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Drug-resistant bacterial pneumonia presents a substantial challenge for targeted drug delivery to the infected lung site due to the existence of mucus and gas-blood barriers. Allicin, renowned for its extensive bioactivity, holds promise as an antimicrobial agent. However, its unregulated bioavailability restricts both its antibacterial and anti-inflammatory efficacy. As a result, precise targeting of the infection site for controlled drug release is crucial in the treatment of drug-resistant bacterial pneumonia. In this study, we developed a macrophage cell membrane-modified nanoallicin composite material (Allicin@MSN@CM) by utilizing cell membrane modification technology. By harnessing the homing ability of macrophage cell membranes to inflammatory sites, we enabled the active aggregation of nanomaterials during circulation within the body. Furthermore, α-hemolysin secreted by MRSA bacteria was employed to perforate the cell membrane, facilitating on-demand drug release at the infection site. In vitro antibacterial experiments demonstrated that the material possesses strong antibacterial properties, alongside good stability and biocompatibility. Additionally, in a mouse model of lung infection, it not only effectively eradicated bacteria but also reduced lung inflammation. This study provides valuable insights into the application of nanocarriers in delivering traditional Chinese medicine to address the challenges posed by bacterial drug-resistant pneumonia. [ABSTRACT FROM AUTHOR]

Background: Current guidelines recommend empiric antibiotic therapy for patients who require hospitalization for community-acquired pneumonia (CAP). We sought to determine whether clinical, imaging or laboratory features in patients hospitalized for CAP in whom PCR is positive for a respiratory virus enable exclusion of bacterial coinfection so that antibiotics can be withheld. Methods: For this prospective study, we selected patients in whom an etiologic diagnosis was likely to be reached, namely those who provided a high-quality sputum sample at or shortly after admission, and in whom PCR was done to test for a respiratory virus. We performed quantitative bacteriologic studies on sputum to determine the presence of bacterial infection or coinfection and reviewed all clinical, imaging and laboratory studies. Results: Of 122 CAP patients studied, 77 (63.1%) had bacterial infection, 16 (13.1%) viral infection, and 29 (23.8%) bacterial/viral coinfection. Underlying pulmonary disease and a history of smoking were more common in bacterial pneumonia. Upper respiratory symptoms were more common, and mean white blood cell (WBC) counts were lower viral pneumonia. Nevertheless, no clinical, laboratory or imaging findings allowed exclusion of bacterial coinfection in patients who tested positive for a respiratory virus. In fact, patients with bacterial/viral coinfection were sicker than those with bacterial or viral pneumonia; 30% were admitted required transfer to the ICU during their hospital course, compared to 17% and 19% of patients with bacterial or viral infection, respectively (p <.05). In this study, 64.4% of patients who tested positive for a respiratory virus had a bacterial coinfection. Conclusions: If a test for a respiratory virus test is positive in a patient hospitalized for CAP, no sufficiently differentiating features exclude bacterial coinfection, thereby supporting the recommendation that empiric antibiotics be administered to all patients who are sufficiently ill to require hospitalization for CAP. [ABSTRACT FROM AUTHOR]

Aim: The burden of respiratory disease is great among children. This study aimed to examine the temporal relationship between hospitalisation for respiratory syncytial virus (RSV) and bacterial pneumonia. Methods: A Swedish population‐based cohort was created by combining data from the Swedish Medical Birth Register, the National Inpatient Register, the Cause of Death Register, the Total Population Register, and the Longitudinal Integration Database for Health Insurance and Labour Market Studies. Children born between 1998 and 2015 were included and followed for 2 years. We examined the temporal relationship between RSV hospitalisation and bacterial pneumonia using piecewise exponential models. Results: The final cohort comprised 1 641 747 children, 48.5% were females. There were 23 632 RSV and 4722 bacterial pneumonia hospitalisations, with mean age of 137.8 and 424.2 days, respectively. RSV hospitalisation was associated with bacterial pneumonia with an adjusted incidence rate ratio (aIRR) of 3.18. The risk was highest in the first month after RSV hospitalisation, aIRR 11.19. The risk of bacterial pneumonia was elevated for 4 months after RSV hospitalisation and before RSV hospitalisation. Conclusion: We found an increased risk for bacterial pneumonia hospitalisation in children hospitalised for RSV both before and after RSV hospitalisation, indicating a bidirectional relationship. [ABSTRACT FROM AUTHOR]

In the last couple of years, deep learning models have been extensively used in the field of pneumonia detection using image processing. Making a real world chest X-Ray dataset takes time and comes with a finite number of images. But in order to train an AI model from scratch, the need for readily-available, limitless and accurate data is of utmost importance. So, it is more prudent to use generative adversarial network (GAN). This technology converts a noise matrix to the desired image matrix. Undoubtedly the technique has been used by researchers in this field but our work tries to make this generated image more accurate using a specific GAN for each class of data. For each of the three classes of chest X-Ray images, namely bacterial, viral and normal, a GAN has been trained to provide images of utmost accuracy. We believe that specific GAN for each subgroup is capable of producing more accurate images in desired quantities, as the GAN itself is trained on focussed images and thereby not only helping to limit the problem of model overfitting but also perfecting the discriminators of each GAN. In our case we were able to reach similar levels of clarity in the high resolution images as compared to single chest X-Ray GAN in a lesser amount of time and using a lesser amount of training data. [ABSTRACT FROM AUTHOR]

Abstract Background Current guidelines recommend empiric antibiotic therapy for patients who require hospitalization for community-acquired pneumonia (CAP). We sought to determine whether clinical, imaging or laboratory features in patients hospitalized for CAP in whom PCR is positive for a respiratory virus enable exclusion of bacterial coinfection so that antibiotics can be withheld. Methods For this prospective study, we selected patients in whom an etiologic diagnosis was likely to be reached, namely those who provided a high-quality sputum sample at or shortly after admission, and in whom PCR was done to test for a respiratory virus. We performed quantitative bacteriologic studies on sputum to determine the presence of bacterial infection or coinfection and reviewed all clinical, imaging and laboratory studies. Results Of 122 CAP patients studied, 77 (63.1%) had bacterial infection, 16 (13.1%) viral infection, and 29 (23.8%) bacterial/viral coinfection. Underlying pulmonary disease and a history of smoking were more common in bacterial pneumonia. Upper respiratory symptoms were more common, and mean white blood cell (WBC) counts were lower viral pneumonia. Nevertheless, no clinical, laboratory or imaging findings allowed exclusion of bacterial coinfection in patients who tested positive for a respiratory virus. In fact, patients with bacterial/viral coinfection were sicker than those with bacterial or viral pneumonia; 30% were admitted required transfer to the ICU during their hospital course, compared to 17% and 19% of patients with bacterial or viral infection, respectively (p

Chenping Li, Zhi Chen, Jiaqi Shi, Xiuyun Zheng Department of Pulmonary and Critical Care Medicine (PCCM), The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, 325000, People’s Republic of ChinaCorrespondence: Xiuyun Zheng, Department of Pulmonary and Critical Care Medicine (PCCM), The First Affiliated Hospital of Wenzhou Medical University, 1210 University Town, Wenzhou, Zhejiang, People’s Republic of China, Email zhengxiuyun@wmu.edu.cnPurpose: Bacterial pneumonia is a prevalent respiratory disease and a primary cause of death among hospitalized patients. Ambroxol and loquat syrup are widely utilized pharmaceuticals for managing respiratory infections in China. This study investigates the potential application and efficacy of combining ambroxol with loquat syrup for treating bacterial pneumonia.Methods: In this study, mice with P. aeruginosa-induced bacterial pneumonia were used to evaluate the therapeutic effects of ambroxol, loquat syrup, and their combination. A bacterial plate coating assay was performed to measure the P. aeruginosa content in saliva, lung tissue, and bronchoalveolar lavage fluid (BALF). A plate colony counting assay was conducted to assess the antibacterial activity of ambroxol and loquat syrup. Serum, BALF, and lung tissues were analyzed using qPCR, ELISA, immunohistochemistry, and hematoxylin-eosin staining to evaluate disease severity.Results: In this study, the experimental results demonstrate that, compared to treatment with ambroxol and/or loquat syrup alone, the combined administration of ambroxol and loquat syrup significantly increases the volume of saliva expectorated by mice infected with bacteria, concurrently augmenting bacterial presence in saliva while diminishing bacterial burden in the lungs, with significant differences observed (p< 0.05). Furthermore, the combined therapy of ambroxol and loquat syrup achieved better therapeutic effects on P. aeruginosa pneumonia compared to ambroxol and/or loquat syrup alone (p< 0.05), as evidenced by significantly reduced P. aeruginosa-induced lung injury, improved lung permeability, decreased inflammatory cell infiltration, and lower expression of inflammatory cytokines.Conclusion: These findings suggest that the combination therapy of ambroxol and loquat syrup presents a safe and feasible new treatment strategy for bacterial pneumonia, offering promising benefits for ameliorating lung tissue damage and inflammation.Keywords: bacterial pneumonia, ambroxol, loquat syrup, combination therapy, inflammation, treatment strategy

Abstract Background The intricate interplay between genetics and immunology often dictates the host’s susceptibility to various diseases. This study explored the genetic causal relationship between natural killer (NK) cell-related traits and the risk of infection. Methods Single-nucleotide polymorphisms (SNPs) significantly associated with NK cell-related traits were selected as instrumental variables to estimate their genetic causal effects on infection. SNPs from a genome-wide association study (GWAS) on NK cell-related traits, including absolute cell counts, median fluorescence intensities reflecting surface antigen levels, and relative cell counts, were used as exposure instruments. Summary-level GWAS statistics of four phenotypes of infection were used as the outcome data. The exposure and outcome data were analyzed via the two-sample Mendelian randomization method. Results Each one standard deviation increase in the expression level of human leukocyte antigen (HLA)-DR on HLA-DR+ NK cells was associated with a lower risk of pneumonia (P

Abstract Background Bacterial pneumonia is one of the most common causes of acute respiratory distress syndrome. In fulminant cases, when mechanical ventilation fails, veno-venous extracorporeal membrane oxygenation is required. However, this method is still associated with significant mortality and a wide range of potential complications. However, there are now many case reports of good outcomes even in patients with prolonged extracorporeal oxygenation, as in our rather complicated case report. Case presentation Our case report describes a complicated but successful treatment of a severe, devastating bacterial pneumonia in a 39-year-old European polymorbid woman with a rare form of diabetes mellitus, which had been poorly compensated for a long time with limited compliance, in the context of a combined immunodeficiency that strongly influenced the course of the disease. The patient’s hospitalization required a total of 30 days of veno-venous extracorporeal membrane oxygenation therapy and more than 50 days of mechanical ventilation. Numerous complications, particularly bleeding, required seven chest drains, two extracorporeal membrane oxygenation circuit changes, and one surgical revision. The patient’s mental state required repeated psychiatric intervention. Conclusion It is possible that even the initially severely damaged lung parenchyma can develop its regenerative potential if suitable conditions are provided for this process, including a sufficiently long period of extracorporeal membrane oxygenation. We believe that this case report may also contribute to the consideration of the indications and contraindications of extracorporeal support. The authors also discuss the limitations and risks of prolonged veno-venous extracorporeal membrane oxygenation support and periprocedural anticoagulation strategies.

Objective: To describe the clinical presentation and diagnosis of bilateral diaphragmatic paralysis in a weanling miniature donkey jack. Case Summary: A 5‐month‐old miniature donkey jack presented to a tertiary care facility for fever, cough, and increased respiratory rate and effort initially unresponsive to treatment with antimicrobials and anti‐inflammatories. Clinical and diagnostic evaluations found no evidence of upper respiratory obstruction or bacterial pneumonia. Serial arterial blood gas evaluations revealed hypercapnia and hypoxemia, and diagnostic imaging was consistent with bilateral diaphragmatic paralysis. The patient's nasal swab for equine influenza type A (subtype H3N8) was positive and had a mildly decreased whole blood selenium concentration. The donkey recovered after treatment with anti‐inflammatories and supportive care. New or Unique Information Provided: This case documents the first report of diaphragmatic paralysis in a donkey, with concurrent equine influenza infection offering a possible causal factor. Bilateral diaphragmatic paralysis should be considered as a differential diagnosis for respiratory distress in donkeys, particularly when diagnostic testing or treatment trials do not support more common causes of respiratory disease in adult animals, such as infectious lower airway disease, asthma, and pulmonary fibrosis. [ABSTRACT FROM AUTHOR]

Respiratory viral infections, including respiratory syncytial virus (RSV), parainfluenza viruses and type A and B influenza viruses, can have severe outcomes. Bacterial infections frequently follow viral infections, and influenza or other viral epidemics periodically have higher mortalities from secondary bacterial pneumonias. Most secondary bacterial infections can cause lung immunosuppression by fatty acid mediators which activate cellular receptors to manipulate neutrophils, macrophages, natural killer cells, dendritic cells and other lung immune cells. Bacterial infections induce synthesis of inflammatory mediators including prostaglandins and leukotrienes, then eventually also special pro-resolving mediators, including lipoxins, resolvins, protectins and maresins, which normally resolve inflammation and immunosuppression. Concurrent viral and secondary bacterial infections are more dangerous, because viral infections can cause inflammation and immunosuppression before the secondary bacterial infections worsen inflammation and immunosuppression. Plausibly, the higher mortalities of secondary bacterial pneumonias are caused by the overwhelming inflammation and immunosuppression, which the special pro-resolving mediators might not resolve. [ABSTRACT FROM AUTHOR]

Objectives Patients with reported Stenotrophomonas maltophilia (S. maltophilia) growth in lower respiratory tract samples were investigated. The results of these patients were assessed by clinicians as either infection or colonization. The data of patients considered to have S. maltophilia infection were compared to those considered to have colonization to explore factors associated with infection. Methods Parameters including as age, length of hospital stay, duration of S. maltophilia growth after hospital admission, sex, unit, department, specimen type, mechanical ventilation treatment status, antimicrobial susceptibility results, comorbidities, survival, and antimicrobials used during the period from hospital admission to S. maltophilia growth were investigated. Additionally, some biochemical parameters that were examined include the day of hospital admission, the day of sample collection when the bacterium was isolated (±1 day), and the day of discharge/died. Results The infection group had a significantly higher rate of admissions to internal medical departments and more cases of discharge/died. The infection group showed a lower amount of aminoglycoside antibiotic usage and significantly higher levels of BUN, creatinine, neutrophils, and neutrophil-to-lymphocyte ratio on their day of discharge/died. Conclusion Being admitted to internal medical departments and receiving aminoglycoside treatment were identified to be factors associated with S. maltophilia infection. These patients should be monitored for infection markers such as CRP and neutrophil count, as well as renal function tests. It should be noted that being infected with S. maltophilia is an independent risk factor for mortality. [ABSTRACT FROM AUTHOR]

Background: Bacterial pneumonia is one of the most common causes of acute respiratory distress syndrome. In fulminant cases, when mechanical ventilation fails, veno-venous extracorporeal membrane oxygenation is required. However, this method is still associated with significant mortality and a wide range of potential complications. However, there are now many case reports of good outcomes even in patients with prolonged extracorporeal oxygenation, as in our rather complicated case report. Case presentation: Our case report describes a complicated but successful treatment of a severe, devastating bacterial pneumonia in a 39-year-old European polymorbid woman with a rare form of diabetes mellitus, which had been poorly compensated for a long time with limited compliance, in the context of a combined immunodeficiency that strongly influenced the course of the disease. The patient's hospitalization required a total of 30 days of veno-venous extracorporeal membrane oxygenation therapy and more than 50 days of mechanical ventilation. Numerous complications, particularly bleeding, required seven chest drains, two extracorporeal membrane oxygenation circuit changes, and one surgical revision. The patient's mental state required repeated psychiatric intervention. Conclusion: It is possible that even the initially severely damaged lung parenchyma can develop its regenerative potential if suitable conditions are provided for this process, including a sufficiently long period of extracorporeal membrane oxygenation. We believe that this case report may also contribute to the consideration of the indications and contraindications of extracorporeal support. The authors also discuss the limitations and risks of prolonged veno-venous extracorporeal membrane oxygenation support and periprocedural anticoagulation strategies. [ABSTRACT FROM AUTHOR]

Background: The intricate interplay between genetics and immunology often dictates the host’s susceptibility to various diseases. This study explored the genetic causal relationship between natural killer (NK) cell-related traits and the risk of infection. Methods: Single-nucleotide polymorphisms (SNPs) significantly associated with NK cell-related traits were selected as instrumental variables to estimate their genetic causal effects on infection. SNPs from a genome-wide association study (GWAS) on NK cell-related traits, including absolute cell counts, median fluorescence intensities reflecting surface antigen levels, and relative cell counts, were used as exposure instruments. Summary-level GWAS statistics of four phenotypes of infection were used as the outcome data. The exposure and outcome data were analyzed via the two-sample Mendelian randomization method. Results: Each one standard deviation increase in the expression level of human leukocyte antigen (HLA)-DR on HLA-DR+ NK cells was associated with a lower risk of pneumonia (P < 0.05). An increased HLA-DR+ NK/CD3− lymphocyte ratio was related to a lower of risk of pneumonia (P < 0.05). Each one standard deviation increase in the absolute count of HLA-DR+ NK cells was associated with a lower risk of both bacterial pneumonia and pneumonia (P < 0.05). An increased HLA-DR+ NK/NK ratio was associated with a decreased risk of both pneumonia and bacterial pneumonia (P < 0.05). The results were robust under all sensitivity analyses. No evidence for heterogeneity, pleiotropy, or potential reverse causality was detected. Notably, our analysis did not reveal any significant associations between NK cell-related traits and other phenotypes of infection, including cellulitis, cystitis, and intestinal infection. Conclusions: HLA-DR+ NK cells could be a novel immune cell trait associated with a lower risk of bacterial pneumonia or pneumonia. [ABSTRACT FROM AUTHOR]

Background: COVID-19 began in December 2019, rapidly spreading worldwide. China implemented a dynamic zero-COVID strategy and strict control measures after the outbreak. However, Guangzhou city ended closed-off management by the end of November 2022, leading to exposure to SARS-CoV-2. Despite most hospitalized patients being infected or co-infected with SARS-CoV-2, some remained uninfected. We report two cases of bacterial pneumonia with elevated globulin levels not infected with SARS-CoV-2, aiming to identify protection factors of SARS-CoV-2 infection and provide a scientific basis for SARS-CoV-2 prevention. Case presentation: Case 1, a 92-year-old male, admitted on October 21, 2022, developed worsening cough and sputum after aspiration, diagnosed with bacterial pneumonia with Pseudomonas aeruginosa, Escherichia coli (CRE) and carbapenem-resistant Acinetobacter baumannii (CRAB) infections. He was treated with imipenem anti-infective therapy and mechanical ventilation, then switched to a combination of meropenem, voriconazole and amikacin antiinfective therapy due to recurrent infections and septic shock, and died of sepsis on 8 January 2023. Case 2 is an 82-year-old male admitted on 30 September 2022, with recurrent cough, sputum, and shortness of breath, diagnosed with bacterial pneumonia with carbapenem-resistant Klebsiella pneumoniae (CRKP) and Mycobacterium pneumoniae infections. He was treated with ventilator-assisted ventilation, meropenem, amikacin, tigecycline and mucomycin nebulization and discharged with improvement on 26 October. He was readmitted on 21 November 2022 and diagnosed with bacterial pneumonia. He was treated with cefoperazone sulbactam, amikacin, meropenem and fluconazole and discharged on 31 December. Neither patient was infected with SARS-CoV-2 during hospitalization. Notably, their globulin levels were elevated before SARS-CoV-2 exposure, gradually decreasing afterward. Conclusions: Patients with bacterial pneumonia with high globulin levels likely have large amounts of immunoglobulin, and that immunoglobulin crossreactivity causes this protein to be involved in clearing SARS-CoV-2 and preventing infection. Therefore, bacterial pneumonia patients with high globulin levels included in this study were not infected with SARS-CoV-2. After exposure to SARS-CoV-2, the amount of globulin in the patient's body was reduced because it was used to clear SARS-CoV-2. The results of this study are expected to provide a theoretical basis for the study of the mechanism of prevention and treatment of SARS-CoV-2 infection. [ABSTRACT FROM AUTHOR]

Three cats, aged 2 to 11 years, presented to the University of Minnesota Veterinary Diagnostic Laboratory over a 3-year period following euthanasia or death due to respiratory distress. Thoracic radiographs revealed nodular, soft tissue opacities throughout the lung fields in all cases. On postmortem examination, approximately 60% to 80% of the lung parenchyma were expanded by multifocal to coalescing, well-demarcated, beige, semi-firm nodules. Histologically, large numbers of neutrophils, fewer macrophages, fibrin, and cellular and karyorrhectic debris effaced the pulmonary parenchyma. The inflammatory foci contained aggregates of gram-negative cocci. 16s rRNA Sanger sequencing and whole-genome sequencing identified the bacteria isolated from the lung of all cats under aerobic conditions as a novel Neisseria spp. Based on whole-genome sequence analysis, all 3 sequences shared 92.71% and 92.67% average nucleotide identity with closely related Neisseria animaloris NZ LR134440T and Neisseria animaloris GCA 002108605T, respectively. The in silico DNA-DNA hybridization identity compared to our isolates was 46.6% and 33.8% with strain DSM Neisseria zoodegmatis 21642 and strain DSM 21643, respectively. All 3 sequences have less than 95% average nucleotide identity and less than 70% DNA-DNA hybridization identity, suggesting that the 3 isolates are a novel species of the genus Neisseria. Infection with Neisseria spp. induces an embolic pneumonia in cats that radiographically and pathologically resembles a metastatic neoplastic process and should be considered among the etiologic differential diagnoses in cases of infectious pulmonary disease with a disseminated, nodular lung pattern. [ABSTRACT FROM AUTHOR]

The study was designed to determine level of lungs inflammation and associated bacterial flora that influenced gross and histopathological lesions related to bovine pneumonic lungs amongst cattle slaughter in Maiduguri central abattoir. The study was conducted in Maiduguri, North-Eastern Nigeria. A total of 100 pneumonic lungs sampled from cattle slaughtered at Maiduguri central abattoir, 63 (63 %) were positive isolate and 37 were negative isolate (37 %). The results indicate isolates recovered were gram-positive and gram-negative bacteria with five bacterial genera isolated consist of 3 Gram-positive and 2 Gram-negative bacteria. The isolates were subjected to sensitivity test of various antibiotics like Ciprofloxacin, Pefloxacin, and Oflaxacinm and they were sensitive, while Chloramphenicol, Ciprofloxacin, Gentamicin, Streptomycin and Oflaxacin were Intermediate and Amoxicillin, Erythromycin, Cotrimoxazole, Gentamycin, and Ceftriaxone were resistance to the antimicrobial sensitivity tests. Pneumonic bacteria isolates based on sex and age of the cattle slaughtered at Maiduguri abattoir were recorded. Bull has the highest 58 (92.0%) compare to the cow 5 (8.0%). While age-wise, Isolates were recorded with highest 97.0 % among adult cattle when compare to the young cattle (3.0%). Three types of pneumonia were identified based on the Pathological examinations of 25 pneumonic lungs randomly selected from the 100 lungs samples which were recorded. [ABSTRACT FROM AUTHOR]

Abstract Pneumonia is a common infection in patients of all ages. Determining its etiology and selecting antibiotic therapy are challenging for physicians in both private practice and hospitals. Moreover, the coronavirus disease pandemic revealed the importance of prevention and treatment of secondary bacterial pneumonia in patients hospitalized with viral respiratory infections. This review focuses on the types of bacteria that cause pneumonia and provides new insights into antibiotic therapy for bacterial pneumonia. Moreover, it also reviews the current state of knowledge regarding secondary bacterial pneumonia.

Neutrophils are the first leukocytes to be recruited to sites of inflammation in response to chemotactic factors released by activated macrophages and pulmonary epithelial and endothelial cells in bacterial pneumonia, a common cause of acute respiratory distress syndrome (ARDS). Although neutrophilic inflammation facilitates the elimination of pathogens, neutrophils also may cause bystander tissue injury. Even though the presence of neutrophils in alveolar spaces is a key feature of acute lung injury and ARDS especially from pneumonia, their contribution to the pathogenesis of lung injury is uncertain. The goal of this study was to elucidate the role of neutrophils in a clinically relevant model of bacterial pneumonia. We investigated the effect of reducing neutrophils in a mouse model of pneumococcal pneumonia treated with antibiotics. Neutrophils were reduced with anti-lymphocyte antigen 6 complex locus G6D (Ly6G) monoclonal antibody 24 h before and immediately preceding infection. Mice were inoculated intranasally with Streptococcus pneumoniae and received ceftriaxone 12 h after bacterial inoculation. Neutrophil reduction in mice treated with ceftriaxone attenuated hypoxemia, alveolar permeability, epithelial injury, pulmonary edema, and inflammatory biomarker release induced by bacterial pneumonia, even though bacterial loads in the distal air spaces of the lung were modestly increased as compared with antibiotic treatment alone. Thus, when appropriate antibiotics are administered, lung injury in the early phase of bacterial pneumonia is mediated in part by neutrophils. In the early phase of bacterial pneumonia, neutrophils contribute to the severity of lung injury, although they also participate in host defense. NEW & NOTEWORTHY: Neutrophil accumulation is a key feature of ARDS, but their contribution to the pathogenesis is still uncertain. We investigated the effect of reducing neutrophils in a clinically relevant mouse model of pneumococcal pneumonia treated with antibiotics. When appropriate antibiotics were administered, neutrophil reduction with Ly6G antibody markedly attenuated lung injury and improved oxygenation. In the early phase of bacterial pneumonia, neutrophils contribute to the severity of lung injury, although they also participate in host defense. [ABSTRACT FROM AUTHOR]

Background-Community-acquired pneumonia (CAP) is a significant health concern in children, leading to high morbidity and mortality worldwide. Lung ultrasound (LUS) is a non-invasive, costeffective, and non-ionizing imaging modality that has the potential to diagnose and monitor CAP, differentiating between bacterial and non-bacterial pneumonia. This study evaluates the role of LUS in the evaluation and monitoring of CAP in the pediatric population. Methods- This prospective observational study was conducted in the Department of Radiodiagnosis at M.G.M. Medical College, Indore, from September 2022 to September 2023. A total of 108 pediatric patients clinically diagnosed with CAP were included. LUS was performed on the day of admission and follow-up scans were conducted between the 5th and 7th day, and between the 10th and 14th day postadmission. Ultrasound findings, such as echo-poor non-aerated lesions, air bronchograms, pleural effusion, B lines, collapse, pleural thickening, and specific vascular patterns, were documented and analyzed. Results - The study included 108 patients aged 1 month to 16 years, with a slight male predominance (50.9%). The most common symptoms were cold (70.37%), cough (69.44%), and fever (59.25%). LUS findings indicated that bacterial CAP often presented with larger, unilateral, and solitary pneumonic lesions with air or fluid bronchograms and pleural effusion. Non-bacterial CAP was characterized by sub-centimetric, multifocal, and bilateral lesions with diffuse B lines and pleural thickening. LUS showed a diagnostic sensitivity of 87% and an accuracy of 85% for identifying the etiology of CAP. Follow-up scans demonstrated significant regression of lesions, particularly in bacterial CAP cases. Conclusion- Lung ultrasound is a highly sensitive and accurate imaging modality for diagnosing, characterizing, and monitoring community-acquired pneumonia in pediatric patients. It effectively differentiates between bacterial and non-bacterial pneumonia, improving diagnostic accuracy and guiding appropriate management. LUS should be included in diagnostic protocols for CAP alongside clinical and laboratory data. [ABSTRACT FROM AUTHOR]

Pulmonary infections contribute substantially to emergency department (ED) visits, posing a considerable health burden. Lower respiratory tract infections are prevalent, particularly among the elderly, constituting a significant percentage of infectious disease-related ED visits. Timely recognition and treatment are crucial to mitigate morbidity and mortality. Imaging studies, primarily chest radiographs and less frequently CT chests, play a pivotal role in diagnosis. This article aims to elucidate the imaging patterns of both common and rare pulmonary infections (bacterial and viral) in the post COVID-19 era, emphasizing the importance of recognizing distinct radiological manifestations. The integration of clinical and microbiological evidence aids in achieving accurate diagnoses, and guiding optimal therapeutic interventions. Despite potential overlapping manifestations, a nuanced understanding of radiological patterns, coupled with comprehensive clinical and microbiological information, enhances diagnostic precision in majority cases. [ABSTRACT FROM AUTHOR]

Pneumonia is a common infection in patients of all ages. Determining its etiology and selecting antibiotic therapy are challenging for physicians in both private practice and hospitals. Moreover, the coronavirus disease pandemic revealed the importance of prevention and treatment of secondary bacterial pneumonia in patients hospitalized with viral respiratory infections. This review focuses on the types of bacteria that cause pneumonia and provides new insights into antibiotic therapy for bacterial pneumonia. Moreover, it also reviews the current state of knowledge regarding secondary bacterial pneumonia. [ABSTRACT FROM AUTHOR]

Background: Bronchoalveolar lavage (BAL) is a widely used diagnostic procedure in pulmonology, yet its utility across diverse pulmonary conditions warrants further evaluation. Methods: This prospective study involved 47 patients suspected of having pulmonary diseases, where conventional diagnostics were inconclusive. BAL was performed to diagnose infections, interstitial lung diseases (ILDs), and malignancies, with subsequent analysis for sensitivity, specificity, and diagnostic yield. Results: BAL identified tuberculosis in 15 cases (31.9%), bacterial pneumonia in 10 (21.3%), fungal infections in 2 (4.3%), ILDs in 5 (10.6%), and malignancies in 6 (12.8%). The procedure demonstrated high diagnostic accuracy with sensitivity and specificity rates notably high across conditions: tuberculosis (88.2%, 97.0%; p<0.001), bacterial pneumonia (76.9%, 98.5%; p<0.001), fungal infections (66.7%, 99.0%; p=0.005), ILDs (83.3%, 96.7%; p=0.001), and malignancies (85.7%, 97.5%; p<0.001). Conclusion: The study highlights BAL's substantial diagnostic value in pulmonary diseases, reinforcing its role in enhancing diagnostic accuracy and informing therapeutic strategies. BAL emerges as an indispensable tool in the early detection and management of complex lung diseases. [ABSTRACT FROM AUTHOR]

The outbreak of the novel corona virus disease (COVID-19) in December 2019 has led to global crisis around the world. The disease was declared pandemic by World Health Organization (WHO) on 11th of March 2020. Currently, the outbreak has affected more than 200 countries with more than 37 million confirmed cases and more than 1 million death tolls as of 10 October 2020. Reverse-transcription polymerase chain reaction (RT-PCR) is the standard method for detection of COVID-19 disease, but it has many challenges such as false positives, low sensitivity, expensive, and requires experts to conduct the test. As the number of cases continue to grow, there is a high need for developing a rapid screening method that is accurate, fast, and cheap. Chest X-ray (CXR) scan images can be considered as an alternative or a confirmatory approach as they are fast to obtain and easily accessible. Though the literature reports a number of approaches to classify CXR images and detect the COVID-19 infections, the majority of these approaches can only recognize two classes (e.g., COVID-19 vs. normal). However, there is a need for well-developed models that can classify a wider range of CXR images belonging to the COVID-19 class itself such as the bacterial pneumonia, the non-COVID-19 viral pneumonia, and the normal CXR scans. The current work proposes the use of a deep learning approach based on pretrained AlexNet model for the classification of COVID-19, non-COVID-19 viral pneumonia, bacterial pneumonia, and normal CXR scans obtained from different public databases. The model was trained to perform two-way classification (i.e., COVID-19 vs. normal, bacterial pneumonia vs. normal, non-COVID-19 viral pneumonia vs. normal, and COVID-19 vs. bacterial pneumonia), three-way classification (i.e., COVID-19 vs. bacterial pneumonia vs. normal), and four-way classification (i.e., COVID-19 vs. bacterial pneumonia vs. non-COVID-19 viral pneumonia vs. normal). For non-COVID-19 viral pneumonia and normal (healthy) CXR images, the proposed model achieved 94.43% accuracy, 98.19% sensitivity, and 95.78% specificity. For bacterial pneumonia and normal CXR images, the model achieved 91.43% accuracy, 91.94% sensitivity, and 100% specificity. For COVID-19 pneumonia and normal CXR images, the model achieved 99.16% accuracy, 97.44% sensitivity, and 100% specificity. For classification CXR images of COVID-19 pneumonia and non-COVID-19 viral pneumonia, the model achieved 99.62% accuracy, 90.63% sensitivity, and 99.89% specificity. For the three-way classification, the model achieved 94.00% accuracy, 91.30% sensitivity, and 84.78%. Finally, for the four-way classification, the model achieved an accuracy of 93.42%, sensitivity of 89.18%, and specificity of 98.92%. [ABSTRACT FROM AUTHOR]

ABSTRACT In vivo imaging of bacterial infection models enables noninvasive and temporal analysis of individuals, enhancing our understanding of infectious disease pathogenesis. Conventional in vivo imaging methods for bacterial infection models involve the insertion of the bacterial luciferase LuxCDABE into the bacterial genome, followed by imaging using an expensive ultrasensitive charge-coupled device (CCD) camera. However, issues such as limited light penetration into the body and lack of versatility have been encountered. We focused on near-infrared (NIR) light, which penetrates the body effectively, and attempted to establish an in vivo imaging method to evaluate the number of lung-colonizing bacteria during the course of bacterial pneumonia. This was achieved by employing a novel versatile system that combines plasmid-expressing firefly luciferase bacteria, NIR substrate, and an inexpensive, scientific complementary metal-oxide semiconductor (sCMOS) camera. The D-luciferin derivative “TokeOni,” capable of emitting NIR bioluminescence, was utilized in a mouse lung infection model of Acinetobacter baumannii, an opportunistic pathogen that causes pneumonia and is a concern due to drug resistance. TokeOni exhibited the highest sensitivity in detecting bacteria colonizing the mouse lungs compared with other detection systems such as LuxCDABE, enabling the monitoring of changes in bacterial numbers over time and the assessment of antimicrobial agent efficacy. Additionally, it was effective in detecting A. baumannii clinical isolates and Klebsiella pneumoniae. The results of this study are expected to be used in the analysis of animal models of infectious diseases for assessing the efficacy of therapeutic agents and understanding disease pathogenesis.IMPORTANCEConventional animal models of infectious diseases have traditionally relied upon average assessments involving numerous individuals, meaning they do not directly reflect changes in the pathology of an individual. Moreover, in recent years, ethical concerns have resulted in the demand to reduce the number of animals used in such models. Although in vivo imaging offers an effective approach for longitudinally evaluating the pathogenesis of infectious diseases in individual animals, a standardized method has not yet been established. To our knowledge, this study is the first to develop a highly versatile in vivo pulmonary bacterial quantification system utilizing near-infrared luminescence, plasmid-mediated expression of firefly luciferase in bacteria, and a scientific complementary metal-oxide semiconductor camera. Our research holds promise as a useful tool for assessing the efficacy of therapeutic drugs and pathogenesis of infectious diseases.

Introduction Postoperative Legionella pneumonia is very rare. Case presentation A 71‐year‐old male patient with prostate cancer (cT2bN0M0) underwent a robotic‐assisted radical prostatectomy. On the 5th postoperative day, the patient developed chills and a fever of 39.2°C. Chest radiography revealed decreased permeability in the right middle lung field, leading to the diagnosis of postoperative pneumonia. Antimicrobial therapy was initiated immediately. Blood tests on postoperative day 10 revealed mild liver function abnormalities, electrolyte abnormalities, and a markedly elevated inflammatory response. Legionella pneumonia was suspected based on blood sample results and systemic symptoms, such as diarrhea and nausea. Furthermore, Legionella antigens were detected in the patient's urine, prompting further administration of levofloxacin. The patient's subsequent clinical course was favorable. Conclusion When bacterial pneumonia fails to respond to antimicrobial therapy and systemic symptoms develop, atypical pneumonia, caused by pathogens such as Legionella pneumophila, should be considered even in cases of postoperative pneumonia.

Lu Lv,1,2 Xinyue Shao,1,3 Enhai Cui1 1Department of Respiratory and Critical Care Medicine, Huzhou Central Hospital, Affiliated Huzhou Hospital, Zhejiang University School of Medicine, Huzhou, Zhejiang, People’s Republic of China; 2Department of Respiratory and Critical Care Medicine, Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang, People’s Republic of China; 3School of Medicine, Huzhou University, Huzhou, Zhejiang, People’s Republic of ChinaCorrespondence: Enhai Cui, Department of Respiratory and Critical Care Medicine, Huzhou Central Hospital, Affiliated Huzhou Hospital, Zhejiang University School of Medicine, Huzhou, Zhejiang, People’s Republic of China, Tel +86 13857281688, Fax +86 572-2023219, Email kjkceh@126.comBackground: Community-acquired pneumonia (CAP) is a global health concern due to its high rates of morbidity and mortality. Bacterial pathogens are common causes of CAP. It is one of the most common causes of acute respiratory distress syndrome (ARDS), a common severe respiratory system manifestation threatening human health. This study aimed to establish a predictive model for ARDS in patients with bacterial pneumonia, which was conducive to early identification of the occurrence and effective prevention of ARDS.Methods: We collected the clinical data of hospitalized patients with bacterial pneumonia in Affiliated Huzhou Hospital of Zhejiang University School of Medicine from January 2022 to November 2022. The independent risk factors for ARDS in patients with bacterial pneumonia were determined by univariate and multivariate binary logistic regression analyses. The nomogram was constructed to display the predictive model, and the receiver-operating characteristic curve was plotted to evaluate the predictive value of ARDS.Results: This study included 254 patients with bacterial pneumonia, of which 114 developed ARDS. The multivariate logistic regression analysis revealed age [odds ratio (OR) = 1.041, P = 0.003], heart rate (OR = 1.020, P = 0.028), lymphocyte count (OR = 0.555, P = 0.033), white blood cell count (OR = 1.062, P = 0.033), bilateral lung lesions (OR = 7.352, P = 0.011) and pleural effusion (OR = 2.512, P = 0.002) as the independent risk factors for ARDS. The predictive model was constructed based on the six independent factors, which was valuable in predicting ARDS with area under the curve of 0.794.Conclusion: The predictive model was beneficial to evaluate the disease progression in patients with bacterial pneumonia and identify ARDS. Further, our nomogram might help doctors predict the incidence of ARDS and conduct treatment as early as possible.Keywords: acute respiratory distress syndrome, bacterial pneumonia, nomogram, retrospective study, risk factors

Abstract Background Bacterial pneumonia can affect all age groups, but people with weakened immune systems, young children, and the elderly are at a higher risk. Streptococcus pneumoniae, Klebsiella pneumoniae, Haemophilus influenzae, and Pseudomonas aeruginosa are the most common causative agents of pneumonia, and they have developed high MDR in recent decades in Ethiopia. This systematic review and meta-analysis aimed to determine the pooled prevalence of bacterial pneumonia and multidrug resistance in Ethiopia. Methods The articles were searched extensively in the electronic databases and grey literature using entry terms or phrases. Studies meeting the eligibility criteria were extracted in MS Excel and exported for statistical analysis into STATA version 14 software. The pooled prevalence of bacterial pneumonia and multidrug resistance were calculated using a random-effects model. Heterogeneity was assessed by using the I2 value. Publication bias was assessed using a funnel plot and Egger’s test. A sensitivity analysis was done to assess the impact of a single study on the pooled effect size. Result Of the 651 studies identified, 87 were eligible for qualitative analysis, of which 11 were included in the meta-analysis consisting of 1154 isolates. The individual studies reported prevalence of bacterial pneumonia ranging from 6.19 to 46.3%. In this systematic review and metanalysis, the pooled prevalence of bacterial pneumonia in Ethiopia was 37.17% (95% CI 25.72–46.62), with substantial heterogeneity (I2 = 98.4%, p