Severe community-acquired pneumonia. Epidemiology and prognostic factors

Current Diagnostic Techniques for Pneumonia: A Scoping Review

Community-acquired pneumonia is one of the most lethal infectious diseases, especially for infants and the elderly. Given the variety of causative agents, the accurate early detection of pneumonia is an active research area. To the best of our knowledge, scoping reviews on diagnostic techniques for pneumonia are lacking. In this scoping review, three major electronic databases were searched and the resulting research was screened. We categorized these diagnostic techniques into four classes (i.e., lab-based methods, imaging-based techniques, acoustic-based techniques, and physiological-measurement-based techniques) and summarized their recent applications. Major research has been skewed towards imaging-based techniques, especially after COVID-19. Currently, chest X-rays and blood tests are the most common tools in the clinical setting to establish a diagnosis; however, there is a need to look for safe, non-invasive, and more rapid techniques for diagnosis. Recently, some non-invasive techniques based on wearable sensors achieved reasonable diagnostic accuracy that could open a new chapter for future applications. Consequently, further research and technology development are still needed for pneumonia diagnosis using non-invasive physiological parameters to attain a better point of care for pneumonia patients.

Measuring the prevalence of aspiration pneumonia in view of improving the relevance of antibiotic prescription of antibiotics: A retrospective, observational study

PURPOSE

Aspiration pneumonia (AP) has significant incidence and impact on mortality. However, data about clinical diagnosis criteria are scarce. We aimed to evaluate according to predefined criteria the prevalence of true AP and its impact on antibiotic stewardship.

METHODS

Retrospective study of patients whose main diagnosis was AP hospitalized at Amiens University Hospital in 2018. We first defined diagnostic criteria of certainty for pneumonia and aspiration. AP was then classified according to degree of certainty.

RESULTS

Among 862 cases of AP, its diagnosis was certain, likely, probably in excess, certainly in excess or absent in 2 % (n = 17), 3 % (n = 26), 50.5 % (n = 433), 23.1 % (n = 198) and 21.4 % (n = 183) respectively. Irrelevant use of amoxicillin-clavulanic acid and metronidazole was found in 27 % and 13 % of cases, respectively.

CONCLUSIONS

The diagnosis of AP is frequently excessive, and diagnostic tools are urgently needed to improve antibiotic stewardship.

Enhancing pediatric pneumonia diagnosis through masked autoencoders

Pneumonia, an inflammatory lung condition primarily triggered by bacteria, viruses, or fungi, presents distinctive challenges in pediatric cases due to the unique characteristics of the respiratory system and the potential for rapid deterioration. Timely diagnosis is crucial, particularly in children under 5, who have immature immune systems, making them more susceptible to pneumonia. While chest X-rays are indispensable for diagnosis, challenges arise from subtle radiographic findings, varied clinical presentations, and the subjectivity of interpretations, especially in pediatric cases. Deep learning, particularly transfer learning, has shown promise in improving pneumonia diagnosis by leveraging large labeled datasets. However, the scarcity of labeled data for pediatric chest X-rays presents a hurdle in effective model training. To address this challenge, we explore the potential of self-supervised learning, focusing on the Masked Autoencoder (MAE). By pretraining the MAE model on adult chest X-ray images and fine-tuning the pretrained model on a pediatric pneumonia chest X-ray dataset, we aim to overcome data scarcity issues and enhance diagnostic accuracy for pediatric pneumonia. The proposed approach demonstrated competitive performance an AUC of 0.996 and an accuracy of 95.89% in distinguishing between normal and pneumonia. Additionally, the approach exhibited high AUC values (normal: 0.997, bacterial pneumonia: 0.983, viral pneumonia: 0.956) and an accuracy of 93.86% in classifying normal, bacterial pneumonia, and viral pneumonia. This study also investigated the impact of different masking ratios during pretraining and explored the labeled data efficiency of the MAE model, presenting enhanced diagnostic capabilities for pediatric pneumonia.

A Sequent of Gram-Negative Co-Infectome-Induced Acute Respiratory Distress Syndrome Are Potentially Subtle Aggravators Associated to the SARS-CoV-2 Evolution of Virulence

Acute respiratory distress syndrome (ARDS) is one of the major problems in COVID-19 that is not well understood. ARDS is usually complicated by co-infections in hospitals. Although ARDS is inherited by Europeans and Africans, this is not clear for those from the Middle East. There are severe limitations in correlations made between COVID-19, ARDS, co-infectome, and patient demographics. We investigated 298 patients for associations of ARDS, coinfections, and patient demographics on COVID-19 patients' outcomes. Of the 149 patients examined for ARDS during COVID-19, 16 had an incidence with a higher case fatality rate (CFR) of 75.0% compared to those without ARDS (27.0%) (p value = 0.0001). The co-infectome association showed a CFR of 31.3% in co-infected patients; meanwhile, only 4.8% of those without co-infections (p value = 0.01) died. The major bacteria were Acinetobacter baumannii and Escherichia coli, either alone or in a mixed infection with Klebsiella pneumoniae. Kaplan-Meier survival analysis of COVID-19 patients with and without ARDS revealed a significant difference in the survival time of patients with ARDS (58.8 +/- 2.7 days) and without ARDS (41.9 +/- 1.8 days) (p value = 0.0002). These findings prove that increased hospital time was risky for co-infectome-induced SDRS later on. This also explained that while empiric therapy and lethal ventilations delayed the mortality in 75% of patients, they potentially did not help those without co-infection or ARDS who stayed for shorter times. In addition, the age of patients (n = 298) was significantly associated with ARDS (72.9 +/- 8.9) compared to those without it (56.2 +/- 15.1) and was irrespective of gender. However, there were no significant differences neither in the age of admitted patients before COVID-19 (58.5 +/- 15.3) and during COVID-19 (57.2 +/- 15.5) nor in the gender and COVID-19 fatality (p value 0.546). Thus, Gram-negative co-infectome potentially induced fatal ARDS, aggravating the COVID-19 outcome. These findings are important for the specific differential diagnosis of patients with and without ARDS and co-infections. Future vertical investigations on mechanisms of Gram-negative-induced ARDS are imperative since hypervirulent strains are rapidly circulating. This study was limited as it was a single-center study confined to Ha'il hospitals; a large-scale investigation in major national hospitals would gain more insights.

Prevalence of atypical pathogens in patients with severe pneumonia: a systematic review and meta-analysis

OBJECTIVES

We aimed to summarise the prevalence of atypical pathogens in patients with severe pneumonia to understand the prevalence of severe pneumonia caused by atypical pathogens, improve clinical decision-making and guide antibiotic use.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed, Embase, Web of Science and Cochrane Library were searched through November 2022.

ELIGIBILITY CRITERIA

English language studies enrolled consecutive cases of patients diagnosed with severe pneumonia, with complete aetiological analysis.

DATA EXTRACTION AND SYNTHESIS

We conducted literature retrieval on PubMed, Embase, Web of Science and The Cochrane Library to estimate the prevalence of Chlamydia, Mycoplasma and Legionella in patients with severe pneumonia. After double arcsine transformation of the data, a random-effects model was used for meta-analyses to calculate the pooled prevalence of each pathogen. Meta-regression analysis was also used to explore whether the region, different diagnostic method, study population, pneumonia categories or sample size were potential sources of heterogeneity.

RESULTS

We included 75 eligible studies with 18 379 cases of severe pneumonia. The overall prevalence of atypical pneumonia is 8.1% (95% CI 6.3% to 10.1%) In patients with severe pneumonia, the pooled estimated prevalence of Chlamydia, Mycoplasma and Legionella was 1.8% (95% CI 1.0% to 2.9%), 2.8% (95% CI 1.7% to 4.3%) and 4.0% (95% CI 2.8% to 5.3%), respectively. We noted significant heterogeneity in all pooled assessments. Meta-regression showed that the pneumonia category potentially influenced the prevalence rate of Chlamydia. The mean age and the diagnostic method of pathogens were likely moderators for the prevalence of Mycoplasma and Legionella, and contribute to the heterogeneity of their prevalence.

CONCLUSIONS

In severe pneumonia, atypical pathogens are notable causes, especially Legionella. The diagnostic method, regional difference, sample size and other factors contribute to the heterogeneity of prevalence. The estimated prevalence and relative heterogeneity factors can help with microbiological screening, clinical treatment and future research planning.

PROSPERO REGISTRATION NUMBER

CRD42022373950.

Clinical decision-making using an assessment protocol of swallowing function after aspiration pneumonia: a comparative retrospective study

Objective: Aspiration pneumonia is a challenge in Japan, with many elderly citizens; however, there are insufficient experts on swallowing. Non-expert doctors may suspend oral intake for an overly long period because of the fear of further aspiration. We devised and modified an assessment protocol for swallowing function with reference to the Japanese and American practical guidelines for dysphagia. This study aimed to demonstrate clinical decision-making using the protocol by reporting the results of decisions on the safe and timely restart of adequate food intake for patients with aspiration pneumonia. Patients and Methods: This comparative retrospective study included 101 patients hospitalized with aspiration pneumonia between April 2015 and November 2017. We compared the parameters of patients for whom decisions on resumption of oral intake were aided by our protocol against those of patients from the previous year when the protocol was not used. We counted the days until either resumption of oral intake or events of aspiration/choking. Results: The duration of days until oral intake in the two groups was 1.64 ± 2.34 days in the protocol group (56 patients) and 2.09 ± 2.30 days in the control group (45 patients) (P=0.52). The adverse events of aspiration/choking were less frequent in the protocol group (5 vs. 15, odds ratio (OR) 0.32, P<0.001) as compared to the control group. The protocol group showed a significant reduction in aspiration/choking (OR 0.19, P<0.01). Conclusion: Clinical decision-making based on the protocol seems to help non-expert doctors make informed decisions regarding resuming oral intake after aspiration pneumonia.

A Review on Detection of Pneumonia in Chest X-ray Images Using Neural Networks

The health organisation has suffered from the lack of diagnosis support systems and physicians in India. Further, the physicians are struggling to treat many patients, and the hospitals also have the lack of a radiologist especially in rural areas; thus, almost all cases are handled by a single physician, leading to many misdiagnoses. Computer aided diagnostic systems are being developed to address this problem. The current study aimed to review the different methods to detect pneumonia using neural networks and compare their approach and results. For the best comparisons, only papers with the same data set Chest X-ray14 are studied.

The association between empiric antimicrobial therapy and the risk of clinical failure in critically ill patients with aspiration pneumonia

WHAT IS KNOWN AND OBJECT

Aspiration pneumonia is a clinically important infectious process that can result in increased morbidity and mortality. Empiric antimicrobial therapy with activity against anaerobes has been a standard practice based on previous studies, which isolated anaerobes from respiratory cultures. Recent studies have failed to identify anaerobes as causative pathogens, however, these studies did not assess patient outcomes based on the presence or absence of anaerobic coverage.

METHODS

This retrospective cohort study evaluated patients at least 18 years of age requiring mechanical ventilation diagnosed with aspiration pneumonia between 1 October 2020 and 31 July 2021. The primary outcome was the incidence of clinical failure. Secondary outcomes included the time to clinical failure, the incidence of Clostridioides difficile infections and development of multidrug-resistant infections, as well as time on mechanical ventilation and intensive care unit length of stay.

RESULTS

A total of 141 patients were included with 83 patients initially receiving anaerobic coverage and 58 patients treated without anaerobic coverage. There was no difference in the incidence of clinical failure between cohorts (18.1% vs. 22.4%; p = 0.41). There was a statistically significant difference in anaerobic escalations with more escalations in the cohort without anaerobic coverage (0% vs. 20.7%; p < 0.0001). Patients initially treated with drugs with anaerobic activity had a higher incidence of multidrug resistant infections on current admission (7.2% vs. 0%; p = 0.04) and a longer length of intensive care unit stay.

WHAT IS NEW AND CONCLUSION

In critically ill adults with aspiration pneumonia, our study found no difference in clinical failure based on the presence or absence of empiric anaerobic coverage adding to evolving literature suggesting that anaerobic coverage is not routinely warranted in this patient population. Interpretation of the results needs to consider, however, that the retrospective design led to the inclusion of sicker patients in the anaerobic cohort. The frequency of empiric anaerobic coverage demonstrates the need for a prospective randomized control trial to confirm these findings.

Point-of-care application of diaphragmatic ultrasonography in the emergency department for the prediction of development of respiratory failure in community-acquired pneumonia: A pilot study

Background

Early recognition of patients with community-acquired pneumonia (CAP) at risk of poor outcomes is crucial. However, there is no effective assessment tool for predicting the development of respiratory failure in patients with CAP. Diaphragmatic ultrasonography (DUS) is a novel technique developed for evaluating diaphragmatic function via measurements of the diaphragm thickening fraction (DTF) and diaphragm excursion (DE). This study evaluated the accuracy of DUS in predicting the development of respiratory failure in patients with CAP, as well as the feasibility of its use in the emergency department (ED) setting.

Materials and methods

This was a single-center prospective cohort study. We invited all patients with ED aged ≥ 20 years who were diagnosed with CAP of pneumonia severity index (PSI) SIe diagnosed with CAP of pneumonia severe with respiratory failure or septic shock were excluded. Two emergency physicians performed DUS to obtain DTF and DE measurements. Data were collected to calculate PSI, CURB-65 score, and Infectious Diseases Society of America/American Thoracic Society severity criteria. Study endpoints were taken at the development of respiratory failure or 30 days post-ED presentation. Continuous variables were analyzed using T-tests, while categorical variables were analyzed using chi-square tests. Further logistic regression and receiver operating characteristic curve analyses were performed to examine the ability to predict the development of respiratory failure. Intra- and inter-rater reliability was examined with intraclass correlation coefficients (ICCs).

Results

In this study, 13 of 50 patients with CAP enrolled developed respiratory failure. DTF was found to be an independent predictor (OR: 0.939, p = 0.0416). At the optimal cut-off point of 23.95%, DTF had 69.23% of sensitivity, 83.78% of specificity, 88.57% of negative predictive value, and 80% of accuracy. Intra- and inter-rater analysis demonstrated good consistency (intra-rater ICC 0.817, 0.789; inter-rater ICC 0.774, 0.781).

Conclusion

DUS assessment of DTF may reliably predict the development of respiratory failure in patients with CAP presenting to the ED. Patients with DTF > 23.95% may be considered for outpatient management.

Predictive Value of the Pneumonia Severity Score on Mortality due to Aspiration Pneumonia

Objective: Designing an efficient management strategy for aspiration is of high priority in our aging society because of its high incidence. We evaluated the prognostic value of both the A-DROP (age, dehydration, respiratory, disorientation, and pressure) and the modified A-DROP scoring systems (adding respiratory rate and comorbidity to A-DROP) in patients with aspiration pneumonia.Design: This is a retrospective study using electronic medical records at Saitama Medical University (SMU) hospital.Setting: A 965-bed university tertiary medical center in Japan.Participants: Data were extracted from the electronic medical records of patients from SMU hospital.Methods: In-hospital mortality was compared between two groups: (1) those with a 'severe' to 'advanced severe' A-DROP score; and (2) those with a 'low' to 'middle' A-DROP score. Area under the curve (AUC) for mortality for both the A-DROP and modified A-DROP scoring systems were compared.Results: The in-hospital mortality rates for patients with a high and a low A-DROP score were 28.6% and 9.0%, respectively. The mortality rates in the high modified A-DROP score group and in the low modified A-DROP score group were 28.2% and 9.9%, respectively. These differences in the mortality rates between the two groups were statistically significant for both the A-DROP and the modified A-DROP scoring systems. The AUC of the receiver operating characteristics curve for the A-DROP (0.700; 95% confidence interval, 0.608-0.779) was statistically significant.Conclusion: The A-DROP and modified A-DROP scoring systems are associated with in-hospital mortality in patients with aspiration pneumonia. The A-DROP scoring system is easy to use and may be a clinically valuable tool in the management of aspiration pneumonia.

Inhalation Delivery of Host Defense Peptides (HDP) using Nano- Formulation Strategies: A Pragmatic Approach for Therapy of Pulmonary Ailments

Host defense peptides (HDP) are small cationic molecules released by the immune systems of the body, having multidimensional properties including anti-inflammatory, anticancer, antimicrobial and immune-modulatory activity. These molecules gained importance due to their broad-spectrum pharmacological activities, and hence being actively investigated. Presently, respiratory infections represent a major global health problem, and HDP has an enormous potential to be used as an alternative therapeutics against respiratory infections and related inflammatory ailments. Because of their short half-life, protease sensitivity, poor pharmacokinetics, and first-pass metabolism, it is challenging to deliver HDP as such inside the physiological system in a controlled way by conventional delivery systems. Many HDPs are efficacious only at practically high molar-concentrations, which is not convincing for the development of drug regimen due to their intrinsic detrimental effects. To avail the efficacy of HDP in pulmonary diseases, it is essential to deliver an appropriate payload into the targeted site of lungs. Inhalable HDP can be a potentially suitable alternative for various lung disorders including tuberculosis, Cystic fibrosis, Pneumonia, Lung cancer, and others as they are active against resistant microbes and cells and exhibit improved targeting with reduced adverse effects. In this review, we give an overview of the pharmacological efficacy of HDP and deliberate strategies for designing inhalable formulations for enhanced activity and issues related to their clinical implications.

A Prototype QSP Model of the Immune Response to SARS-CoV-2 for Community Development

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic requires the rapid development of efficacious treatments for patients with life-threatening coronavirus disease 2019 (COVID-19). Quantitative systems pharmacology (QSP) models are mathematical representations of pathophysiology for simulating and predicting the effects of existing or putative therapies. The application of model-based approaches, including QSP, have accelerated the development of some novel therapeutics. Nevertheless, the development of disease-scale mechanistic models can be a slow process, often taking years to be validated and considered mature. Furthermore, emerging data may make any QSP model quickly obsolete. We present a prototype QSP model to facilitate further development by the scientific community. The model accounts for the interactions between viral dynamics, the major host immune response mediators and tissue damage and regeneration. The immune response is determined by viral activation of innate and adaptive immune processes that regulate viral clearance and cell damage. The prototype model captures two physiologically relevant outcomes following infection: a "healthy" immune response that appropriately defends against the virus, and an uncontrolled alveolar inflammatory response that is characteristic of acute respiratory distress syndrome. We aim to significantly shorten the typical QSP model development and validation timeline by encouraging community use, testing, and refinement of this prototype model. It is our expectation that the model will be further advanced in an open science approach (i.e., by multiple contributions toward a validated quantitative platform in an open forum), with the ultimate goal of informing and accelerating the development of safe and effective treatment options for patients.

Predicting 30-day mortality of patients with pneumonia in an emergency department setting using machine-learning models

OBJECTIVE

This study aimed to confirm the accuracy of a machine-learning-based model in predicting the 30-day mortality of patients with pneumonia and evaluating whether they were required to be admitted to the intensive care unit (ICU).

METHODS

The study conducted a retrospective analysis of pneumonia patients at an emergency department (ED) in Seoul, Korea, from January 1, 2016 to December 31, 2017. Patients aged 18 years or older with a pneumonia registry designation on their electronic medical record were enrolled. We collected their demographic information, mental status, and laboratory findings. Three models were used: the pre-existing CURB-65 model, and the CURB-RF and Extensive CURB-RF models, which were machine-learning models that used a random forest algorithm. The primary outcomes were ICU admission from the ED or 30-day mortality. Receiver operating characteristic curves were constructed for the models, and the areas under these curves were compared.

RESULTS

Out of the 1,974 pneumonia patients, 1,732 patients were eligible to be included in the study; from these, 473 patients died within 30 days or were initially admitted to the ICU from the ED. The area under receiver operating characteristic curves of CURB-65, CURB-RF, and extensive-CURB-RF were 0.615 (0.614-0.616), 0.701 (0.700-0.702), and 0.844 (0.843-0.845), respectively.

CONCLUSION

The proposed machine-learning models could predict the mortality of patients with pneumonia more accurately than the pre-existing CURB-65 model and can help decide whether the patient should be admitted to the ICU.

Updates on community acquired pneumonia management in the ICU

While the world is grappling with the consequences of a global pandemic related to SARS-CoV-2 causing severe pneumonia, available evidence points to bacterial infection with Streptococcus pneumoniae as the most common cause of severe community acquired pneumonia (SCAP). Rapid diagnostics and molecular testing have improved the identification of co-existent pathogens. However, mortality in patients admitted to ICU remains staggeringly high.

The American Thoracic Society and Infectious Diseases Society of America have updated CAP guidelines to help streamline disease management. The common theme is use of timely, appropriate and adequate antibiotic coverage to decrease mortality and avoid drug resistance. Novel antibiotics have been studied for CAP and extend the choice of therapy, particularly for those who are intolerant of, or not responding to standard treatment, including those who harbor drug resistant pathogens. In this review, we focus on the risk factors, microbiology, site of care decisions and treatment of patients with SCAP.

Influenza epidemiology and risk factors for severe acute respiratory infection in Morocco during the 2016/2017 and 2017/2018 seasons

Introduction

in order to implement an influenza vaccination program for high-risk-groups in Morocco, as recommended by the World Health Organization, an epidemiological study indicating the influenza virus effect in the development of complicated influenza for subjects with co-morbidity was required. The present study aims to evaluate the risk factors for severe acute respiratory infections caused by influenza in risk groups.

Methods

this research is based on the epidemiological and virological surveillance data of severe acute respiratory infections and influenza-like illness during the 2016/2017 and 2017/2018 seasons. It was realized using a retrospective series study with a descriptive and analytical purpose.

Results

the over-recruitment of pediatric cases with a severe acute respiratory infection has been significantly rectified because cases of severe acute respiratory infections under 15 years old in the 2017/2018 season represent only 57.9%, whereas they represented 75.9% of the total cases of severe acute respiratory infections during the 2016/2017 season. The influenza positivity rate has increased globally and specifically by age group, clinical service and co-morbidity. The risk factors considered were significantly associated with hospitalization for influenza-associated severe acute respiratory infections. The multivariate logistic regression analysis considers male sex (OR=2.1), age ≥65 years (OR=5.4), presence of influenza cases in the surroundings (OR=0.1), diabetes (OR=7.5) and chronic respiratory disease (OR=10.9) as risk factors influenza-associated severe acute respiratory infections.

Conclusion

the risk assessment of influenza-associated severe acute respiratory infections in high-risk groups revealed national epidemiological findings, particularly for diabetics and the elderly. An influenza vaccination program for these high-risk-groups becomes much recommended in Morocco.

Health Care-Associated Pneumonia: Is It Still a Useful Concept?

"Health care-associated pneumonia (HCAP) was introduced into guidelines because of concerns about the increasing prevalence of drug-resistant pathogens (DRPs) not covered by standard empirical therapy. We now know that DRPs are very localized phenomena with low rates in most sites. Although HCAP risk factors are associated with a higher mortality, this is driven by comorbidities rather than the pathogens. Empirical coverage of DRPs has generally not resulted in better patient outcomes. A far more nuanced approach must be taken for patients with risk factors for DRPs taking into account the local cause and severity of disease.

Long-Term Mortality and Prognostic Factors in Aspiration Pneumonia

OBJECTIVES

Aspiration pneumonia is a leading cause of death among older patients; however, little is known about the long-term mortality in aspiration pneumonia. The purpose of this study was to evaluate long-term mortality and its associated factors in patients with aspiration pneumonia.

DESIGN

Retrospective cohort study.

SETTING AND PARTICIPANTS

In total, 550 patients with aspiration pneumonia (median age: 78.0 years, 66.4% male) with compatible clinical symptoms and chest computed tomography images were enrolled at a single tertiary center from 2006 to 2016.

MEASURES

The 1-, 3-, and 5-year mortality rates were evaluated for all patients. The prognostic factors for 1-year and 5-year mortality were also evaluated using Cox proportional hazard models.

RESULTS

A total of 441 (80.2%) patients died during a median follow-up of 50.7 weeks. The 1-, 3-, and 5-year mortality rates were 49.0%, 67.1%, and 76.9%, respectively. Multivariate analysis identified 5 risk factors for 1-year mortality of male sex [hazard ratio (HR) 1.533, P = .003], low body mass index (HR 0.934, P = .002), hypoalbuminemia, anemia (0.973, P = .032), and mechanical ventilation (HR 2.052, P < .001), which were also independent prognostic factors for 5-year mortality. During the follow-up period, 133 (24.2%) patients experienced recurrent aspiration pneumonia. However, Kaplan-Meier analysis showed no significant differences in survival curves between patients with single and recurrent aspiration pneumonia (P = .371).

CONCLUSIONS/IMPLICATIONS

Long-term prognosis of aspiration pneumonia was poor as a result of underlying morbidity instead of the aspiration pneumonia itself. Our findings suggest that prognostic indices for patients with aspiration pneumonia including the patient's underlying conditions should be devised.

A case report of community-acquired Pseudomonas aeruginosa pneumonia complicated with MODS in a previously healthy patient and related literature review

Background

Pseudomonas aeruginosa is an unusual pathogen in community-acquired pneumonia, especially in previously healthy adults, but often indicates poor prognosis.

Case presentation

We report a previously healthy patient who developed severe community-acquired pneumonia (CAP) caused by P. aeruginosa. He deteriorated to septic shock and multiple organ dysfunction syndrome (MODS) quickly, complicated by secondary hematogenous central nervous system (CNS) infection. After 1 month of organ support and antipseudomonal therapy, he had significant symptomatic improvement and was discharged from hospital. During treatment, the pathogen developed resistance to carbapenems quickly and the antibiotic regimen was adjusted accordingly.

Conclusions

According to our case and related literature review, we conclude that more attention should be paid to community-acquired Pseudomonas aeruginosa pneumonia, because of its rapid progression and poor prognosis.

Antibacterial treatment of aspiration pneumonia in older people: a systematic review

Background

Aspiration pneumonia is a common problem in older people with high mortality and increasing prevalence.

Objective

The aims of this paper were to systematically review the literature on the antibacterial treatment of aspiration pneumonia in elderly patients and identify the microbiology of aspiration pneumonia.

Materials and methods

EMBASE, MEDLINE, and Cochrane databases were systematically searched for studies that examined the clinical efficacy of antibiotic treatment in elderly patients with aspiration pneumonia. Information on study design, antibiotic treatment, study population, participants, microbiology, clinical outcomes, adverse events, and mortality was recorded.

Results

There were no definitive clinical trials, placebo-controlled trials, or meta-analyses. Of the eight studies selected for inclusion in the review, the majority utilized and/or compared broad-spectrum antibiotics. No specific antibacterial agent had evidence of superior efficacy. Broad-spectrum antibiotics resulted in the emergence of multiresistant organisms. Anaerobic bacteria were infrequently isolated, suggesting a less important role in the pathogenesis of aspiration pneumonia.

Conclusion

There is limited evidence with regard to the use of antibiotics in older patients with aspiration pneumonia. Research providing an evidence base for the treatment of aspiration pneumonia in older people is required.

Post-resection complications: abscesses, empyemas, bronchopleural fistulas

The role of thoracic surgeons in the management of pulmonary infection has evolved over time as the medical treatments have improved. We herein review historical and current management for surgically-treated pulmonary infections-lung abscesses, empyemas, and bronchopleural fistulas. In particular, we review when the surgeons need to be involved for infectious cases, our algorithm/approach to empyemas, and summary of post-operative bronchopleural fistula in tuberculosis cases.

Pneumonia in Patients with Chronic Obstructive Pulmonary Disease

Chronic obstructive pulmonary disease (COPD) is a frequent comorbid condition associated with increased morbidity and mortality. Pneumonia is the most common infectious disease condition. The purpose of this review is to evaluate the impact of pneumonia in patients with COPD. We will evaluate the epidemiology and factors associated with pneumonia. We are discussing the clinical characteristics of COPD that may favor the development of infections conditions such as pneumonia. Over the last 10 years, there is an increased evidence that COPD patients treated with inhaled corticosteroids are at increased risk to develp pneumonia. We will review the avaialbe information as well as the possible mechanism for this events. We also discuss the impact of influenza and pneumococcal vaccination in the prevention of pneumonia in COPD patients.

Guideline for Antibiotic Use in Adults with Community-acquired Pneumonia

Community-acquired pneumonia is common and important infectious disease in adults. This work represents an update to 2009 treatment guideline for community-acquired pneumonia in Korea. The present clinical practice guideline provides revised recommendations on the appropriate diagnosis, treatment, and prevention of community-acquired pneumonia in adults aged 19 years or older, taking into account the current situation regarding community-acquired pneumonia in Korea. This guideline may help reduce the difference in the level of treatment between medical institutions and medical staff, and enable efficient treatment. It may also reduce antibiotic resistance by preventing antibiotic misuse against acute lower respiratory tract infection in Korea.

How to manage Pseudomonas aeruginosa infections

Infections with Pseudomonas aeruginosa have become a real concern in hospital-acquired infections, especially in critically ill and immunocompromised patients. The major problem leading to high mortality lies in the appearance of drug-resistant strains. Therefore, a vast number of approaches to develop novel anti-infectives is currently pursued. Diverse strategies range from killing (new antibiotics) to disarming (antivirulence) the pathogen. In this review, selected aspects of P. aeruginosa antimicrobial resistance and infection management will be addressed. Many studies have been performed to evaluate the risk factors for resistance and the potential consequences on mortality and attributable mortality. The review also looks at the mechanisms associated with resistance – P. aeruginosa is a pathogen presenting a large genome, and it can develop a large number of factors associated with antibiotic resistance involving almost all classes of antibiotics. Clinical approaches to patients with bacteremia, ventilator-associated pneumonia, urinary tract infections and skin soft tissue infections are discussed. Antibiotic combinations are reviewed as well as an analysis of pharmacokinetic and pharmacodynamic parameters to optimize P. aeruginosa treatment. Limitations of current therapies, the potential for alternative drugs and new therapeutic options are also discussed.

Chest CT findings in patients with dysphagia and aspiration: a systematic review

The objective of this systematic review was to characterize chest CT findings in patients with dysphagia and pulmonary aspiration, identifying the characteristics and the methods used. The studies were selected from among those indexed in the Brazilian Virtual Library of Health, LILACS, Indice Bibliográfico Español de Ciencias de la Salud, Medline, Cochrane Library, SciELO, and PubMed databases. The search was carried out between June and July of 2016. Five articles were included and reviewed, all of them carried out in the last five years, published in English, and coming from different countries. The sample size in the selected studies ranged from 43 to 56 patients, with a predominance of adult and elderly subjects. The tomographic findings in patients with dysphagia-related aspiration were varied, including bronchiectasis, bronchial wall thickening, pulmonary nodules, consolidations, pleural effusion, ground-glass attenuation, atelectasis, septal thickening, fibrosis, and air trapping. Evidence suggests that chest CT findings in patients with aspiration are diverse. In this review, it was not possible to establish a consensus that could characterize a pattern of pulmonary aspiration in patients with dysphagia, further studies of the topic being needed.

Early Radiographic and Tomographic Manifestations of Legionnaires' Disease

PURPOSE

Legionnaires' disease (LD) may occur sporadically or in the course of outbreaks, where the typical radiological manifestations of the disease may better be delineated. We took advantage of a rare community-based epidemic of LD (181 patients) that occurred in 2012 in Quebec City, Canada, to describe the radiographic features of LD and compare the its tomographic presentation with that of community-acquired pneumonia caused by common bacteria other than Legionella pneumophila.

METHODS

From the 181 individuals affected in the outbreak, we obtained the chest radiographs of 159 individuals (mean 63 ± 15 years of age) for detailed analysis; 33 patients had a computed tomography (CT) scan performed during the course of their illness. In a case-control study, we compared the CT scans of patients with LD with those of patients who had received a diagnosis of community-acquired pneumonia caused by a pathogen other than Legionella and confirmed by chest CT scan.

RESULTS

Overall, LD most often presented as an airspace consolidation involving 1 of the lower lobes. Pleural effusion and mediastinal adenopathies were apparent only in a minority, whereas no pneumothorax or cavitation was noted. We did not find any significant difference in chest CT scan findings in patients with LD vs those with community-acquired pneumonia from other bacterial origin. No radiological finding was clearly associated with an increased risk of intensive care unit admission or mortality.

CONCLUSIONS

The early radiographic and tomographic manifestations of LD are nonspecific and similar to those found in community-acquired pneumonia from other bacterial origin.

Severe Pneumonia Caused by Legionella pneumophila: Differential Diagnosis and Therapeutic Considerations

Severe legionella pneumonia poses a diagnostic challenge and requires early intervention. Legionnaire's disease can have several presenting signs, symptoms, and laboratory abnormalities that suggest that Legionella pneumophila is the pathogen, but none of these are sufficient to distinguish L pneumophila pneumonia from other respiratory pathogens. L pneumophila is primarily an intracellular pathogen and needs treatment with antibiotics that efficiently enter the intracellular space.

Microbial Etiology of Pneumonia: Epidemiology, Diagnosis and Resistance Patterns

Globally, pneumonia is a serious public health concern and a major cause of mortality and morbidity. Despite advances in antimicrobial therapies, microbiological diagnostic tests and prevention measures, pneumonia remains the main cause of death from infectious disease in the world. An important reason for the increased global mortality is the impact of pneumonia on chronic diseases, along with the increasing age of the population and the virulence factors of the causative microorganism. The increasing number of multidrug-resistant bacteria, difficult-to-treat microorganisms, and the emergence of new pathogens are a major problem for clinicians when deciding antimicrobial therapy. A key factor for managing and effectively guiding appropriate antimicrobial therapy is an understanding of the role of the different causative microorganisms in the etiology of pneumonia, since it has been shown that the adequacy of initial antimicrobial therapy is a key factor for prognosis in pneumonia. Furthermore, broad-spectrum antibiotic therapies are sometimes given until microbiological results are available and de-escalation cannot be performed quickly. This review provides an overview of microbial etiology, resistance patterns, epidemiology and microbial diagnosis of pneumonia.

Prognostic implications of aspiration pneumonia in patients with community acquired pneumonia: A systematic review with meta-analysis

Aspiration pneumonia is thought to be associated with a poor outcome in patients with community acquired pneumonia (CAP). However, there has been no systematic review regarding the impact of aspiration pneumonia on the outcomes in patients with CAP. This review was conducted using the MOOSE guidelines: Patients: patients defined CAP. Exposure: aspiration pneumonia defined as pneumonia in patients who have aspiration risk. Comparison: confirmed pneumonia in patients who were not considered to be at high risk for oral aspiration. Outcomes: mortality, hospital readmission or recurrent pneumonia. Three investigators independently identified published cohort studies from PubMed, CENTRAL database, and EMBASE. Nineteen studies were included for this systematic review. Aspiration pneumonia increased in-hospital mortality (relative risk, 3.62; 95% CI, 2.65–4.96; P < 0.001, seven studies) and 30-day mortality (3.57; 2.18–5.86; P < 0.001, five studies). In contrast, aspiration pneumonia was associated with decreased ICU mortality (relative risk, 0.40; 95% CI, 0.26–0.60; P < 0.00001, four studies). Although there are insufficient data to perform a meta-analysis on long-term mortality, recurrent pneumonia, and hospital readmission, the few reported studies suggest that aspiration pneumonia is also associated with these poor outcomes. In conclusion, aspiration pneumonia was associated with both higher in-hospital and 30-day mortality in patients with CAP outside ICU settings.

Increased risk of community-acquired pneumonia in COPD patients with comorbid cardiovascular disease

Background and objective

COPD patients with community-acquired pneumonia (CAP) have worse clinical outcomes, as compared to those without COPD. Cardiovascular disease (CVD) is a common comorbidity for COPD patients. Whether COPD with comorbid CVD will increase the risk of CAP is not well investigated. The incidence and factors associated with CAP in COPD patients with and without CVD were analyzed.

Methods

The medical records of patients with newly diagnosed COPD between 2007 and 2010 were reviewed. The patients’ characteristics, medical history of CVD, occurrence of CAP, and type of medication were recorded. Kaplan–Meier curves were used to assess the differences in cumulative incidence of CAP. Cox’s proportional hazards regression model was used to determine the adjusted hazard ratios with 95% confidence intervals in relation to factors associated with CAP in COPD patients with and without CVD.

Results

Among 2,440 patients, 475 patients (19.5%) developed CAP during the follow-up period. COPD patients who developed CAP were significantly older, had lower forced expiratory volume in 1 second, frequent severe exacerbation and comorbid CVD, as well as received inhaled corticosteroid (ICS)-containing therapy than those without CAP. The cumulative incidence of CAP was higher in COPD patients with CVD compared to those without CVD. Patients who received ICS-containing therapy had significantly increased risk of developing CAP compared to those who did not.

Conclusion

For patients with COPD, comorbid CVD is an independent risk factor for developing CAP. ICS-containing therapy may increase the risk of CAP among COPD patients.

Prognostic value of on admission arterial PCO2 in hospitalized patients with community-acquired pneumonia

BACKGROUND

There is little data about the correlation between the outcome of community acquired pneumonia (CAP) and the hypercapnic type respiratory failure. In this study we prospectively investigated the prognostic significance of first arterial CO₂ tension in patients hospitalized with CAP.

METHODS

In this prospective study patients with CAP, admitted to a general hospital were included. PaCO₂ was measured for each subject in an arterial blood sample drawn in the first 2 hours and its correlations with three major outcomes were evaluated: intensive care unit (ICU) admission, duration of admission and mortality in 30 days.

RESULTS

A total of 114 patients (mean age: 60.9±18.3; male: 51.8%) diagnosed with CAP were included. Significant relationship was not found between PaCO₂ and mortality (P=0.544) or ICU admission (P=0.863). However advanced age, associated CHF, high BUN levels, high CURB-65 scores, associated pleural effusion in chest X-ray and being admitted to the ICU (P=0.012, 0.004, 0.003, <0.001, 0.045 and <0.001 respectively) were all significant prognostic factors of higher mortality risks. Prognostic factors for ICU admission were a history of malignancy (P=0.004), higher CURB-65 (P<0.001) scores and concomitant pleural effusion (P=0.028) in chest X-ray. Hypercapnic patients hospitalized for longer duration compared with normocapnic subjects. Furthermore, patients with lower pH (P=0.041) and pleural effusions (P=0.002) were hospitalized longer than the others.

CONCLUSIONS

There was less prominent prognostic value regarding on-admission PaCO₂ in comparison to other factors such as CURB-65. Considering the inconsistent results of surveys conducted on prognostic value of PaCO₂ for CAP outcomes, further investigations are required to reach a consensus on this matter.

Community Acquired Pneumonia in Internal Medicine: A One-Year Retrospective Study Based on Pneumonia Severity Index

Community acquired pneumonia (CAP) represents the sixth cause of death and the first cause of death for an infectious disease in the USA. The aim of the present study is to evaluate how CAP is managed in a hospital setting, with particular attention to the wards of internal medicine, compared to the recommendations based and validated PSI (Pneumonia Severity Index). 42 subjects were included in the study, 25 males and 17 females. According to the PSI, nine (21%) patients were classified in class I, two (5%) in class II, ten (24%) in class III, fifteen (36%) in class IV and six (14%) in class V. Three patients died during the stay in the hospital (2 males and 1 female), all in the highest PSI class (V). According to the criteria used to evaluate the adequacy of the admission to the hospital, twentyeight patients were classified in the HRG, with an appropriate admission, whilst fourteen (33%) were in the LRG, with an inappropriate admission to the hospital. The data of the study confirm the validity of a PSI based strategy for the management of CAP since admittance to the hospital. This approach is not yet widely implemented in Italy, and a better dialogue between hospital and health system representatives would be convenient, to reduce costs and ensure the safety of patients affected by CAP.

Mid-regional proadrenomedullin: An early marker of response in critically ill patients with severe community-acquired pneumonia?

BACKGROUND

Mid-regional proadrenomedullin (MR-proADM) is a novel biomarker with potential prognostic utility in patients with community-acquired pneumonia (CAP).

PURPOSE

To evaluate the value of MR-proADM levels at ICU admission for further severity stratification and outcome prediction, and its kinetics as an early predictor of response in severe CAP (SCAP).

MATERIALS AND METHODS

Prospective, single-center, cohort study of 19 SCAP patients admitted to the ICU within 12h after the first antibiotic dose.

RESULTS

At ICU admission median MR-proADM was 3.58nmol/l (IQR: 2.83-10.00). No significant association was found between its serum levels at admission and severity assessed by SAPS II (Spearman's correlation=0.24, p=0.31) or SOFA score (SOFA<10: <3.45nmol/l vs. SOFA≥10: 3.90nmol/l, p=0.74). Hospital and one-year mortality were 26% and 32%, respectively. No significant difference in median MR-proADM serum levels was found between survivors and non-survivors and its accuracy to predict hospital mortality was bad (aROC 0.53). After 48h of antibiotic therapy, MR-proADM decreased in all but 5 patients (median -20%; IQR -56% to +0.1%). Its kinetics measured by the percent change from baseline was a good predictor of clinical response (aROC 0.80). The best discrimination was achieved by classifying patients according to whether MR-proADM decreased or not within 48h. No decrease in MR-proADM serum levels significantly increased the chances of dying independently of general severity (SAPS II-adjusted OR 174; 95% CI 2-15,422; p=0.024).

CONCLUSIONS

In SCAP patients, a decrease in MR-proADM serum levels in the first 48h after ICU admission was a good predictor of clinical response and better outcome.

Community-Acquired Pneumonia Due to Multidrug- and Non-Multidrug-Resistant Pseudomonas aeruginosa

BACKGROUND

Pseudomonas aeruginosa is not a frequent pathogen in community-acquired pneumonia (CAP). However, in patients with severe CAP, P aeruginosa can be the etiology in 1.8% to 8.3% of patients, with a case-fatality rate of 50% to 100%. We describe the prevalence, clinical characteristics, outcomes, and risk factors associated with CAP resulting from multidrug-resistant (MDR) and non-MDR P aeruginosa.

METHODS

Prospective observational study of 2,023 consecutive adult patients with CAP with definitive etiology.

RESULTS

P aeruginosa was found in 77 (4%) of the 2,023 cases with microbial etiology. In 22 (32%) of the 68 cases of P aeruginosa with antibiogram data, the isolates were MDR. Inappropriate therapy was present in 49 (64%) cases of P aeruginosa CAP, including 17/22 (77%) cases of MDR P aeruginosa CAP. Male sex, chronic respiratory disease, C-reactive protein <12.35 mg/dL, and pneumonia severity index risk class IV to V were independently associated with P aeruginosa CAP. Prior antibiotic treatment was more frequent in MDR P aeruginosa CAP compared with non-MDR P aeruginosa (58% vs 29%, P = .029), and was the only risk factor associated with CAP resulting from MDR P aeruginosa. In the multivariate analysis, age ≥65 years, CAP resulting from P aeruginosa, chronic liver disease, neurologic disease, nursing home, criteria of ARDS, acute renal failure, ICU admission, and inappropriate empiric treatment were the factors associated with 30-day mortality.

CONCLUSIONS

P aeruginosa is an individual risk factor associated with mortality in CAP. The risk factors described can help clinicians to suspect P aeruginosa and MDR P aeruginosa.

Sepsis Patient Detection and Monitor Based on Auto-BN

Sepsis is a life-threatening condition caused by an inappropriate immune response to infection, and is a leading cause of elderly death globally. Early recognition of patients and timely antibiotic therapy based on guidelines improve survival rate. Unfortunately, for those patients, it is often detected late because it is too expensive and impractical to perform frequent monitoring for all the elderly. In this paper, we present a risk driven sepsis screening and monitoring framework to shorten the time of onset detection without frequent monitoring of all the elderly. Within this framework, the sepsis ultimate risk of onset probability and mortality is calculated based on a novel temporal probabilistic model named Auto-BN, which consists of time dependent state, state dependent property, and state dependent inference structures. Then, different stages of a patient are encoded into different states, monitoring frequency is encoded into the state dependent property, and screening content is encoded into different state dependent inference structures. In this way, the screening and monitoring frequency and content can be automatically adjusted when encoding the sepsis ultimate risk into the guard of state transition. This allows for flexible manipulation of the tradeoff between screening accuracy and frequency. We evaluate its effectiveness through empirical study, and incorporate it into existing medical guidance system to improve medical healthcare.

High-resolution Computed Tomography Findings in Patients with Pulmonary Nocardiosis

RATIONALE AND OBJECTIVES

Nocardiosis is difficult to diagnose, and the diagnosis is thus frequently delayed. High-resolution computed tomography (HRCT) findings of patients with pulmonary nocardiosis have been documented in few reports. Our study objective was to assess HRCT findings of patients with pulmonary nocardiosis.

MATERIALS AND METHODS

This was a retrospective study of 20 consecutive patients with pulmonary Nocardia infections who underwent HRCT of the chest at our institutions from January 2011 to August 2014. After the exclusion of two patients with concurrent infections, the study group comprised 18 patients (11 men, 7 women; age range, 39-83 years; mean, 67.9 years) with pulmonary Nocardia infections. Parenchymal abnormalities, enlarged lymph nodes, and pleural effusion were evaluated on HRCT.

RESULTS

Underlying conditions included respiratory disease (n = 6, 33.3%), collagen diseases (n = 5, 27.8%), and diabetes mellitus (n = 4, 22.2%). All patients showed abnormal HRCT findings, including the presence of a nodule/mass (n = 17, 94.4%), ground-glass opacity (n = 14, 77.8%), interlobular septal thickening (n = 14, 77.8%), and cavitation (n = 12, 66.7%). Pleural effusion was seen in two patients. There were no cases of lymph node enlargement.

CONCLUSIONS

Among the HRCT findings in patients with pneumonia, a nodule/mass with interlobular septal thickening and/or cavitation are suggestive of pulmonary nocardiosis.

Precision medicine for the treatment of severe pneumonia in intensive care

Despite advances in its management, community-acquired pneumonia (CAP) remains the most important cause of sepsis-related mortality and the reason for many ICU admissions. Severity assessment is the cornerstone of CAP patient management and the attempts to ensure the best site of care and therapy. Survival depends on a combination of host factors (genetic, age, comorbidities, defenses), pathogens (virulence, serotypes) and drugs. To reduce CAP mortality, early adequate antibiotic therapy is fundamental. The use of combination therapy with a macrolide seems to improve the clinical outcome in the subset of patients with high inflammation due to immunomodulation. Guidelines on antibiotic therapy have been associated with beneficial effects, and studies of newer adjunctive drugs have produced promising results. This paper discusses the current state of knowledge regarding of precision medicine and the treatment of severe CAP patients.

Radionuclide Salivagram and Gastroesophageal Reflux Scintigraphy in Pediatric Patients: Targeting Different Types of Pulmonary Aspiration

OBJECTIVE

Both gastroesophageal reflux (GER) scintigraphy and radionuclide salivagram are commonly used in the detection of pulmonary aspiration in pediatric patients. This investigation is to compare the diagnostic value of these 2 imaging methods.

METHODS

This retrospective study included 4186 pediatric patients (aged 1 week to 16 years; mean age, 28 months) who underwent a GER scintigraphy and/or radionuclide salivagram. Detection rate of pulmonary aspiration by the 2 imaging techniques was compared.

RESULTS

The detection rate for pulmonary aspiration in patients undergoing both procedures was 1.9% (5 of 266) for GER scintigraphy and 22.2% (59 of 266) for radionuclide salivagram. Fifty-six of 59 patients with proven aspiration on radionuclide salivagram demonstrated no such findings on GER scintigraphy, whereas 2 of 5 patients with proven aspiration on GER scintigraphy demonstrated no such findings on radionuclide salivagram. In patients who underwent only 1 procedure (either GER scintigraphy or salivagram), the detection rate for pulmonary aspiration was 0.4% (15 of 3551) for GER scintigraphy and 20.3% (75 of 369) for radionuclide salivagram.

CONCLUSIONS

Radionuclide salivagram showed a much higher detection rate for pulmonary aspiration compared with GER scintigraphy. However, this may be related to a significantly higher prevalence of antegrade versus retrograde aspiration in our study population. Our results also suggest that not all episodes of retrograde aspiration can be detected by a radionuclide salivagram, and the requested scan should be tailored to the type of suspected aspiration.

Comparison of clinical characteristics and outcomes between aspiration pneumonia and community-acquired pneumonia in patients with chronic obstructive pulmonary disease

Background

Chronic obstructive pulmonary disease (COPD) patients often have dysphagia through age and several co-morbidities, leading to aspiration pneumonia (AsP). COPD patients also have increased risk of developing community-acquired pneumonia (CAP). Using a national inpatient database in Japan, we aimed to compare clinical characteristics and outcomes between AsP and CAP in COPD patients and to verify the factors that affect in-hospital morality.

Methods

We retrospectively collected data on COPD patients (age ≥40 years) who were admitted for AsP or CAP in 1,165 hospitals across Japan between July 2010 and May 2013. We performed multivariable logistic regression analyses to examine the association of various factors with all-cause in-hospital mortality for AsP and CAP.

Results

Of 87,330 eligible patients, AsP patients were more likely to be older, male and have poorer general condition and more severe pneumonia than those with CAP. In-hospital mortality in the AsP group was 22.7 % and 12.2 % in the CAP group. After adjustment for patient background, AsP patients had significantly higher mortality than CAP patients (adjusted odds ratio, 1.19; 95 % confidence interval, 1.08–1.32). Subgroup analyses showed higher mortality to be associated with male gender, underweight, dyspnea, physical disability, pneumonia severity, and several co-morbidities. Further, older age and worse level of consciousness were associated with higher mortality in the CAP group, whereas those were not associated in the AsP group.

Conclusions

Clinical characteristics differed significantly between AsP and CAP in COPD patients. AsP patients had significantly higher mortality than those with CAP.

Electronic supplementary material

The online version of this article (doi:10.1186/s12890-015-0064-5) contains supplementary material, which is available to authorized users.

Causes of non-adherence to therapeutic guidelines in severe community-acquired pneumonia

OBJECTIVE

To assess the adherence to Infectious Disease Society of America/American Thoracic Society guidelines and the causes of lack of adherence during empirical antibiotic prescription in severe pneumonia in Latin America.

METHODS

A clinical questionnaire was submitted to 36 physicians from Latin America; they were asked to indicate the empirical treatment in two fictitious cases of severe respiratory infection: community-acquired pneumonia and nosocomial pneumonia.

RESULTS

In the case of community acquired pneumonia, 11 prescriptions of 36 (30.6%) were compliant with international guidelines. The causes for non-compliant treatment were monotherapy (16.0%), the unnecessary prescription of broad-spectrum antibiotics (40.0%) and the use of non-recommended antibiotics (44.0%). In the case of nosocomial pneumonia, the rate of adherence to the Infectious Disease Society of America/American Thoracic Society guidelines was 2.8% (1 patient of 36). The reasons for lack of compliance were monotherapy (14.3%) and a lack of dual antibiotic coverage against Pseudomonas aeruginosa (85.7%). If monotherapy with an antipseudomonal antibiotic was considered adequate, the antibiotic treatment would be adequate in 100% of the total prescriptions.

CONCLUSION

The compliance rate with the Infectious Disease Society of America/American Thoracic Society guidelines in the community-acquired pneumonia scenario was 30.6%; the most frequent cause of lack of compliance was the indication of monotherapy. In the case of nosocomial pneumonia, the compliance rate with the guidelines was 2.8%, and the most important cause of non-adherence was lack of combined antipseudomonal therapy. If the use of monotherapy with an antipseudomonal antibiotic was considered the correct option, the treatment would be adequate in 100% of the prescriptions.

Characteristics associated with clinician diagnosis of aspiration pneumonia: a descriptive study of afflicted patients and their outcomes

BACKGROUND

Aspiration pneumonia is a common disease, although less well characterized than other pneumonia syndromes.

OBJECTIVE

We analyzed patient-level covariates associated with clinician-defined aspiration pneumonia.

METHODS

We used the Community-Acquired Pneumonia Organization database, a multicenter, international population of patients with community-acquired pneumonia, using data from 2001 to 2012. Aspiration pneumonia was determined by the treating clinician. We analyzed covariates associated with clinician-defined diagnosis of aspiration pneumonia using logistic regression. We compared aspiration pneumonia patients to propensity-matched cases with nonaspiration pneumonia.

RESULTS

We studied 5185 patients. Four hundred fifty-one of these patients had aspiration pneumonia. Patients with aspiration pneumonia were older, had greater disease severity, and more comorbidities than patients with nonaspiration pneumonia. They were more likely cared for in the intensive care unit (19% vs 13%, P = 0.002), had longer unadjusted hospital length of stay (9 vs 7 days, P < 0.001), and took longer to achieve clinical stability (unadjusted 8 vs 4 days, P < 0.001). Confusion, nursing home residence, and cerebrovascular disease were most associated with clinician diagnosis of aspiration pneumonia (odds ratio: 4.4, 2.9, 2.3, respectively). Unadjusted inpatient mortality was higher (23% vs 9%, P < 0.001). Aspiration pneumonia conferred a 2.3 odds ratio for inpatient mortality after adjusting for age, disease severity, and comorbidities.

CONCLUSIONS

Among pneumonia patients, confusion, nursing home residence, and cerebrovascular disease are associated with a clinician diagnosis of aspiration. Aspiration pneumonia is associated with greater mortality among patients with community-acquired pneumonia, which is not explained by older age, measured indices of severity, or comorbidities.

Decreased serum level of lipoprotein cholesterol is a poor prognostic factor for patients with severe community-acquired pneumonia that required intensive care unit admission

PURPOSE

The purpose of this study is to investigate the prognostic values of the serum levels of lipids in patients with severe community-acquired pneumonia (CAP) that required intensive care unit (ICU) admission.

MATERIALS AND METHODS

Patients who had severe CAP that required ICU admission were included. Serum lipid level was collected on the days 1 and 7 of ICU stay. Clinical outcome, including length of ICU stay, hospital stay, and death, were monitored prospectively.

RESULTS

A total of 40 patients were enrolled in this study. Lower high-density lipoprotein (HDL) and low-density lipoprotein (LDL) were found in nonsurvival group on ICU admission day 7 (survivors vs nonsurvivors; mean HDL, 41.8 vs 13.0 mg/dL, P = .002; LDL, 62.3 vs 30.3 mg/dL, P = 0.006, respectively). High-density lipoprotein cholesterol level of less than or equal to 17 mg/dL on day 7 (odds ratio, 1.23) and LDL cholesterol level of less than or equal to 21 mg/dL on day 7 (odds ratio, 1.10) could be a predictor of hospital mortality. The mean change in levels of HDL cholesterol in nonsurvivors decreased significantly than those in survivors from days 1 to 7 (8.5 vs -17.4 mg/dL, P = .04) but not LDL cholesterol.

CONCLUSIONS

Decreased serum HDL cholesterol level from days 1 to 7 may be of prognostic value.

Current and emerging Legionella diagnostics for laboratory and outbreak investigations

Legionnaires' disease (LD) is an often severe and potentially fatal form of bacterial pneumonia caused by an extensive list of Legionella species. These ubiquitous freshwater and soil inhabitants cause human respiratory disease when amplified in man-made water or cooling systems and their aerosols expose a susceptible population. Treatment of sporadic cases and rapid control of LD outbreaks benefit from swift diagnosis in concert with discriminatory bacterial typing for immediate epidemiological responses. Traditional culture and serology were instrumental in describing disease incidence early in its history; currently, diagnosis of LD relies almost solely on the urinary antigen test, which captures only the dominant species and serogroup, Legionella pneumophila serogroup 1 (Lp1). This has created a diagnostic "blind spot" for LD caused by non-Lp1 strains. This review focuses on historic, current, and emerging technologies that hold promise for increasing LD diagnostic efficiency and detection rates as part of a coherent testing regimen. The importance of cooperation between epidemiologists and laboratorians for a rapid outbreak response is also illustrated in field investigations conducted by the CDC with state and local authorities. Finally, challenges facing health care professionals, building managers, and the public health community in combating LD are highlighted, and potential solutions are discussed.