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.

Air pollution and bronchiolitis: a case-control study in Antwerp, Belgium.

This case-control study aimed to investigate the association between short-term (1 to 5 days) and medium-term (31 days) exposure to air pollutants (PM2.5, PM10, BC, NO2) at home/daycare and the risk of 'severe bronchiolitis' (defined as 'requiring hospitalization for bronchiolitis') in children under 2 years in Antwerp, Belgium. We included 118 cases and 79 controls admitted to three general hospitals from October 2020 to June 2021. Exposure levels were predicted using an interpolation model based on fixed measuring stations. We used unconditional logistic regression analysis to assess associations, with adjustment for potential confounders. There were hardly any significant differences in the day-to-day air pollution values between cases and controls. Medium-term (31 days) exposure to PM2.5, PM10, and NO2 was however significantly higher in cases than controls in univariate analysis. Logistic regression revealed an association between severe bronchiolitis and interquartile range (IQR) increases of PM2.5 and PM10 at home and in daycare, as well as IQR increases of NO2 in daycare. Controls were however overrepresented in low pollution periods. Time-adjustment reduced the odds ratios significantly at home for PM2.5 and PM10 (aOR 1.54, 95%CI 0.51-4.65; and 2.69, 95%CI 0.94-7.69 respectively), and in daycare for. PM2.5 (aOR 2.43, 95%CI 0.58-10.1). However, the association between severe bronchiolitis and medium-term air pollution was retained in daycare for IQR increases of PM10 (aOR 5.13, 95%CI 1.24-21.28) and NO2 (aOR 3.88, 95%CI 1.56-9.61) in the time-adjusted model.  Conclusion: This study suggests a possible link between severe bronchiolitis and medium-term (31 days) air pollution exposure (PM10 and NO2), particularly in daycare. Larger studies are warranted to confirm these findings. What is Known: • Bronchiolitis is a leading cause of hospitalization in infants globally and causes a yearly seasonal wave of admissions in paediatric departments worldwide. • Existing studies, mainly from the USA, show heterogeneous outcomes regarding the association between air pollution and bronchiolitis. What is New: • There is a possible link between severe bronchiolitis and medium-term (31 days) air pollution exposure (PM10 and NO2), particularly in daycare. • Larger studies are needed to validate these trends.

[Influencia de la pandemia de la COVID-19 en la distribución de la bronquiolitis aguda en España.] / Influencia de la pandemia de la COVID-19 en la distribución de la bronquiolitis aguda en España.

OBJECTIVE: Bronchiolitis is the leading cause of hospitalization in children under one year of age, with annual epidemics. Since the onset of the SARS-CoV-2 coronavirus disease pandemic (COVID-19), there has been a change in the transmission of other respiratory viruses. Our aim in this paper was to describe how COVID-19 had affected the distribution of acute bronchiolitis in our country. METHODS: We conducted a retrospective descriptive study of the cases of bronchiolitis treated in a sample of Spanish hospitals belonging to four autonomous communities. A chi-square test and Student's t- test were used to compare epidemiological and demographic variables between patients attending the hospital with bronchiolitis during January 2021-June 2021 with patients attending the hospital in the previous three years (2018-2020). RESULTS: We analyzed 6,124 cases of bronchiolitis (58.8% males and 41.2% females). The mean age was 0.5 years (SD: 0.4). In 2020, we observed a decrease of bronchiolitis cases compared to 2019 of 67%. During 2020 and 2021, the epidemic season started in January-February and peaked in June. During the first half of 2021, the highest percentage of admissions for bronchiolitis associated with RSV infection was observed in hospitals in central Spain corresponding to the Autonomous Community of Madrid (78.5% of admissions). CONCLUSIONS: The COVID-19 pandemic significantly modifies the seasonality of bronchiolitis. In our country, the flow and distribution of the disease are not uniform. It starts in the center of Spain and ends on the coast.

OBJETIVO: La bronquiolitis es la primera causa de hospitalización en menores de un año, presentándose en forma de epidemias anuales. Desde el inicio de la pandemia por la enfermedad causada por el coronavirus SARS-CoV-2 (COVID-19) se ha producido un cambio en la transmisión de otros virus respiratorios. Nuestro objetivo en este trabajo fue describir cómo había afectado la pandemia de la COVID-19 a la distribución de la bronquiolitis aguda en nuestro país. METODOS: Realizamos un estudio descriptivo retrospectivo de los casos de bronquiolitis atendidos en una muestra de hospitales españoles que pertenecían a cuatro comunidades autónomas. Empleado el test chi-cuadrado y la prueba t de Student comparamos variables epidemiológicas y demográficas de los casos de bronquiolitis atendidos durante enero de 2021 y junio 2021, con los tres años anteriores (2018-2020). RESULTADOS: Analizamos 6.124 casos de bronquiolitis (58,8% varones y 41,2% mujeres). La media de edad fue de 0,5 años (DE: 0,4). En 2020 observamos un descenso de casos de bronquiolitis con respecto a 2019 del 67%. Durante 2020 y 2021 la temporada epidémica empezó en enero-febrero y alcanzó su pico máximo en junio. Durante el primer semestre de 2021, el porcentaje más elevado de ingresos por bronquiolitis asociados a infección VRS fue observado en hospitales del centro de España correspondientes a la Comunidad Autónoma de Madrid (78,5% de los ingresos). CONCLUSIONES: La pandemia por la COVID-19 modifica de manera significativa la estacionalidad de la bronquiolitis. En nuestro país, el flujo y distribución de la enfermedad no es uniforme, comenzado por el centro peninsular y, por último, la zona litoral.

Nasopharyngeal fungal subtypes of infant bronchiolitis and disease severity risk.

BACKGROUND: Bronchiolitis is a leading cause of infant hospitalization. Recent research suggests the heterogeneity within bronchiolitis and the relationship of airway viruses and bacteria with bronchiolitis severity. However, little is known about the pathobiological role of fungi. We aimed to identify bronchiolitis mycotypes by integrating fungus and virus data, and determine their association with bronchiolitis severity and biological characteristics. METHODS: In a multicentre prospective cohort study of 398 infants (age <1 year, male 59%) hospitalized for bronchiolitis, we applied clustering approaches to identify mycotypes by integrating nasopharyngeal fungus (detected in RNA-sequencing data) and virus data (respiratory syncytial virus [RSV], rhinovirus [RV]) at hospitalization. We examined their association with bronchiolitis severity-defined by positive pressure ventilation (PPV) use and biological characteristics by nasopharyngeal metatranscriptome and transcriptome data. RESULTS: In infants hospitalized for bronchiolitis, we identified four mycotypes: A) fungiM.restrictavirusRSV/RV, B) fungiM.restrictavirusRSV, C) fungiM.globosavirusRSV/RV, D) funginot-detectedvirusRSV/RV mycotypes. Compared to mycotype A infants (the largest subtype, n = 211), mycotype C infants (n = 85) had a significantly lower risk of PPV use (7% vs. 1%, adjOR, 0.21; 95% CI, 0.02-0.90; p = 0.033), while the risk of PPV use was not significantly different in mycotype B or D. In the metatranscriptome and transcriptome data, mycotype C had similar bacterial composition and microbial functions yet dysregulated pathways (e.g., Fc γ receptor-mediated phagocytosis pathway and chemokine signaling pathway; FDR <0.05). INTERPRETATION: In this multicentre cohort, fungus-virus clustering identified distinct mycotypes of infant bronchiolitis with differential severity risks and unique biological characteristics. FUNDING: This study was supported by the National Institutes of Health.

Exposure to outdoor air pollution and risk of hospitalization for bronchiolitis in an urban environment: A 9-year observational study.

BACKGROUND: Outdoor air pollution is supposed to influence the course of bronchiolitis, but the evidence is limited. The present study aimed at evaluating the role of outdoor air pollutants on hospitalization for bronchiolitis. METHODS: Infants aged ≤12 months referred for bronchiolitis to our Pediatric Emergency Department in Bologna, Italy, from 1 October 2011 to 16 March 2020 (nine epidemic seasons) were retrospectively included. Daily concentrations of benzene (C6 H6 ), nitrogen dioxide (NO2 ), particulate matter ≤2.5 µm (PM2.5 ), and ≤10 µm (PM10 ), and the mean values of individual patient exposure in the week and the 4 weeks before hospital access were calculated. The association between air pollutants exposure and hospitalization was evaluated through logistic regression analysis. RESULTS: A total of 2902 patients were enrolled (59.9% males; 38.7% hospitalized). Exposure to PM2.5 in the 4 weeks preceding bronchiolitis was identified as the main parameter significantly driving the risk of hospitalization (odds ratio [95% confidence interval]: 1.055 [1.010-1.102]). After stratifying by season, higher values of other outdoor air pollutants were found to significantly affect hospitalization: 4-week exposure to C6 H6 (Season 2011-2012, 4.090 [1.184-14.130]) and PM2.5 (Season 2017-2018, 1.282 [1.032-1.593]), and 1-week exposure to C6 H6 (Season 2012-2013, 6.193 [1.552-24.710]), NO2 (Season 2013-2014, 1.064 [1.009-1.122]), PM2.5 (Season 2013-2014, 1.080 [1.023-1.141]), and PM10 (Season 2018-2019, 1.102 [0.991-1.225]). CONCLUSION: High levels of PM2.5 , C6 H6 , NO2 , and PM10 may increase the risk of hospitalization in children affected by bronchiolitis. Open-air exposure of infants during rush hours and in the most polluted areas should be avoided.

Smoking-Related Interstitial Lung Diseases.

Smoking-related interstitial lung diseases (ILDs) are a group of heterogeneous, diffuse pulmonary parenchymal disease processes associated with tobacco exposure. These disorders include pulmonary Langerhans cell histiocytosis, respiratory bronchiolitis-associated ILD, desquamative interstitial pneumonia, acute eosinophilic pneumonia, and combined pulmonary fibrosis and emphysema. This review summarizes the current evidence of pathogenesis, clinical manifestations, diagnostic approach, prognosis, and treatment modalities for these diseases. We also discuss the interstitial lung abnormalities incidentally detected in radiologic studies and smoking-related fibrosis identified on lung biopsies.

Dual inhibition of the MEK/ERK and PI3K/AKT pathways prevents pulmonary GVHD suppressing perivenulitis and bronchiolitis.

Patients with pulmonary graft-versus-host disease (pGVHD) have a poor prognosis after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Furthermore, pGVHD pathogenesis is not fully elucidated in humans, and currently available immunosuppressants are inadequately effective. We performed pathologic evaluation of lung specimens from 45 allo-HSCT recipients with pGVHD who underwent lung transplantation. Patient pathology was characterized by bronchiolitis and subpleural perivascular inflammation, with B-cell, monocyte, and T-cell accumulation around bronchioles. Bronchiolitis, perivascular inflammation, and peribronchial macrophage aggregation were also identified in a murine pGVHD model after transplant of bone marrow cells and splenocytes from C57BL/6 to B10.BR mice. Among mitogen-activated protein kinase kinase (MEK) inhibitors, cobimetinib, but not trametinib, improved survival rates. Cobimetinib attenuated bronchiolitis, improved airway resistance and lung compliance in the mice, and suppressed activation of B cells and tumor necrosis factor α production by monocytes in vitro; these features were not suppressed by trametinib or tacrolimus. Furthermore, cobimetinib suppressed activation of phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) signaling, resulting in B-cell and monocyte suppression. Dual inhibition of the MEK/extracellular signal-regulated kinase (ERK) and PI3K/AKT pathways using a combination of trametinib and the PI3K inhibitor taselisib strongly suppressed B-cell activation in vitro and improved mouse survival rates compared with vehicle or monotherapy with trametinib or taselisib. Imaging mass cytometry of human pGVHD revealed that T cells around bronchioles were positive for phosphorylated ERK, whereas B cells were positive for phosphorylated AKT. Thus, perivascular inflammation and bronchiolitis mediated by activation of the MEK/ERK and PI3K/AKT pathways are essential for pGVHD and represent a potential novel therapeutic target in humans.

Evaluation of the Interstitial Histological Lesions in Pulmonary Langerhans Cell Histiocytosis.

OBJECTIVE: Pulmonary Langerhans cell histiocytosis is a cystic lung disease characterized by the proliferation of parenchymal dendritic cells. The disease can become chronic or even cause pulmonary fibrosis. Our aim in this study was to investigate the typical histological findings and interstitial fibrosis in pulmonary Langerhans cell histiocytosis cases. MATERIAL AND METHOD: In the study, cases that had undergone diagnostic resection were screened. Smoking, histological stage (subacute, subacute-chronic), and cystic and eosinophilic granulomas were confirmed in the cases. In addition to emphysema, chronic nonspecific bronchiolitis, interstitial fibrosis (subpleural-paraseptal fibrosis, peribronchial fibrosis, fibrotic nonspecific interstitial pneumonia), honeycomb-type fibrocysts, and unexpected lesions were investigated. Descriptive and comparative (Fisher exact test) statistical analyses were used in the study (p < 0.05). RESULTS: A total of 27 cases were detected; age distribution was 17-68 (36.4). Smoking was present in 15 (55.5%) cases. Six (22.2%) cases were subacute, and 21 (7.7%) cases were subacute-chronic histological stage. A cystic lesion was present in 22 (81.4%) cases. All cases had emphysema accompanying the underlying lesions. Chronic nonspecific bronchiolitis was detected in 14 (51.8%) cases. Interstitial fibrosis was detected in 8 (29.6%) patients. Compared to interstitial fibrosis and nonfibrosis, there was no significant difference between being younger than 39 years, gender, smoking, and histological stage (p=0.41; 1; 0.69; 0.63, respectively). CONCLUSION: There is a risk of developing interstitial fibrosis patterns and honeycomb-type fibrocysts in the progression of pulmonary Langerhans cell histiocytosis. Histopathological evaluation can play an important role in the detection of risk groups.

Roles of Ambient Temperature and PM2.5 on Childhood Acute Bronchitis and Bronchiolitis from Viral Infection.

Studies have associated the human respiratory syncytial virus which causes seasonal childhood acute bronchitis and bronchiolitis (CABs) with climate change and air pollution. We investigated this association using the insurance claims data of 3,965,560 children aged ≤ 12 years from Taiwan from 2006−2016. The monthly average incident CABs increased with increasing PM2.5 levels and exhibited an inverse association with temperature. The incidence was 1.6-fold greater in January than in July (13.7/100 versus 8.81/100), declined during winter breaks (February) and summer breaks (June−August). The highest incidence was 698 cases/day at <20 °C with PM2.5 > 37.0 µg/m3, with an adjusted relative risk (aRR) of 1.01 (95% confidence interval [CI] = 0.97−1.04) compared to 568 cases/day at <20 °C with PM2.5 < 15.0 µg/m3 (reference). The incidence at ≥30 °C decreased to 536 cases/day (aRR = 0.95, 95% CI = 0.85−1.06) with PM2.5 > 37.0 µg/m3 and decreased further to 392 cases/day (aRR = 0.61, 95% CI = 0.58−0.65) when PM2.5 was <15.0 µg/m3. In conclusion, CABs infections in children were associated with lowered ambient temperatures and elevated PM2.5 concentrations, and the high PM2.5 levels coincided with low temperature levels. The role of temperature should be considered in the studies of association between PM2.5 and CABs.

Climate seasonality and lower respiratory tract diseases: a predictive model for pediatric hospitalizations.

OBJECTIVES: to analyze the climate seasonality of respiratory diseases in children aged 0-9 years and present a model to predict hospital admissions for 2021 to 2022. METHODS: verify, in a temporal manner, the correlation of admissions for pneumonia, bronchitis/bronchiolitis, and asthma with meteorological variables, aiming to demonstrate seasonality with the adjustment of temporal series models. RESULTS: there was a seasonal effect in the number of registered cases for all diseases, with the highest incidence of registrations in the months of autumn and winter. CONCLUSIONS: it was possible to observe a tendency towards a decrease in the registration of pneumonia cases; In cases of admissions due to bronchitis and bronchiolitis, there was a slight tendency towards an increase; and, in occurrence rates of asthma, there was no variation in the number of cases.

Safety and effectiveness of bubble continuous positive airway pressure as respiratory support for bronchiolitis in a pediatric ward.

The results of several clinical trials suggest that continuous positive airway pressure (CPAP) for acute bronchiolitis can be more effective than high-flow nasal cannula (HFNC). The use of HFNC involved a minimum reduction (5%) in admissions to the pediatric intensive care unit (PICU) in our hospital. Our main aim was to evaluate its safety and effectiveness as respiratory support for patients with bronchiolitis in a pediatric general ward. A secondary goal was to compare the admissions to PICU and the invasive mechanical ventilation (IMV) rate of patients treated with HFNC and those treated with HFNC/b-CPAP during the 2018-2019 and 2019-2020 epidemic seasons, respectively. Two prospective single-centre observational studies were performed. For the main aim, a cohort study (CS1) was carried out from 1st of November 2019 to 15th of January 2020. Inclusion criteria were children aged up to 3 months with bronchiolitis treated with b-CPAP support when HFNC failed. Epidemiological and clinical parameters were collected before and 60 min after the onset of CPAP and compared between the responder (R) and non-responders (NR) groups. NR was the group that required PICU admission. One hundred fifty-eight patients were admitted to the ward with bronchiolitis and HFNC. Fifty-seven out of one hundred fifty-eight required b-CPAP. No adverse events were observed. Thirty-two out of fifty-seven remained in the general ward (R-group), and 25/57 were admitted to PICU (NR-group). There were statistically significant differences in respiratory rate (RR) and heart rate (HR) between both groups before and after the initiation of b-CPAP, but the multivariable models showed that the main differences were observed after 60 min of therapy (lower HR, RR, BROSJOD score and FiO2 in the R-group). For the secondary aim, another cohort study (CS2) was performed comparing data from a pre-b-CPAP bronchiolitis season (1st of November 2018 to 15th January 2019) and the b-CPAP season (2019-2020). Inclusion criteria in pre-b-CPAP season were children aged up to 3 months admitted to the same general ward with moderate-severe bronchiolitis and with HFNC support. Admissions to PICU during the CPAP season were significantly reduced, without entailing an increase in the rate of IMV. CONCLUSION: The implementation of b-CPAP for patients with bronchiolitis in a pediatric ward, in whom HFNC fails, is safe and effective and results in a reduction in PICU admissions. WHAT IS KNOWN: • Bronchiolitis is one of the most frequent respiratory infections in children and one of the leading causes of hospitalization in infants. • Several studies suggest that the use of continuous positive airway pressure (CPAP) for acute bronchiolitis can be more effective than the high flow nasal cannula (HFNC). CPAP is a non-invasive ventilation (NIV) therapy used in patients admitted to pediatric intensive care unit (PICU) with progressive moderate-severe bronchiolitis. There is little experience in the literature on the use of continuous positive airway pressure (CPAP) for acute bronchiolitis in a general ward. WHAT IS NEW: • CPAP could be safely and effectively used as respiratory support in young infants with moderate-severe bronchiolitis in a general ward and it reduced the rate of patients who required PICU admission. • Patients' heart and respiratory rate and their FiO2 needs in the first 60 minutes may help to decide whether or not to continue the CPAP therapy in a general ward.

Modifiable environmental factors predispose term infants to bronchiolitis but bronchiolitis itself predisposes to respiratory sequelae.

INTRODUCTION: Viral bronchiolitis is a common lower respiratory tract infection in infants. Environmental and genetic factors can favor respiratory tract infections. AIM: The aim of this study is to analyze risk factors for bronchiolitis and to investigate the predisposing factors for developing transient wheezing and asthma through a 6-year follow-up after hospitalization for bronchiolitis compared with a group of healthy controls that belonged to Piccolipiù cohort, who never had bronchiolitis. METHODS: We enrolled 645 infants hospitalized with bronchiolitis. A structured questionnaire was used to obtain demographic and clinical data. At 6 years of age, 370 cases and 183 controls were investigated for the presence of asthma by the structured questionnaire, for prick test and for spirometry, and were classified to asthmatic, transient wheezing, and no wheezing/no asthma. RESULTS: Breastfeeding was an independent protective factor (odds ratio [OR]: 0.3, 95% confidence interval [95% CI]: 0.2-0.4, p < 0.001) and tobacco smoke was a risk factor for the development of bronchiolitis (OR: 2.1, 95% CI: 1.4-3.1, p < 0.001). Analyzing follow-up, bronchiolitis increased the risk of developing transient wheezing by 12.9 (95% CI: 6.3-26.1, p < 0.001) and of developing asthma by 4.6 (95% CI: 1.9-10.7, p < 0.001). A positive family history of atopy increased the risk of developing asthma by 3.1 (95% CI: 1.4-6.7, p = 0.005). Asthmatic patients had a lower % FEV1, a lower % flow-volume curve (FVC), and a lower FEV1/FVC value, and they had more frequently positive skin prick test. CONCLUSION: Bronchiolitis is influenced by environmental factors: tobacco smoke increases its risk and breastfeeding is a protective factor. At the end of 6 years of follow-up, bronchiolitis is a significant risk factor to have pre-school wheezing and asthma.

Diffuse Panbronchiolitis After Lung Transplantation: First Case in the Literature.

BACKGROUND: Diffuse panbronchiolitis is a chronic airway disease characterized by diffuse inflammation of respiratory bronchioles and peribronchial tissue. We present a case of diffuse panbronchiolitis developed after lung transplantation, which to our knowledge has not been previously described in the literature. CASE REPORT: A 52-year-old white woman was admitted with reports of weakness, shortness of breath, and productive cough 6 months after bilateral sequential lung transplantation. Thorax computed tomography revealed the appearance of a budding branch pattern in the lower lobes of both lungs. Repeated transbronchial lung biopsies were not diagnostic. A lower lobe wedge biopsy with thoracotomy was performed in the patient, whose respiratory function gradually deteriorated. Dense lymphocyte infiltration in the respiratory bronchiole wall and foamy macrophage groups in the adjacent interstitial area were detected in the histopathologic sections. The dramatic response was achieved with pulse steroid therapy in a short time. Rapidly worsening clinical course and response to the pulse steroid therapy suggested acute cellular rejection. CONCLUSIONS: Acute cellular rejection is expected within the first year in lung transplant recipients. Diffuse panbronchiolitis may be a kind of clinical presentation in lung recipients and should be considered in patients who develop severe graft function loss in a short time.

A Bayesian approach to real-time spatiotemporal prediction systems for bronchiolitis.

Respiratory Syncytial Virus (RSV) induced bronchiolitis is a common lung infection and a major cause of infant hospitalization and mortality. Unfortunately, there is no known cure for RSV but several vaccines are in various stages of clinical trials. Currently, immunoprophylaxis is a preventative measure consisting of a series of monthly shots that should be administered at the start, and throughout, peak RSV season. Thus, the successful implementation of immunoprophylaxis is contingent upon understanding when outbreak seasons will begin, peak, and end. In this research we estimate the seasonal epidemic curves of RSV induced bronchiolitis using a spatially varying change point model. Further, in a novel approach and using the fitted change point model, we develop a historical matching algorithm to generate real time predictions of seasonal curves for future years.

Severity of bronchiolitis in infants is associated with their parents' tobacco habit.

The aim of this study was to investigate the effect of tobacco smoke exposure among severely pediatric ICU patients. A prospective epidemiological observational study was conducted among children with bronchiolitis younger than 2 years of age admitted to the Pediatric Intensive Care Unit of Children's University Hospital La Paz during the October 2017 to March 2018 outbreak. On admission, parents were asked whether they smoked. In children who required invasive mechanical ventilation, endotracheal aspirate was collected at the time of intubation. A total of 102 patients with bronchiolitis were studied. Among these, 14 (47%) of 30 infants whose parents smoked required invasive mechanical ventilation vs. 14 (19%) of 72 whose parents were nonsmokers (p = 0.007). Among patients on invasive mechanical ventilation, 10 (71%) of 14 infants with secondhand smoke exposure presented pulmonary bacterial superinfection vs. 3 (21%) of 14 in the unexposed (p = 0.012).Conclusion: Secondhand smoke exposure is an additional high risk for pulmonary bacterial superinfection and invasive mechanical ventilation in infants with severe acute bronchiolitis What is known: •Environmental tobacco smoke exposure is known to be an important risk factor for childhood lower respiratory tract infections. •Tobacco smoke makes structural changes in the respiratory tract and reduces the immune response. What in new: •Secondhand smoke exposure showed to be associated with the increased need and duration of invasive mechanical ventilation, and pediatric intensive care length of stay. •Tobacco smoke exposure is an additional risk factor for the presence of bacteria in the endotracheal aspirate.

High-resolution CT in smoking-related interstitial lung diseases.

In addition to chronic obstructive pulmonary disease (COPD) and bronchogenic carcinoma, smoking can also cause interstitial lung diseases (ILDs) such as respiratory bronchiolitis (RB), RB with ILD (RB-ILD), desquamative interstitial pneumonia (DIP), Langerhans cell granulomatosis (LCG) and idiopathic pulmonary fibrosis-usual interstitial pneumonia (IPF-UIP). However, smoking seems to have a protective effect against hypersensitivity pneumonitis (HP), sarcoidosis and organising pneumonia (OP). High-resolution computed tomography (HRCT) has a pivotal role in the differential diagnosis. RB is extremely frequent in smokers, and is considered a marker for smoking exposure. It has no clinical relevance in itself since most patients with RB are asymptomatic. It is frequent to observe the association of RB with other smoking-related diseases, such as LCG or pulmonary neoplasms. In RB-ILD, HRCT features are more conspicuous and diffuse than in RB, but there is no definite cut-off between the two entities and any distinction can only be made by integrating imaging and clinical data. RB, RB-ILD and DIP may represent different degrees of the same pathological process, consisting in a bronchiolar and alveolar inflammatory reaction to smoking. Smoking is also a well-known risk factor for pulmonary fibrosis. Multidisciplinary discussion and follow-up can generally solve even the most difficult cases.

Pediatrician intervention impacts parental smoking in cystic fibrosis, diabetes, and bronchiolitis.

BACKGROUND: Child exposure to cigarette smoke is harmful. It should be reduced through parental smoking cessation interventions. The aim of our study was to determine the impact of simple advice provided by the pediatrician on the smoking habits of parents of children with cystic fibrosis (CF), diabetes mellitus (DM), and infants hospitalized for bronchiolitis. METHODS: Parents were interviewed on their smoking habits. Smoking cessation advice was provided by the pediatrician. A new smoking habits assessment was done at 3 months by phone interviews. RESULTS: A total of 260 parents were interviewed (91 in the CF group, 136 in the DM group, and 33 in the bronchiolitis group). A total of 70 parents were active smokers: 33% of parents of children with CF, 23.5% of parents of children with DM, and 24.2% for those with infants hospitalized for bronchiolitis (p = .42). In the CF group, smoking cessation had been significantly more frequently discussed with the medical team previously. A total of 67 smoking parents (95.7%) answered the 3-month assessment: 29.8% reported having started a smoking cessation process; 10.4% had quit smoking. The quitting rate was significantly higher in the groups of patients followed for a respiratory disorder (37.5% for bronchiolitis, 15% for CF vs. 0% for DM, p = .005). CONCLUSION: This study shows the important role that information and simple advice from pediatricians can have in initiating smoking cessation in parents of patients followed in specialized clinics or who are hospitalized, with a greater efficiency in parents of patients suffering from lung disorders.

Personal and Environmental Risk Factors at Birth and Hospital Admission: Direct and Vitamin D-Mediated Effects on Bronchiolitis Hospitalization in Italian Children.

Seasonal variations in UV-B radiation may influence vitamin D status, and this, in turn, may influence the risk of bronchiolitis hospitalization. The aim of this study was using a causal inference approach to investigate, simultaneously, the interrelationships between personal and environmental risk factors at birth/hospital admission (RFBH), serum vitamin D levels and bronchiolitis hospitalization. A total of 63 children (<2 years old) hospitalized for bronchiolitis (34 RSV-positive) and 63 controls were consecutively enrolled (2014-2016). Vitamin D levels and some RFBH (birth season, birth weight, gestational age, gender, age, weight, hospitalization season) were recorded. The discovered RFBH effects on the risk ok bronchiolitis hospitalization were decomposed into direct and vitamin-D mediated ones through Mediation Analysis. Winter-spring season (vs. summer-autumn) was significantly associated with lower vitamin D levels (mean difference -11.14 nmol/L). Increasing serum vitamin D levels were significantly associated with a lower risk of bronchiolitis hospitalization (OR = 0.84 for a 10-nmol/L increase). Winter-spring season and gestational age (one-week increase) were significantly and directly associated with bronchiolitis hospitalization (OR = 6.37 and OR = 0.78 respectively), while vitamin D-mediated effects were negligible (1.21 and 1.02 respectively). Using a comprehensive causal approach may enhance the understanding of the complex interrelationships among RFBH, vitamin D and bronchiolitis hospitalization.

Coronavirus HKU 1 infection with bronchiolitis, pericardial effusion and acute respiratory failure in obese adult female.

Seven species of coronavirus cause acute respiratory illness in humans. Coronavirus HKU 1 (CoV HKU 1) was first described in 2005 in an adult patient with pneumonia in Hong Kong. Although it is a well-known respiratory tract pathogen, there is not much information about its role in hospitalized adults, especially in southern Europe. Here, we describe a case of radiologically demonstrated CoV HKU 1-related bronchiolitis with acute respiratory failure in an adult female without significant comorbidities except obesity.