Mycoplasma pneumoniae (MP) is a key cause of community-acquired pneumonia, and coinfections lead to varied patient outcomes. A comprehensive understanding of the outcome characteristics and associated etiologies of coinfections in MP patients is lacking.

We analyzed 121,357 MP cases from 522,292,680 visits in Wuhan, China, in 2023 (the final year of the COVID-19 pandemic). Children aged 1-10 years had the highest incidence, whereas those over 60 years had elevated hospitalization, severe infection, and fatality rates. Coinfection patterns differed by age, with bacterial-viral-Chlamydia pneumoniae (C. pneumoniae) / other pathogens prevalent in infants, bacterial-viral pathogens prevalent in preschoolers, and viral-viral pathogens prevalent in school-aged children. Bacterial coinfections were most common in MP-infected patients, especially those who were hospitalized. Coinfection, especially with C. pneumoniae, Pseudomonas aeruginosa (P. aeruginosa), Haemophilus influenzae (H. influenzae), and Streptococcus pneumoniae (S. pneumoniae), increased hospitalization rates. The most severe outcomes and deaths occurred in patients coinfected with C. pneumoniae-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza A-parainfluenza virus (PIV) or adenovirus-PIV. Logistic regression analysis demonstrated that male sex and adult age (particularly ≥40 years) were significantly associated with adverse outcomes in MP monoinfection. For coinfections, significantly higher hospitalization rates were reported among very young children (0-5 years) and adults aged ≥40 years, whereas adults presented an increased risk of severe disease. Coinfection outcomes were significantly associated with seasons of the year (winter, spring, and summer), specific age groups (3-5 years, 18-39 years, 40-50 years, and 60 years and over), gender (male), and longer onset-to-diagnosis periods. Middle-aged and elderly patients, coinfection, spring and summer, gender (male), and longer onset-to-diagnosis periods were significantly associated with increased hospitalization and serious illness risk. Coinfection, winter, older (adult) age, and gender (male) were significantly associated with an increased risk of death.

Compared with adults, children with MP have a greater morbidity risk, whereas middle-aged and older adults face greater risks of hospitalization, serious illness, and death. Coinfection with other pathogens heightens hospitalization and death risks. These insights are crucial for etiological screening, diagnosing multiple pathogens, and preventing and treating infections.

Ceftriaxone is widely used for hospitalized patients with community-acquired pneumonia, but its optimal dosage remains unclear.

We retrospectively identified patients diagnosed with pneumonia between July 2010 and March 2022 from the Diagnosis Procedure Combination inpatient database in Japan. They were categorized into those receiving 2 or 1 g/day of ceftriaxone within the first 2 days of hospitalization. The primary outcome was 30-day in-hospital mortality. The secondary outcomes included overall adverse events (composite of biliary tract infection, Clostridioides difficile infection and allergic reactions) and each adverse event. A subgroup analysis was conducted for patients requiring mechanical ventilation. Propensity-score overlap-weighting analysis was used for comparisons.

Among the 471 694 eligible patients, 63.3% received 2 g/day and 36.7% received 1 g/day of ceftriaxone. Propensity-score analysis showed no significant difference in 30-day in-hospital mortality between the two groups [4.5% versus 4.6%; risk difference (RD), -0.1%; 95% confidence interval (CI), -0.3% to 0.1%; P = 0.219]. Overall adverse events were slightly higher in the 2 g/day group (1.9% versus 1.8%; RD, 0.1%; 95% CI, 0.0%-0.2%; P = 0.007), particularly the proportion of C. difficile infection. In the subgroup analysis of patients requiring mechanical ventilation, the 2 g/day regimen was associated with lower 30-day mortality (17.2% versus 20.4%; RD, -3.2%; 95% CI, -5.6% to -0.9%; P = 0.006).

While a ceftriaxone dose exceeding 1 g/day may not be necessary for routine pneumonia treatment, a 2 g/day regimen may be considered for patients with severe pneumonia requiring mechanical ventilation.

Aspiration pneumonia presents a significant healthcare challenge, particularly in aging societies. Despite extensive research, a comprehensive bibliometric analysis of this field has not been previously conducted. This study aimed to systematically analyze the publication patterns, research collaborations, and thematic trends in aspiration pneumonia research between 1980 and 2024.

We conducted a bibliometric analysis using data from the Web of Science Core Collection database. The analysis included publication trends, citation patterns, author productivity, and research categories. Network analyses were performed using VOSviewer to visualize international collaborations, author networks, and keyword co-occurrence patterns.

Our analysis of 4668 publications revealed a substantial growth in research output, from 10 publications in 1980 to 371 in 2023. The United States and Japan emerged as the 2 major centers of research output. Analysis of the research categories showed a shift from surgical perspectives during the earlier periods toward more comprehensive medical management approaches in recent years, with General Internal Medicine becoming the leading category between 2010 and 2024. The author collaboration network revealed geographically distinct research clusters with limited cross-regional interactions. Keyword co-occurrence analysis identified 4 major research domains: clinical and epidemiological aspects (41 items), treatment-related approaches (29 items), neurological and swallowing disorders (29 items), and malnutrition.

Our findings demonstrate the evolution of aspiration pneumonia research toward an increasingly multifaceted field that integrates clinical care, rehabilitation, and preventive strategies. The distinct regional patterns in research output suggest opportunities for enhanced international collaboration to advance the current understanding of this condition.

Hospitalized community-acquired pneumonia (CAP) patients are admitted for ventilation, vasopressors, and renal replacement therapy (RRT). This study aimed to develop a machine learning (ML) model that predicts the need for such interventions and compare its accuracy to that of logistic regression (LR).

This retrospective observational study trained separate models using random-forest classifier (RFC), support vector machines (SVMs), Extreme Gradient Boosting (XGBoost), and multilayer perceptron (MLP) to predict three endpoints: eventual use of invasive ventilation, vasopressors, and RRT during hospitalization. RFC-based models were overall most accurate in a derivation COVID-19 CAP cohort and were validated in one COVID-19 CAP and two non-COVID-19 CAP cohorts.

This study is part of the Community-Acquired Pneumonia: Toward InnoVAtive Treatment (CAPTIVATE) Research program.

Two thousand four hundred twenty COVID-19 and 1909 non-COVID-19 CAP patients over 18 years old hospitalized and not needing invasive ventilation, vasopressors, and RRT on the day of admission were included.

None.

Performance was evaluated with area under the receiver operating characteristic curve (AUROC) and accuracy. RFCs performed better than XGBoost, SVM, and MLP models. For comparison, we evaluated LR models in the same cohorts. AUROC was very high ranging from 0.74 to 0.95 in predicting ventilation, vasopressors, and RRT use in our derivation and validation cohorts. ML used and variables such as Fio2, Glasgow Coma Scale, and mean arterial pressure to predict ventilator, vasopressor use, creatinine, and potassium to predict RRT use. LR was less accurate than ML, with AUROC ranging 0.66 to 0.8.

A ML algorithm more accurately predicts need of invasive ventilation, vasopressors, or RRT in hospitalized non-COVID-19 CAP and COVID-19 patients than regression models and could augment clinician judgment for triage and care of hospitalized CAP patients.

Ampicillin/sulbactam, a combination of a β-lactam and β-lactamase inhibitor, is widely used in clinical settings. However, therapeutic drug monitoring (TDM) of ampicillin is not commonly performed, particularly in intensive care units (ICUs). The purpose of this study was to develop and validate a rapid and cost-effective high-performance liquid chromatography (HPLC)-ultraviolet spectrometry method to quantify ampicillin in human serum and evaluate its clinical application in ICU patients.

Sample cleanup included a protein precipitation protocol, followed by chromatographic separation on a C18 reverse-phase HPLC column within 12.5 minutes using gradient elution of the mobile phase. The assay was validated according to the German Society of Toxicology and Forensic Chemistry criteria. Clinical applications involved the retrospective analysis of TDM data from ICU patients receiving continuous infusion of ampicillin/sulbactam, including the attainment of target ranges and individual predicted and observed pharmacokinetics.

The method was robust, with linear relations between the peak area responses and drug concentrations in the range of 2-128 mg/L. The coefficient of variation for precision and the bias for accuracy (both interday and intraday) were less than 10%. Clinical application revealed variable pharmacokinetics of ampicillin in ICU patients (clearance of 0.5-31.2 L/h). TDM-guided dose adjustments achieved good therapeutic drug exposure, with 92.9% of the samples being within the optimal (16-32 mg/L) or quasioptimal (8-48 mg/L) range.

This method provides a practical solution for the routine TDM of ampicillin, facilitating individualized dosing strategies to ensure adequate therapeutic drug exposure. Given its simplicity, cost-effectiveness, and clinical relevance, HPLC-ultraviolet spectrometry holds promise for broad implementation in hospital pharmacies and clinical laboratories.

Studies suggest that clarithromycin is associated with an increased risk of major adverse cardiovascular events (MACE) among adults with coronary artery disease. However, data comparing clarithromycin to other macrolides, such as azithromycin, in a broader population are lacking.

A multicenter study was conducted in 33 hospitals in Ontario, Canada, and Copenhagen, Denmark, using the Target Trial framework. Adults hospitalized with community-acquired pneumonia (CAP) who received either clarithromycin or azithromycin were included. The primary outcome was MACE, defined as the one-year risk of nonfatal myocardial infarction, nonfatal stroke, or all-cause mortality. Propensity score matching and Cox proportional hazards models were used for analysis.

In Ontario, we identified 23 081 patients with CAP, and 11 164 received oral macrolides. After propensity score matching, the primary outcome occurred in 7.8% of clarithromycin patients and 9.1% of azithromycin patients (HR 0.85, 95% CI 0.60-1.21). In Copenhagen, there were 11 280 patients with CAP and 3924 received oral macrolides. After propensity score matching, 19% of clarithromycin patients and 12% of azithromycin patients experienced the primary outcome for oral macrolides (HR 1.7, 95% CI 1.2-2.4, p = 0.002). Meta-analysis of the point estimate from each country provided an overall HR of 1.21 (95% CI 0.61-2.39). For intravenous macrolides in Copenhagen, the HR was 1.15 (95% CI 1.0-1.3, p = 0.007) for clarithromycin compared to azithromycin.

This study did not consistently observe an increased risk of cardiovascular events with clarithromycin among adults hospitalized with CAP. However, the observational nature of the study may introduce selection bias and unmeasured confounding.

Ceftriaxone is believed to increase the risk of biliary infections due to pseudolithiasis caused by ceftriaxone-calcium precipitation, but this risk is not well understood. This study aimed to investigate whether ceftriaxone use is associated with an increased risk of biliary infections in pneumonia patients using a national inpatient database.

We analyzed the Diagnosis Procedure Combination database in Japan, identifying pneumonia patients between July 2010 and March 2022. Patients were grouped by treatment: ceftriaxone versus ampicillin-sulbactam or cefotaxime. Propensity score overlap-weighting was used to adjust for confounding factors. The primary outcome was a composite measure, including cholecystitis or cholangitis during hospitalization, and any percutaneous, endoscopic, or surgical interventions on the biliary tract. Secondary outcomes included individual components of the primary outcome.

Of the 1 503 885 eligible patients, 558 725 received ceftriaxone, while 945 160 were treated with either ampicillin-sulbactam or cefotaxime. The mean dose of ceftriaxone was 1.7 g/day (standard deviation, 0.7 g/day), with a mean administration duration of 7.1 days (standard deviation, 3.8 days). Propensity score overlap-weighting analysis revealed that ceftriaxone treatment was associated with an increased incidence of the composite outcome (0.22% vs. 0.18%; risk difference, 0.05%; 95% confidence interval, 0.03%-0.07%; p < 0.001), as well as the secondary outcomes, including cholecystitis or cholangitis during hospitalization and percutaneous or endoscopic drainage of the gallbladder or biliary tract.

Ceftriaxone use was associated with a slight increase in the risk of biliary infections.

Background: The 2019 Center for Disease Control and Prevention's Core Elements of Hospital Antibiotic Stewardship identifies community-acquired pneumonia (CAP) as a crucial area for improving antibiotic use. Transitions of care (TOC) pharmacists can optimize medication therapy for CAP patients. Methods: This was a retrospective, multi-hospital analysis of discharge antibiotic prescribing. Between December 1, 2022, and June 30, 2023, TOC pharmacists intervened to decrease discharge days of therapy (DOT) for CAP therapy. The study compared records of CAP patients with a TOC antibiotic stewardship intervention vs those without. An additional three-group analysis compared patients without an intervention to those with an accepted intervention to those with a rejected intervention. Results: 196 patient records were included in the analysis; 80 had a TOC pharmacist intervention and 116 did not. 62 interventions were accepted and 18 were rejected. Mean final discharge DOT was 3.8 ± 1.7 days in the non-intervention group and 3.4 ± 1.6 days in the intervention group (P = 0.231). Mean total DOT was 6.8 ± 2.3 days and 6.8 ± 1.8 days, respectively (P = 0.963). The percentage of patients with appropriate total DOT was 59.5% and 66.3%, respectively (P = 0.337). In the three-group analysis, mean final discharge DOT was 2.9 ± 1.7 days in the accepted group and 4.2 ± 0.9 days in the rejected group (P = 0.030). Mean total DOT was 6.4 ± 1.6 days and 8.1 ± 1.8 days, respectively (P = 0.009). The percentage of patients with appropriate total DOT was 82.3% and 11.1%, respectively (P < 0.001). Conclusion: The accepted TOC pharmacist interventions significantly reduced both discharge DOT and total DOT. These findings emphasize the impact TOC pharmacists can have with antimicrobial stewardship initiatives.

Psittacosis is a globally underappreciated and frequently undiagnosed zoonotic disease, and it is often difficult to determine the number of individuals exposed to Chlamydia psittaci. Despite numerous reported cases and outbreaks worldwide, there has been no systematic assessment of psittacosis prevalence to date, which is crucial for evaluating the disease burden and developing vaccines. Our objective is to evaluate the global prevalence of psittacosis in outbreaks.

We conducted a comprehensive search across multiple databases, including PubMed, Web of Science, Cochrane Library, and Medline, from the date of establishment to May 15, 2024. Additionally, we manually searched reference lists of included articles and retrieved reviews to identify any supplementary articles. The primary summary data was the prevalence of psittacosis in the outbreaks. Pooled estimates of prevalence were calculated for both the entire population and subgroups using a random-effects model.

Thirty-one eligible studies from 13 countries across four continents were included in this review. The pooled prevalence of psittacosis among 4,158 exposed individuals in outbreaks was 27.7% (95% CI: 20.9-34.9). Meta-regression analysis of six potential influencing factors (geographic region, outbreak sites, outbreak season, infectious source, publication year, and study quality) indicated that the source of heterogeneity may be associated with the outbreak sites (P = 0.031). Furthermore, among the cases collected, the hospitalization rate was 42.3% (95% CI: 24.7-60.8), the prevalence of pneumonia was 59.7% (95% CI: 41.4-76.9), and the fatality rate was 1.8% (95% CI: 0-6.9).

The global prevalence of psittacosis in outbreaks was found to be 27.7%, with a hospitalization rate of 42.3%, a pneumonia rate of 59.7%, and a mortality rate of 1.8%. Such knowledge will assist governmental and medical authorities in formulating public health policies for populations at high risk of bird exposure, assessing the disease burden, and developing effective vaccines.

Lefamulin is a novel pleuromutilin antibiotic used for the treatment of community-acquired pneumonia (CAP). This study aimed to evaluate the in vitro antimicrobial activity of lefamulin against clinical isolates obtained from China.

1,052 non-duplicate isolates included the following isolates: Streptococcus pneumoniae (n = 529), Staphylococcus aureus (n = 306), Haemophilus influenzae (n = 121), Moraxella catarrhalis (n = 81), and Mycoplasma pneumoniae (n = 15), were collected from 70 hospitals participating in the China Antimicrobial Surveillance Network (CHINET) between October 1, 2020, and November 30, 2022. Minimum inhibitory concentrations were determined using the broth microdilution method in accordance with the standards set by the Clinical and Laboratory Standards Institute.

In vitro, S. pneumoniae exhibited 100% sensitivity to lefamulin, with MIC90 values of 0.125 µg/mL for penicillin-susceptible strains, 0.25 µg/mL for penicillin-intermediate strains, and 0.125 µg/mL for penicillin-resistant strains. Lefamulin remained effective against S. pneumoniae strains resistant to penicillin, erythromycin, and azithromycin. The susceptibility rate of S. aureus to lefamulin was 97.7%, with methicillin-sensitive S. aureus showing 98.4% sensitivity and methicillin-resistant S. aureus showing 96.6% sensitivity. Both strains had MIC90 values of 0.125 µg/mL. H. influenzae and M. catarrhalis demonstrated 100% sensitivity to lefamulin. The MIC of lefamulin against M. pneumoniae was ≤ 0.03 µg/mL.

Lefamulin exhibited potent in vitro activity against prevalent and drug-resistant pathogens associated with CAP in China.

Current severity scoring systems (PSI and CURB-65) have limitations in risk stratification for elderly patients with community-acquired pneumonia (CAP). Given the complex immune responses in elderly populations, dynamic biomarker monitoring may provide additional prognostic value. This study evaluates whether integrating early cytokine dynamics with traditional severity scores improves mortality prediction in elderly CAP patients. This prospective observational study included 81 CAP patients aged ≥ 65 years. Multiple cytokines were measured at admission and within 48 h. Traditional severity scores (PSI and CURB-65) were calculated at baseline. Patients were categorized into survival (n = 67) and mortality (n = 14) groups. The predictive value of cytokine dynamics alone and in combination with severity scores was assessed using ROC curve analysis. Among measured cytokines, IL-6 demonstrated significant prognostic value. The mortality group showed an 88% increase in IL-6 levels within 48 h, contrasting with a 49% decrease in survivors (p = 0.040). While individual PSI (AUC = 0.6631) and CURB-65 (AUC = 0.6231) showed modest discrimination, integration with IL-6 dynamics significantly improved predictive accuracy (PSI + IL-6: AUC = 0.7676, p = 0.0017; CURB-65 + IL-6: AUC = 0.7564, p = 0.0027). Early dynamic monitoring of cytokines, particularly IL-6, significantly enhances the prognostic accuracy of traditional severity scores in elderly CAP patients. This pilot study suggests that this integrated approach provides a more precise risk stratification tool, potentially enabling more personalized clinical decision-making. Larger multicenter studies are warranted to validate these findings and establish standardized cutoff values for clinical implementation.

Pneumonia is a frequent cause of intensive care unit (ICU) admission and is the most common infection in ICU patients across all geographic regions. It takes 48-72h for most patients to respond to appropriate antibiotic therapy. Non-response is typically defined as the persistence/worsening of clinical signs-such as fever, respiratory distress, impaired oxygenation and/or radiographic abnormalities-with rates ranging 20-30%. Several factors can contribute to non-response. Host factors, including immunosuppression, chronic lung disease, or ongoing aspiration, may impair resolution. Additionally, incorrect antibiotic dosing, atypical or resistant pathogens (such as multidrug-resistant bacteria, Mycobacterium tuberculosis, or fungal infections) may be responsible, requiring alternative antimicrobial strategies. A septic complication related to pneumonia (e.g., empyema) or not (e.g., acalculous cholecystitis) may need to be excluded. Finally, non-infectious conditions (e.g., pulmonary embolism, malignancy, secondary ARDS or vasculitis) that can mimic or potentiate pneumonia must be considered. Although non-responding pneumonia is frequent, its management lacks strong evidence, and its approach is based mostly on the art of medicine and clinical judgement. Clinicians should continuously reassess the medical history and physical exam, review microbiological data, and consider imaging such as chest CT. Bronchoscopy or repeat sputum sampling may aid in identifying alternative pathogens or non-infectious causes. The management of a non-responding pneumonia depends on the findings of a structured reassessment. Herein, we provide guidance on how to identify and manage non-responding pneumonia. Ultimately, addressing pneumonia that does not respond to antibiotics is crucial for preventing complications, optimizing antimicrobial stewardship, and improving patient outcomes.

Pneumonia may be caused by a diverse group of microorganisms; however, a microbiologic diagnosis is not universally made. Molecular tests such as the BIOFIRE FILMARRAY Pneumonia Panel (BF-PP) offer the possibility of rapid identification of potential pneumonia pathogens. This retrospective analysis was conducted as a sub-study of a recently published randomized controlled trial. Specimens from patients with suspected pneumonia were tested by the BF-PP, with results compared to cultures. The overall BF-PP positivity rate was 44.8% (252/563), and was higher [64.6% (164/254)] in specimens from patients ultimately diagnosed with pneumonia. Discrepancies between the BF-PP and cultures were most common for Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis, and Streptococcus agalactiae. Positive percent agreement (PPA) and negative percent agreement (NPA) between the BF-PP and culture were 91.4% (CI 86.3%-94.9%) and 83.6% (CI 79.5%-87.2%), respectively. For most bacteria, a correlation between high genomic abundance (genomic copies/mL) reported from the BF-PP and culture growth abundance was found. In specimens from patients ultimately diagnosed with pneumonia, clinical consistency-assessed based on whether BF-PP results aligned with associated culture results-was 79.9% and was highest for bronchoalveolar lavage fluid specimens. The BF-PP has reliable analytical performance and offers the potential advantage over conventional cultures of providing higher detection rates and more rapid results. Interestingly, despite the use of this advanced molecular diagnostic tool, one-third of pneumonia cases remained without a microbiologic etiology.IMPORTANCEThis study evaluates the BIOFIRE FILMARRAY Pneumonia Panel by comparing its performance to conventional cultures in a real-world patient population (including patients ultimately diagnosed as not having pneumonia) using different types of specimens. Findings show a higher detection rate of microorganisms with the panel compared to cultures, suggesting that this test could aid in tailoring treatments for pneumonia. However, challenges remain and require further study, including distinguishing true pathogens from colonizing microorganisms and determinig why one-third of patients diagnosed with pneumonia still lacked a microbiologic etiology.

Various risk stratification scores are used to predict outcomes among patients with pneumonia. We have developed a novel model that predicts the risk of death or intensive care unit transfer in internal medicine.

To compare the ability of two prediction models to predict clinical outcomes in patients admitted for pneumonia, using information available at the time of admission.

Comparison of two prediction models.

3856 pneumonia admissions to the internal medicine service of a tertiary medical center.

We compared the ability of two scores to predict in-hospital mortality and escalation of care (e.g., to the intensive care unit) among patients admitted for pneumonia. One was the CURB-65 score, which is currently in use at our hospital. The other score was one we developed, based on the Elixhauser case mix adjustment model with additional data, such as vital signs and laboratory values.

11.8% of patients died in-hospital and 17.7% required an escalation of care. The most common CURB-65 score was 2 (44%), the lowest CURB-65 score ordinarily requiring admission. Our risk prediction score was better than CURB-65 at predicting mortality (c-statistic 0.846 vs. 0.724) and escalation (0.757 vs. 0.633). Our score was able to discriminate among patients classified as similar-risk by the CURB-65 score: of the 1681 patients with a (medium-risk) CURB-65 score of 2, our model placed 180 (11%) into the lowest-risk quintile of patients, and 309 (18%) into the highest-risk quintile.

Our risk stratification tool is calculable with information available in the electronic medical record of most hospitals. The new score was much better able to predict the outcomes of in-hospital mortality and escalation of care among patients admitted for pneumonia, compared to CURB-65.

The purpose of this study was to compare the length of stay (LOS) and costs of diagnostic workup by Ultra Low Dose (ULD) chest computed tomography and radiography for patients treated for a community-acquired pneumonia (CAP) in the emergency department (ED).

We conducted a real-life retrospective study of patients treated for a CAP in two ED between March 1, 2019 and February 29, 2020. We estimated length of stay (LOS) as the difference between ED discharge and entry times, total hospital costs at 60 days including ED, initial admissions and readmissions. Patients with initial radiography were compared with patients with initial ULD CT using inverse probability weighing of the propensity score calculated from demographic variables, vital parameters and clinical presentation. We calculated the incremental cost effectiveness ratio as the difference between costs and the difference between LOS. Variability of the results was assessed using non-parametric bootstrapping.

We included 1609 consecutive patients, 1476 patients with radiography and 133 patients with ULD CT. The average costs were respectively €4317 [3483; 5067] and €4223 [4034; 4612] with 11.9 [10.1; 13.2] and 11.7 [11.5; 12.2] hours of LOS in the ED for chest radiography and ULD chest CT respectively, resulting in lower costs of € -94 [-870; 819] and a decreased LOS of 12 [-108; 76.9] minutes in favor of ULD chest CT.

In this real-life study, the management of CAP in ED by ULD chest CT compared with chest radiography resulted in lower costs without increasing LOS.

This study was registered with the Clinical Trials Registry (NCT05140408).

Severe community-acquired pneumonia (SCAP) remains a leading cause of morbidity and mortality worldwide. Identifying the optimal antibiotic regimen for treating SCAP is crucial for improving patient outcomes.

We searched the PubMed, Embase, and Cochrane Central Register of Controlled Clinical Trials databases to identify studies reporting initial empirical antibiotic regimens in patients with SCAP. We performed a network meta-analysis to compare the relative efficacy of different antibiotic regimens in treating SCAP. The primary outcome was overall mortality. The second outcomes were 30-day mortality and in-hospital mortality.

This network meta-analysis included 1 randomized clinical trial and 13 observational studies with 8142 patients, categorized into five treatment groups: β-lactam antibiotics, β-lactam antibiotics plus doxycycline, β-lactam antibiotics plus fluoroquinolones, β-lactam antibiotics plus macrolides, and fluoroquinolones monotherapy. β-lactam antibiotics plus macrolides was ranked as the most effective treatment (surface under the cumulative ranking curve, 92.0%; mean rank, 1.3). The β-lactam antibiotics plus macrolides combination significantly reduced overall mortality compared to β-lactam antibiotics alone (RR, 0.79; 95% CI, 0.64-0.96) and β-lactam antibiotics plus fluoroquinolones (RR, 0.67; 95% CI, 0.64-0.82).

Our findings suggest that β-lactam antibiotics plus macrolides may be the optimal treatment for SCAP. β-lactam antibiotics monotherapy and β-lactam antibiotics plus fluoroquinolones should not be recommended due to their inferior outcomes.

Severe community-acquired pneumonia (sCAP) is a major global health challenge, with high morbidity and mortality, especially among patients requiring intensive care. Despite advancements in antimicrobial therapies and supportive care, sCAP remains a significant threat, particularly for those needing invasive mechanical ventilation or vasopressor support. Recent progress in diagnostics, therapeutics and management strategies offers hope for improved outcomes. Pathogen-specific management is now central to sCAP care, with molecular diagnostics enhancing pathogen detection accuracy and enabling tailored antimicrobial therapy. These tools help combat antimicrobial resistance by reducing unnecessary broad-spectrum antibiotic use.Host immune responses in sCAP vary widely and significantly impact outcomes. Some patients face an overwhelming pathogen burden, while others experience excessive immune responses, such as acute respiratory distress syndrome. This distinction is vital for guiding immunomodulatory therapies, as immunosuppression may benefit hyperinflammatory states but harm those overwhelmed by infection. Corticosteroids, though controversial, show potential benefits in select populations but carry risks like secondary infections and hyperglycaemia, requiring a nuanced approach.Non-invasive respiratory support strategies, such as high-flow nasal oxygen, have transformed care by improving oxygenation and reducing the need for invasive ventilation. However, their efficacy depends on timing, patient tolerance and disease severity, necessitating careful monitoring.Global disparities in sCAP management, particularly in low-income and middle-income countries, highlight the need for region-specific guidelines and scalable solutions. Limited access to advanced diagnostics and critical care resources exacerbates poor outcomes, underscoring the importance of investments in affordable diagnostics, infection control and multidisciplinary training. Emerging technologies, such as artificial intelligence and advanced imaging, promise to revolutionise sCAP management by enabling precision medicine and real-time insights into disease severity. A holistic, multidisciplinary approach integrating these advancements is essential to improving outcomes and advancing personalised care for this life-threatening condition.

Pneumonia is a major threat to the health of children, especially those under the age of five. Mycoplasma  pneumoniae infection is a core cause of pediatric pneumonia, and the incidence of severe mycoplasma pneumoniae pneumonia (SMPP) has increased in recent years. Therefore, there is an urgent need to establish an early warning model for SMPP to improve the prognosis of pediatric pneumonia.

The study comprised 597 SMPP patients aged between 1 month and 18 years. Clinical data were selected through Lasso regression analysis, followed by the application of eight machine learning algorithms to develop early warning model. The accuracy of the model was assessed using validation and prospective cohort. To facilitate clinical assessment, the study simplified the indicators and constructed visualized simplified model. The clinical applicability of the model was evaluated by DCA and CIC curve.

After variable selection, eight machine learning models were developed using age, sex and 21 serum indicators identified as predictive factors for SMPP. A Light Gradient Boosting Machine (LightGBM) model demonstrated strong performance, achieving AUC of 0.92 for prospective validation. The SHAP analysis was utilized to screen advantageous variables, which contains of serum S100A8/A9, tracheal computed tomography (CT), retinol-binding protein(RBP), platelet larger cell ratio(P-LCR) and CD4+CD25+Treg cell counts, for constructing a simplified model (SCRPT) to improve clinical applicability. The SCRPT diagnostic model exhibited favorable diagnostic efficacy (AUC > 0.8). Additionally, the study found that S100A8/A9 outperformed clinical inflammatory markers can also differentiate the severity of MPP.

The SCRPT model consisting of five dominant variables (S100A8/A9, CT, RBP, PLCR and Treg cell) screened based on eight machine learning is expected to be a tool for early diagnosis of SMPP. S100A8/A9 can also be used as a biomarker for validity differentiation of SMPP when medical conditions are limited.

Previous studies have shown that the lactate/albumin ratio (LAR) can be a prognostic biomarker in intensive care unit (ICU) patients. However, the usefulness of LAR in predicting mortality and guiding intensive care unit admission in hospitalized patients due to community-acquired pneumonia (CAP) remains unclear. This study aims to evaluate the predictive value of the LAR compared to Pneumonia Severity Index (PSI), Confusion, urea, respiratory rate, blood pressure, 65 years or older (CURB-65), and quick-Sequential Organ Failure Assessment (q-SOFA) scores in determining the need for ICU admission and mortality among hospitalized patients with CAP.

Adult patients diagnosed and hospitalized with community-acquired pneumonia between July 2021 and July 2023 were included. Patients' demographics, comorbidities, disease severity scores, laboratory findings at the admission and outcomes were recorded. Patients were grouped and compared according to admission place (ward or ICU).

PSI, CURB-65, q-SOFA scores, and LAR were higher in ICU patients than in those admitted to the ward. Regarding the ICU admission, the AUC values for PSI, CURB-65, q-SOFA and LAR were 0.794 (95% CI: 0.737-0.843) (p < 0.001), 0.825 (95% CI: 0.771-0.870) (p < 0.001), 0.755 (0.690-0.813) (p < 0.001), and 0.749 (95% CI: 0.689-0.802) (p < 0.001), respectively. Regarding the mortality, the AUC values for PSI, CURB-65, q-SOFA, and LAR were 0.722 (95% CI: 0.661-0.778) (p < 0.001), 0.743 (95% CI: 0.683-0.797) (p < 0.001), 0.645 (0.575-0.711) (p: 0.02), 0.761 (95% CI: 0.702-0.814) (p < 0.001), respectively. There wasn't any difference detected in pairwise comparisons of ROC curves.

In this study, LAR was found to be a good predictor of ICU admissions and mortality in hospitalized patients with CAP and was non-inferior to PSI, CURB-65, or q-SOFA scores.

The use of fluoroquinolone (FQ) combination therapy as empirical treatment for severe community-acquired pneumonia (sCAP) remains unclear. In this study, we aimed to evaluate its clinical impact.

This retrospective study was conducted in seven large university-affiliated hospitals in Korea. It included adult inpatients (age ≥19 years) diagnosed with sCAP between March 2020 and February 2023, identified through third-ranked pneumonia codes, who received anti-pseudomonal beta-lactam (APBL) and/or FQ within 24 h of admission. Propensity-score matching compared monotherapy and combination therapy outcomes.

Of 588 enrolled patients with sCAP, 177 per group were analyzed post-matching. No significant differences were found in all-cause in-hospital mortality (36.7 % vs. 36.2 %, P = 0.917), in-hospital mortality from pneumonia aggravation (29.9 % vs. 30.5 %, P = 1.000), or 30-day mortality (26.6 % vs. 29.4 %, P = 0.251). FQ combination therapy did not affect 30-day mortality significantly (P = 0.489). None of the variables significantly influenced 30-day mortality, pneumonia recurrence within 28 days, total antibiotic duration, or hospital stay.

In patients with sCAP, outcomes did not differ significantly between APBL monotherapy and FQ combination therapy. This suggests that even in severe CAP, an individualized treatment strategy based on the causative agent may be more appropriate than indiscriminate combination therapy.

Background/Objectives: Meropenem is widely used to treat Pseudomonas aeruginosa infections; however, the pathogen's increasing resistance compromises its efficacy. In this study, we aimed to develop a selective culture medium for detecting the presence of meropenem-resistant Pseudomonas aeruginosa in respiratory specimens within 24 h. Methods: The medium's performance was challenged using a collection of 130 clinical Pseudomonas aeruginosa strains (of which 85 were meropenem-susceptible, 14 were meropenem-intermediate, and 21 were meropenem-resistant). Subsequently, clinical validation was carried out using 130 respiratory samples. Results: The selective medium demonstrated excellent sensitivity (average 98.7%) and specificity (average 90%) across bacterial concentrations ranging from 1 × 104 to 1 × 108 CFU/mL, and a high negative predictive value (average 99.2%) compared to the broth microdilution (BMD) method. Clinical validation with bronchoalveolar lavage (BAL) and tracheobronchial aspirate (TBA) clinical specimens (N = 130) revealed a strong performance, with 92,3% categorical agreement. Conclusions: This method accelerates susceptibility testing, is user-friendly, and delivers reliable results, contributing to the optimization of empirical treatment for respiratory tract infections.

This post-hoc analysis of a multinational, multicenter study aimed to describe and compare clinical characteristics, microbiology, and outcomes between immunosuppressed and non-immunosuppressed patients with nosocomial lower respiratory tract infections (nLRTI). The study utilized data from the European Network for ICU-related Respiratory Infections, including 1,060 adult ICU patients diagnosed with nLRTI. Descriptive statistics were used to compare baseline characteristics and pathogen distribution between groups. A Cox proportional hazards model stratified by immunosuppression status was applied to assess 28-day mortality risk, adjusting for disease severity and key clinical variables.

Immunosuppression was observed in 24.9% (264/1060) of the patients, and oncological conditions were the most common etiology of immunosuppression. Chronic pulmonary and cardiovascular diseases were the most frequent comorbidities. In both groups, Pseudomonas aeruginosa was the predominant microorganism, particularly affecting patients with immunosuppression (25.3% vs. 16.7%, p = 0.032). Cox regression model adjusted for disease severity (SAPS II), polytraumatized status, altered consciousness, and postoperative status, SAPS II remained a strong independent predictor of mortality, with each one-point increase associated with a 2.3% higher risk of death (HR: 1.023, 95% CI 1.017-1.030, p < 0.001). The analysis also revealed significant heterogeneity in mortality risk among immunosuppressed patients, with hematological malignancies, recent chemotherapy, and bone marrow transplantation associated with the highest mortality.

Immunosuppressed patients had a lower adjusted survival probability compared to non-immunosuppressed patients. Moreover, P. aeruginosa was the most frequently identified etiological pathogen in immunosuppressed patients.

Antibiotic stewardship in critically ill pneumonia patients is crucial yet challenging, partly due to the limitations of noninvasive diagnostic tests. This study reports an antibiotic de-escalation pattern informed by bronchoalveolar lavage (BAL) results, incorporating quantitative cultures and multiplex PCR rapid diagnostic tests.

We analyzed data from SCRIPT, a single-center prospective cohort study of mechanically ventilated patients who underwent a BAL for suspected pneumonia. We used the Narrow Antibiotic Therapy (NAT) score to quantify day-by-day antibiotic prescription patterns for each suspected pneumonia episode etiology (bacterial, viral, mixed bacterial/viral, microbiology-negative, and non-pneumonia control). The primary outcome was a composite of in-hospital mortality, discharge to hospice, or requiring lung transplantation during hospitalization, which we referred to as unfavorable outcomes. The secondary outcomes were duration of ICU stay, duration of intubation, and Clostridium difficile during admission. Outcomes were compared across pneumonia etiologies with the Mann-Whitney U test and Fisher's exact test.

Among 686 patients (409 men, 276 women) with 927 pneumonia episodes, NAT score analysis showed consistent antibiotic de-escalation in all pneumonia etiologies except resistant bacterial pneumonia. Microbiology-negative pneumonia was treated similarly to susceptible bacterial pneumonia. 44% viral episodes had antibiotic cessation by post-BAL day 5. Unfavorable outcomes were comparable across all pneumonia etiologies. Patients with viral and mixed bacterial/viral pneumonia had longer durations of ICU stay and intubation. Clostridium difficile was detected in 14 (2%) patients.

BAL quantitative cultures and multiplex PCR rapid diagnostic tests resulted in prompt antibiotic de-escalation in critically ill pneumonia patients. There was no evidence of increased unfavorable outcomes.

Pneumonia represents a significant global health burden with high morbidity and mortality rates, despite advances in therapeutic and preventive strategies. Airway clearance techniques (ACT), including High-Frequency Chest Wall Oscillation (HFCWO) and bilevel positive airway pressure (BiPAP), are critical in managing respiratory conditions. However, the combined effectiveness of BiPAP and HFCWO in treating adult pneumonia remains underexplored.

A retrospective cohort study was conducted at a college hospital in southern Taiwan, enrolling patients aged ≥ 18 years, admitted for pneumonia from January 2020 to December 2022, who received HFCWO therapy for ≥ 5 days in the ordinary ward. Exclusion criteria included prior mechanical ventilation before HFCWO initiation. Univariate and multivariable logistic regression models were used to assess the effectiveness of the combined use of BiPAP and HFCWO.

A total of 271 patients received HFCWO and were enrolled for analysis, including 163 patients who received both BiPAP and HFCWO. Patients receiving both BiPAP and HFCWO were associated with decreased frequency of sputum suction (OR: 2.91, 95% CI: 1.46-5.78, P = 0.002), and reduced oxygen need post-HFCWO (OR: 0.55, 95% CI: 0.33-0.91, P = 0.021). However, there was no difference in hospital stay, respiratory failure, ICU admission, or hospital death between the groups. Additionally, there was no difference in these outcomes for patients who received HFCWO twice daily compared to those who received it once daily.

Combining BiPAP and HFCWO reduces the need for sputum suction and improves oxygen demand for patients but does not change hospital days, respiratory failure, or mortality. Further large prospective cohort studies are necessary to confirm the efficacy of this management approach.

Antibiotic de-escalation (ADE) is important to help optimize antibiotic use and balance the positive and negative effects of antimicrobial therapy. ADE should be performed promptly, and infections should be treated with the shortest course of antimicrobials as clinically feasible to avoid unnecessary use of broad-spectrum antimicrobials. Several tools have been developed to increase efficient ADE, including rapid diagnostic tests (ex. multiplex PCR), MRSA nasal PCR/culture, and biomarkers. Multiplex PCR and MRSA nasal PCR/culture have been associated with reductions in inappropriate antibiotic use. Procalcitonin, a biomarker, has been associated with shorter antimicrobial durations in some studies; however, widespread use may be limited by lack of specificity for bacterial infections, cost, and lack of set cut-off points. Additional biomarkers such as IL-6, HMGB1, presepsin, sTREM-1, CD64, PSP, proadrenomedullin, and pentraxin-3 are currently being studied. As technology improves, additional tools may be leveraged to better optimize ADE even better, such as antimicrobial spectrum scoring tools and artificial intelligence (AI). Spectrum scores, which quantify antibiotic activity using specific numeric values, could be incorporated into electronic health records to identify patients on unnecessarily broad antibiotics. AI modeling has the potential to predict personal antibiograms or provide the probability that an empiric regimen may cover a particular infection, among other potential applications. This review will discuss the literature associated with ADE in the ICU, selected tools to help guide ADE, and perspectives on how to implement ADE into clinical practice.

Sepsis represents a high-risk mortality cohort among patients with severe community-acquired pneumonia (SCAP). Rapid and precise identification along with prompt decision-making, serves as a practical approach to improve patient prognosis.

This retrospective observational study enrolled adult patients with severe community-acquired pneumonia (SCAP) who were continuously hospitalized in the intensive care unit (ICU) of West China Hospital, Sichuan University, from September 2011 to September 2019. Univariate and multivariate logistic regression analyses were employed to identify independent risk factors for co-sepsis, followed by the utilization of LASSO regression to filter features to establish a nomogram. Model robustness was evaluated via the C index, receiver operating characteristic (ROC) analysis, and calculation of the area under the curve (AUC). Furthermore, its predictive accuracy was assessed via decision curve analysis (DCA).

In total, 5855 SCAP patients were included in the present study, of whom 654 developed sepsis. Patients with sepsis exhibited a prolonged length of stay in the ICU and higher mortality rates, indicating a worse prognosis than those without sepsis. We identified 15 independent risk factors associated with the development of sepsis in SCAP patients. Further analysis incorporating 9 of these features to construct a nomogram demonstrated a C index of 0.722 (95%CI 0.702-0.742), including lactate, D-dimer, respiratory rate, heart rate, albumin, hemoglobin, activated partial thromboplastin time (APTT), glucose, and C-reactive protein (CRP) levels. The AUC values and DCA curves demonstrated that the model exhibited superior accuracy and overall net benefit in predicting co-sepsis development compared with the qSOFA, CURB-65, SOFA, and APACHE II scores. Additionally, the calibration curve confirmed good concordance between the predicted probabilities of the model.

This study investigated the risk factors for co-sepsis in SCAP patients and constructed an expedited, cost-effective and personalized model for predicting the probability of co-sepsis.

Legionnaires' disease (LD) is typically treated with macrolides, including the azalide azithromycin, or quinolones. In 2013, guidelines for empirical treatment of community-acquired pneumonia at Christchurch Hospital, New Zealand were changed to prioritize oral azithromycin over IV clarithromycin.

To determine whether the change in antimicrobial guidelines led to altered outcomes for patients subsequently confirmed to have LD.

Patients with confirmed LD between 2010 and 2020 were identified from clinical and laboratory data. Hospital records were used to identify mortality, ICU admission, length of hospital stay, time to clinical stability, and time to first anti-Legionella treatment. Mean differences, risk ratios (RRs) and an interrupted time series with propensity adjustment were used to compare patient outcomes before and after the guideline change.

There were 323 patients included: 128 before and 195 after the change. Patient outcomes generally improved after the change including: mortality within 30 days (RR 0.4, 95% CI 0.2-0.8); ICU admission (RR 0.6, 95% CI 0.5-0.9); length of stay (difference -2.3 days, 95% CI -4.3 to -0.4); and time to clinical stability (difference -2.4 days, 95% CI -4.3 to -0.5). The interrupted time series analysis suggested improvements in patient outcomes may have occurred regardless of the guideline change.

Outcomes for patients with LD were not worsened by the change in antimicrobial guidelines and may have improved. Overall rates of mortality were low. This result was reassuring given the harm that may result from unnecessary use of IV compared with oral antimicrobial agents.

This prospective randomized trial examined the impact of extensive lower respiratory tract sampling and microbial analysis on treatment decisions and patient outcomes in community-acquired pneumonia (CAP). One hundred and eighteen patients were randomized to rigorous sampling (intervention group, n = 64) or standard care (control group, n = 54). The primary outcome was antibiotic therapy change based on microbiological results. Secondary outcomes included intravenous therapy duration, hospital stay length, 30-day mortality, and readmission rate. Unexpectedly, many control group patients underwent sampling at the physician's discretion, making the groups equivalent in sampling frequency. Microbiological analysis led to antibiotic therapy changes in 28% of intervention and 30% of control patients. Overall, 34% of sampled patients had treatment adjustments, generally leading to antibiotic broadening. No significant differences were observed between groups in secondary outcomes. While rigorous sampling did not significantly impact overall patient outcomes, microbiological analysis influenced treatment decisions in a substantial proportion of patients. Future studies should evaluate the effects of sampling for CAP diagnosis in settings where broader-spectrum antibiotics are the empirical treatment of choice to determine the impact on treatment decisions.

The relationships between microplastics (MP) exposure through respiratory and exacerbation of community-acquired pneumonia (CAP), as well as the potential influences of respiratory microbiota and inflammatory factors remain unknown in adults. Therefore, we conducted a cross-sectional study involving 50 non-severe CAP (NSCAP) and severe CAP (SCAP) patients to examine the associations of MP exposure in sputum (SP) and bronchoalveolar lavage fluid (BALF) samples with SCAP risk, and the underlying influences of respiratory microbiota and inflammatory factors. The average concentration of total MP was 23.24 μg/g dw and 4.49 μg/g dw in SP and BALF samples, with the detection rates of 98 % and 94 %. Participants who performing housework often or sedentary time ≤ 5h exhibited a higher proportion of high exposure to MP. Multivariable logistic regression and weighted quantile sum regression models showed the significantly positive relationships of single type or overall MP exposure with SCAP risk. Correlation analysis revealed that MP concentrations in BALF samples were significantly associated with multiple respiratory microbiota and inflammatory factors, particularly with the reduction in α-diversity indices of the respiratory microbiota. Our findings demonstrated that respiratory exposure to MP may cause the risk increase of SCAP, along with the alterations of respiratory microbiota and inflammatory factors. It is recommended that patients with CAP should reduce the respiratory exposure to MP for preventing the exacerbation of CAP in clinical practice.

Community-acquired pneumonia (CAP) is a frequent and potentially life-threatening condition. Even though the disease is common, evidence on CAP management is often of variable quality. This may be reinforced by the lack of a systematic and homogeneous way of defining the disease in randomized controlled trials (RCTs).

This study aims to assess the diagnostic criteria and definitions of the term 'community-acquired' used in RCTs on CAP management.

On the basis of the protocol (PROSPERO 2019 CRD42019147411), we conducted a systematic search of Medline/PubMed and the Cochrane Register of Controlled Trials for RCTs published or registered between 2010 and 2024.

Study eligibility criteria included completed and ongoing RCTs.

Participants included adults hospitalized with CAP.

Data were collected using a tested extraction sheet, as endorsed by the Cochrane Collaboration. After cross-checking, data were synthesized in a narrative and tabular form.

In total, 7173 records were identified through our searches. After removing records that did not fulfil the eligibility criteria, 170 studies were included. Diagnostic criteria were provided in 69.4% of studies, and the term 'community-acquired' was defined in 55.3% of studies. The most frequently included diagnostic criteria were pulmonary infiltrates (94.1%), cough (78.8%), fever (77.1%), dyspnoea (62.7%), sputum (57.6%), auscultation/percussion abnormalities (55.9%), and chest pain/discomfort (52.5%). The different criteria were used in 87 different sets across the studies. The term 'community-acquired' was defined in 57 different ways.

The diagnostic criteria and definitions of CAP in RCTs exhibit significant heterogeneity. Standardizing these criteria in clinical trials is crucial to ensure comparability across studies.

Community-Acquired Pneumonia (CAP) of Presumed Bacterial Origin: Updated Management Guidelines Community-acquired pneumonia (CAP) of presumed bacterial origin is a common condition with varying severity, requiring either outpatient, hospital, or even critical care management. The French Infectious Diseases Society (SPILF) and the French Language Pulmonology Society (SPLF), in collaboration with the French Societies of Microbiology (SFM), Emergency Medicine (SFMU), Radiology (SFR), and Intensive Care Medicine (SRLF), along with representatives of general practice, have coordinated an update of the previous management guidelines, which dated back to 2010. From a therapeutic perspective, the updated recommendations define the choice of initial empiric antibiotic therapy, indications for combination therapy, the use of anti-Pseudomonas beta-lactams, antibiotic treatment duration, and the indications and modalities for prescribing systemic corticosteroids. On a biological level, indications for biomarkers and microbiological investigations have been refined. Regarding imaging, the role of different modalities in the diagnosis and follow-up of CAP has been reassessed, including chest X-ray, pleuropulmonary ultrasound, and thoracic CT scan.