Introduction of the pneumococcal conjugate vaccine in humanitarian and fragile contexts: Perspectives from stakeholders in four African countries

Childhood pneumonia causes a significant burden of preventable child morbidity and mortality in Chad, Guinea, Somalia/Somaliland, and South Sudan. Leaders from these countries have committed to reducing this burden and are preparing to introduce the pneumococcal conjugate vaccine (PCV) into their immunization programs. To support long-term sustainability for expected PCV introductions in settings afflicted by prolonged humanitarian crises this research explores national stakeholders' perspectives on contextual factors that may influence optimal vaccine implementation. This qualitative study used purposive sampling to identify and interview stakeholders involved in vaccine decision-making. Interview transcripts were analyzed through the framework method, an approach involving charting data into pre-populated matrices. Findings from interviews with 16 key informants from government, partner organizations, and international health agencies fit within the following four overarching themes: (1) population-level vulnerabilities to pneumonia, exacerbated by climatic risks and low levels of maternal education; (2) disease burden and the interest in enhancing surveillance to monitor vaccine impact and integrate disease control efforts; (3) policy processes, including formalizing vaccine decision-making; and (4) vaccine implementation preparation, including the conduct of robust communication campaigns, training, and cold chain upgrades. This research explores perspectives from leaders in these countries which are at pivotal moments in their journeys toward introducing PCV. Widespread commitment among leaders, in addition to financial support, will facilitate vaccine introduction. Further, fostering a shared understanding among partners about context-specific determinants of program success will help build tailored implementation strategies for each country.

Neutralizing monoclonal antibodies protect against human adenovirus type 55 infection in transgenic mice and tree shrews

Re-emerging human adenovirus type 55 (HAdV55) has become a significant threat to public health due to its widespread circulation and the association with severe pneumonia, but an effective anti-HAdV55 agent remains unavailable. Herein, we report the generation of macaque-derived, human-like monoclonal antibodies (mAbs) protecting against HAdV55 infection with high potency. Using fluorophore-labelled HAdV55 virions as probes, we isolated specific memory B cells from rhesus macaques (Macaca mulatta) that were immunized twice with an experimental vaccine based on E1-, E3-deleted, replication-incompetent HAdV55. We cloned a total of 19 neutralizing mAbs, nine of which showed half-maximal inhibitory concentrations below 1.0 ng/ml. These mAbs recognized the hyper-variable-region (HVR) 1, 2, or 7 of viral hexon protein, or the fibre knob. In transgenic mice expressing human desmoglein-2, the major cellular receptor for HAdV55, a single intraperitoneal injection with hexon-targeting mAbs efficiently prevented HAdV55 infection, and mAb 29C12 showed protection at a dose as low as 0.004 mg/kg. Fibre-targeting mAb 28E8, however, showed protection only at a dose up to 12.5 mg/kg. In tree shrews that are permissive for HAdV55 infection and disease, mAb 29C12 effectively prevented HAdV55-caused pneumonia. Further analysis revealed that fibre-targeting mAbs blocked the attachment of HAdV55 to host cells, whereas hexon-targeting mAbs, regardless of their targeting HVRs, mainly functioned at post-attachment stage via inhibiting viral endosomal escape. Our results indicate that hexon-targeting mAbs have great anti-HAdV55 activities and warrant pre-clinical and clinical evaluation.

The role of HDAC6 in enhancing macrophage autophagy via the autophagolysosomal pathway to alleviate legionella pneumophila-induced pneumonia

Legionella pneumophila (L. pneumophila) is a prevalent pathogenic bacterium responsible for significant global health concerns. Nonetheless, the precise pathogenic mechanisms of L. pneumophila have still remained elusive. Autophagy, a direct cellular response to L. pneumophila infection and other pathogens, involves the recognition and degradation of these invaders in lysosomes. Histone deacetylase 6 (HDAC6), a distinctive member of the histone deacetylase family, plays a multifaceted role in autophagy regulation. This study aimed to investigate the role of HDAC6 in macrophage autophagy via the autophagolysosomal pathway, leading to alleviate L. pneumophila-induced pneumonia. The results revealed a substantial upregulation of HDAC6 expression level in murine lung tissues infected by L. pneumophila. Notably, mice lacking HDAC6 exhibited a protective response against L. pneumophila-induced pulmonary tissue inflammation, which was characterized by the reduced bacterial load and diminished release of pro-inflammatory cytokines. Transcriptomic analysis has shed light on the regulatory role of HDAC6 in L. pneumophila infection in mice, particularly through the autophagy pathway of macrophages. Validation using L. pneumophila-induced macrophages from mice with HDAC6 gene knockout demonstrated a decrease in cellular bacterial load, activation of the autophagolysosomal pathway, and enhancement of cellular autophagic flux. In summary, the findings indicated that HDAC6 knockout could lead to the upregulation of p-ULK1 expression level, promoting the autophagy-lysosomal pathway, increasing autophagic flux, and ultimately strengthening the bactericidal capacity of macrophages. This contributes to the alleviation of L. pneumophila-induced pneumonia.

Comparative Efficacy of Budesonide/Formoterol Versus Fluticasone/Salmeterol in Patients With Moderate-to-Severe Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis

BACKGROUND/OBJECTIVE

To compare the efficacy of budesonide/formoterol (BF) versus fluticasone/salmeterol (FS) in patients with moderate-to-severe chronic obstructive pulmonary disease (COPD).

METHODS

The PubMed, Embase, Cochrane Library, and Web of Science databases were searched for studies comparing BF versus FS in the treatment of COPD from inception to July 17, 2023. Outcomes, including exacerbations, hospitalizations, pneumonia, emergency department (ED) visits for COPD, length of hospitalization, and number of exacerbations, were compared using risk ratio (RR) with corresponding 95% confidence interval (CI) or weighted mean difference (WMD) with 95% CI. All statistical analyses were performed using Stata version 12.0.

RESULTS

Ten studies comprising a total of 136,369 participants were included. Compared with those treated with FS, patients with COPD treated with BF experienced a reduced number of exacerbations (RR 0.91 [95% CI 0.83-1.00]; p = 0.040), hospitalizations (RR 0.77 [95% CI 0.67-0.88]; p < 0.001), and frequency of pneumonia (RR 0.77 [95% CI 0.64-0.92]; p = 0.05). However, no significant difference was observed between BF and FS in terms of ED visits for COPD (RR 0.87 [95% CI 0.69-1.10]; p = 0.243), length of hospitalization (WMD -0.18 [95% CI -0.62-0.27]; p = 0.437), and number of exacerbations (WMD -0.06 [95% CI -0.28-0.16]; p = 0.602). Notably, no significant heterogeneity was noted in length of hospitalization between the two groups, whereas clear heterogeneity was observed in other outcomes (I2 > 50%, p < 0.05).

CONCLUSION

Compared with FS, BF therapy appears to be a more promising treatment strategy for patients with moderate-to-severe COPD; however, this should be verified in further high-quality studies.

Real-World Effectiveness of Single-Inhaler Triple Therapy for COPD: Impact of Diabetes Comorbidity

Type 2 diabetes is a frequent comorbidity in chronic obstructive pulmonary disease (COPD) patients, with the GOLD treatment recommendations asserting that the presence of diabetes be disregarded in the choice of treatment.

In a cohort of COPD patients with frequent exacerbations, initiators of single-inhaler triple therapy or dual bronchodilators were compared on the incidence of COPD exacerbation and pneumonia over one year, adjusted by propensity score weighting and stratified by type 2 diabetes.

The COPD cohort included 1,114 initiators of triple inhalers and 4,233 of dual bronchodilators (28% with type 2 diabetes). The adjusted hazard ratio (HR) of exacerbation with triple therapy was 1.04 (95% CI: 0.86-1.25) among COPD patients with type 2 diabetes and 0.74 (0.65-0.85) in those without. The incidence of severe pneumonia was elevated with triple therapy among patients with type 2 diabetes (HR 1.77; 1.14-2.75).

Triple therapy in COPD is effective among those without, but not those with, type 2 diabetes. Future therapeutic trials in COPD should consider diabetes comorbidity.

Rhinovirus infection and co-infection in children with severe acute respiratory infection during the COVID-19 pandemic period

Rhinovirus causes respiratory tract infections in children and is found in co-infections. The objective of this research was to study the clinical profile of rhinovirus infection and co-infection in children with severe acute respiratory infection (SARI) during the COVID-19 pandemic period. We included 606 children ranging in age from 0.1 to 144 months of age from March 2020 to December 2021, hospitalized in the Pediatric Intensive Care Unit (PICU). The samples were collected by secretion from the nasopharynx region. A total of 259 children were tested positive for viral infection, 153 (59.07%) of them had a single rhinovirus infection and, 56 (36.6%) were aged between 60.1 and 144 months. Nine types of co-infections were identified and were found coinfection with three or more viruses (22/104, 21.15%). Observing the seasonality, the number of cases was similar between 2020 (49.53%) and 2021 (51.47%). Patients with a single infection (86.88%) and coinfection (67.30%) were more likely to have coughed. Patients with co-infection required the use of O2 for longer than those with a single rhinovirus infection. Hemogram results obtained from individuals with a single infection had higher levels of urea when compared to patients with co-infection with and other respiratory viruses. Multiple correspondence analyses indicated different clinical symptoms and comorbidities in patients with co-infection compared to those with single infection. The results found that the rhinovirus was much prevalent virus during the pandemic period and was found in co-infection with other virus types, what is important to diagnostic for the correct treatment of patients.

IL-4 regulates neutrophilic pulmonary inflammation in a mouse model of bronchial asthma

Neutrophilic pulmonary inflammation in asthmatics substantially exacerbates the severity of the disease leading to resistance to conventional corticosteroid therapy. Many studies established the involvement of Th1- and Th17-cells and cytokines produced by them (IFNg, IL-17A, IL-17F etc.) in neutrophilic pulmonary inflammation. Recent studies revealed that IL-4 - a Th2-cytokine regulates neutrophil effector functions and migration. It was showed that IL-4 substantially reduces neutrophilic inflammation of the skin in a mouse model of cutaneous bacterial infection and blood neutrophilia in a mouse model systemic bacterial infection. However, there are no data available regarding the influence of IL-4 on non-infectious pulmonary inflammation. In the current study we investigated the effects of IL-4 in a previously developed mouse model of neutrophilic bronchial asthma. We showed that systemic administration of IL-4 significantly restricts neutrophilic inflammation of the respiratory tract probably through the suppression of Th1-/Th17-immune responses and downregulation of CXCR2. Additionally, pulmonary neutrophilic inflammation could be alleviated by IL-4-dependant polarization of N2 neutrophils and M2 macrophages, expressing anti-inflammatory TGFβ. Considering these, IL-4 might be used for reduction of exaggerated pulmonary neutrophilic inflammation and overcoming corticosteroid insensitivity of asthma patients.

Different ventilation intensities among various categories of patients ventilated for reasons other than ARDS--A pooled analysis of 4 observational studies

PURPOSE

We investigated driving pressure (ΔP) and mechanical power (MP) and associations with clinical outcomes in critically ill patients ventilated for reasons other than ARDS.

MATERIALS AND METHODS

Individual patient data analysis of a pooled database that included patients from four observational studies of ventilation. ΔP and MP were compared among invasively ventilated non-ARDS patients with sepsis, with pneumonia, and not having sepsis or pneumonia. The primary endpoint was ΔP; secondary endpoints included MP, ICU mortality and length of stay, and duration of ventilation.

RESULTS

This analysis included 372 (11%) sepsis patients, 944 (28%) pneumonia patients, and 2040 (61%) patients ventilated for any other reason. On day 1, median ΔP was higher in sepsis (14 [11-18] cmH2O) and pneumonia patients (14 [11-18]cmH2O), as compared to patients not having sepsis or pneumonia (13 [10-16] cmH2O) (P < 0.001). Median MP was also higher in sepsis and pneumonia patients. ΔP, as opposed to MP, was associated with ICU mortality in sepsis and pneumonia patients.

CONCLUSIONS

The intensity of ventilation differed between patients with sepsis or pneumonia and patients receiving ventilation for any other reason; ΔP was associated with higher mortality in sepsis and pneumonia patients.

REGISTRATION

This post hoc analysis was not registered; the individual studies that were merged into the used database were registered at clinicaltrials.gov: NCT01268410 (ERICC), NCT02010073 (LUNG SAFE), NCT01868321 (PRoVENT), and NCT03188770 (PRoVENT-iMiC).

Prediction of acute lung injury assessed by chest computed tomography, oxygen saturation/fraction of inspired oxygen ratio, and serum lactate dehydrogenase in patients with COVID-19

INTRODUCTION

In treating acute hypoxemic respiratory failure (AHRF) caused by coronavirus disease 2019 (COVID-19), clinicians choose respiratory therapies such as low-flow nasal cannula oxygenation, high-flow nasal cannula oxygenation, or mechanical ventilation after assessment of the patient's condition. Chest computed tomography (CT) imaging contributes significantly to diagnosing COVID-19 pneumonia. However, the costs and potential harm to patients from radiation exposure need to be considered. This study was performed to predict the quantitative extent of COVID-19 acute lung injury using clinical indicators such as an oxygenation index and blood test results.

METHODS

We analyzed data from 192 patients with COVID-19 AHRF. Multiple logistic regression was used to determine correlations between the lung infiltration volume (LIV) and other pathophysiological or biochemical laboratory parameters.

RESULTS

Among 13 clinical parameters, we identified the oxygen saturation/fraction of inspired oxygen ratio (SF ratio) and serum lactate dehydrogenase (LD) concentration as factors associated with the LIV. In the binary classification of an LIV of ≥20 % or not and with the borderline LD = 2.2 × [SF ratio]-182.4, the accuracy, precision, diagnostic odds ratio, and area under the summary receiver operating characteristic curve were 0.828, 0.818, 23.400, and 0.870, respectively.

CONCLUSIONS

These data suggest that acute lung injury due to COVID-19 pneumonia can be estimated using the SF ratio and LD concentration without a CT scan. These findings may provide significant clinical benefit by allowing clinicians to predict acute lung injury levels using simple, minimally invasive assessment of oxygenation capacity and biochemical blood tests.

Pla2g5 contributes to viral-like-induced lung inflammation through macrophage proliferation and LA/Ffar1 lung cell recruitment

Macrophages expressing group V phospholipase A2 (Pla2g5) release the free fatty acid (FFA) linoleic acid (LA), potentiating lung type 2 inflammation. Although Pla2g5 and LA increase in viral infections, their role remains obscure. We generated Pla2g5flox/flox mice, deleted Pla2g5 by using the Cx3cr1cre transgene, and activated bone marrow-derived macrophages (BM-Macs) with poly:IC, a synthetic double-stranded RNA that triggers a viral-like immune response, known Pla2g5-dependent stimuli (IL-4, LPS + IFNγ, IL-33 + IL-4 + GM-CSF) and poly:IC + LA followed by lipidomic and transcriptomic analysis. Poly:IC-activated Pla2g5flox/flox;Cx3cr1cre/+ BM-Macs had downregulation of major bioactive lipids and critical enzymes producing those bioactive lipids. In addition, AKT phosphorylation was lower in poly:IC-stimulated Pla2g5flox/flox;Cx3cr1cre/+ BM-Macs, which was not restored by adding LA to poly:IC-stimulated BM-Macs. Consistently, Pla2g5flox/flox;Cx3cr1cre/+ mice had diminished poly:IC-induced lung inflammation, including inflammatory macrophage proliferation, while challenging Pla2g5flox/flox;Cx3cr1cre/+ mice with poly:IC + LA partially restored lung inflammation and inflammatory macrophage proliferation. Finally, mice lacking FFA receptor-1 (Ffar1)-null mice had reduced poly:IC-induced lung cell recruitment and tissue macrophage proliferation, not corrected by LA. Thus, Pla2g5 contributes to poly:IC-induced lung inflammation by regulating inflammatory macrophage proliferation and LA/Ffar1-mediated lung cell recruitment and tissue macrophage proliferation.

Fatal attractions that trigger inflammation and drive atherosclerotic disease

BACKGROUND

Atherosclerosis is the salient, underlying cause of cardiovascular diseases, such as arrhythmia, coronary artery disease, cardiomyopathy, pulmonary embolism and myocardial infarction. In recent years, atherosclerosis pathophysiology has evolved from a lipid-based to an inflammation-centric ideology.

METHODS

This narrative review is comprised of review and original articles that were found through the PubMed search engine. The following search terms or amalgamation of terms were used: "cardiovascular disease," "atherosclerosis," "inflammation," "GRP78," "Hsp60," "oxidative low-density lipoproteins," "aldehyde dehydrogenase," "β2-glycoprotein," "lipoprotein lipase A," "human cytomegalovirus." "SARS-CoV-2," "chlamydia pneumonia," "autophagy," "thrombosis" and "therapeutics."

RESULTS

Emerging evidence supports the concept that atherosclerosis is associated with the interaction between cell surface expression of stress response chaperones, including GRP78 and Hsp60, and their respective autoantibodies. Moreover, various other autoantigens and their autoantibodies have displayed a compelling connection with the development of atherosclerosis, including oxidative low-density lipoproteins, aldehyde dehydrogenase, β2-glycoprotein and lipoprotein lipase A. Atherosclerosis progression is also concurrent with viral and bacterial activators of various diseases. This narrative review will focus on the contributions of human cytomegalovirus as well as SARS-CoV-2 and chlamydia pneumonia in atherosclerosis development. Notably, the interaction of an autoantigen with their respective autoantibodies or the presence of a foreign antigen can enhance inflammation development, which leads to atherosclerotic lesion progression.

CONCLUSION

We will highlight and discuss the complex role of the interaction between autoantigens and autoantibodies, and the presence of foreign antigens in the development of atherosclerotic lesions in relationship to pro-inflammatory responses.

Utilizing Deep Learning and Computed Tomography to Determine Pulmonary Nodule Activity in Patients With Nontuberculous Mycobacterial-Lung Disease

PURPOSE

To develop and evaluate a deep convolutional neural network (DCNN) model for the classification of acute and chronic lung nodules from nontuberculous mycobacterial-lung disease (NTM-LD) on computed tomography (CT).

MATERIALS AND METHODS

We collected a data set of 650 nodules (316 acute and 334 chronic) from the CT scans of 110 patients with NTM-LD. The data set was divided into training, validation, and test sets in a ratio of 4:1:1. Bounding boxes were used to crop the 2D CT images down to the area of interest. A DCNN model was built using 11 convolutional layers and trained on these images. The performance of the model was evaluated on the hold-out test set and compared with that of 3 radiologists who independently reviewed the images.

RESULTS

The DCNN model achieved an area under the receiver operating characteristic curve of 0.806 for differentiating acute and chronic NTM-LD nodules, corresponding to sensitivity, specificity, and accuracy of 76%, 68%, and 72%, respectively. The performance of the model was comparable to that of the 3 radiologists, who had area under the receiver operating characteristic curve, sensitivity, specificity, and accuracy of 0.693 to 0.771, 61% to 82%, 59% to 73%, and 60% to 73%, respectively.

CONCLUSIONS

This study demonstrated the feasibility of using a DCNN model for the classification of the activity of NTM-LD nodules on chest CT. The model performance was comparable to that of radiologists. This approach can potentially and efficiently improve the diagnosis and management of NTM-LD.

Diagnostic testing and antibiotic utilization among inpatients evaluated for coronavirus disease 2019 (COVID-19) pneumonia

We evaluated diagnostic test and antibiotic utilization among 252 patients from 11 US hospitals who were evaluated for coronavirus disease 2019 (COVID-19) pneumonia during the severe acute respiratory coronavirus virus 2 (SARS-CoV-2) omicron variant pandemic wave. In our cohort, antibiotic use remained high (62%) among SARS-CoV-2-positive patients and even higher among those who underwent procalcitonin testing (68%).

Clinical features and risk factors of primary Sjögren's syndrome complicated with severe pneumonia: a case-control study

OBJECTIVES

To analyze clinical characteristics, risk factors, pathogen distribution, and prognostic markers in primary Sjögren's syndrome (pSS) patients with severe pneumonia (SP) compared to those without severe pneumonia (NSP).

METHODS

This case-control study included 24 hospitalized pSS patients with SP and 96 NSP at the first affiliated hospital of Soochow university from June 2014 to May 2023. Data encompassing demographics, comorbidities, treatments, and laboratory results were retrospectively collected. Univariate and multivariate regression analyses, ROC curves, and statistical analyses using SPSS 23.0 assessed risk factors. The study retrospectively analyzed clinical features and risk factors, highlighting distinct parameters between pSS patients with and without SP.

RESULTS

Marked differences were observed in several parameters: pSS activity(P < 0.001), white blood cell (P = 0.043), lymphocyte (P < 0.001), neutrophils (P = 0.042), C-reactive protein (P = 0.042), and CD8+ T cell (P = 0.017). Notably, lymphocyte count and SS activity demonstrated robust discrimination ability (AUC > 0.85). C-reactive protein (CRP), procalcitonin, CD4+ T cell, and IgA showed significant associations with SP; higher CRP levels correlated with increased risk, while lower CD4+ T cell and IgA levels associated with increased risk. SS activity significantly impacted outcomes. Various biomarkers exhibited diverse discriminatory abilities but lacked strong predictive associations with outcomes.

CONCLUSION

pSS patients with SP exhibited higher disease activity and altered immune profiles compared to those NSP. Lymphocyte count and SS activity emerged as robust discriminators. Higher CRP levels correlated with increased risk of SP, while lower CD4+T cell and IgA levels associated with increased risk. SS activity significantly impacted patient outcomes. Key Points • pSS patients with SP exhibited higher disease activity and altered immune profiles compared to those NSP. • Lymphocyte count and SS activity emerged as robust discriminators. • Higher CRP levels correlated with increased risk of SP, while lower CD4+ T cell and IgA levels associated with decreased risk. • SS activity significantly impacted patient outcomes.

Physiologic parameters and radiologic findings can predict pulmonary complications and guide management in traumatic rib fractures

BACKGROUND

Traumatic rib fracture is associated with a high morbidity rate and identifying patients at risk of developing pulmonary complications (PC) can guide management and potentially decrease unnecessary intensive care admissions. Therefore, we sought to assess and compare the utility of a physiologic parameter, vital capacity (VC), with the admission radiologic findings (RibScore) in predicting PC in patients with rib fractures.

METHODS

This is a single-center retrospective review (2015-2018) of all adult (≥18 years) patients admitted to a Level I trauma center with traumatic rib fracture. Exclusion criteria included no CT scan and absence of VC within 48 h of admission. The cohort was stratified into two groups based on presence or absence of PC (pneumonia, unplanned intubation, unplanned transfer to the intensive care unit for a respiratory concern, or the need for a tracheostomy). Multivariable logistic regression models were constructed to identify predictors of PC.

RESULTS

A total of 654 patients met the inclusion criteria of whom 70 % were males. The median age was 51 years and fall (48 %) was the most common type of injury. A total of 36 patients (5.5 %) developed a pulmonary complication. These patients were more likely to be older, had a higher ISS, and were more likely to require a tube thoracostomy placement. On multivariable logistic regression, first VC ≤30 % (AOR: 4.29), day 1 VC ≤30 % (AOR: 3.61), day 2 VC ≤30 % (AOR: 5.54), Δ(Day2-Day1 VC) (AOR: 0.96), and RibScore ≥2 (AOR: 3.19) were significantly associated with PC. On discrimination analysis, day 2 VC had the highest area under the receiver operating characteristic curve (AuROC), 0.81, and was superior to first VC and day 1 VC in predicting PC. There was no statistically significant difference in predicting PC between day 2 VC and RibScore. On multivariable analysis, first VC ≤30 %, day 1 VC ≤30 %, day 2 VC ≤30 %, and admission RibScore ≥2 were associated with prolonged hospital and ICU LOS.

CONCLUSION

VC and RibScore emerged as independent predictors of PC. However, VC was not found to be superior to RibScore in predicting PC. Further prospective research is warranted to validate the findings of this study.

Incidence, etiology, and outcome of hospital-acquired pneumonia in patients with acute exacerbation of fibrotic idiopathic interstitial pneumonia

BACKGROUND

Acute exacerbations (AEs) of fibrotic idiopathic interstitial pneumonia (fIIP) that require hospitalization occur in some patients. During hospitalization, these patients can develop hospital-acquired pneumonia (HAP), a common hospital-acquired infection with a high mortality rate. However, the characteristics of HAP in AE-fIIP remain unknown. The purpose of this study was to determine the incidence, causative pathogens, and outcomes of HAP in patients with AE-fIIP.

METHODS

The medical records of consecutive patients who were hospitalized with AE-fIIP from January 2008 to December 2019 were analyzed for the incidence, causative pathogen, and survival of HAP. The records of patients with an obvious infection-triggered AE were excluded from analysis.

RESULTS

There were 128 patients with AE-fIIP (89 with idiopathic pulmonary fibrosis [IPF] and 39 with non-IPF fIIP) who were hospitalized a total of 155 times (111 with IPF and 44 with non-IPF fIIP). HAP occurred in 49 patients (40 with IPF and 9 with non-IPF fIIP). The incidence and the in-hospital mortality rates of HAP in patients with AE-fIIP were high, at 32.2% and 48.9%, respectively. Corynebacterium spp. was the most common causative pathogen, which was followed by human cytomegalovirus (HCMV).

CONCLUSIONS

The incidence and the in-hospital mortality rates of HAP in patients with AE-fIIP are high. To improve their survival, patients with fIIP who had AEs and HAP should receive prompt empirical treatment for possible infections with Corynebacterium spp. and testing for HCMV.

Levofloxacin loaded chitosan and poly-lactic-co-glycolic acid nano-particles against resistant bacteria: Synthesis, characterization and antibacterial activity

BACKGROUND

With the global increase in antibacterial resistance, the challenge faced by developing countries is to utilize the available antibiotics, alone or in combination, against resistant bacterial strains. We aimed to encapsulate the levofloxacin (LVX) into polymeric nanoparticles using biodegradable polymers i.e. Chitosan and PLGA, estimating their physicochemical characteristics followed by functional assessment as nanocarriers of levofloxacin against the different resistant strains of bacteria isolated from biological samples collected from tertiary care hospital in Lahore, Pakistan.

METHODS

LVX-NPs were synthesized using ion gelation and double emulsion solvent-evaporation method employing chitosan (CS) and poly-lactic-co-glycolic acid (PLGA), characterized via FTIR, XRD, SEM, and invitro drug release studies, while antibacterial activity was assessed using Kirby-Bauer disc-diffusion method.

RESULTS

Data revealed that the levofloxacin-loaded chitosan nanoparticles showed entrapment efficiency of 57.14% ± 0.03 (CS-I), 77.30% ± 0.08(CS-II) and 87.47% ± 0.08 (CS-III). The drug content, particle size, and polydispersity index of CS-I were 52.22% ± 0.2, 559 nm ± 31 nm, and 0.030, respectively, whereas it was 66.86% ± 0.17, 595 nm ± 52.3 nm and 0.057, respectively for CS-II and 82.65% ± 0.36, 758 nm ± 24 nm and 0.1, respectively for CS-III. The PLGA-levofloxacin nanoparticles showed an entrapment efficiency of 42.80% ± 0.4 (PLGA I) and 23.80% ± 0.4 (PLGA II). The drug content, particle size and polydispersity index of PLGA-I were 86% ± 0.21, 92 nm ± 10 nm, and 0.058, respectively, whereas it was 52.41% ± 0.45, 313 nm ± 32 nm and 0.076, respectively for PLGA-II. The XRD patterns of both polymeric nanoparticles showed an amorphous nature. SEM analysis reflects the circular-shaped agglomerated nanoparticles with PLGA polymer and dense spherical nanoparticles with chitosan polymer. The in-vitro release profile of PLGA-I nanoparticles showed a sustained release of 82% in 120 h and it was 58.40% for CS-III. Both types of polymeric nanoparticles were found to be stable for up to 6 months without losing any major drug content. Among the selected formulations, CS-III and PLGA-I, CS-III had better antibacterial potency against gram+ve and gram-ve bacteria, except for K. pneumonia, yet, PLGA-I demonstrated efficacy against K. pneumonia as per CSLI guidelines. All formulations did not exhibit any signs of hemotoxicity, nonetheless, the CS-NPs tend to bind on the surface of RBCs.

CONCLUSION

These data suggested that available antibiotics can effectively be utilized as nano-antibiotics against resistant bacterial strains, causing severe infections, for improved antibiotic sensitivity without compromising patient safety.

Spontaneous regression of acute fibrinous organizing pneumonia induced by COVID-19 vaccination: A case report

A 42-year-old woman visited our hospital with complaints of fever, muscle pain, and dyspnea one week after receiving the coronavirus disease 2019 (COVID-19) vaccine. Chest high-resolution computed tomography showed a patchy consolidation and ground-glass attenuation in the both lungs, consistent with acute interstitial pneumonia. Transbronchial lung cryobiopsy revealed organizing pneumonia with marked intra-alveolar fibrin, and pathologically diagnosed as acute fibrinous organizing pneumonia (AFOP). Other causative diseases such as dermatomyositis was clinically ruled out, and COVID-19 vaccine-induced AFOP was diagnosed. Physician should check the history of COVID-19 vaccination when encountering a case of AFOP with an unknown cause.

Pulmonary infections in the returning traveler

PURPOSE OF REVIEW

The recent COVID-19 pandemic has shaped the epidemiology of other infectious diseases globally. International tourist arrivals are increasing and recovering to prepandemic levels. This review focuses on respiratory infections in travelers, highlighting the characteristics of the main imported viral, bacterial, fungal, and parasitic infections with pulmonary involvement.

RECENT FINDINGS

A recent systematic review estimated a prevalence of respiratory symptoms in travelers of around 35%, increasing to nearly 65% in the context of mass gatherings. Common viral and bacterial pathogens account for the majority of respiratory infections with an identified cause; however, recent data focus on the need for surveillance of emerging infections such as MERS-CoV, henipaviruses and multidrug resistant bacteria, which may be spread through travel. Fungal and parasitic respiratory infections are less common, and acquisition is usually associated with specific risk factors or exposure in endemic areas. Special risk groups, such as immunocompromised travelers, may be particularly vulnerable, presenting with severe disease or reactivation of latent infections.

SUMMARY

The next significant international epidemic could involve another new infectious agent causing respiratory disease and spreading via mobile populations. Official protocols should be adhered to, and public health interventions implemented for effective control. Continued and globally coordinated investments in research for new vaccines, therapeutic agents, disease modeling, and digital tracking strategies are essential.

CD-Net: Cascaded 3D Dilated convolutional neural network for pneumonia lesion segmentation

COVID-19 is a global pandemic that has caused significant global, social, and economic disruption. To effectively assist in screening and monitoring diagnosed cases, it is crucial to accurately segment lesions from Computer Tomography (CT) scans. Due to the lack of labeled data and the presence of redundant parameters in 3D CT, there are still significant challenges in diagnosing COVID-19 in related fields. To address the problem, we have developed a new model called the Cascaded 3D Dilated convolutional neural network (CD-Net) for directly processing CT volume data. To reduce memory consumption when cutting volume data into small patches, we initially design a cascade architecture in CD-Net to preserve global information. Then, we construct a Multi-scale Parallel Dilated Convolution (MPDC) block to aggregate features of different sizes and simultaneously reduce the parameters. Moreover, to alleviate the shortage of labeled data, we employ classical transfer learning, which requires only a small amount of data while achieving better performance. Experimental results conducted on the different public-available datasets verify that the proposed CD-Net has reduced the negative-positive ratio and outperformed other existing segmentation methods while requiring less data.

Retrospective study on the health and economic burden of hospitalized patients due to pneumonia and invasive pneumococcal infections in Belgium settings

INTRODUCTION

pneumococcal infections are associated with high morbidity, hospitalisation and mortality. The objective of this study was to investigate the health and economic burden of all-cause pneumonia and invasive pneumococcal disease in Belgian hospital settings, by patient's age and risk profile.

METHODS

This descriptive retrospective study was conducted in 17 Belgian hospitals. Univariate and multivariate logistic linear regression models were performed. The Health Insurance and patient's cost perspectives were considered because a few studies report these costs.

RESULTS

The analysis has included 4,712 hospital admissions over the year 2018. Median hospitalization costs were higher for invasive pneumococcal infection diagnosis than for all-cause pneumonia (p < 0,001), respectively 4,051€ and 3,362€. Other factors associated with higher hospitalization cost were patient's high-risk profile, admission to emergency unit, transfer from nursing home, admission to intensive care unit and length of stay.

CONCLUSION

Streptococcus pneumoniae infections remain a public health problem with significant cost for the Health Insurance and poor prognosis. Invasive pneumococcal infections are associated with longer hospital stays and required more intensive care than all other causes of pneumonia, in addition to be more costly, which justifies more attention for vaccination. This study also suggests an increase of economic and health burden with age and presence of underlying conditions.

Multiparameter immunoprofiling for the diagnosis and differentiation of progressive versus nonprogressive nontuberculous mycobacterial lung disease-A pilot study

Clinical prediction of nontuberculous mycobacteria lung disease (NTM-LD) progression remains challenging. We aimed to evaluate antigen-specific immunoprofiling utilizing flow cytometry (FC) of activation-induced markers (AIM) and IFN-γ enzyme-linked immune absorbent spot assay (ELISpot) accurately identifies patients with NTM-LD, and differentiate those with progressive from nonprogressive NTM-LD. A Prospective, single-center, and laboratory technician-blinded pilot study was conducted to evaluate the FC and ELISpot based immunoprofiling in patients with NTM-LD (n = 18) and controls (n = 22). Among 18 NTM-LD patients, 10 NTM-LD patients were classified into nonprogressive, and 8 as progressive NTM-LD based on clinical and radiological features. Peripheral blood mononuclear cells were collected from patients with NTM-LD and control subjects with negative QuantiFERON results. After stimulation with purified protein derivative (PPD), mycobacteria-specific peptide pools (MTB300, RD1-peptides), and control antigens, we performed IFN-γ ELISpot and FC AIM assays to access their diagnostic accuracies by receiver operating curve (ROC) analysis across study groups. Patients with NTM-LD had significantly higher percentage of CD4+/CD8+ T-cells co-expressing CD25+CD134+ in response to PPD stimulation, differentiating between NTM-LD and controls. Among patients with NTM-LD, there was a significant difference in CD25+CD134+ co-expression in MTB300-stimulated CD8+ T-cells (p <0.05; AUC-ROC = 0.831; Sensitivity = 75% [95% CI: 34.9-96.8]; Specificity = 90% [95% CI: 55.5-99.7]) between progressors and nonprogressors. Significant differences in the ratios of antigen-specific IFN-γ ELISpot responses were also seen for RD1-nil/PPD-nil and RD1-nil/anti-CD3-nil between patients with nonprogressive vs. progressive NTM-LD. Our results suggest that multiparameter immunoprofiling can accurately identify patients with NTM-LD and may identify patients at risk of disease progression. A larger longitudinal study is needed to further evaluate this novel immunoprofiling approach.

Incidence of pneumococcal disease in children ≤48 months old in the United States: 1998-2019

BACKGROUND

Pneumococcal disease (PD) is a major cause of morbidity and mortality among children, particularly in the youngest age groups. This study aimed to assess the incidence of PD over time by age group in young children with commercial or Medicaid coverage in the US.

METHODS

Episodes of invasive pneumococcal disease (IPD), all-cause pneumonia (ACP), and acute otitis media (AOM) were identified in the MarketScan® Commercial and Medicaid claims databases using diagnosis codes among children aged ≤ 48 months with confirmed date of birth (DoB), at any time during the study period (1998-2019). DoB was assigned using diagnosis codes for birth or delivery using the child's or mother's medical claims to ensure accurate age determination. Annual incidence rates (IRs) were calculated as number of disease episodes/100,000 person-years (PY) for IPD and ACP and episodes/1,000 PY for AOM, for children aged 0-6, 7-12, 12-24, and 25-48 months.

RESULTS

Annual IPD IRs declined from 53 to 7 episodes/100,000 PY between 1998 and 2019 in commercially-insured and 58 to 9 episodes/100,000 PY between 2001 and 2019 in Medicaid-insured children. Annual ACP IRs declined from 5,600 to 3,952 episodes/100,000 PY, and from 6,706 to 4,521 episodes/100,000 PY, respectively, over these periods. In both populations, children aged 0-6 months had the highest incidence of IPD and inpatient ACP. Annual AOM IRs declined from 1,177 to 738 episodes/1,000 PY (commercially-insured) and 633 to 624 episodes/1,000 PY (Medicaid-insured), over these periods. IRs were higher in rural vs. urban areas for all disease manifestations.

CONCLUSIONS

Incidence rates of IPD, ACP, and AOM decreased in children with commercial insurance and Medicaid coverage from 1998 to 2019. However, burden of disease remained substantial, with higher annual IRs for IPD and ACP for Medicaid-insured vs. commercially-insured children. IPD and inpatient ACP were most common in the youngest children 0-6 months old, followed by the 7-12-month age group.

Combining quantitative and qualitative analysis for scoring pleural line in lung ultrasound

Objective.Accurate assessment of pleural line is crucial for the application of lung ultrasound (LUS) in monitoring lung diseases, thereby aim of this study is to develop a quantitative and qualitative analysis method for pleural line.Approach.The novel cascaded deep learning model based on convolution and multilayer perceptron was proposed to locate and segment the pleural line in LUS images, whose results were applied for quantitative analysis of textural and morphological features, respectively. By using gray-level co-occurrence matrix and self-designed statistical methods, eight textural and three morphological features were generated to characterize the pleural lines. Furthermore, the machine learning-based classifiers were employed to qualitatively evaluate the lesion degree of pleural line in LUS images.Main results.We prospectively evaluated 3770 LUS images acquired from 31 pneumonia patients. Experimental results demonstrated that the proposed pleural line extraction and evaluation methods all have good performance, with dice and accuracy of 0.87 and 94.47%, respectively, and the comparison with previous methods found statistical significance (P< 0.001 for all). Meanwhile, the generalization verification proved the feasibility of the proposed method in multiple data scenarios.Significance.The proposed method has great application potential for assessment of pleural line in LUS images and aiding lung disease diagnosis and treatment.

Antimicrobial resistance prediction by clinical metagenomics in pediatric severe pneumonia patients

BACKGROUND

Antimicrobial resistance (AMR) is a major threat to children's health, particularly in respiratory infections. Accurate identification of pathogens and AMR is crucial for targeted antibiotic treatment. Metagenomic next-generation sequencing (mNGS) shows promise in directly detecting microorganisms and resistance genes in clinical samples. However, the accuracy of AMR prediction through mNGS testing needs further investigation for practical clinical decision-making.

METHODS

We aimed to evaluate the performance of mNGS in predicting AMR for severe pneumonia in pediatric patients. We conducted a retrospective analysis at a tertiary hospital from May 2022 to May 2023. Simultaneous mNGS and culture were performed on bronchoalveolar lavage fluid samples obtained from pediatric patients with severe pneumonia. By comparing the results of mNGS detection of microorganisms and antibiotic resistance genes with those of culture, sensitivity, specificity, positive predictive value, and negative predictive value were calculated.

RESULTS

mNGS detected bacterial in 71.7% cases (86/120), significantly higher than culture (58/120, 48.3%). Compared to culture, mNGS demonstrated a sensitivity of 96.6% and a specificity of 51.6% in detecting pathogenic microorganisms. Phenotypic susceptibility testing (PST) of 19 antibiotics revealed significant variations in antibiotics resistance rates among different bacteria. Sensitivity prediction of mNGS for carbapenem resistance was higher than penicillins and cephalosporin (67.74% vs. 28.57%, 46.15%), while specificity showed no significant difference (85.71%, 75.00%, 75.00%). mNGS also showed a high sensitivity of 94.74% in predicting carbapenem resistance in Acinetobacter baumannii.

CONCLUSIONS

mNGS exhibits variable predictive performance among different pathogens and antibiotics, indicating its potential as a supplementary tool to conventional PST. However, mNGS currently cannot replace conventional PST.

Polydopamine-based nano adjuvant as a promising vaccine carrier induces significant immune responses against Acinetobacter baumannii-associated pneumonia

The objective of this study was to assess the effectiveness of polydopamine nanoparticles (PDANPs) as a delivery system for intranasal antigen administration to prevent Acinetobacter baumannii (A. baumannii)-associated pneumonia. In the in vitro phase, the conserved outer membrane protein 22 (Omp22)-encoding gene of A. baumannii was cloned, expressed, and purified, resulting in the production of recombinant Omp22 (rOmp22), which was verified using western blot. PDANPs were synthesized using dopamine monomers and loaded with rOmp22 through physical adsorption. The rOmp22-loaded PDANPs were characterized in terms of size, size distribution, zeta potential, field emission scanning electron microscopy (FESEM), loading capacity, Fourier transform infrared spectroscopy (FTIR), release profile, and cytotoxicity. In the in vivo phase, the adjuvant effect of rOmp22-loaded PDANPs was evaluated in terms of eliciting immune responses, including humoral and cytokine levels (IL-4, IL-17, and IFN-γ), as well as protection challenge. The rOmp22-loaded PDANPs were spherical with a size of 205 nm, a zeta potential of -14 mV, and a loading capacity of approximately 35.7 %. The released rOmp22 from nontoxic rOmp22-loaded PDANPs over 20 days was approximately 41.5 %, with preserved rOmp22 integrity. The IgG2a/IgG1 ratio and IFN-γ levels were significantly higher in immunized mice with rOmp22-loaded-PDANPs than in rOmp22-alum, naive Omp22, and control groups. Furthermore, rOmp22-loaded PDANPs induced effective protection against infection in the experimental challenge and showed more normal structures in the lung histopathology assay. The results of this study suggest the potential of PDANPs as a nano-adjuvant for inducing strong immune responses to combat A. baumannii.

Identification rate of Legionella species in non-purulent sputum culture is comparable to that in purulent sputum culture in Legionella pneumonia

Many Legionella pneumonia patients do not produce sputum, and it is unknown whether purulent sputum is required for the identification of Legionella species. This study aimed to evaluate the identification rate of Legionella species based on sputum quality and the factors predictive of Legionella infection. This study included Legionella pneumonia patients at Kurashiki Central Hospital from November 2000 to December 2022. Sputum quality, based on gram staining, was classified as the following: Geckler 1/2, 3/6 and 4/5. Geckler 4/5 was defined as purulent sputum. The sputa of 104 of 124 Legionella pneumonia patients were cultured. Fifty-four patients (51.9%) were identified with Legionella species, most of which were Legionella pneumophila serogroup 1 (81.5%). The identification rates of Legionella species according to sputum quality were 57.1% (16/28) in Geckler 1/2 sputum, 50.0% (34/68) in Geckler 3/6 sputum, and 50.0% (4/8) in Geckler 4/5 sputum, which were not significantly different (P = 0.86). On multivariate analysis, pre-culture treatment with anti-Legionella antimicrobials (odds ratio [OR] 0.26, 95% confidence interval [CI] 0.06-0.91), Pneumonia Severity Index class ≥IV (OR 2.57 [95% CI 1.02-6.71]), and intensive care unit admission (OR 3.08, 95% CI 1.06-10.09) correlated with the ability to identify Legionella species, but sputum quality did not (OR 0.88, 95% CI 0.17-4.41). The identification rate of Legionella species in non-purulent sputum was similar to that in purulent sputum. For the diagnosis of Legionella pneumonia, sputum should be collected before administering anti-Legionella antibiotics and cultured regardless of sputum quality.

A novel hybridization capture method for direct whole genome sequencing of clinical specimens to inform Legionnaires' disease investigations

The unprecedented precision and resolution of whole genome sequencing (WGS) can provide definitive identification of infectious agents for epidemiological outbreak tracking. WGS approaches, however, are frequently impeded by low pathogen DNA recovery from available primary specimens or unculturable samples. A cost-effective hybrid capture assay for Legionella pneumophila WGS analysis directly on primary specimens was developed. DNA from a diverse range of sputum and autopsy specimens PCR-positive for L. pneumophila serogroup 1 (LPSG1) was enriched with this method, and WGS was performed. All tested specimens were determined to be enriched for Legionella reads (up to 209,000-fold), significantly improving the discriminatory power to compare relatedness when no clinical isolate was available. We found the WGS data from some enriched specimens to differ by less than five single-nucleotide polymorphisms (SNPs) when compared to the WGS data of a matched culture isolate. This testing and analysis retrospectively provided previously unconfirmed links to environmental sources for clinical specimens of sputum and autopsy lung tissue. The latter provided the additional information needed to identify the source of these culture-negative cases associated with the South Bronx 2015 Legionnaires' disease (LD) investigation in New York City. This new method provides a proof of concept for future direct clinical specimen hybrid capture enrichment combined with WGS and bioinformatic analysis during outbreak investigations.IMPORTANCELegionnaires' disease (LD) is a severe and potentially fatal type of pneumonia primarily caused by inhalation of Legionella-contaminated aerosols from man-made water or cooling systems. LD remains extremely underdiagnosed as it is an uncommon form of pneumonia and relies on clinicians including it in the differential and requesting specialized testing. Additionally, it is challenging to obtain clinical lower respiratory specimens from cases with LD, and when available, culture requires specialized media and growth conditions, which are not available in all microbiology laboratories. In the current study, a method for Legionella pneumophila using hybrid capture by RNA baiting was developed, which allowed us to generate sufficient genome resolution from L. pneumophila serogroup 1 PCR-positive clinical specimens. This new approach offers an additional tool for surveillance of future LD outbreaks where isolation of Legionella is not possible and may help solve previously unanswered questions from past LD investigations.

Non-tuberculous mycobacterial pulmonary infection presenting in a patient with unilateral pulmonary artery agenesis

People who have structural or developmental lung disease are more likely to develop non-tuberculous mycobacterial infections. We present the case of a young man in his 30s who had unilateral pulmonary artery agenesis on the right side and presented with a 6-month history of productive cough and fever. His CT scan showed nodular and cavitating lesions on the right side, and sputum analysis confirmed infection with Mycobacterium chimaera He had to undergo modifications in his treatment, including a change from rifampicin to rifabutin due to drug interactions and his amikacin had to be stopped due to signs of vestibular toxicity. Using a multidisciplinary approach, we were able to formulate an appropriate drug regimen for him, and he is now under regular follow-up with infectious diseases and respiratory medicine.

Does post acute care reduce the mortality of octogenarian and nonagenarian patients undergoing hip fracture surgery?

BACKGROUND

With the increasing number of elderly individuals worldwide, a greater number of people aged 80 years and older sustain fragility fracture due to osteopenia and osteoporosis.

METHODS

This retrospective study included 158 older adults, with a median age of 85 (range: 80-99) years, who sustained hip fragility fracture and who underwent surgery. The patients were divided into two groups, one including patients who joined the post-acute care (PAC) program after surgery and another comprising patients who did not. The mortality, complication, comorbidity, re-fracture, secondary fracture, and readmission rates and functional status (based on the Barthel index score, numerical rating scale score, and Harris Hip Scale score) between the two groups were compared.

RESULTS

The patients who presented with fragility hip fracture and who joined the PAC rehabilitation program after the surgery had a lower rate of mortality, readmission rate, fracture (re-fracture and secondary fracture), and complications associated with fragility fracture, such as urinary tract infection, cerebrovascular accident, and pneumonia (acute coronary syndrome, out-of-hospital cardiac arrest, or in-hospital cardiac arrest.

CONCLUSIONS

PAC is associated with a lower rate of mortality and complications such as urinary tract infection, bed sore, and pneumonia in octogenarian and nonagenarian patients with hip fragility fracture.

Patient experience with bronchoscopy: topical versus monitored anesthesia

BACKGROUND

This study aimed to compare patient experiences during bronchoscopy procedures using either topical anesthesia (TA) or monitored anesthesia care (MA). The goal was to identify circumstances where patients could achieve similar levels of tolerance and satisfaction using only TA, especially in resource-limited settings.

METHODS

This study included consecutive patients who underwent bronchoscopy with either TA or MA. Data collected included demographics, indications for bronchoscopy, procedure time, and complications during the procedure. A quality assurance survey was administered to assess patient experience and satisfaction with both procedures. A pre-specified subgroup analysis was performed based on procedure invasiveness and time.

RESULTS

This study enrolled 350 (TA 251; MA 99) patients, with an average age of 65 years. Main indications for bronchoscopy included tumor diagnosis (38%), esophageal cancer staging (18%), and pulmonary infection (17%). The average duration of the procedures was 20 min, with MA being associated with a significantly longer procedure time than TA (31 min vs. 16 min; P < 0.001). The overall satisfaction rating with bronchoscopy was significantly higher in the MA group (visual analogue scale, 8.9 vs. 8.2; P = 0.001). Subgroup analyses showed that when less invasive or shorter procedures were performed, TA patients reported tolerance and satisfaction levels comparable to MA patients.

CONCLUSIONS

Bronchoscopy with MA offered patients a better experience and greater satisfaction; however, in settings with limited resources, TA alone may provide similar levels of patient tolerance and satisfaction during less invasive or shorter procedures.

Neonatal Bacillus cereus: an unusual case of congenital pneumonia requiring ECMO

A term neonate presented with cyanosis from birth, with refractory hypoxaemia despite intubation, administration of 100% oxygen and inhaled nitric oxide. Structural congenital heart disease was excluded. He developed profuse pulmonary haemorrhage at 6 hours of life with worsening hypoxia and was transferred to a paediatric intensive care unit (PICU) for initiation of veno-venous extracorporeal membrane oxygenation (vvECMO). Endotracheal aspirates from both the birth hospital and the PICU were positive for Bacillus cereus, with all other investigations finding no alternative cause for his presentation. Of note, mother was a practising veterinarian raising another potential source of exposure to this pathogen. A full recovery occurred after a total of 5 days of vvECMO, 13 days of ventilation and 20 days of PICU stay.

Study on the inhibition activity and mechanism of Tanreqing against Klebsiella pneumoniae biofilm formation in vitro and in vivo

Objective

To evaluate the antibacterial effect of Tanreqing (TRQ) against K. pneumoniae and its inhibition activity on bacterial biofilm formation in vitro and in vivo, and to explore the mechanism of the inhibitory effects of TRQ on K. pneumoniae biofilm formation.

Methods

An in vitro biofilm model of K. pneumoniae was established, and the impact of TRQ on biofilm formation was evaluated using crystal violet staining and scanning electron microscopy (SEM). Furthermore, the clearance effect of TRQ against K. pneumoniae in the biofilm was assessed using the viable plate counting method; q-RT PCR was used to evaluate the inhibitory effect of different concentrations of TRQ on the expression of biofilm-related genes in Klebsiella pneumoniae; The activity of quorum sensing signal molecule AI-2 was detected by Vibrio harveyi bioluminescence assay; Meanwhile, a guinea pig lung infection model of Klebsiella pneumoniae was constructed, and after treated with drugs, pathological analysis of lung tissue and determination of bacterial load in lung tissue were performed. The treatment groups included TRQ group, imipenem(IPM) group, TRQ+IPM group, and sterile saline group as the control.

Results

The formation of K. pneumoniae biofilm was significantly inhibited by TRQ in vitro experiments. Furthermore, when combined with IPM, the clearance of K. pneumoniae in the biofilm was notably increased compared to the TRQ group and IPM group alone. q-RT PCR analysis revealed that TRQ down-regulated the expression of genes related to biofilm formation in K. pneumoniae, specifically luxS, wbbm, wzm, and lsrK, and also inhibited the activity of AI-2 molecules in the bacterium. In vivo experiments demonstrated that TRQ effectively treated guinea pig lung infections, resulting in reduced lung inflammation. Additionally, when combined with IPM, there was a significant reduction in the bacterial load in lung tissue.

Conclusion

TRQ as a potential therapeutic agent plays a great role in the treatment of K. pneumoniae infections, particularly in combination with conventional antibiotics. And TRQ can enhanced the clearance effect on the bacterium by inhibiting the K. pneumoniae biofilm formation, which provided experimental evidence in support of clinical treatment of TRQ against K. pneumoniae infections.

Vitamin D constrains inflammation by modulating the expression of key genes on Chr17q12-21.1

Vitamin D possesses immunomodulatory functions and vitamin D deficiency has been associated with the rise in chronic inflammatory diseases, including asthma (Litonjua and Weiss, 2007). Vitamin D supplementation studies do not provide insight into the molecular genetic mechanisms of vitamin D-mediated immunoregulation. Here, we provide evidence for vitamin D regulation of two human chromosomal loci, Chr17q12-21.1 and Chr17q21.2, reliably associated with autoimmune and chronic inflammatory diseases. We demonstrate increased vitamin D receptor (Vdr) expression in mouse lung CD4+ Th2 cells, differential expression of Chr17q12-21.1 and Chr17q21.2 genes in Th2 cells based on vitamin D status and identify the IL-2/Stat5 pathway as a target of vitamin D signaling. Vitamin D deficiency caused severe lung inflammation after allergen challenge in mice that was prevented by long-term prenatal vitamin D supplementation. Mechanistically, vitamin D induced the expression of the Ikzf3-encoded protein Aiolos to suppress IL-2 signaling and ameliorate cytokine production in Th2 cells. These translational findings demonstrate mechanisms for the immune protective effect of vitamin D in allergic lung inflammation with a strong molecular genetic link to the regulation of both Chr17q12-21.1 and Chr17q21.2 genes and suggest further functional studies and interventional strategies for long-term prevention of asthma and other autoimmune disorders.

Investigation on the correlation factors of positive Streptococcus pneumoniae antibody and IgG antibody level of Streptococcus pneumoniae in the elderly over 60 years old in Shenzhen

BACKGROUND

Pneumococcal Polysaccharide Vaccine (PPV-23), designed to protect against the most common serotype of Streptococcus pneumoniae, is intended to protect the elderly and other high-risk groups. However, the immunogenicity of all 23 pneumococcal polysaccharide vaccines in older adults has not been thoroughly studied.

OBJECTIVE

The purpose of this study is to look into the factors that influence the effect of the pneumonia vaccine on the elderly over 60 years old in Shenzhen, as well as their IgG antibody level against Streptococcus pneumoniae.

METHODS

To determine the immune effectiveness of pneumococcal vaccination in older adults over 60 years old, we used the 3rd generation enzyme-linked immunosorbent assay to detect the antibody level of older adults to all 23 pneumococcal polysaccharide vaccines following pneumococcal immunization.

RESULTS

Vaccination, the number of physical examinations, pneumonia knowledge, and the pneumonia vaccination policy of the elderly in Shenzhen were all positively correlated with Streptococcus pneumoniae antibody positivity. The distribution of subtypes did not differ between elderly adults (over 65) and younger adults (under 65). The GMCs of IgG antibodies to PPS were significantly lower in males than in females for types 7f, 18c and 19a. At the same time, we found that people with chronic respiratory disease have lower type 9n than people without chronic respiratory disease. Other chronic diseases, such as hypertension and diabetes, had no difference in subtype distribution.

CONCLUSION

There was a statistically significant difference in antibody positivity rates for older people with more frequent medical check-ups in Shenzhen, indicating that publicity is playing a role. The effects of age, gender, and chronic diseases on naturally acquired anti-PPS IgG differ.

Influence of Procedural Volume on the Outcome of Gastric Endoscopic Submucosal Dissection: A Nationwide Population-Based Study Using Administrative Data

BACKGROUND & AIMS

Endoscopic submucosal dissection (ESD) is a well-established treatment modality for gastric neoplasms. We aimed to investigate the effect of procedural volume on the outcome of ESD for gastric cancer or adenoma.

METHODS

In this population-based cohort study, patients who underwent ESD for gastric cancer or adenoma from November 2011 to December 2017 were identified using the Korean National Health Insurance Service database. Operational definitions to identify the target population and post-procedural complications were created using diagnosis and procedure codes and were validated using hospital medical record data. Outcomes included hemorrhage, perforation, pneumonia, 30-day mortality, a composite outcome comprising all of these adverse outcomes, and additional resection. Hospital volume was categorized into 3 groups based on the results of the threshold analysis: high-, medium-, low-volume centers (HVCs, MVCs, and LVCs, respectively). Inverse probability of treatment weighting analysis was applied to enhance comparability across the volume groups.

RESULTS

There were 94,246 procedures performed in 88,687 patients during the study period. There were 5886 composite events including 4925 hemorrhage, 447 perforation, and 703 pneumonia cases. There were significant differences in ESD-related adverse outcomes among the 3 hospital volume categories, showing that HVCs and MVCs were associated with a lower risk of a composite outcome than LVCs (inverse probability of treatment-weighted odds ratio [OR], 0.651; 95% CI, 0.521-0.814; inverse probability of treatment-weighted OR, 0.641; 95% CI, 0.534-0.769). Similar tendencies were also shown for hemorrhage, perforation, and pneumonia; however, these were not evident for additional resection.

CONCLUSIONS

Procedural volume was closely associated with clinical outcome in patients undergoing ESD for gastric cancer or adenoma.

Differences in clinical characteristics of early-onset and late-onset severe acute respiratory syndrome coronavirus 2 infections in neonates

Differences in clinical characteristics of early-onset and late-onset severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections in neonates remain unclear. This study aimed to determine whether there are differences in the main clinical, radiological, and laboratory features of early-onset and late-onset SARS-CoV-2 infections in neonates. This single-center, prospective cohort study enrolled neonates with SARS-CoV-2 infection from December 7, 2022, to January 3, 2023, and evaluated their clinical characteristics during hospitalization. All neonates (N = 58) infected with SARS-CoV-2 within 28 days of birth who were admitted to the neonatal intensive care unit of Taizhou Hospital were included. These neonates were classified into the early-onset (diagnosed within 7 days of birth) and late-onset (diagnosed more than 7 days after birth) groups. The symptoms, treatment, and prognosis of SARS-CoV-2 infection were the main study outcomes. The incidence of hospitalization attributable to SARS-CoV-2 infection was 10.6% (58 of 546 neonates) in Linhai. Sixteen (28%) of the 58 SARS-CoV-2 infections were early-onset cases, and 42 (72%) were late-onset cases. The common symptoms among the late-onset group were fever (p < 0.001) and cough (p < 0.001). Neonates with late-onset SARS-CoV-2 infection (p < 0.001) were significantly more likely to develop pneumonia.  Conclusion: The clinical symptoms and rates of pneumonia caused by SARS-CoV-2 infection in neonates differed between the early-onset and late-onset groups. Different clinical management is necessary for neonates with early-onset and late-onset SARS-CoV-2 infections. What is Known: • Neonates are susceptible to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). • Differences in clinical characteristics of early-onset and late-onset SARS-CoV-2 infections in neonates remain unclear. What is New: • Fever and cough were the most common symptoms among neonates with late-onset infection. • Neonates with late-onset SARS-CoV-2 infection were more likely to develop pneumonia.

Comparative study of imaging and pathology of primary mucinous adenocarcinoma with different imaging manifestations

BACKGROUND

Pulmonary mucinous adenocarcinoma is a special type of lung cancer. Its imaging manifestations are diverse, which brings challenges to clinical diagnosis. However, its formation mechanism is unclear.

OBJECTIVE

The objective of this study is to analyse the relevant mechanisms of the formation of pulmonary mucinous adenocarcinoma by observing its different imaging and pathological manifestations.

DATA AND METHODS

Retrospective analysis was conducted on imaging manifestations and pathological data of 103 patients with pulmonary mucinous adenocarcinoma confirmed intraoperatively or pathologically.

RESULTS

Forty-three patients had pulmonary mucinous adenocarcinoma with a solitary nodule/mass, 41 patients with localized pneumonia and 19 patients with diffuse pneumonia. Their CT manifestations included 'falling snowflake sign', ground-glass opacity close to the heart, vacuous signs/honeycombing and withered tree branches. Under the microscope, all the three types of pulmonary mucinous adenocarcinoma had visibly formed mucus lakes but were made of tumour cells with totally different shapes, which included the goblet-like shape (tall column-like shape) and quasi-circular shape. Tall column-shaped tumour cells were negative or weakly positive for thyroid transcription factor-1 (TTF-1) and strongly positive for ALK mutation, whereas quasi-circular tumour cells were positive for TTF-1 and less positive for ALK mutation.

CONCLUSION

The different imaging manifestations of mucinous adenocarcinoma are possibly due to the different amounts or viscosity of mucus produced, and the mechanisms of its formation may include (1) tumour cells in different shapes have different abilities to produce mucus; (2) tumours in different stages produce different amounts or viscosity of mucus; and (3) the TTF-1 and ALK genes affect the production of mucus.

LIRAGLUTIDE ALLEVIATES ACUTE LUNG INJURY AND MORTALITY IN PNEUMONIA-INDUCED SEPSIS THROUGH REGULATING SURFACTANT PROTEIN EXPRESSION AND SECRETION

ABSTRACT

Glucagon-like peptide 1 (GLP-1) analogs are used to treat type 2 diabetes, and they can regulate insulin secretion, energy homeostasis, inflammation, and immune cell function. This study sought to determine whether the GLP-1 analog liraglutide exerts a beneficial action in an acute lung injury model of pneumonia-induced sepsis. Methods: Wild-type FVB/NJ mice (n = 114) were infected by intratracheal injection with Pseudomonas aeruginosa Xen5 (4 × 10 4 CFU/mouse) or an equal volume (50 μL) of saline (control) with or without a subcutaneous injection of liraglutide (2 mg/kg, 30 min after infection). Mice were killed 24 h after infection. Lung tissues and BALF were analyzed. In separate experiments, the dynamic growth of bacteria and animal mortality was monitored using in vivo imaging system within 48 h after infection. In addition, primary lung alveolar type II cells isolated from mice were used to study the mechanism of liraglutide action. Result: Liraglutide improved survival ( P < 0.05), decreased bacterial loads in vivo , and reduced lung injury scores ( P < 0.01) in septic mice. Liraglutide-treated mice showed decreased levels of inflammatory cells ( P < 0.01) and proinflammatory cytokines (TNF-α and IL-6) ( P < 0.01) in the lung compared with septic controls. Liraglutide significantly increased pulmonary surfactant proteins (SP-A and SP-B) expression/secretion ( P < 0.01) and phospholipid secretion ( P < 0.01) in vivo . Primary alveolar type II cells pretreated with liraglutide improved SP-A and SP-B expression after LPS exposure ( P < 0.01). Conclusion: Liraglutide attenuates mortality and lung inflammation/injury in pneumonia-induced sepsis. The increased surfactant expression/secretion and anti-inflammatory effects of liraglutide represent potential mechanisms by GLP-1 agonists potentiate host defense and maintain alveolar respiratory function in acute lung injury.

The Role of Complement Component C3 in Protection Against Pseudomonas Pneumonia-Induced Lung Injury

The complement system is a family of proteins that facilitate immune resistance by attacking microbes to decrease pathogen burden. As a result, deficiencies of certain complement proteins result in recurrent bacterial infections, and can also result in acute lung injury (ALI). We and others have shown that C3 is present in both immune and nonimmune cells, and modulates cellular functions such as metabolism, differentiation, cytokine production, and survival. Although the emerging roles of the complement system have implications for host responses to ALI, key questions remain vis-a-vis the lung epithelium. In this review, we summarize our recent article in which we reported that during Pseudomonas aeruginosa-induced ALI, lung epithelial cell-derived C3 operates independent of liver-derived C3. Specifically, we report the use of a combination of human cell culture systems and global as well as conditional knockout mouse models to demonstrate the centrality of lung epithelial cell-derived C3. We also summarize recent articles that have interrogated the role of intracellular and/or locally derived C3 in host defense. We propose that C3 is a highly attractive candidate for enhancing tissue resilience in lung injury as it facilitates the survival and function of the lung epithelium, a key cell type that promotes barrier function.

Liposomes for Inhalation

Inhalation of liposomes formulated with phospholipids similar to endogenous lung surfactants and lipids offers biocompatibility and versatility within the pulmonary medicine field to treat a range of diseases such as lung cancer, cystic fibrosis and lung infections. Manipulation of the physicochemical properties of liposomes enables innovative design of the carrier to meet specific delivery, release and targeting requirements. This delivery system offers several benefits: improved pharmacokinetics with reduced toxicity, enhanced therapeutic efficacy, increased delivery of poorly soluble drugs, taste masking, biopharmaceutics degradation protection and targeted cellular therapy. This section provides an overview of liposomal formulation and delivery, together with their applications for different disease states in the lung.

Early Versus Late Tracheostomy in Patients with Traumatic Brain Injury: A US Nationwide Analysis

BACKGROUND

One of the most critical issues in patients suffering from traumatic brain injury (TBI) is protecting the airway and attempting to keep a secure airway. It is evident that tracheostomy in patients with TBI after 7-14 days can have favorable outcomes if the patient cannot be extubated; however, some clinicians have recommended early tracheostomy before 7 days.

METHODS

A retrospective cohort of inpatient study participants was queried from the National Inpatient Sample to include patients with TBI between 2016 and 2020 undergoing tracheostomy and outcomes between the two groups of early tracheostomy (ET) (< 7 days from admission) and late tracheostomy (LT) (≥ 7 days from admission) were compared.

RESULTS

We reviewed 219,005 patients with TBI, out of whom 3.04% had a tracheostomy. Patients in the ET group were younger than those in the LT group (45.02 ± 19.38 years old vs. 48.68 ± 20.50 years old, respectively, p < 0.001), mainly men (76.64% vs. 73.73%, respectively, p = 0.01), and mainly White race (59.88% vs. 57.53%, respectively, p = 0.33). The patients in the ET group had a significantly shorter length of stay as compared with those in the LT group (27.78 ± 25.96 days vs. 36.32 ± 29.30 days, respectively, p < 0.001) and had a significantly lower hospital charge ($502,502.436 ± 427,060.81 vs. $642,739.302 ± 516,078.94 per patient, respectively, p < 0.001). The whole TBI cohort mortality was reported at 7.04%, which was higher within the ET group compared with the LT group (8.69% vs. 6.07%, respectively, p < 0.001). Patients in the LT had higher odds of developing any infection (odds ratio [OR] 1.43 [1.22-1.68], p < 0.001), emerging sepsis (OR 1.61 [1.39-1.87], p < 0.001), pneumonia (OR 1.52 [1.36-1.69], p < 0.001), and respiratory failure (OR 1.30 [1.09-1.55], p = 0.004).

CONCLUSIONS

This study shows that ET can provide notable and significant benefits for patients with TBI. Future high-quality prospective studies should be performed to investigate and shed more light on the ideal timing of tracheostomy in patients with TBI.

Downregulation of circ_0035292 Alleviates LPS-Induced WI-38 Cell Injury via Targeting miR-494-3p/TLR4 Pathway in Infantile Pneumonia

Circular RNAs (circRNAs) have been confirmed to mediate infantile pneumonia development. In this, we investigated the role and new mechanism of circ_0035292 regulating infantile pneumonia progression. Lipopolysaccharide (LPS)-treated WI-38 cells were used to mimic infantile pneumonia cell injury models. Quantitative real-time PCR was used to measure circ_0035292, microRNA (miR)-494-3p and toll-like receptor 4 (TLR4). Cell proliferation and apoptosis were assessed by MTT assay, EdU assay, and flow cytometry. Protein expression was tested using western blot analysis. Inflammation and oxidative stress were evaluated by measuring IL-6, IL-1β, MDA and SOD levels using ELISA assay and corresponding kits. RNA interaction was confirmed by dual-luciferase reporter assay and RIP assay. Circ_0035292 had elevated expression in infantile pneumonia patients and LPS-induced WI-38 cells. Silenced circ_0035292 could enhance WI-38 cell proliferation, while suppress apoptosis, inflammation and oxidative stress under LPS treatment. Mechanically, circ_0035292 targeted miR-494-3p to positively regulate TLR4. The rescue experiments indicated that miR-494-3p inhibitor abolished the function of circ_0035292 knockdown, and TLR4 overexpression reversed the inhibitory effect of miR-494-3p on LPS-induced WI-38 cell injury. Circ_0035292 might be a potential target for infantile pneumonia treatment, which knockdown could relieve LPS-induced cell injury via the regulation of miR-494-3p/TLR4 axis.

Are immune checkpoint inhibitors safe and effective in lung cancer patients with pre-existing interstitial lung disease?

Aim: This study aims to clarify the efficacy and adverse effects of immune checkpoint inhibitors (ICIs) in the lung cancer patients with a history of interstitial lung disease (ILD). Methods: From the inception of the database to 4 April 2023, we systematically searched the four databases. Results: The objective remission rate, disease control rate, incidence of immune-associated pneumonitis (ICIP) in the combined ILD group were significantly higher than those in the non-combined ILD group. There were no significant differences between the two groups in progression-free survival, overall survival, renal insufficiency, thyroid dysfunction and gastrointestinal toxicity. Conclusion: Generally, a pre-existing ILD history can increase the efficacy and incidence of ICIs' adverse reactions. Therefore, ICIs should be administered with caution.

Severe Community-Acquired Pneumonia in Immunocompromised Patients

Due to higher survival rates with good quality of life, related to new treatments in the fields of oncology, hematology, and transplantation, the number of immunocompromised patients is increasing. But these patients are at high risk of intensive care unit admission because of numerous complications. Acute respiratory failure due to severe community-acquired pneumonia is one of the leading causes of admission. In this setting, the need for invasive mechanical ventilation is up to 60%, associated with a high hospital mortality rate of around 40 to 50%. A wide range of pathogens according to the reason of immunosuppression is associated with severe pneumonia in those patients: documented bacterial pneumonia represents a third of cases, viral and fungal pneumonia both account for up to 15% of cases. For patients with an undetermined etiology despite comprehensive diagnostic workup, the hospital mortality rate is very high. Thus, a standardized diagnosis strategy should be defined to increase the diagnosis rate and prescribe the appropriate treatment. This review focuses on the benefit-to-risk ratio of invasive or noninvasive strategies, in the era of omics, for the management of critically ill immunocompromised patients with severe pneumonia in terms of diagnosis and oxygenation.

Pulmonary infections with nontuberculous mycobacteria

This review focuses on the treatment of nontuberculous pulmonary disease caused by Mycobacterium avium complex and M. abscessus. It covers treatment indications, antibiotic choice, resistance and side effects. Treatment of nontuberculous pulmonary disease is complex, lengthy, and fraught with side effects. Increased attention on this disease is needed in order to alleviate the severe consequences of this growing disease. Cooperation between pulmonologists and infectious disease specialists is needed to ensure uniform treatment, and to account for the heterogeneity seen in patients and mycobacteria alike.