Search Results (542)

Background: Pediatric pleural empyema is a major complication of community-acquired pneumonia and remains associated with substantial morbidity despite advances in vaccination, antimicrobial therapy, and supportive care. Intrapleural fibrinolytic therapy has become an important minimally invasive treatment for complicated parapneumonic effusions and empyema, but uncertainty persists regarding the optimal fibrinolytic agent, treatment protocols, patient selection, and indications for surgical intervention. Methods: A narrative review of the literature was conducted to summarize current evidence on the use of intrapleural fibrinolytic therapy in pediatric pleural empyema. Experimental studies, randomized controlled trials, observational studies, systematic reviews, meta-analyses, and international clinical practice guidelines were critically reviewed. Particular attention was paid to the biological rationale for fibrinolysis, pharmacological characteristics of available agents, comparative effectiveness with video-assisted thoracoscopic surgery (VATS), practical treatment protocols, safety, and future research priorities. Results: Intrapleural fibrinolysis effectively improves pleural drainage by lysing fibrin septations during the fibrinopurulent stage of empyema and is associated with shorter hospitalization compared with chest-tube drainage alone. Urokinase remains the fibrinolytic agent supported by the highest-quality pediatric randomized evidence, whereas alteplase has demonstrated favorable outcomes in observational studies and randomized comparisons with VATS. Current evidence indicates comparable clinical outcomes between fibrinolysis and primary VATS in appropriately selected children, although fibrinolysis is generally associated with lower treatment costs and avoidance of surgery in most patients. Conventional-dose fibrinolytic therapy has an acceptable safety profile, with clinically significant bleeding reported only rarely. Current pediatric evidence does not support the routine addition of DNase to tissue plasminogen activator. Conclusions: Intrapleural fibrinolytic therapy represents a safe, effective, and minimally invasive first-line treatment for most children with complicated parapneumonic effusions and pleural empyema requiring drainage. Management should be individualized within a multidisciplinary framework, integrating timely diagnosis, image-guided pleural drainage, appropriate antimicrobial therapy, and selective surgical intervention. Future multicenter studies are needed to optimize fibrinolytic protocols, validate predictive biomarkers, and further standardize clinical management. Full article

Background: Acinetobacter baumannii and Klebsiella pneumoniae are important causes of hospital-acquired infections in pediatric patients, but comparative data on their clinical manifestations and inflammatory biomarkers remain limited. Methods: We retrospectively analyzed 55 children with single-positive blood cultures for A. baumannii (n = 20) or K. pneumoniae (n = 35), together with 30 healthy controls. Results: CRP, IL-6, and IL-10 were higher in infected children than in healthy controls. Logistic regression identified CRP and the IL-6/IL-10 ratio as exploratory correlates of infection. In ROC analyses distinguishing infected children from healthy controls, IL-6 showed the highest AUC, followed by IL-10 and CRP. In pathogen-level analyses, the IL-6/IL-10 ratio and lipase showed exploratory discriminatory signals. Conclusions: In this small retrospective case–control cohort, CRP, IL-6, and IL-10 were associated with microbiologically confirmed infection. Lipase may represent a potential biomarker for differentiating A. baumannii from K. pneumoniae infection, but its clinical utility requires prospective validation in larger multicenter cohorts using clinically relevant inpatient control groups. Full article

Background/Objective: To externally validate our previously published machine learning model for identifying hospitalized patients with community-acquired pneumonia (CAP) at low risk of respiratory deterioration or death using the Medical Information Mart for Intensive Care IV (MIMIC-IV) database. Methods: This is a retrospective cohort study of adult patients (≥18 years) who were admitted with CAP and acute hypoxemic respiratory failure using the publicly available MIMIC-IV critical care dataset (Beth Israel Deaconess Medical Center, Boston, MA). We conducted an external validation study of a previously developed gradient boosting machine (GBM) model without recalibration using data available within the first 6 h of hospital admission. Results: For the primary composite outcome (need for advanced respiratory support [high flow nasal cannula (HFNC), non-invasive mechanical ventilation (NIMV), invasive mechanical ventilation (IMV)] or in-hospital death), the gradient boosting model demonstrated comparable performance in the derivation and external validation cohorts. The area under the receiver operating characteristic curve (AUC) was 0.713 in the Mayo cohort (n = 4379) and 0.689 in the MIMIC-IV cohort. Accuracy was 0.612 (95% confidence interval [CI], 0.595–0.628) versus 0.606 (95% CI 0.600–0.611), specificity 0.574 versus 0.523, sensitivity 0.723 versus 0.754, NPV 0.860 versus 0.842, and PPV 0.364 versus 0.401, respectively. For secondary outcomes, model discrimination was comparable between cohorts. The AUC for in-hospital mortality was 0.727 in the Mayo Cohort versus 0.733 in MIMIC-IV; for IMV, 0.736 versus 0.724; and for NIMV, 0.732 versus 0.708. Conclusions: Our machine learning algorithm demonstrated good discrimination and a high negative predictive value for identifying low-risk hospitalized CAP patients for respiratory deterioration or death in the external MIMIC-IV dataset, supporting its potential utility for prognostic enrichment in pneumonia clinical trials. Full article

Enterobacteriaceae are a diverse family of Gram-negative, rod-shaped, facultatively anaerobic bacteria that serve as important indicators of food safety. Many species within this family, including common foodborne pathogens, are major contributors to both community- and hospital-acquired infections. The widespread use of antibiotics in agriculture has facilitated the emergence and dissemination of antimicrobial-resistant bacteria in food products, livestock, and the environment. This study investigated the prevalence and genomic characteristics of extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae isolated from food sources in Saudi Arabia. A total of 160 isolates preserved in the Saudi Food and Drug Authority (SFDA) biobank were screened for antimicrobial resistance using indicator β-lactam antibiotics according to CLSI guidelines. Phenotypic screening indicated that Escherichia coli O145, E. coli O157, Klebsiella pneumoniae, and Cronobacter sakazakii isolates were not ESBL producers. In contrast, ESBL production was detected among Salmonella spp. isolates, and 13 confirmed ESBL-producing Salmonella isolates were subsequently subjected to whole-genome sequencing (WGS). Genomic analysis identified the ESBL gene blaCTX-M-65, along with multiple antimicrobial resistance determinants, virulence-associated genes, and plasmid replicons, predominantly belonging to the IncFIB and IncX families. These findings provide important insights into the occurrence of ESBL-producing Enterobacteriaceae in food sources and highlight the value of integrating phenotypic and genomic approaches for antimicrobial resistance surveillance within food safety systems. Full article

Background/Objectives: 23-valent pneumococcal polysaccharide vaccine (PPV23) effectiveness against community-acquired pneumonia (CAP) remains controversial, with critical gaps in low-coverage settings and beyond 5 years post-vaccination. We estimated real-world PPV23 effectiveness against CAP hospitalization and characterized its duration among elderly adults in a low-coverage region. Methods: A multicenter matched case–control study was conducted across 14 hospitals in Eastern China (2018–2022). Cases were patients aged ≥60 years hospitalized with clinically diagnosed CAP. Up to three controls per case were matched on sex, age (±3 years), admission date (±5 days), hospital, and residential community. Conditional logistic regression estimated vaccine effectiveness (VE), adjusting for chronic comorbidities and healthcare utilization. Results: Among 6645 cases and 15,806 controls, 5-year PPV23 coverage was 2.14% (cases) and 2.76% (controls). PPV23 was associated with a 22.5% reduction in CAP hospitalization (adjusted VE = 22.5%, 95% CI: 4.1% to 37.3%). Protection was concentrated in non-severe CAP (adjusted VE = 25.7%, 95% CI: 7.0% to 40.7%), with no significant effect in severe CAP (adjusted VE = −11.7%, 95% CI: −115.1% to 42.0%). Extending the exposure window to 6 years yielded no significant VE (adjusted VE = 17.3%, 95% CI: −1.8% to 32.8%). Conclusions: PPV23 provides meaningful protection against CAP hospitalization in elderly adults in low-coverage settings, only for non-severe disease. Waning efficacy beyond 5 years supports revaccination at that interval. Full article

Community-acquired pneumonia is one of the main causes of morbidity and mortality due to infections worldwide. This has led to the study of the use of corticosteroids as adjunctive therapy, which has shown an inclination to provide clinical benefits. However, controversy persists regarding the use of one corticosteroid over another Objectives: Evaluate the outcomes associated with the use of hydrocortisone versus methylprednisolone in patients with community-acquired pneumonia. Methods: We conducted a multicenter retrospective cohort study that included hospitalized adults diagnosed with CAP at two high-complexity clinics in Colombia between 2010 and 2020. Propensity score matching was used in a 1:1 ratio to balance the baseline characteristics between the hydrocortisone and methylprednisolone groups. The primary outcome was 30-day mortality. Secondary outcomes included septic shock, vasopressor use, admission to the intensive care unit, mechanical ventilation, and other hospital outcomes. Survival analyses were performed using Kaplan–Meier curves and estimates of the average treatment effect, as well as subgroup analyses according to the dose and duration of treatment. Results: The study initially included 366 patients, with significant baseline differences between groups. After matching, an adjusted cohort of 168 patients (84 per group) was obtained, with an adequate balance of clinical, paraclinical, and severity-related variables. No statistically significant differences were found in 30-day mortality between patients who received hydrocortisone and those who received methylprednisolone before or after matching. Additionally, no differences were detected in the secondary clinical outcomes. Survival analyses revealed no differences according to corticosteroid type, treatment duration, or administered dose. Conclusions: In this retrospective propensity-score-matched cohort study, no differences were observed in 30-day mortality or other clinical outcomes between hydrocortisone and methylprednisolone in patients with community-acquired pneumonia. Full article

Background/Objectives: Community-acquired pneumonia (CAP) is a leading cause of ICU admission and death in older adults, yet the severity scores used in this setting were not developed for, or validated in, older intensive care patients. We compared a pneumonia-specific score (SMART-COP) with the general ICU scores SOFA and APACHE II and with CURB-65 for predicting adverse outcomes in this population. Methods: In this single-center prospective observational study, 227 consecutive patients aged ≥65 years admitted to the ICU with CAP were enrolled. SMART-COP and CURB-65 were calculated at hospital admission and SOFA and APACHE II at ICU admission. The discrimination of each score for four outcomes—in-ICU mortality, need for intubation, vasopressor requirement, and hospital-acquired pneumonia (HAP)—was assessed by ROC analysis, and areas under the curve (AUCs) were compared pairwise using the DeLong test. Results: All four scores predicted mortality, intubation, and vasopressor requirement (all p ≤ 0.001), but none discriminated well for HAP (all AUCs < 0.70). SMART-COP had the highest AUCs for mortality (0.846) and intubation (0.870), significantly exceeding CURB-65 (both p < 0.01) while performing comparably to SOFA and APACHE II. SOFA was the strongest predictor of vasopressor requirement (AUC: 0.867). Conclusions: In older ICU patients with CAP, SMART-COP—calculable from routine parameters at admission—matched far more complex ICU scores for mortality and intubation and outperformed CURB-65. The optimal score depends on the outcome of interest. Full article

Background/Objectives: Intensive care unit (ICU) mortality reflects interactions between baseline vulnerability, acute physiological derangement, ICU-acquired infection, and the intensity of organ-support therapy. Methods: This single-center retrospective cohort study included 3323 adult first ICU hospitalizations at the University Clinical Hospital in Bialystok, Poland, between 1 January 2017 and 1 June 2023. Secondary ICU admissions/readmissions, patients aged <18 years, and one pregnancy admission were excluded. Patients were classified as ICU survivors (n = 1778) or ICU non-survivors (n = 1545). Variables were compared using t-tests, chi-square tests, or Fisher exact tests, and an adjusted logistic regression model was fitted as an exploratory prognostic model. Results: ICU mortality was 46.5%, and 28-day ICU mortality was 40.2%. Non-survivors were older than survivors (66.7 ± 15.1 vs. 60.9 ± 17.2 years; p < 0.001) and more frequently had arterial hypertension, diabetes mellitus, COVID-19, ischemic heart disease, atrial fibrillation, renal failure, and acute myocardial infarction or ischemic stroke. In the adjusted model, ICU mortality was associated with age per 10 years (OR 1.32, 95% CI 1.18–1.47), COVID-19 (OR 3.15, 95% CI 2.07–4.79), ventilator-associated pneumonia (OR 1.68, 95% CI 1.22–2.30), lactate per 1 mmol/L (OR 1.29, 95% CI 1.16–1.43), pH per 0.1-unit decrease (OR 1.79, 95% CI 1.41–2.29), mechanical ventilation (OR 14.74, 95% CI 3.40–63.87), cardiopulmonary resuscitation (OR 9.45, 95% CI 4.67–19.13), renal replacement therapy (OR 2.01, 95% CI 1.39–2.91), and treatment of acidosis or alkalosis (OR 1.95, 95% CI 1.29–2.94). Conclusions: ICU non-survival was associated with older age, COVID-19, cardiovascular and renal vulnerability, ICU-acquired infection, inflammatory and metabolic dysfunction, and early requirement for rescue organ-support interventions. These findings should be interpreted as adjusted associations, not causal effects. Full article

No previous sub-Saharan studies have compared patients with community-acquired pneumonia (CAP) and COVID-19 pneumonia, the focus of this study. Consecutive adult patients hospitalized with CAP (n = 59) or COVID-19 pneumonia (n = 74) were compared regarding multiple characteristics, including cardiac biomarkers. In multivariable logistic regression analysis, differences were noted among various clinical features. Troponin I concentrations (p = 0.00028) and the Troponin I/NT-pro BNP ratio (p = 0.00048) were significantly higher in COVID-19 compared with CAP. After adjustment for age, these differences remained significant (troponin I p = 0.0019; ratio p = 0.00054), while BNP concentrations were now higher in CAP (p = 0.009). PCA demonstrated that BNP and NT-pro BNP contributed most strongly to the dominant cardiac biomarker signature, suggesting shared cardiopulmonary stress across both diseases. Exploratory subgroup analyses suggested higher troponin I levels among people living with HIV and COVID-19, although interaction modelling did not demonstrate significant effect modification by HIV status. Both CAP and COVID-19 pneumonia were associated with evidence of cardiac stress; however, COVID-19 demonstrated a relatively stronger myocardial injury signature characterized by higher troponin I concentrations and an increased Troponin I/NT-pro BNP ratio while CAP had evidence of greater hemodynamic cardiac strain, as evidenced by the higher levels of BNP. The findings suggest that the mechanisms of cardiac involvement may differ between viral and bacterial respiratory infections. Full article

Serratia marcescens has emerged as an important opportunistic pathogen in intensive care units (ICUs), where critically ill patients, invasive devices, antimicrobial exposure, and complex environmental reservoirs create favorable conditions for colonization, infection, and recurrent outbreaks. This narrative review synthesizes evidence from the past decade regarding the clinical and molecular epidemiology, environmental persistence, device-associated transmission, biofilm-mediated resistance, and infection-control strategies of S. marcescens in ICU settings. The literature was reviewed using an integrative approach informed by Ferrari’s narrative review framework, with thematic synthesis across clinical, microbiological, environmental, and genomic domains. Recent evidence indicates that ICU-associated S. marcescens infections frequently involve respiratory tract colonization, ventilator-associated pneumonia, bloodstream infection, urinary tract infection, and device-related transmission. Hospital water systems, sink drains, wet surfaces, ventilator circuits, reusable equipment, and contaminated antiseptic or liquid products may serve as persistent reservoirs, particularly when biofilm formation supports long-term survival and recurrent dissemination. At the molecular level, S. marcescens demonstrates substantial genomic diversity, intrinsic and acquired antimicrobial resistance, inducible AmpC β-lactamase activity, efflux-mediated tolerance, and plasmid-associated resistance gene transfer. This review particularly emphasizes the molecular determinants that enable S. marcescens to persist in ICU ecosystems, including AmpC-mediated β-lactam resistance, efflux-associated tolerance, quorum-sensing-regulated biofilm formation, plasmid-mediated horizontal gene transfer, and WGS-defined clonal transmission. Whole-genome sequencing, rapid molecular diagnostics, active surveillance, environmental sampling, and integrated infection-control bundles have become increasingly important for distinguishing clonal outbreaks from endemic transmission and guiding timely interventions. Emerging perspectives emphasize the need to combine antimicrobial stewardship, environmental engineering, respiratory-care auditing, anti-biofilm strategies, and AI-assisted real-time surveillance into adaptive ICU infection-control frameworks. Overall, S. marcescens should be regarded not merely as an episodic outbreak organism, but as a highly adaptable ICU-associated pathogen requiring multidisciplinary prevention strategies. Full article

Background: Non-pharmaceutical interventions during the COVID-19 pandemic altered respiratory pathogen circulation, and a bacterial rebound followed once restrictions were lifted. We describe pediatric pneumococcal respiratory infections and their bacterial co-detections in the immediate post-pandemic period. Methods: We retrospectively analyzed respiratory specimens from children aged 0–18 years tested with a multiplex real-time PCR panel (Allplex Respiratory Panel, Seegene, Seoul, South Korea; seven bacterial pathogens) restricted to this predefined bacterial spectrum at a tertiary pediatric hospital in Galați, Romania, during 2022 and 2023. A total of 2546 panels were performed in 2022 and 3250 in 2023, allowing pneumococcal positivity rates to be calculated. Proportions are reported with Wilson 95% confidence intervals; associations were tested with Pearson chi-square and Fisher exact tests in SPSS v.23. Results: Children with detected Streptococcus pneumoniae rose from 100 to 415, corresponding to a rise in pneumococcal positivity from 3.9% (100/2546) to 12.8% (415/3250). Among the positive children, pneumococcus–Haemophilus influenzae co-detection increased from 33.0% to 45.1% (odds ratio 1.63, 95% CI 1.02–2.61; p = 0.029), while pneumococcus alone fell from 60.0% to 50.1%. Boys, urban residence, and early childhood predominated, and community-acquired pneumonia diagnoses rose from 61 to 214. No profile–demographic association reached significance (panel–residence 2023, p = 0.063). Conclusions: A post-pandemic rise in pediatric pneumococcal detections and increasing H. influenzae co-detection were observed, supporting syndromic multiplex PCR in rapid pediatric diagnostics and antimicrobial stewardship. Full article

Background/Objectives: Acute pulmonary embolism (PE) and hospitalization-requiring community-acquired pneumonia (CAP) may present with overlapping clinical, laboratory, and radiological features. Soluble CD40 ligand (sCD40L) is a platelet-derived thrombo-inflammatory mediator that may be influenced by both thrombotic and inflammatory processes. This study retrospectively compared on-admission serum sCD40L concentrations between selected hospitalized patients with established acute PE and selected patients with hospitalization-requiring CAP. Methods: This single-center retrospective exploratory comparative biomarker study included 82 hospitalized adults: 48 with computed tomography pulmonary angiography (CTPA)-confirmed acute PE and 34 with hospitalization-requiring CAP defined using CURB-65-supported admission criteria. Stored admission serum samples were used for sCD40L measurement. Between-group comparison was the primary analysis; receiver operating characteristic (ROC) analysis was performed as a secondary exploratory description of the apparent within-sample discriminatory signal. Results: sCD40L was higher in acute PE than in hospitalization-requiring CAP (median 821.3 vs. 629.0 pg/mL; p < 0.001). ROC analysis demonstrated a strong exploratory within-sample discriminatory signal (AUC 0.951, 95% CI 0.905–0.997). After excluding five patients with recorded antiplatelet or rivaroxaban exposure, the apparent signal remained similar (AUC 0.945; bootstrap 95% CI 0.891–0.984), and sCD40L remained associated with PE in a Firth-penalized model adjusted for platelet count and COPD (OR 3.39 per 50 pg/mL, 95% CI 2.00–7.71; p < 0.001). Conclusions: In this retrospective selected two-group comparison, on-admission serum sCD40L concentrations were higher in established acute PE than in hospitalization-requiring CAP. ROC-derived estimates should be interpreted only as apparent within-sample discrimination and not as a replacement for D-dimer, clinical probability assessment, or imaging-based PE diagnosis. Prospective validation in unselected suspected-PE cohorts is required before any diagnostic or clinical use can be considered. Full article

Pediatric respiratory infections remain among the leading causes of emergency department visits, hospitalization and pediatric intensive care unit (PICU) admission. Although most acute respiratory infections in children are viral, clinical manifestations overlap substantially among viral, bacterial and atypical pathogens, creating diagnostic uncertainty and promoting empirical antimicrobial use. Rapid antigen tests, nucleic acid amplification tests, multiplex respiratory panels and metagenomic sequencing have expanded the ability to detect pathogens within clinically actionable timeframes. However, evidence from pediatric emergency trials indicates that rapid pathogen detection alone does not necessarily reduce antibiotic prescribing or healthcare costs. These findings suggest that the value of rapid diagnostics depends less on analytical breadth than on whether testing is applied to the right child, in the right clinical scenario and within a predefined decision pathway. This narrative review reorganizes the evidence around a scenario-driven top-pathogen framework. Top pathogens are defined as organisms that, in a specific age group, syndrome, season or care setting, have high prevalence, severe disease potential, transmissibility, treatment implications, antimicrobial resistance relevance or infection-control value. We discuss how top-pathogen testing should differ across emergency triage, inpatient ward management, severe pneumonia, PICU care, hospital-acquired pneumonia, ventilator-associated pneumonia and outbreak settings. We further examine the economic mechanisms through which rapid testing may generate value, including reduced unnecessary antibiotics, timely antiviral therapy, optimized isolation, shorter length of stay, reduced repeated testing and prevention of healthcare-associated transmission. Finally, we propose implementation principles centered on diagnostic stewardship, antimicrobial stewardship, local epidemiology and real-world cost-effectiveness evaluation. A scenario-driven top-pathogen strategy may provide a practical bridge between broad syndromic testing and precision infectious disease management in children. Full article

Background: Hospital-acquired infections (HAIs) represent the most significant complications in patients hospitalized for severe burn injuries, after the immediate post-burn resuscitation phase, and are associated with substantial morbidity and mortality. Methods: This is a narrative review. Evidence was extracted mainly with an in-depth search of MEDLINE, focusing on guidelines, randomized controlled trials, and relevant observational studies published in the last 25 years. The reference lists of the most relevant publications were screened to retrieve additional relevant information. Results: Wound infections, bloodstream infections, pneumonia, and urinary tract infections account for the majority of infectious complications. Their diagnosis can be challenging, particularly in the context of wound infections and sepsis. Burn severity and the resulting disruption of tissue and organ homeostasis can alter the pharmacokinetic and pharmacodynamic (PK/PD) properties of antibiotics, rendering standard dosing and administration strategies inadequate. Higher doses, prolonged or continuous infusions, and therapeutic drug monitoring may be required to optimize antibiotic exposure. The emergence of multidrug-resistant (MDR) pathogens (particularly MDR Gram-negative bacilli) has been widely reported across diverse epidemiological settings and occurs frequently in patients with prolonged hospitalization, further complicating treatment. As a result, the use of broad-spectrum antibiotics is substantial, both for empirical therapy and for targeted treatment. Although antimicrobial stewardship programs can promote more appropriate antibiotic use, evidence on how to effectively implement these strategies in Burn Intensive Care Units remains limited. Conclusions: HAIs in burn patients represent a highly complex clinical scenario. Clinical severity is often significant, diagnosis can be challenging, and MDR pathogens are very prevalent, with high consumption of broad-spectrum antibiotics. Moreover, PK/PD properties of antibiotics can be altered. Antimicrobial stewardship can promote appropriate antimicrobial use, but implementation in this setting has not been adequately studied. Close multidisciplinary collaboration between burn specialists and infectious diseases physicians is essential to ensure effective patient management. Full article

Background: Pneumonia is a common cause of hospitalization and a significant contributor to worldwide morbidity and mortality. Effective definitive antimicrobial therapy for pneumonia relies on accurate identification of bacterial pathogens and their resistance patterns. Therefore, this study aims to evaluate the distribution bacterial pathogens and their antimicrobial resistance patterns, as well as clinical factors associated with outcomes among hospitalized pneumonia patients. Methods: This retrospective cohort study was conducted at Dr. Hasan Sadikin General Hospital, Indonesia, and included adult patients hospitalized with pneumonia between January and December 2024. Clinical, demographic, microbiological, and outcome data were extracted from electronic medical records and the laboratory system. Bacterial distribution, antimicrobial patterns, and clinical outcomes were analyzed descriptively and compared across pneumonia types. Multivariable regression analyses were performed to identify factors associated with in-hospital mortality and length of hospital stay. Results: A total of 662 hospitalized pneumonia patients were included with Gram-negative bacteria (i.e., Klebsiella pneumonia, Acinetobacter baumannii, and Pseudomonas aeruginosa) identified as the most common pathogens. Carbapenem-resistant Acinetobacter baumannii (CR-Ab) and Klebsiella pneumoniae (CR-Kp) were the most frequently identified resistant pathogens, particularly in hospital-acquired (HAP) and ventilator-associated pneumonia (VAP). HAP and VAP were independently associated with higher in-hospital mortality and longer hospital stay compared to community-acquired pneumonia (CAP). In addition, CR-Ab and difficult-to-treat Pseudomonas aeruginosa (DTR-Psa) were associated with prolonged hospitalization. Conclusions: Type of pneumonia, bacterial pathogens and resistance patterns were associated with in-hospital mortality and length of hospital stay. These findings highlight the importance of ongoing microbiological surveillance, antimicrobial stewardship, and infection prevention strategies to optimize pneumonia management and clinical outcomes. Full article