Clinical Policy: Critical Issues in the Management of Adult Patients Presenting to the Emergency Department With Community-Acquired Pneumonia

Development of a dry powder formulation for pulmonary delivery of azithromycin-loaded nanoparticles

The COVID-19 pandemic has raised concern regarding respiratory system diseases and oral inhalation stands out as an attractive non-invasive route of administration for pulmonary diseases such as chronic bronchitis, cystic fibrosis, COVID-19 and community-acquired pneumonia. In this context, we encapsulated azithromycin in polycaprolactone nanoparticles functionalized with phospholipids rich in dipalmitoylphosphatidylcholine and further produced a fine powder formulation by spray drying with monohydrated lactose. Nanoparticles obtained by the emulsion/solvent diffusion-evaporation technique exhibited a mean hydrodynamic diameter around 195-228 nm with a narrow monomodal size distribution (PdI < 0.2). Nanoparticle dispersions were spray-dried at different inlet temperatures, atomizing air-flow, aspirator air flow, and feed rate, using lactose as a drying aid, resulting in a maximal process yield of 63% and an encapsulation efficiency of 83%. Excipients and the dry powder formulations were characterized in terms of morphology, chemical structure, thermal analyses and particle size by SEM, FTIR, DSC/TGA and laser light diffraction. The results indicated spherical particles with 90% at 4.06 µm or below, an adequate size for pulmonary delivery. Aerosolization performance in a NGI confirmed good aerodynamic properties. Microbiological assays showed that the formulation preserves AZM antimicrobial effect against Staphylococcus aureus and Streptococcus pneumoniae strains, with halos above 18 mm. In addition, no formulation-related cytotoxicity was observed against the human cell lines BEAS-2B (lung epithelial), HUVEC (endothelial) and HFF1 (fibroblasts). Overall, the approach described here allows the production of AZM-PCL nanoparticles incorporated into inhalable microparticles, enabling more efficient pulmonary therapy of lung infections.

Clinical performance of existing diagnostic criteria for pneumonia in older emergency patients: A prospective cohort study

BACKGROUND

Pneumonia accounts for over half a million older adult emergency department (ED) visits annually, but ED pneumonia diagnosis is inaccurate. Geriatric-specific pneumonia diagnostic criteria exist for other settings; no prospective data exist to determine if application in the older adult ED population is feasible. The objective was to prospectively evaluate the utility of four current diagnostic criteria (Loeb; Modified McGeer; Infectious Disease Society of America/American Thoracic Society; American College of Emergency Physicians) in older adult ED patients.

METHODS

This was a prospective, observational cohort study of older adult ED patients ≥65 years of age in two U.S. EDs with suspected pneumonia defined as having chest radiography ordered and treating physician suspicion. The standard we used for defining the presence, absence, or inability to determine a diagnosis of pneumonia diagnosis was expert physician chart adjudication. We report the summary statistics for demographic characteristics and symptoms/exam findings and sensitivity, specificity, and likelihood ratios with 95% confidence intervals of the existing diagnostic criteria. Pre-specified cutoff values of a positive LR >10 and a negative LR <0.3 were considered clinically significant.

RESULTS

Of 135 patients enrolled, 27 had pneumonia by adjudicator review. Typical patient-reported pneumonia symptoms, such as fever (18.5%) and new/worse cough (51.9%), were not consistently present in pneumonia. The IDSA/ATS and ACEP criteria had positive LR >10 and negative LR <0.3; however, all confidence intervals included pre-specified cutoffs.

CONCLUSIONS

Older adults presented to the ED with low frequency of typical pneumonia symptoms. Although existing diagnostic definitions had promising test characteristics, they may not perform well enough for clinical application without refinement.

Initial assessment and management of adults with suspected acute respiratory infection: a rapid evidence synthesis of reviews and cost-effectiveness studies

Background

This work was undertaken to inform a National Institute for Health and Care Excellence guideline on the initial assessment of adults with suspected acute respiratory infection.

Objective

To undertake a rapid evidence synthesis of systematic reviews and cost-effectiveness studies of signs, symptoms and early warning scores for the initial assessment of adults with suspected acute respiratory infection.

Methods

MEDLINE, EMBASE and Cochrane Database of Systematic Reviews were searched for systematic reviews and MEDLINE, EMBASE, EconLit and National Health Service Economic Evaluation Database were searched for cost-effectiveness studies in May 2023. References of relevant studies were checked. Clinical outcomes of interest included escalation of care, antibiotic/antiviral use, time to resolution of symptoms, mortality and health-related quality of life. Risk of bias was assessed using the Risk of Bias in Systematic Reviews tool or the National Institute for Health and Care Excellence economic evaluations checklist. Results were summarised using narrative synthesis.

Results

Nine systematic reviews and one cost-effectiveness study met eligibility criteria. Seven reviews assessed several early warning scores for patients with community- acquired pneumonia, one assessed early warning scores for nursing home-acquired pneumonia and one assessed individual signs/symptoms and the Centor score for patients with sore throat symptoms; all in face-to-face settings. Two good-quality reviews concluded that further research is needed to validate the CRB-65 in primary care/community settings. One also concluded that further research is needed on the Pneumonia Severity Index in community settings; however, the Pneumonia Severity Index requires data from tests not routinely conducted in community settings. One good-quality review concluded that National Early Warning Score appears to be useful in an emergency department/acute medical setting. One review (unclear quality) concluded that the Pneumonia Severity Index and CURB-65 appear useful in an emergency department setting. Two poor-quality reviews concluded that early warning scores can support clinical judgement and one poor-quality review found numerous problems with using early warning scores in a nursing home setting. A good-quality review concluded that individual signs and symptoms have a modest ability to diagnose streptococcal pharyngitis, and that the Centor score can enhance appropriate prescribing of antibiotics. The cost-effectiveness study assessed clinical scores and rapid antigen detection tests for sore throat, compared to delayed antibiotic prescribing. The study concluded that the clinical score is a cost-effective approach when compared to delayed prescribing and rapid antigen testing.

Conclusions

Several early warning scores have been evaluated in adults with suspected acute respiratory infection, mainly the CRB-65, CURB-65 and Pneumonia Severity Index in patients with community-acquired pneumonia. The evidence was insufficient to determine what triage strategies avoid serious illness. Some early warning scores (CURB-65, Pneumonia Severity Index and National Early Warning Score) appear to be useful in an emergency department/acute medical setting; however, further research is required to validate the CRB-65 and Pneumonia Severity Index in primary care/community settings. The economic evidence indicated that clinical scores may be a cost-effective approach to triage patients compared with delayed prescribing.

Future work and limitations

Only systematic reviews were eligible for inclusion in the synthesis of clinical evidence. There was a great deal of overlap in the primary studies included in the reviews, many of which had significant limitations. No studies were undertaken in remote settings (e.g. NHS 111). Only one cost-effectiveness study was identified, with limited applicability to the review question.

Funding

This article presents independent research funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme as award number NIHR159945.

Advancements in the Management of Severe Community-Acquired Pneumonia: A Comprehensive Narrative Review

Pneumonia, classified as a lower respiratory tract illness, affects different parts of the bronchial system as well as alveoli and can present with varying severities depending on co-morbidities and causative pathogens. It can be broadly classified using the setting in which it was acquired, namely the community or hospital setting, the former being more common and spreading through person-to-person droplet transmission. Community-acquired pneumonia (CAP) is currently the fourth leading cause of death worldwide, and its high mortality makes continual insight into the management of the condition worthwhile. This review explores the literature specifically for severe CAP (sCAP) and delves into the diagnosis, various modalities of treatment, and management of the condition. This condition can be defined as pneumonia requiring mechanical ventilation in the ICU and/or presenting with sepsis and organ failure due to pneumonia. The disease process is characterized by inflammation of the lung parenchyma, initiated by a combination of pathogens and lowered local defenses. Acute diagnosis of the condition is vital in reducing negative patient outcomes, namely through clinical presentation, blood/sputum cultures, imaging modalities such as computed tomography scan, and inflammatory markers, identifying common causative pathogens such as Streptococcus pneumoniae, rhinovirus, Legionella, and viral influenza. Pathogens such as Escherichia coli should also be investigated in patients with chronic obstructive pulmonary disease. The mainstay of treating sCAP includes rapid ICU admission once a diagnosis has been confirmed, initiating sepsis protocol, and treatment with combined empiric antibiotic regimens consisting of beta-lactams and macrolides. Corticosteroid use alongside antibiotics shows promise in reducing inflammation, but its use has to be judged on a case-by-case basis. New drugs such as omadacycline, delafloxacin, and zabofloxacin have shown valid evidence for the treatment of resistant causative organisms. The main guidelines for preventing sCAP include maintaining a healthy lifestyle, and annual pneumococcal and influenza vaccines are recommended for the most vulnerable patient groups, such as those with COPD and immunosuppression.

A 29-MRNA HOST RESPONSE WHOLE-BLOOD SIGNATURE IMPROVES PREDICTION OF 28-DAY MORTALITY AND 7-DAY INTENSIVE CARE UNIT CARE IN ADULTS PRESENTING TO THE EMERGENCY DEPARTMENT WITH SUSPECTED ACUTE INFECTION AND/OR SEPSIS

ABSTRACT

Background: Risk stratification of emergency department patients with suspected acute infections and/or suspected sepsis remains challenging. We prospectively validated a 29-messenger RNA host response classifier for predicting severity in these patients. Methods: We enrolled adults presenting with suspected acute infections and at least one vital sign abnormality to six emergency departments in Greece. Twenty-nine target host RNAs were quantified on NanoString nCounter and analyzed with the Inflammatix Severity 2 (IMX-SEV-2) classifier to determine risk scores as low, moderate, and high severity. Performance of IMX-SEV-2 for prediction of 28-day mortality was compared with that of lactate, procalcitonin, and quick sequential organ failure assessment (qSOFA). Results: A total of 397 individuals were enrolled; 38 individuals (9.6%) died within 28 days. Inflammatix Severity 2 classifier predicted 28-day mortality with an area under the receiver operator characteristics curve of 0.82 (95% confidence interval [CI], 0.74-0.90) compared with lactate, 0.66 (95% CI, 0.54-0.77); procalcitonin, 0.67 (95% CI, 0.57-0.78); and qSOFA, 0.81 (95% CI, 0.72-0.89). Combining qSOFA with IMX-SEV-2 improved prognostic accuracy from 0.81 to 0.89 (95% CI, 0.82-0.96). The high-severity (rule-in) interpretation band of IMX-SEV-2 demonstrated 96.9% specificity for predicting 28-day mortality, whereas the low-severity (rule-out) band had a sensitivity of 78.9%. Similarly, IMX-SEV-2 alone accurately predicted the need for day-7 intensive care unit care and further boosted overall accuracy when combined with qSOFA. Conclusions: Inflammatix Severity 2 classifier predicted 28-day mortality and 7-day intensive care unit care with high accuracy and boosted the accuracy of clinical scores when used in combination.

Real-time interactive artificial intelligence of things-based prediction for adverse outcomes in adult patients with pneumonia in the emergency department

BACKGROUND

Artificial intelligence of things (AIoT) may be a solution for predicting adverse outcomes in emergency department (ED) patients with pneumonia; however, this issue remains unclear. Therefore, we conducted this study to clarify it.

METHODS

We identified 52,626 adult ED patients with pneumonia from three hospitals between 2010 and 2019 for this study. Thirty-three feature variables from electronic medical records were used to construct an artificial intelligence (AI) model to predict sepsis or septic shock, respiratory failure, and mortality. After comparisons of the predictive accuracies among logistic regression, random forest, support-vector machine (SVM), light gradient boosting machine (LightGBM), multilayer perceptron (MLP), and eXtreme Gradient Boosting (XGBoost), we selected the best one to build the model. We further combined the AI model with the Internet of things as AIoT, added an interactive mode, and implemented it in the hospital information system to assist clinicians with decision making in real time. We also compared the AIoT-based model with the confusion-urea-respiratory rate-blood pressure-65 (CURB-65) and pneumonia severity index (PSI) for predicting mortality.

RESULTS

The best AI algorithms were random forest for sepsis or septic shock (area under the curve [AUC] = 0.781), LightGBM for respiratory failure (AUC = 0.847), and mortality (AUC = 0.835). The AIoT-based model represented better performance than CURB-65 and PSI indicators for predicting mortality (0.835 vs. 0.681 and 0.835 vs. 0.728).

CONCLUSIONS

A real-time interactive AIoT-based model might be a better tool for predicting adverse outcomes in ED patients with pneumonia. Further validation in other populations is warranted.