Alarmins and innate lymphoid cells 2 activation: A common pathogenetic link connecting respiratory syncytial virus bronchiolitis and later wheezing/asthma?

Severe respiratory syncytial virus (RSV) infection in infancy is associated with increased risk of recurrent wheezing in childhood. Both acute and long-term alterations in airway functions are thought to be related to inefficient antiviral immune response. The airway epithelium, the first target of RSV, normally acts as an immunological barrier able to elicit an effective immune reaction but may also be programmed to directly promote a Th2 response, independently from Th2 lymphocyte involvement. Recognition of RSV transcripts and viral replication intermediates by bronchial epithelial cells brings about release of TSLP, IL-33, HMGB1, and IL-25, dubbed "alarmins." These epithelial cell-derived proteins are particularly effective in stimulating innate lymphoid cells 2 (ILC2) to release IL-4, IL-5, and IL-13. ILC2, reflect the innate counterparts of Th2 cells and, when activate, are potent promoters of airway inflammation and hyperresponsiveness in RSV bronchiolitis and childhood wheezing/asthma. Long-term epithelial progenitors or persistent epigenetic modifications of the airway epithelium following RSV infection may play a pathogenetic role in the short- and long-term increased susceptibility to obstructive lung diseases in response to RSV in the young. Additionally, ILC2 function may be further regulated by RSV-induced changes in gut microbiota community composition that can be associated with disease severity in infants. A better understanding of the alarmin-ILC interactions in childhood might provide insights into the mechanisms characterizing these immune-mediated diseases and indicate new targets for prevention and therapeutic interventions.

Is secondary tracheomalacia associated with airway inflammation and infection?

BACKGROUND: Recurrent lower respiratory tract infections are among the most prevalent symptoms in secondary tracheomalacia due to mediastinal vascular anomalies (MVAs). It is not known whether this condition could result in persistent lower respiratory tract inflammation and subclinical infection. METHODS: A retrospective study was performed on records of children with tracheomalacia due to MVAs and recurrent respiratory infections who underwent computed tomography scan, bronchoscopy, and bronchoalveolar lavage (BAL) as part of their clinical evaluation. RESULTS: Thirty-one children were included in the study: 21 with aberrant innominate artery, four with right aortic arch, one with double aortic arch, and five with aberrant innominate artery associated with right aortic arch. Cytological evaluation of bronchoalveolar lavage fluid showed increased neutrophil percentages and normal lymphocyte and eosinophil proportions. Microorganism growth was detected in 13 BAL samples, with a bacterial load ≥104 colony-forming units/mL in eight (25.8%) of them. Most isolates were positive for Haemophilus influenzae. Bronchiectasis was detected in four children, all with BAL culture positive for H. influenzae. Four patients underwent MVA surgical correction and 27 conservative management, i.e., respiratory physiotherapy in all and high-dose amoxicillin/clavulanic acid (40 mg/kg/day) for 2-4 weeks in those with significant bacterial growth. There was an excellent outcome in most of them. CONCLUSIONS: Neutrophilic alveolitis is detectable in secondary tracheomalacia but is associated with a clinically significant bacterial load only in a quarter of the patients. Caution should be used regarding inappropriate antibiotic prescriptions to avoid the emergence of resistance, whilst airway clearance maneuvers and infection preventive measures should be promoted.

[Recent updates on the antibacterial clofoctol.] / Recenti aggiornamenti sull'antibatterico clofoctolo.

Due to the worry growing increase in bacterial antibiotic resistance and the scanty availability of new antibiotics, it is highly recommended to use not recently synthesized, but still active molecules. Clofoctol is a synthetic chemotherapeutic agent with a different mechanism of action, as compared with the other antibacterial molecules currently available. By reducing intracellular ATP, clofoctol inhibits the synthesis of bacterial cytoplasmic membrane peptidoglycans, inducing the arrest of cell wall synthesis, thus characterizing the molecule as a "membrane-acting agent". More recently, however, it has been shown that clofoctol is also able to induce apoptosis by inhibiting the translation of intracellular proteins. An important property of clofoctol is the rapidity of the antimicrobial effect, which allows the complete eradication of the pathogen and makes the development of resistance unlikely. Administered rectally, the drug rapidly accumulates in the tissues. Most of the clinical studies conducted on clofoctol concern the treatment of respiratory diseases in children. The drug appears to be more active in upper rather than in lower respiratory tract infections. Tolerability was reported to be good, with a low incidence of side effects.

Chronic respiratory disorders due to aberrant innominate artery: a case series and critical review of the literature.

BACKGROUND: Tracheal compression (TC) due to vascular anomalies is an uncommon, but potentially serious cause of chronic respiratory disease in childhood. Vascular slings are congenital malformations resulting from abnormal development of the great vessels; in this group of disorders the most prevalent entity is the aberrant innominate artery (AIA). Here we provide a report on diagnosis and treatment of AIA in nine children with unexplained chronic respiratory symptoms. We describe the cases, perform a literature review, and provide a discussion on the diagnostic workup and treatment that can help manage AIA. METHODS: Clinical history, diagnostic procedures and treatment before and after the AIA diagnosis were retrospectively reviewed in nine children (5 boys and 4 girls), who were referred for recurrent-to-chronic respiratory manifestations over 10 years (2012-2022). We performed a comprehensive report on the ongoing clinical course and treatment as well as an electronic literature search on the topic. RESULTS: Diagnoses at referral, before AIA was identified, were chronic dry barking cough associated with recurrent pneumonia (n = 8, 89%), lobar/segmental atelectasis (n = 3, 33%), atopic/non atopic asthma (n = 3, 33%); pneumomediastinum with subcutaneous emphysema complicated the clinical course in one case. When referred to our Unit, all patients had been previously treated with repeated antibiotic courses (n = 9, 100%), alone (n = 6, 67%) or combined with prolonged antiasthma medications (n = 3, 33%) and/or daily chest physiotherapy (n = 2, 22%), but reported only partial clinical benefit. Median ages at symptom onset and at AIA diagnosis were 1.5 [0.08-13] and 6 [4-14] years, respectively, with a relevant delay in the definitive diagnosis (4.5 years). Tracheal stenosis at computed tomography (CT) was ≥ 51% in 4/9 cases and ≤ 50% in the remaining 5 subjects. Airway endoscopy was performed in 4 cases with CT evidence of tracheal stenosis ≥ 51% and confirmed CT findings. In these 4 cases, the decision of surgery was made based on endoscopy and CT findings combined with persistence of clinical symptoms despite medical treatment. The remaining 5 children were managed conservatively. CONCLUSIONS: TC caused by AIA may be responsible for unexplained chronic respiratory disease in childhood. Early diagnosis of AIA can decrease the use of expensive investigations or unsuccessful treatments, reduce disease morbidity, and accelerate the path toward a proper treatment.

Lateral Thoracic Expansion for Jeune's Syndrome, Surgical Approach, and Technical Details.

INTRODUCTION: Jeune's syndrome, or asphyxiating thoracic dystrophy (ATD), is a rare autosomal recessive disorder characterized by skeletal dysplasia. Ribs are typically short and horizontal resulting-in lethal variant-in severe lung hypoplasia, progressive respiratory failure, and death. Lateral thoracic expansion (LTE) consists in staggered bilateral ribs osteotomy leading to chest expansion and lung development. Studies on LTE in ATD patients report encouraging data, but the rarity of ATD implies the lack of a standardized surgical path. The aim of this report is to present our experience with LTE, the technical modification we adopted, and patients' clinical outcome. MATERIALS AND METHODS: We retrospectively reviewed data of 11 LTE performed in 7 ATD patients with lethal variant. Information regarding pre- and postoperative clinical conditions and surgical details was collected. We adopted a single-stage or a two-stage approach based on patient clinical condition. Computed tomography (CT) scan was performed before and after surgery and lung volume was calculated. RESULTS: Five patients are alive, while two died in intensive care unit for other than respiratory cause (sepsis). Most patients experienced clinical improvement in terms of decreased respiratory infections rate, need for ventilation, and improved exercise tolerance. Postoperative CT scan demonstrated a median lung volume increase of 88%. CONCLUSION: Mortality in ADT patients is high. However, LTE is a feasible and safe surgical approach, which could improve clinical conditions and survival rate. Survived patients showed postoperatively less oxygen requirement and improved clinical conditions.

How has the SARS-CoV-2 pandemic changed the epidemiology and management of acute bronchiolitis?

OBJECTIVE: SARS-COV-2 pandemic profoundly impacted acute bronchiolitis epidemiology worldwide, especially respiratory syncytial virus (RSV) diffusion and the burden of disease, with remarkable implications on the management of health resources. We aimed to study the epidemiology and clinical course of bronchiolitis in the past 5 years in our region and to assess the trends that occurred during and after the SARS-COV-2 pandemic. METHODS: We conducted an observational study including all children aged 0-2 years with bronchiolitis admitted to a tertiary children's hospital during the last 5 years. Demographic, clinical, and microbiological data were collected. Comparisons between patient subgroups were carried out. RESULTS: A total of 647 patients admitted for bronchiolitis were included (median age 78 days). Molecular diagnostic tests were performed in 617 patients (95.4%) with RSV detected in 51.5% of patients in prepandemic years and 74.5% in pandemic years. Through the study period, we observed a progressive increase in the number of children requiring respiratory support, RSV infections, and children with a history of prematurity. Conversely, this was not true for mechanical ventilation, duration of respiratory support, intensive care unit admission, and length of stay. CONCLUSIONS: Clinical course and epidemiology of bronchiolitis showed a significant change through the study years with a heavy impact during the 2021-2022 season. The increase in the number of patients requiring respiratory support, although not associated with an increase in mechanical ventilation, may be explained by the higher prevalence of RSV. The change in epidemiology highlights the importance of surveillance systems to monitor RSV circulation, to plan prophylactic strategies, and prepare healthcare systems.

A new SPINK5 mutation in a patient with Netherton syndrome: a case report.

We report on a case of Netherton syndrome showing a new SPINK5 mutation (c.957_960dupTGGT duplication in exon 11), associated with partial defect of biotinidase.

Working as a team in airway surgery: History, present and perspectives.

Teamwork is one of the most important trend in modern medicine. Airway team were created in many places to respond in a multidisciplinary and coordinated way to challenging clinical problems which were beyond the possibility of an individual management. In this chapter, we illustrate the historical steps leading to the development of an airway team in a pediatric referral hospital, describe the present teamwork activity defining the key points for the creation of a team and discussing different organization models; finally we delineate possible future directions for the airway teams in the globalized world.

Emergency percutaneous, bicaval double-lumen, ECMO cannulation in neonates and infants: insights from three consecutive cases.

BACKGROUND: Veno-venous extracorporeal membrane oxygenation (ECMO) is probably the preferable configuration to assist children with respiratory failure who do not respond to maximized conventional therapies. The single-vessel, double-lumen approach through the internal jugular vein is extremely advantageous, especially in infants, where femoral access presents limitations related to the small dimensions of the veins. In case of emergencies, ECMO might need to be started at the bedside, without the availability of fluoroscopic guidance. To our knowledge, a completely percutaneous approach has not been reported before in children younger than 1 year and weighing less than 5 kg. METHODS: We describe 3 cases of emergency bedside, percutaneous, bicaval double-lumen cannulation under real-time transthoracic ultrasound control in 2 neonates and 1 infant. RESULTS: In our experience, this approach proved to be safe, effective and time saving, while minimizing bleeding from the cannula insertion site. Cannulation times, from decision making to the beginning of ECMO flow, were 30, 28, 25 minutes respectively, from patient 1 to 3. We do not report any cannula-related injury to vessels and heart structures. CONCLUSIONS: Our preliminary data suggest that, with the described precautions, percutaneous, echo-guided, bicaval double-lumen cannulation in neonates and infants could be effective and free from major complications. Further evaluation should be warranted in the neonatal population.