiotics 17-43%, IV placement 38-93%). Adjusting for demographic and clinical patient characteristics did not materially affect the proportion of variability attributable to hospitals (differences in ICCs with and without model adjustment <4%).

CONCLUSIONS

Wide variations in diagnostic test utilization and management interventions seen among children with bronchiolitis treated on the inpatient wards at 16 US hospitals were not attributable to demographic or clinical patient characteristics. These results further support efforts to standardize care for bronchiolitis through active quality improvement strategies.

Bronchiolitis: Recommendations for diagnosis, monitoring and management of children one to 24 months of age

Bronchiolitis is the most common reason for admission to hospital in the first year of life. There is tremendous variation in the clinical management of this condition across Canada and around the world, including significant use of unnecessary tests and ineffective therapies. This statement pertains to generally healthy children ≤2 years of age with bronchiolitis. The diagnosis of bronchiolitis is based primarily on the history of illness and physical examination findings. Laboratory investigations are generally unhelpful. Bronchiolitis is a self-limiting disease, usually managed with supportive care at home. Groups at high risk for severe disease are described and guidelines for admission to hospital are presented. Evidence for the efficacy of various therapies is discussed and recommendations are made for management. Monitoring requirements and discharge readiness from hospital are also discussed.