Infant Bronchiolitis Endotypes and the Risk of Developing Childhood Asthma: Lessons From Cohort Studies.

Severe bronchiolitis (i.e., bronchiolitis requiring hospitalization) during infancy is a heterogeneous condition associated with a high risk of developing childhood asthma. Yet, the exact mechanisms underlying the bronchiolitis-asthma link remain uncertain. Birth cohort studies have reported this association at the population level, including only small groups of patients with a history of bronchiolitis, and have attempted to identify the underlying biological mechanisms. Although this evidence has provided valuable insights, there are still unanswered questions regarding severe bronchiolitis-asthma pathogenesis. Recently, a few bronchiolitis cohort studies have attempted to answer these questions by applying unbiased analytical approaches to biological data. These cohort studies have identified novel bronchiolitis subtypes (i.e., endotypes) at high risk for asthma development, representing essential and enlightening evidence. For example, one distinct severe respiratory syncytial virus (RSV) bronchiolitis endotype is characterized by the presence of Moraxella catarrhalis and Streptococcus pneumoniae, higher levels of type I/II IFN expression, and changes in carbohydrate metabolism in nasal airway samples, and is associated with a high risk for childhood asthma development. Although these findings hold significance for the design of future studies that focus on childhood asthma prevention, they require validation. However, this scoping review puts the above findings into clinical context and emphasizes the significance of future research in this area aiming to offer new bronchiolitis treatments and contribute to asthma prevention.

Association between goal nutrition and intubation in patients with bronchiolitis on noninvasive ventilation: A retrospective cohort study.

BACKGROUND: Acute bronchiolitis causes many hospitalizations in children younger than 2 years. Early enteral nutrition is associated with improved outcomes in these patients. However, often nutrition is withheld when patients require noninvasive respiratory support because of the risk of aspiration worsening respiratory failure, possibly requiring intubation. We hypothesize that achieving goal energy intake is associated with a lower intubation rate in hospitalized children with bronchiolitis who require noninvasive ventilation. METHODS: This retrospective cohort study examined the association between goal enteral nutrition (60% of dietary reference energy intake) and intubation rates. We grouped patients by severity of illness and compared intubation rates in those who met goal energy to those who did not. We use stratified analysis methods (for both level of respiratory support and feeding route) to evaluate progression to intubation. RESULTS: Of the 272 patients, 215 met goal feeds. These groups had similar demographics, but the goal-feeds group started on higher respiratory support in the pediatric intensive care unit. We found that 4.65% of the patients who met goal feeds required intubation compared with 24.6% of patients who did not meet goal feeds (P < 0.0001), even after controlling for respiratory status at admission and time of feed initiation and feeding route. CONCLUSION: We observed when adjusting for severity, feeding route, and respiratory support, achieving goal energy intake remained associated with a lower rate of intubation, without higher rates of aspiration. Confounding factors include practice variation and difference in severity of illness that objective scoring may have missed.

Chest imaging classification in Mycoplasma pneumoniae pneumonia is associated with its clinical features and outcomes.

BACKGROUND: The imaging findings of Mycoplasma pneumoniae pneumonia (MPP) vary; however, few studies have focused on the relationship of imaging classification with clinical manifestations and outcomes. OBJECTIVE: To prospectively investigate whether chest imaging classification in Mycoplasma pneumoniae pneumonia (MPP) is associated with its clinical features and outcomes. METHODS: A total of 1,401 hospitalized children with MPP were enrolled from January 2019 to December 2021. Imaging findings were categorized as bronchopneumonia and consolidation/atelectasis according to X-ray, and bronchopneumonia, consolidation/atelectasis, bronchiolitis, and mosaic pattern according to computed tomography (CT). Clinical characteristics and outcomes of patients with different imaging classifications were prospectively analyzed based on electronic medical records. RESULTS: Bronchopneumonia was the most common finding (59.6%), while consolidation/atelectasis was the most severe group. Clinical manifestations and laboratory indicators for the consolidation/atelectasis group included serious abnormalities. Further, outcomes of the patients were worse, including having longer total durations of fever and hospitalization, greater hospitalization expenses, and a higher likelihood of developing refractory MPP, necrotizing pneumonia, and bronchiolitis obliterans (BO) in this group. The incidence of bronchiolitis, a disease characterized by a high prevalence of fever, moist rales, and an atopic constitution, tended to increase after the coronavirus disease pandemic and predisposed patients to BO. A mosaic pattern occurred in allergic and young individuals, with wheezing as the main manifestation, with patients having relatively mild symptoms and good outcomes. CONCLUSION: Different imaging classifications have different clinical features and clinical outcomes; thus, formulating an imaging-based classification system is of great clinical value.

Low peripheral blood chemokine (C-C motif) ligand 5 and tumor necrosis factor α gene expression is associated with unfavorable progression of respiratory syncytial virus bronchiolitis in infants.

OBJECTIVES: We aimed to analyze whether the expression of inflammatory and antiviral genes in respiratory syncytial virus (RSV)-infected infants' peripheral blood is associated with bronchiolitis progression. METHODS: We conducted a prospective study on 117 infants between 2015 and 2023. The expression levels of nine genes were quantified by quantitative polymerase chain reaction. Infants were classified according to their clinical evolution during hospital admission: (i) non-progression (n = 74), when the RSV bronchiolitis severity remained stable or improved; (ii) unfavorable progression (n = 43), when the RSV bronchiolitis severity increased. The association analysis was performed by logistic regression, adjusted by age, gender, prematurity, and RSV bronchiolitis severity in the emergency room. RESULTS: Infants were 57.3% male, and the median age of the study population was 61 days. Thirty-five infants (30.7%) were admitted to the intensive care unit after hospital admission. Univariate logistic models showed that tumor necrosis factor (TNFα) and chemokine (C-C motif) ligand (CCL5) gene expression at baseline were inversely associated with unfavorable progression, which was confirmed by multivariate analyses: TNFα (adjusted odds ratio = 0.8 [95% confidence interval = 0.64-0.99], P-value = 0.038) and CCL5 (adjusted odds ratio = 0.76 [95% confidence interval = 0.62-0.93], P-value = 0.007). CONCLUSIONS: An inadequate immune response to RSV, characterized by reduced gene expression levels of CCL5 and TNFα in peripheral blood, was associated with an unfavorable progression of RSV bronchiolitis.

Predicting long-term neurocognitive outcome after pediatric intensive care unit admission for bronchiolitis-preliminary exploration of the potential of machine learning.

PURPOSE: For successful prevention and intervention, it is important to unravel the complex constellation of factors that affect neurocognitive functioning after pediatric intensive care unit (PICU) admission. This study aims (1) to elucidate the potential relevance of patient and PICU-related characteristics for long-term adverse neurocognitive outcome after PICU admission for bronchiolitis, and (2) to perform a preliminary exploration of the potential of machine learning as compared to linear regression to improve neurocognitive outcome prediction in a relatively small sample of children after PICU admission. METHODS: This cross-sectional observational study investigated 65 children aged 6-12 years with previous PICU admission for bronchiolitis (age ≤ 1 year). They were compared to demographically comparable healthy peers (n = 76) on neurocognitive functioning. Patient and PICU-related characteristics used for the prediction models were as follows: demographic characteristics, perinatal and disease parameters, laboratory results, and intervention characteristics, including hourly validated mechanical ventilation parameters. Neurocognitive outcome was measured by intelligence and computerized neurocognitive testing. Prediction models were developed for each of the neurocognitive outcomes using Regression Trees, k-Nearest Neighbors, and conventional linear regression analysis. RESULTS: The patient group had lower intelligence than the control group (p < .001, d = -0.59) and poorer performance in neurocognitive functions, i.e., speed and attention (p = .03, d = -0.41) and verbal memory (p < .001, d = -0.60). Lower intelligence was predicted by lower birth weight and lower socioeconomic status (R2 = 25.9%). Poorer performance on the speed and attention domain was predicted by younger age at follow-up (R2 = 53.5%). Poorer verbal memory was predicted by lower birth weight, younger age at follow-up, and greater exposure to acidotic events (R2 = 50.6%). The machine learning models did not reveal added value in terms of model performance as compared to linear regression. CONCLUSION: The findings of this study suggest that in children with previous PICU admission for bronchiolitis, (1) lower birth weight, younger age at follow-up, and lower socioeconomic status are associated with poorer neurocognitive outcome; and (2) greater exposure to acidotic events during PICU admission is associated with poorer verbal memory outcome. The findings of this study provide no evidence for the added value of machine learning models as compared to linear regression analysis in the prediction of long-term neurocognitive outcome in a relatively small sample of children. WHAT IS KNOWN: • Adverse neurocognitive outcomes are described in PICU survivors, which are known to interfere with development in other major domains of functioning, such as mental health, academic achievement, and socioeconomic success, highlighting neurocognition as an important outcome after PICU admission. • Machine learning is a rapidly growing field of artificial intelligence that is increasingly applied in health care settings, with great potential to capture the complexity of outcome prediction. WHAT IS NEW: • This study shows that lower birth weight, lower socioeconomic status, and greater exposure to acidotic events during PICU admission for bronchiolitis are associated with poorer long-term neurocognitive outcome after PICU admission. Results provide no evidence for the added value of machine learning models in a relatively small sample of children. • As bronchiolitis seldom manifests neurologically, the relation between acidotic events and neurocognitive outcome may reflect either potentially harmful effects of acidosis itself or related processes such as hypercapnia or hypoxic and/or ischemic events during PICU admission. This study further highlights the importance of structured follow-up to monitor long-term outcome of children after PICU admission.

Bronchiolitis hospital admission in infancy is associated with later preschool ventilation inhomogeneity.

BACKGROUND: Rhinovirus (RV) positive bronchiolitis episodes in infancy confer a higher risk to develop asthma in later childhood with associated lung function impairments. We aimed to investigate the association between the type of virus causing a bronchiolitis hospitalization episode and lung ventilation inhomogeneities at preschool age. METHODS: Infants hospitalized with a clinical diagnosis of moderate (ward admission) or severe (pediatric intensive care ward admission) bronchiolitis were prospectively followed-up at preschool age to assess nitrogen (N2 ) multiple breath washout (MBW). Lung clearance index (LCI), functional residual capacity (FRC), and concentration normalized phase III slope analysis (SnIII ) indices were reported from ≥2 technically acceptable trials. Differences between groups were calculated using logistic and linear regression and adjusted for confounders (sex, age at bronchiolitis admission, height at visit, maternal asthma, and doctor-diagnosed asthma, including interaction terms between the latter three). An interaction term was included in a regression model to test for an interaction between RV bronchiolitis severity and MBW parameters at preschool age. RESULTS: One hundred and thirty-nine subjects attended preschool follow-up, of which 84 out of 103 (82%) performing MBW had technically acceptable data. Children with a history of RV positive bronchiolitis (n = 39) had increased LCI (adjusted ß-coefficient [aß] = 0.33, 95% confidence interval [CI] 0.02-0.65, p = 0.040) and conductive airways ventilation inhomogeneity [Scond ] (aß = 0.016, CI 0.004-0.028, p = 0.011) when compared with those with a RV negative bronchiolitis history (n = 45). In addition, we found a statistical interaction between RV bronchiolitis and bronchiolitis severity strengthening the association with LCI (aß = 0.93, CI 0.20-1.58, p = 0.006). CONCLUSION: Children with a history of hospital admission for RV positive bronchiolitis in infancy might be at a higher risk of lung ventilation inhomogeneities at preschool age, arising from the peripheral conducting airways.

Environmental risk factors for respiratory infection and wheeze in young children: A multicentre birth cohort study.

INTRODUCTION: Respiratory infections and wheeze have a considerable impact on the health of young children and consume significant healthcare resources. We aimed to evaluate the effect of environmental factors on respiratory infections and symptoms in early childhood. METHODS: Environmental risk factors including: daycare attendance; breastfeeding; siblings; damp within the home; environmental tobacco smoke (ETS); child's bedroom flooring; animal exposure; road traffic density around child's home; and solid fuel pollution within home were assessed in children recruited to the GO-CHILD multicentre prospective birth cohort study. Follow-up information on respiratory infections (bronchiolitis, pneumonia, otitis media and cold or flu), wheeze and cough symptoms, healthcare utilisation and medication prescription was collected by postal questionnaires at 12 and 24 months. Log binomial and ordered logistic regression models were fitted to the data. RESULTS: Follow-up was obtained on 1344 children. Daycare was associated with increased odds of pneumonia (odds ratio [OR] = 2.39, 95% confidence interval [CI]: 1.04-5.49), bronchiolitis (OR = 1.40, 1.02-1.90), otitis media (OR = 1.68, 1.32-2.14) and emergency department attendance for wheeze (RR = 1.81, 1.17-2.80). Breastfeeding beyond 6 months was associated with a reduced odds of bronchiolitis (OR = 0.55, 0.39-0.77) and otitis media (OR = 0.75, 0.59-0.99). Siblings at home was associated with an increased odds of bronchiolitis (OR = 1.65, 1.18-2.32) and risk of reliever inhaler prescription (RR = 1.37, 1.02-1.85). Visible damp was associated with an increased odds of wheeze (OR = 1.85, 1.11-3.19), and risk of reliever inhaler (RR = 1.73, 1.04-2.89) and inhaled corticosteroid prescription (RR = 2.61, 1.03-6.59). ETS exposure was associated with an increased odds of primary care attendance for cough or wheeze (OR = 1.52, 1.11-2.08). Dense traffic around the child's home was associated with an increased odds of bronchiolitis (OR = 1.32, 1.08-2.29). CONCLUSION: Environmental factors likely influence the wide variation in infection frequency and symptoms observed in early childhood. Larger population studies are necessary to further inform and guide public health policy to decrease the burden of respiratory infections and wheeze in young children.

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.

Effect Modifiers of the Association of High-Flow Nasal Cannula and Bronchiolitis Length of Stay.

BACKGROUND AND OBJECTIVES: High-flow nasal cannula (HFNC) therapy for hospitalized children with bronchiolitis is associated with a longer length of stay (LOS) when used outside of the ICU. We sought to explore the association between HFNC and LOS to identify if demographic and clinical factors may modify the effect of HFNC usage on LOS. METHODS: In this multicenter retrospective cohort study, we used a combination of hospital records and the Pediatric Health Information System. We included encounters from September 1, 2018 to March 31, 2020 for patients <2 years old diagnosed with bronchiolitis. Multivariable Poisson regression was performed for the association of LOS with measured covariates, including fixed main effects and interaction terms between HFNC and other factors. RESULTS: Of 8060 included patients, 2179 (27.0%) received HFNC during admission. Age group, weight, complex chronic condition, initial tachypnea, initial desaturation, and ICU services were significantly associated with LOS. The effect of HFNC on LOS differed among hospitals (P < .001), with the estimated increase in LOS ranging from 32% to 139%. The effect of HFNC on LOS was modified by age group, initial desaturation, and ICU services, with 1- to 6-month-old infants, patients without initial desaturation, and patients without ICU services having the highest association between HFNC and LOS, respectively. CONCLUSIONS: We identified multiple potential effect modifiers for the relationship between HFNC and LOS. The authors of future prospective studies should investigate the effect of HFNC usage on LOS in non-ICU patients without documented desaturation.

The impact of coronavirus disease 2019 pandemic on bronchiolitis (lower respiratory tract infection) due to respiratory syncytial virus: A systematic review and meta-analysis.

The coronavirus disease 2019 (COVID-19) pandemic has changed the epidemiology of respiratory syncytial virus (RSV) infection which accounts for most bronchiolitis and viral pneumonias in infants. This systematic review and meta-analysis aimed to quantitatively assess the effect of the COVID-19 pandemic on RSV-associated bronchiolitis among hospitalized infants. The study protocol was registered in the PROSPERO database (CRD42022314000) and was designed based on Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines updated in May 2020. The meta-analysis component was modified appropriately to synthesize the pooled proportion of infants having RSV-associated bronchiolitis before the COVID-19 pandemic in 2019 and during the pandemic with 95% confidence interval (CI). We identified and screened 189 articles and systematically reviewed 50 full texts. Eight qualified studies from Europe and China, including 109,186 symptomatic cases of bronchiolitis before the pandemic in 2019 and 61,982 cases in 2020-2021 were pooled by random-effects meta-analysis. The quantitative analysis included laboratory-confirmed RSV infection in 7691 infants with bronchiolitis reported before the pandemic in 2019. Meanwhile, during the pandemic, 4964 bronchiolitis cases were associated with RSV infection. The pooled proportion of RSV-associated bronchiolitis cases before the pandemic in 2019 was 16.74% (95% CI 11.73, 22.43%, 95% prediction interval 0.032, 34.16). The pooled proportion of confirmed RSV cases during the pandemic in 2020/2021 was 19.20% (95% CI 12.01, 27.59%, 95% prediction interval 0.046, 42.35). There was an increase in RSV activity after the relaxation of stringent public health measures during the COVID-19 pandemic.

Influencia de la pandemia COVID-19 sobre la epidemiología de la bronquiolitis aguda / Influence of the COVID-19 pandemic on the epidemiology of acute bronchiolitis

Introducción: La pandemia COVID-19ha modificado la propagación de ciertos virus respiratorios causantes de bronquiolitis aguda. Analizamos la epidemiología de los ingresos por bronquiolitis durante la pandemia COVID-19 en comparación con ocho temporadas epidémicas anteriores. Métodos: Estudio observacional ambispectivo, que incluyó lactantes con bronquiolitis ingresados en un hospital terciario durante dos períodos: pandemia COVID-19 (15 de marzo de 2020 a 31 de agosto de 2021) y pre-pandemia (1 de septiembre de 2012 a 14 de marzo de 2020). Se recogieron características demográficas, clínicas y etiología. Resultados: Ingresaron 510 pacientes por bronquiolitis: 486 en el período pre-pandemia con una media de 61 ingresos por temporada vs. 24 durante la pandemia, observándose una reducción de ingresos del 60,7%. Durante la pandemia, el brote epidémico se inició con retraso abarcando la primavera-verano de 2021. El virus respiratorio sincitial fue el agente etiológico más frecuente en ambos períodos. Conclusiones: Observamos un cambio estacional de la bronquiolitis durante la pandemia COVID-19, probablemente influenciado por las medidas de control frente a SARS-CoV-2.(AU)

Introduction: The COVID-19 pandemic has changed the circulation of some viruses associated with acute bronchiolitis. We analyzed the epidemiology of bronchiolitis admissions during the COVID-19 pandemic compared with 8 previous epidemic seasons. Methods: An observational and ambispective study was performed, including infants admitted with bronchiolitis in a tertiary hospital during 2 periods: COVID-19 pandemic (15th March 2020 to 3rd August 2021) and pre-pandemic (1st September 2012 to 14th March 2020). Demographic, clinical data and etiologies were collected. Results: Five hundred ten patients were hospitalized with bronchiolitis: 486 in the pre-pandemic period with an average of 61 admissions per season vs. 24 during the pandemic, observing a 60.7% reduction in bronchiolitis admissions. During the pandemic, bronchiolitis outbreak was delayed until spring–summer 2021. Respiratory syncytial virus was the most frequent etiological agent in both periods. Conclusion: We observed a change in the seasonality of bronchiolitis during the pandemic COVID-19, possibly influenced by control measures against SARS-CoV-2..(AU)

Bronchiolitis versus bronchopneumonia: navigating antibiotic use within the LRTI spectrum.

Bronchiolitis, a common reason for infant hospitalisation in South Africa (SA), is caused by viral pathogens. Bronchiolitis is typically an illness of mild to moderate severity that occurs in well-nourished children. Hospitalised SA infants frequently have severe disease and/or coexisting medical conditions, and these cases of bronchiolitis may have bacterial co-infection that requires antibiotic therapy. However, the existence of widespread antimicrobial resistance in SA warrants the judicious use of antibiotics. This commentary describes: (i) common clinical pitfalls leading to an incorrect diagnosis of bronchopneumonia; and (ii) considerations for antibiotic therapy in hospitalised infants with bronchiolitis. If antibiotics are prescribed, the indication for their use should be clearly stated, and antibiotic therapy must be stopped promptly if investigations indicate that bacterial co-infection is unlikely. Until more robust data emerge, we recommend a pragmatic management strategy to inform antibiotic use in hospitalised SA infants with bronchiolitis in whom bacterial co-infection is suspected.

Hypophosphatemia in infants with severe bronchiolitis and association with length of mechanical ventilation.

OBJECTIVES: Electrolyte disorders occurs frequently in children with bronchiolitis. The aim of the present study was to describe the frequency of hypophosphatemia and to evaluate its association with length of mechanical ventilation in infants admitted to a pediatric intensive care unit (PICU) with bronchiolitis. METHODS: This retrospective cohort study included infants aged between 7 days and 3 months admitted to a PICU between September 2018 and March 2020 and diagnosed with severe acute bronchiolitis requiring respiratory support. Infants with a chronic condition that could potentially be a confounding factor were excluded. The primary outcome was the frequency of hypophosphatemia (<1.55 mmol/L); the secondary outcomes were the frequency of hypophosphatemia during the PICU stay, and the association with length of mechanical ventilation (LOMV). RESULTS: Among the 319 infants admitted 178 had at least one phosphatemia value and were included in the study. The frequency of hypophosphatemia was 41% at PICU admission (61/148) and 46% during the PICU stay (80/172). The median [IQR] LOMV was significantly longer in children with hypophosphatemia at admission (109 [65-195] h vs. 67 [43-128] h, p = 0.007), and in multivariable linear regression lower phosphatemia at admission was associated with longer LOMV (p < 0.001) after controlling for severity (PELOD2 score) and weight. CONCLUSION: Hypophosphatemia was frequent in infants with severe bronchiolitis admitted to a PICU and was associated with a longer LOMV.

A case of diffuse panbronchiolitis caused by Mycoplasma amphoriforme.

Mycoplasma amphoriforme is a novel specie which was discovered in 2003 and associated with congenital immune deficiency. It has been described as an underlying cause of bronchopneumonia. There is limited description of the in vitro sensitivities. In this article, we present the first description of M. amphoriforme as the causative agent of diffuse panbronchiolitis in a patient with X-linked hypogammaglobulinema and bronchiectasis, with symptoms improved by treatment with azithromycin. We also describe the difficulty obtaining this organism through routine culture and the need to consider culture independent methods of recovery when the suspicion is high.

Respiratory Syncytial Virus Infection: An Update.

Respiratory syncytial virus (RSV) is a highly contagious respiratory virus that can cause mild to severe illness in children. It is the leading cause of lower respiratory tract infections (LRTI) in children under the age of one year, and it can also affect older children and adults, especially those with underlying medical conditions. In the post-COVID period, there seems to be an increase in the incidence, possibly due to 'immunity debt'. Symptoms of RSV infection in children may include fever, runny nose, and cough. In severe cases, it can lead to bronchiolitis (inflammation of the small airways in the lungs) or pneumonia (infection of the lungs). Most children with RSV infection recover within a week or two, but some may require hospitalization, especially those who are premature or have underlying medical conditions. As there is no specific treatment for RSV infection, supportive care is the mainstay of management. In severe cases, oxygen therapy or mechanical ventilation may be necessary. High flow nasal cannula seems to be beneficial. There have been promising advances in development of RSV vaccines; few trials in adults and pregnant women have reported encouraging results. The US FDA has approved two RSV vaccines for use in older adults (GSK's Arexvy and Pfizer's ABRYSVO).

Risk factors for recurrent wheezing after bronchiolitis.

BACKGROUND: This study aimed to determine whether there was an association between certain factors in patients with bronchiolitis and recurrent wheezing in childhood. METHOD: In 2021 we tracked children hospitalized for bronchiolitis at Chengdu Women's and Children's Central Hospital in 2017. The patients were classified into recurrent wheezing group (RWG) and non-recurrent wheezing group (NRWG). Possible risk factors including maternal age, school-age siblings, allergic history, atopic dermatitis, allergic rhinitis, atopic family history, severity of the condition, duration of hospitalization, nasopharyngeal secretions culture, blood eosinophil counts, FeNO and skin prick test were compared between the two groups. Continuous variables were analyzed by independent sample t-test for normal distribution and Mann-Whitney U-test for non-normal distribution. Categorical variables were tested using chi-square tests. Multifactor analysis was conducted by stepwise logistics regression analysis. RESULTS: In total 167 participants were included, of which 26 and 141 were in RWG and NRWG respectively. In RWG children represented higher maternal age (P = 0.02) and greater probability of allergic history, atopic dermatitis, allergic rhinitis, atopic family history (odds ratio [OR] = 4.0,3.7, 7.8, 10.9 respectively, P < 0.01). However, school-age siblings, severity of the condition, duration of hospitalization, blood eosinophil counts, fractional exhaled nitric oxide and skin prick test results seemed unrelated to recurrent wheezing. In the subgroup analysis of nasopharyngeal secretion culture, there were more Moraxella catarrhalis-positive in RWG(P = 0.043). Atopic dermatitis, allergic rhinitis and atopic family history were identified as independent risk factors for recurrent wheezing. CONCLUSION: Some children with bronchiolitis will develop recurrent wheezing, and the risk factors are allergic history, Moraxella catarrhalis infection or colonization, atopic dermatitis, allergic rhinitis and atopic family history; the latter three are independent risk factors.

Long-Term Follow-Up of Daily Life Functioning After Pediatric Intensive Care Unit Admission.

OBJECTIVE: To investigate the long-term impact of pediatric intensive care unit (PICU) admission on daily life functioning while exploring the potential mediating role of neurocognitive outcome. STUDY DESIGN: This cross-sectional observational study compared children aged 6-12 years with previous PICU admission (age ≤1 year) for bronchiolitis requiring mechanical ventilation ("patient group," n = 65) to demographically comparable healthy peers ("control group," n = 76). The patient group was selected because bronchiolitis is not expected to affect neurocognitive functioning in itself. Assessed daily life outcome domains were behavioral and emotional functioning, academic performance, and health-related quality of life (QoL). The role of neurocognitive outcomes in the relationship between PICU admission and daily life functioning was assessed by mediation analysis. RESULTS: The patient group did not differ from the control group regarding behavioral and emotional functioning but performed poorer on academic performance and school-related QoL (Ps ≤ .04, d = -0.48 to -0.26). Within the patient group, lower full-scale IQ (FSIQ) was associated with poorer academic performance and school-related QoL (Ps ≤ .02). Poorer verbal memory was associated with poorer spelling performance (P = .002). FSIQ mediated the observed effects of PICU admission on reading comprehension and arithmetic performance. CONCLUSIONS: Children admitted to the PICU are at risk for long-term adverse daily life outcomes in terms of academic performance and school-related QoL. Findings suggest that lower intelligence may contribute to academic difficulties after PICU admission. Findings underline the importance of monitoring daily life and neurocognitive functioning after PICU admission.

Association between Early Childhood Vitamin D Status and Age 6-Year Lung Function among Children with a History of Severe Bronchiolitis in Infancy.

Improving lung health in children requires understanding the risk factors for decreased lung function. Our objective was to investigate the association between serum 25-hydroxyvitamin D (25(OH)D) levels and lung function in children. We analyzed data from a prospective cohort of infants hospitalized with bronchiolitis (severe bronchiolitis), a group at high risk for developing childhood asthma. Children were followed longitudinally, and 25(OH)D and spirometry testing were conducted at ages 3 and 6, respectively. We used a multivariable linear regression adjusted for race/ethnicity, annual household income, premature birth, and secondhand smoke exposure to examine the association between serum 25(OH)D level and primary outcomes (percent predicted [pp] of forced expiratory volume in the first second (FEV1) and the forced vital capacity (FVC)) and secondary outcome (FEV1pp/FVCpp). Serum 25(OH)D level and age 6 spirometry were available for 363 children. In adjusted analyses comparing the highest quintile (Q5) of serum 25(OH)D (median 37 ng/mL) to the lowest quintile (Q1; median 18 ng/mL), FEV1pp was 6% lower (p = 0.03) in Q1. Likewise, FVCpp was 7% lower (p = 0.03) in Q1. There was no difference in FEV1pp/FVCpp across the serum 25(OH)D quintiles. Compared to children with higher vitamin D status at age 3, those with lower status had decreased FEV1pp and FVCpp at 6 years.

Serum bilirubin is associated with a reduced risk of subsequent recurrent wheezing following acute respiratory syncytial virus bronchiolitis.

BACKGROUND: Bilirubin is a potent antioxidant and anti-inflammatory molecule that has been shown to ameliorate airway inflammation. We aimed to study whether serum bilirubin is protective and can predict the development of subsequent recurrent wheezing in infants with severe respiratory syncytial virus (RSV) bronchiolitis. METHODS: The medical records of 188 infants who were hospitalized during an initial episode of severe RSV bronchiolitis at 6 months of age or less were retrospectively reviewed. Our main outcome of interest was the development of subsequent recurrent wheezing by the age of 3 years. Each infant's serum bilirubin concentration was extracted from their blood biochemical results. RESULTS: Seventy-one (37.8%) infants developed recurrent wheezing by the age of 3 and 117 (62.2%) did not. The serum total bilirubin, unconjugated bilirubin, and conjugated bilirubin levels at hospital admission were lower in infants who developed recurrent wheezing as compared to those who did not (p ＜ 0.001). The area under the receiver-operating characteristic curve of serum total bilirubin, unconjugated bilirubin, and conjugated bilirubin for the prediction of subsequent recurrent wheezing were 0.71 (95% confidence interval [CI], 0.64-0.78), 0.70 (95% CI, 0.63-0.78), and 0.67 (95% CI, 0.59-0.75), respectively. Higher admission serum total bilirubin levels were independently associated with a lower risk of development of subsequent recurrent wheezing (adjusted OR 0.17, p ＜ 0.001). CONCLUSION: During the first episode of severe RSV bronchiolitis in infants <6 months of age, moderately higher levels of serum bilirubin are associated with a reduced risk of developing subsequent recurrent wheezing by 3 years of age.