Relapsing bronchopneumonia due to community-associated methicillin-resistant Staphylococcus aureus: a case report.

BACKGROUND: The emergence of community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) has increased the incidence of community-onset MRSA infection. Respiratory tract infections caused by MRSA has been noted for their severity; however, repeated relapses that require extended antibiotic therapy are rare. CASE PRESENTATION: We report a case of relapsing bronchopneumonia caused by CA-MRSA in a 56-year-old man. The patient responded to antibiotics, but repeatedly relapsed after stopping treatment. MRSA was consistently isolated from airway specimens during each relapse. Extended oral antibiotic treatment with trimethoprim/sulfamethoxazole (TMP/SMX) for 6 months achieved infection control. Whole-genome sequencing of the isolated strain revealed that the causative agent was sequence type (ST)1/staphylococcal cassette chromosome mec (SCCmec) type IVa, a clone that is rapidly increasing in Japan. DISCUSSION AND CONCLUSIONS: This patient had an unusual course of MRSA bronchopneumonia with repeated relapses. Although the choice of antibiotics for long-term use in MRSA respiratory tract infections has not been well established, TMP/SMX was effective and well tolerated for long-term therapy in this case. The clinical course of infections related to the rapid emerging clone, ST1/SCCmec type IVa warrants further attention.

Alveolar-arterial oxygen gradient: An early marker to predict the severity of community-acquired pneumonia in children.

To study the clinical significance of alveolar-arterial oxygen gradient (PA-aO2) for children with community-acquired pneumonia (CAP). A prospective study was carried out from January 2020 to June 2023, Overall, 100 patients were included in the study, 35 had severe pneumonia, whereas, 65 had non-severe pneumonia. Clinical and laboratory data were retrospectively collected at the time of hospital admission and during hospitalization. Patients were divided into severe and non-severe groups. PA-aO2 was significantly higher among children with severe pneumonia, as determined by WHO, PRESS (P < .001). PA-aO2 was significantly higher among children with mechanical ventilation, shock, sepsis, and mortality. Receiver operating characteristic curve (ROC) analysis for PA-aO2 showed that the area under the curve was 0.76 (P value < .05), with a sensitivity of 84.3% and a specificity of 67.9%. Our study suggests that PA-aO2 level has a predictive value for detecting community-acquired pneumonia severity in children.

Construction and external validation of a scoring prediction model for mortality risk within 30 days of community-acquired pneumonia in children admitted to the pediatric intensive care unit: A multicenter retrospective case-control study.

In this study, we constructed and validated a scoring prediction model to identify children admitted to the pediatric intensive care unit (PICU) with community-acquired pneumonia (CAP) at risk for early death. Children with CAP who were admitted to the PICU were included in the training set and divided into death and survival groups according to whether they died within 30 days of admission. For univariate and multifactorial analyses, demographic characteristics, vital signs at admission, and laboratory test results were collected separately from the 2 groups, and independent risk factors were derived to construct a scoring prediction model. The ability of the scoring model to predict CAP-related death was validated by including children with CAP hospitalized at 3 other centers during the same period in the external validation set. Overall, the training and validation sets included 296 and 170 children, respectively. Univariate and multifactorial analyses revealed that procalcitonin (PCT), lactate dehydrogenase (LDH), activated partial thromboplastin time (APTT), and fibrinogen (Fib) were independent risk factors. The constructed scoring prediction model scored 2 points each for PCT ≥ 0.375 ng/mL, LDH ≥ 490 U/L, and APTT ≥ 31.8 s and 1 point for Fib ≤ 1.78 g/L, with a total model score of 0-7 points. When the score was ≥ 5 points, the sensitivity and specificity of mortality diagnosis in children with CAP were 72.7% and 87.5%, respectively. In the external validation set, the sensitivity, specificity, and accuracy of the scoring model for predicting the risk of CAP-related death were 64.0%, 92.4%, and 88.2%, respectively. Constructing a scoring prediction model is worth promoting and can aid pediatricians in simply and rapidly evaluating the risk of death in children with CAP, particularly those with complex conditions.

Diagnostic and Prognostic Value of Peripheral Neutrophil CD64 Index in Elderly Patients with Community-Acquired Pneumonia.

Community-acquired pneumonia (CAP) is a leading cause of hospitalization and mortality in the elderly. The peripheral blood neutrophil CD64 (nCD64) index is increasingly recognized for its association with poor pneumonia prognosis. A comprehensive investigation involving 128 elderly patients diagnosed with CAP, including 96 with non-severe CAP and 32 with severe CAP, from January 2020 to January 2021 was performed. The nCD64 index, CD4+, CD8+, C-reactive protein (CRP), white blood cell (WBC) count, procalcitonin (PCT), neutrophil (NEUT), and B lymphocyte count were determined using flow cytometry. Our findings reveal that patients with severe CAP exhibited significantly higher levels of nCD64 index, NEUT, WBC, CRP, and PCT. Intriguingly, lower CRP, nCD64 index, CURB-65 score, and PCT were associated with a higher survival rate. Notably, the nCD64 index demonstrated remarkable predictive efficiency for 28-d survival in CAP patients [area under the curve (AUC) = 0.907], surpassing other markers and even showing enhanced predictive power when combined with the CURB-65 score (AUC = 0.905). Furthermore, a negative association was observed between the nCD64 index and both CD4+, CD4+/CD8+ ratios, and B lymphocytes, highlighting its potential role in immune dysregulation. These findings underscore the critical importance of the nCD64 index in the early diagnosis, risk stratification, and prognostic evaluation of infections and immune responses in elderly CAP patients.

Diagnostic Stewardship in Community-Acquired Pneumonia With Syndromic Molecular Testing: A Randomized Clinical Trial.

Importance: Lower respiratory tract (LRT) infections, including community-acquired pneumonia (CAP), are a leading cause of hospital admissions and mortality. Molecular tests have the potential to optimize treatment decisions and management of CAP, but limited evidence exists to support their routine use. Objective: To determine whether the judicious use of a syndromic polymerase chain reaction (PCR)-based panel for rapid testing of CAP in the emergency department (ED) leads to faster, more accurate microbiological test result-based treatment. Design, Setting, and Participants: This parallel-arm, single-blinded, single-center, randomized clinical superiority trial was conducted between September 25, 2020, and June 21, 2022, in the ED of Haukeland University Hospital, a large tertiary care hospital in Bergen, Norway. Adult patients who presented to the ED with suspected CAP were recruited. Participants were randomized 1:1 to either the intervention arm or standard-of-care arm. The primary outcomes were analyzed according to the intention-to-treat principle. Intervention: Patients randomized to the intervention arm received rapid syndromic PCR testing (BioFire FilmArray Pneumonia plus Panel; bioMérieux) of LRT samples and standard of care. Patients randomized to the standard-of-care arm received standard microbiological diagnostics alone. Main Outcomes and Measures: The 2 primary outcomes were the provision of pathogen-directed treatment based on a microbiological test result and the time to provision of pathogen-directed treatment (within 48 hours after randomization). Results: There were 374 patients (221 males [59.1%]; median (IQR) age, 72 [60-79] years) included in the trial, with 187 in each treatment arm. Analysis of primary outcomes showed that 66 patients (35.3%) in the intervention arm and 25 (13.4%) in the standard-of-care arm received pathogen-directed treatment, corresponding to a reduction in absolute risk of 21.9 (95% CI, 13.5-30.3) percentage points and an odds ratio for the intervention arm of 3.53 (95% CI, 2.13-6.02; P < .001). The median (IQR) time to provision of pathogen-directed treatment within 48 hours was 34.5 (31.6-37.3) hours in the intervention arm and 43.8 (42.0-45.6) hours in the standard-of-care arm (mean difference, -9.4 hours; 95% CI, -12.7 to -6.0 hours; P < .001). The corresponding hazard ratio for intervention compared with standard of care was 3.08 (95% CI, 1.95-4.89). Findings remained significant after adjustment for season. Conclusions and Relevance: Results of this randomized clinical trial indicated that routine deployment of PCR testing for LRT pathogens led to faster and more targeted microbial treatment for patients with suspected CAP. Rapid molecular testing could complement or replace selected standard, time-consuming, laboratory-based diagnostics. Trial Registration: ClinicalTrials.gov Identifier: NCT04660084.

Hypoalbuminemia as predictor of thrombotic events in patients with community-acquired pneumonia.

BACKGROUND: Hypoalbuminemia complicates acute diseases and infections and is associated with a worst prognosis. The aim is to evaluate whether hypoalbuminemia is associated with higher incidence and risk of thrombotic events in community-acquired pneumonia. METHODS: We retrospectively collected data from a prospective study investigating the incidence of thrombotic events in community-acquired pneumonia hospitalized patients from 2011 to 2016 at University-Hospital Policlinico Umberto I. Baseline characteristics and outcomes were collected. Incidence of outcomes were calculated. Kaplan-Meier curves were created, Cox model used to identify predictors for the outcomes, and competing risk analysis performed. RESULTS: From a total of 231 patients, 130 (56.3%) and 101 (43.7%) had or not hypoalbuminemia. Age, proportion of female, BMI, major comorbidities, and severity of pneumonia were similar between two subgroups. A less proportion of patients with hypoalbuminemia received antithrombotic and statin therapy. Median hospital stay was 11 days in both subgroups. Patients with hypoalbuminemia had higher D-dimer and high- sensitivity C-reactive-protein values with an inverse relation between albumin values and these markers. Incidence of thrombotic events was 26 and 11 per 1000 patient-days in patient with and without hypoalbuminemia. At Cox model, hypoalbuminemia was associated with thrombotic events development in univariable (hazard ratio; 2.67, 95% confidence intervals, 1.30-5.40) and multivariable (hazard ratio 3.19; 95% confidence intervals, 1.48-6.89) analysis. CONCLUSIONS: More than a half of patients with community acquired pneumonia had hypoalbuminemia that is associated with a doubled incidence and a three-fold increased risk of thrombotic events. The inverse relation between baseline albumin and D-dimer values confirms this association.

Risk of Multidrug-Resistant Pathogens in Severe Community-Acquired Pneumonia.

Severe community-acquired pneumonia (SCAP) is difficult to treat when caused by difficult-to-treat (DTR) pathogens because of limited treatment options and poorer clinical outcomes. Over time, several predictive scoring systems based on risk factors for infection with multidrug resistant pathogens have been developed. We reviewed the available tools for identifying DTR pathogens as the cause of SCAP, both predictive scoring systems and rapid diagnostic methods, to develop management strategies aimed at early identification of DTR pathogens, reducing broad-spectrum antibiotic use and improving clinical outcomes. The scoring systems reviewed show considerable heterogeneity among them at the level of the region studied, the definition of risk factors, as well as which DTR pathogens are the target pathogens. The models described have shown limited effectiveness in reducing inappropriate antibiotic treatment or improving patient outcomes by themselves. However, predictive models could serve as a first step in identifying DTR pathogen infections as part of a larger detection algorithm. Rapid diagnostic tools, such as multiplex polymerase chain reaction, would be useful for the rapid identification of pneumonia-causing pathogens and their resistance mechanisms. In resource-limited settings, rapid tests should be limited to patients at high risk of developing SCAP due to DTR pathogens. We propose an integrative algorithm based on the different scores, taking into account local epidemiological data, where ideally each center should have an antimicrobial stewardship program.

Artificial intelligence for the optimal management of community-acquired pneumonia.

PURPOSE OF REVIEW: This timely review explores the integration of artificial intelligence (AI) into community-acquired pneumonia (CAP) management, emphasizing its relevance in predicting the risk of hospitalization. With CAP remaining a global public health concern, the review highlights the need for efficient and reliable AI tools to optimize resource allocation and improve patient outcomes. RECENT FINDINGS: Challenges in CAP management delve into the application of AI in predicting CAP-related hospitalization risks, and complications, and mortality. The integration of AI-based risk scores in managing CAP has the potential to enhance the accuracy of predicting patients at higher risk, facilitating timely intervention and resource allocation. Moreover, AI algorithms reduce variability associated with subjective clinical judgment, promoting consistency in decision-making, and provide real-time risk assessments, aiding in the dynamic management of patients with CAP. SUMMARY: The development and implementation of AI-tools for hospitalization in CAP represent a transformative approach to improving patient outcomes. The integration of AI into healthcare has the potential to revolutionize the way we identify and manage individuals at risk of severe outcomes, ultimately leading to more efficient resource utilization and better overall patient care.

First report of Acinetobacter pittii acute community-acquired pneumonia in an immunocompetent patient in France following a heat wave.

BACKGROUND: In recent years, Acinetobacter baumannii-calcoaceticus complex (ABC) infections have attracted attention, mainly because of the impact of carbapenem-resistant isolates in hospital-acquired infections. However, acute community-acquired ABC infections are not uncommon in warm and humid countries, where they are responsible for community-acquired infections with specific clinical features. To date, such infection has not been reported in France. CASE PRESENTATION: We report the case of a 55-year-old non-immunocompromised patient living in France with no known risk factors for community-acquired ABC infections who presented pneumonia with bloodstream infection due to wild-type A. pittii. The outcome was favorable after 7 days of antibiotic treatment with cefepime. We confirmed bacterial identification with whole-genome sequencing, and we examined the A. pitii core-genome phylogeny for genomic clusters. CONCLUSIONS: This situation is uncommon in Europe and occurred after a heat wave in France with temperatures above 38 °C. Herein, we discuss the possibility that this pneumonia may be emerging in the current context of global warming.

Microbiology of Severe Community-Acquired Pneumonia and the Role of Rapid Molecular Techniques.

The microbiology of severe community acquired pneumonia (SCAP) has implications on management, clinical outcomes and public health policy. Therefore, knowledge of the etiologies of SCAP and methods to identify these microorganisms is key. Bacteria including Streptococcus pneumoniae, Staphylococcus aureus and Enterobacteriaceae continue to be important causes of SCAP. Viruses remain the most commonly identified etiology of SCAP. Atypical organisms are also important etiologies of SCAP and are critical to identify for public health. With the increased number of immunocompromised individuals, less common pathogens may also be found as the causative agent of SCAP. Traditional diagnostic tests, including semi-quantitative respiratory cultures, blood cultures and urinary antigens continue to hold an important role in the evaluation of patients with SCAP. Many of the limitations of the aforementioned tests are addressed by rapid, molecular diagnostic tests. Molecular diagnostics utilize culture-independent technology to identify species-specific genetic sequences. These tests are often semi-automated and provide results within hours, which provides an opportunity for expedient antibiotic stewardship. The existing literature suggests molecular diagnostic techniques may improve antibiotic stewardship in CAP, and future research should investigate optimal methods for implementation of these assays into clinical practice.

Biomarkers: Are They Useful in Severe Community-Acquired Pneumonia?

Community acquired pneumonia (CAP) is a prevalent infectious disease often requiring hospitalization, although its diagnosis remains challenging as there is no gold standard test. In severe CAP, clinical and radiologic criteria have poor sensitivity and specificity, and microbiologic documentation is usually delayed and obtained in less than half of sCAP patients. Biomarkers could be an alternative for diagnosis, treatment monitoring and establish resolution. Beyond the existing evidence about biomarkers as an adjunct diagnostic tool, most evidence comes from studies including CAP patients in primary care or emergency departments, and not only sCAP patients. Ideally, biomarkers used in combination with signs, symptoms, and radiological findings can improve clinical judgment to confirm or rule out CAP diagnosis, and may be valuable adjunctive tools for risk stratification, differentiate viral pneumonia and monitoring the course of CAP. While no single biomarker has emerged as an ideal one, CRP and PCT have gathered the most evidence. Overall, biomarkers offer valuable information and can enhance clinical decision-making in the management of CAP, but further research and validation are needed to establish their optimal use and clinical utility.

Influenza and Viral Pneumonia.

Influenza and other respiratory viruses are commonly identified in patients with community-acquired pneumonia, hospital-acquired pneumonia, and in immunocompromised patients with pneumonia. Clinically, it is difficult to differentiate viral from bacterial pneumonia. Similarly, the radiological findings of viral infection are in general nonspecific. The advent of polymerase chain reaction testing has enormously facilitated the identification of respiratory viruses, which has important implications for infection control measures and treatment. Currently, treatment options for patients with viral infection are limited but there is ongoing research on the development and clinical testing of new treatment regimens and strategies.

The Role of Biomarkers in the Diagnosis and Management of Pneumonia.

Biomarkers are used in the diagnosis, severity determination, and prognosis for patients with community-acquired pneumonia (CAP). Selected biomarkers may indicate a bacterial infection and need for antibiotic therapy (C-reactive protein, procalcitonin, soluble triggering receptor expressed on myeloid cells). Biomarkers can differentiate CAP patients who require hospital admission and severe CAP requiring intensive care unit admission. Biomarker-guided antibiotic therapy may limit antibiotic exposure without compromising outcome and thus improve antibiotic stewardship. The authors discuss the role of biomarkers in diagnosing, determining severity, defining the prognosis, and limiting antibiotic exposure in CAP and ventilator-associated pneumonia patients.

Risk factors and predicting nomogram for the clinical deterioration of non-severe community-acquired pneumonia.

BACKGROUND: Currently, there remains insufficient focus on non-severe community-acquired pneumonia (CAP) patients who are at risk of clinical deterioration, and there is also a dearth of research on the related risk factors. Early recognition of hospitalized patients at risk of clinical deterioration will be beneficial for their clinical management. METHOD: A retrospective study was conducted in The First Affiliated Hospital of Wenzhou Medical University, China, spanning from January 1, 2018 to April 30, 2022, and involving a total of 1,632 non-severe CAP patients. Based on whether their condition worsened within 72 h of admission, patients were divided into a clinical deterioration group and a non-clinical deterioration group. Additionally, all patients were randomly assigned to a training set containing 75% of patients and a validation set containing 25% of patients. In the training set, risk factors for clinical deterioration in patients with non-severe CAP were identified by using LASSO regression analysis and multivariate logistic regression analysis. A nomogram was developed based on identified risk factors. The effectiveness of the nomogram in both the training and validation sets was assessed using Receiver Operating Characteristic (ROC) curves, calibration curves, and decision curve analysis (DCA). RESULTS: Age, body mass index (BMI), body temperature, cardiovascular comorbidity, respiratory rate, LDH level, lymphocyte count and D-dimer level were identified as risk factors associated with the clinical deterioration of non-severe CAP within 72 h of admission. The area under curve (AUC) value of the nomogram was 0.78 (95% CI: 0.74-0.82) in the training set and 0.75 (95% CI: 0.67-0.83) in the validation set. Furthermore, the calibration curves for both the training and validation sets indicated that the predicted probability of clinical deterioration aligned with the actual probability. Additionally, DCA revealed clinical utility for the nomogram at a specific threshold probability. CONCLUSION: The study successfully identified the risk factors linked to the clinical deterioration of non-severe CAP and constructed a nomogram for predicting the probability of deterioration. The nomogram demonstrated favorable predictive performance and has the potential to aid in the early identification and management of non-severe CAP patients at elevated risk of deterioration.

Multi-omics analysis reveals overactive inflammation and dysregulated metabolism in severe community-acquired pneumonia patients.

BACKGROUND: Severe community-acquired pneumonia (S-CAP) is a public health threat, making it essential to identify novel biomarkers and investigate the underlying mechanisms of disease severity. METHODS: Here, we profiled host responses to S-CAP through proteomics analysis of plasma samples from a cohort of S-CAP patients, non-severe (NS)-CAP patients, diseases controls (DCs), and healthy controls (HCs). Then, typical differentially expressed proteins were then validated by ELISA in an independent cohort. Metabolomics analysis was further performed on both the cohort 1 and cohort 2. Then, the proteomic and metabolomic signatures were compared between the adult and child cohorts to explore the characteristics of severe pneumonia patients. RESULTS: There were clear differences between CAP patients and controls, as well as substantial differences between the S-CAP and NS-CAP. Pathway analysis of changes revealed excessive inflammation, suppressed immunity, and lipid metabolic disorders in S-CAP cases. Interestingly, comparing these signatures between the adult and child cohorts confirmed that overactive inflammation and dysregulated lipid metabolism were common features of S-CAP patients, independent of age. The change proportion of glycerophospholipids, glycerolipids, and sphingolipids were obviously different in the adult and child S-CAP cases. CONCLUSION: The plasma multi-omics profiling revealed that excessive inflammation, suppressed humoral immunity, and disordered metabolism are involved in S-CAP pathogenesis.

Parent and Clinician Views on Not Using Antibiotics for Mild Community-Acquired Pneumonia.

OBJECTIVES: Preschool-aged children with mild community-acquired pneumonia (CAP) routinely receive antibiotics even though most infections are viral. We sought to identify barriers to the implementation of a "no antibiotic" strategy for mild CAP in young children. METHODS: Qualitative study using semistructured interviews conducted in a large pediatric hospital in the United States from January 2021 to July 2021. Parents of young children diagnosed with mild CAP in the previous 3 years and clinicians practicing in outpatient settings (pediatric emergency department, community emergency department, general pediatrics offices) were included. RESULTS: Interviews were conducted with 38 respondents (18 parents, 20 clinicians). No parent heard of the no antibiotic strategy, and parents varied in their support for the approach. Degree of support related to their desire to avoid unnecessary medications, trust in clinicians, the emotional difficulty of caring for a sick child, desire for relief of suffering, willingness to accept the risk of unnecessary antibiotics, and judgment about the child's illness severity. Eleven (55%) clinicians were familiar with guidelines specifying a no antibiotic strategy. They identified challenges in not using antibiotics, including diagnostic uncertainty, consequences of undertreatment, parental expectations, follow-up concerns, and acceptance of the risks of unnecessary antibiotic treatment of many children if it means avoiding adverse outcomes for some children. CONCLUSIONS: Although both parents and clinicians expressed broad support for the judicious use of antibiotics, pneumonia presents stewardship challenges. Interventions will need to consider the emotional, social, and logistical aspects of managing pneumonia, in addition to developing techniques to improve diagnosis.

Is the JRS atypical pneumonia prediction score useful in detecting COVID-19 pneumonia under nursing or healthcare settings?

BACKGROUND: SARS-CoV-2 causes frequent outbreaks in elderly care facilities that meet the criteria for nursing and healthcare-associated pneumonia (NHCAP). We evaluated whether the Japanese Respiratory Society (JRS) atypical pneumonia prediction score could be adapted to the diagnosis of nursing and healthcare acquired COVID-19 (NHA-COVID-19) with pneumonia. METHODS: We analyzed 516 pneumonia patients with NHA-COVID-19 and compared them with 1505 pneumonia patients with community-associated COVID-19 (CA-COVID-19). NHA-COVID-19 patients were divided into six groups; 80 cases had the ancestral strain, 76 cases had the Alfa variant, 30 cases had the Delta variant, 120 cases had the Omicron subvariant BA.1, 53 cases had the Omicron subvariant BA.2, and 157 cases had the Omicron subvariant BA.5. RESULTS: The sensitivities of the diagnosis of atypical pneumonia in patients with NHA-COVID-19 based on four or more predictors were 22.8 % in the ancestral strain group, 32.0 % in the Alfa variant group, 34.5 % in the Delta variant group, 23.1 % in the BA.1 subvariant group, 32.7 % in the BA.2 subvariant group, and 30.4 % in the BA.5 subvariant group. The diagnostic sensitivity for the presumptive diagnosis of atypical pneumonia was significantly lower for NHA-COVID-19 than for CA-COVID-19 (28.2 % vs 64.1 %, p < 0.0001). CONCLUSIONS: Our present study demonstrated that the JRS atypical pneumonia prediction score is not a useful tool in elderly patients even if there is a lot of atypical pneumonia in the NHCAP group. The caution is necessary that JRS atypical pneumonia prediction score was not fully applied to prediction for NHA-COVID-19 pneumonia.

Usefulness of a predictive model to hospitalize patients with low-risk community-acquired pneumonia.

INTRODUCTION: A high proportion of patients with low-risk community-acquired pneumonia (CAP) (classes I-III of the Pneumonia Severity Index) are hospitalized. The purpose of this study was to determine whether validated severity scales are used in clinical practice to make admission decisions, identify the variables that influence this decision, and evaluate the potential predictive value of these variables. MATERIALS AND METHODS: A prospective, observational study of patients ≥ 18 years of age with a diagnosis of low-risk CAP hospitalized or referred from the Emergency Department to outpatient consultations. A multivariate logistic regression predictive model was built to predict the decision to hospitalize a patient. RESULTS: The study population was composed of 1,208 patients (806 inpatients and 402 outpatients). The severity of CAP was estimated in 250 patients (20.7%). The factors that determined hospitalization were "abnormal findings in complementary studies" (643/806: 79.8%; due to respiratory failure in 443 patients) and "signs of clinical deterioration" [64/806 (7.9%): hypotension (16/64, 25%); hemoptoic expectoration (12/64, 18.8%); tachypnea (10/64, 15.6%)]. In total, ambulatory management was not contraindicated in 24.7% of hospitalized patients (199). The predictive model built to decide about hospitalization had a good power of discrimination (AUC 0.876; 95%CI: 0.855-0.897). CONCLUSIONS: Scales are rarely used to estimate the severity of CAP at the emergency department. The decision to hospitalize or not a patient largely depends on the clinical experience of the physician. Our predictive model showed a good power to discriminate the patients who required hospitalization. Further studies are warranted to validate these results.

Association between the Timing of Urinary Antigen Testing and Outcomes in Legionella Pneumonia Patients: A Nationwide Database Study.

Objective Recommendations on the timing of Legionella urinary antigen tests for community-acquired pneumonia patients differ among guidelines in Japan, the United States, and European nations. We therefore evaluated the association between the timing of urinary antigen tests and in-hospital mortality in patients with Legionella pneumonia. Methods We conducted a retrospective cohort study using the Diagnosis Procedure Combination database, a nationwide database of acute care inpatients in Japan. Patients who underwent Legionella urinary antigen tests on the day of admission formed the tested group. Patients who were tested on day 2 of admission or later or were unexamined formed the control group. We performed a propensity score matching analysis to compare in-hospital mortality, length of hospital stay and duration of antibiotics use between the two groups. Results Of the 9,254 eligible patients, 6,933 were included in the tested group. One-to-one propensity score matching generated 1,945 pairs. The tested group had a significantly lower 30-day in-hospital mortality than the control group (5.7 vs. 7.7%; odds ratio, 0.72; 95% confidence intervals, 0.55-0.95; p=0.020). The tested group also showed a significantly shorter length of stay and duration of antibiotics use than the control group. Conclusion Urine antigen testing upon admission was associated with better outcomes in patients with Legionella pneumonia. Urine antigen tests upon admission may be recommended for all patients with severe community-acquired pneumonia.

Evaluation and clinical practice of pathogens and antimicrobial resistance genes of BioFire FilmArray Pneumonia panel in lower respiratory tract infections.

BACKGROUND: Existing panels for lower respiratory tract infections (LRTIs) are slow and lack quantification of important pathogens and antimicrobial resistance, which are not solely responsible for their complex etiology and antibiotic resistance. BioFire FilmArray Pneumonia (PN) panels may provide rapid information on their etiology. METHODS: The bronchoalveolar lavage fluid of 187 patients with LRTIs was simultaneously analyzed using a PN panel and cultivation, and the impact of the PN panel on clinical practice was assessed. The primary endpoint was to compare the consistency between the PN panel and conventional microbiology in terms of etiology and drug resistance, as well as to explore the clinical significance of the PN panel. The secondary endpoint was pathogen detection using the PN panel in patients with community-acquired pneumonia (CAP) or hospital-acquired pneumonia (HAP). RESULTS: Fifty-seven patients with HAP and 130 with CAP were included. The most common pathogens of HAP were Acinetobacter baumannii and Klebsiella pneumoniae, with the most prevalent antimicrobial resistance (AMR) genes being CTX-M and KPC. For CAP, the most common pathogens were Haemophilus influenzae and Staphylococcus aureus, with the most frequent AMR genes being CTX-M and VIM. Compared with routine bacterial culture, the PN panel demonstrated an 85% combined positive percent agreement (PPA) and 92% negative percent agreement (NPA) for the qualitative identification of 13 bacterial targets. PN detection of bacteria with higher levels of semi-quantitative bacteria was associated with more positive bacterial cultures. Positive concordance between phenotypic resistance and the presence of corresponding AMR determinants was 85%, with 90% positive agreement between CTX-M-type extended-spectrum beta-lactamase gene type and phenotype and 100% agreement for mecA/C and MREJ. The clinical benefit of the PN panel increased by 25.97% compared with traditional cultural tests. CONCLUSION: The bacterial pathogens and AMR identified by the PN panel were in good agreement with conventional cultivation, and the clinical benefit of the PN panel increased by 25.97% compared with traditional detection. Therefore, the PN panel is recommended for patients with CAP or HAP who require prompt pathogen diagnosis and resistance identification.