Tools for outcome prediction in patients with community acquired pneumonia

Cross-Sectional and Longitudinal Associations of Serum LRG1 with Severity and Prognosis Among Adult Community-Acquired Pneumonia Patients

Background

Leucine-rich α-2 glycoprotein 1 (LRG1) is associated with various inflammatory lung diseases. Nevertheless, the connection between LRG1 and adult community-acquired pneumonia (CAP) individuals was still not well understood. Through a prospective cohort study, the correlations of serum LRG1 with severity and prognosis were evaluated in CAP patients.

Methods

The study encompassed 327 patients who received the diagnosis of CAP. We collected fasting venous blood and clinical features. Serum LRG1 was detected by ELISA. CAP severity was assessed using various scoring systems. The prognostic outcomes were observed through follow-up visits.

Results

The level of serum LRG1 at admission was gradually increased with CAP severity scores. Serum LRG1 level shown positive associations with inflammatory indices, including C-reactive protein (CRP), procalcitonin (PCT), and interleukin-6 (IL-6). Linear and logistic regression analyses suggested that serum LRG1 at admission was positively associated with severity scores and the risk of death in CAP patients. Serum LRG1 in combination with CAP severity scores significantly increased the predictive powers for severity and death compared with single serum LRG1 or severity scores.

Conclusion

The study revealed positive connections of serum LRG1 levels with severity and poor prognosis in CAP patients, suggesting LRG1 partakes into the physiological processes of CAP. Serum LRG1 may be regarded as a potential biomarker in predicting the severity and death among CAP patients.

Association of serum interleukin-2 with severity and prognosis in hospitalized patients with community-acquired pneumonia: a prospective cohort study

The prior studies have shown that interleukin-2 (IL-2) exerts important roles in the pathological and physiological processes of lung diseases. However, the role of IL-2 in community-acquired pneumonia (CAP) is still uncertain. Through a prospective cohort study, our research will explore the correlations between serum IL-2 levels and the severity and prognosis in CAP patients. There were 267 CAP patients included. Blood samples were obtained. Serum IL-2 were tested by enzyme-linked immunosorbent assay (ELISA). Demographic traits and clinical characteristics were extracted. Serum IL-2 were gradually elevated with increasing severity scores in CAP patients. Correlation analyses revealed that serum IL-2 were connected with physiological parameters including liver and renal function in CAP patients. According to a logistic regression analysis, serum IL-2 were positively correlated with CAP severity scores. We also tracked the prognostic outcomes of CAP patients. The increased risks of adversely prognostic outcomes, including mechanical ventilation, vasoactive agent usage, ICU admission, death, and longer hospital length, were associated with higher levels of IL-2 at admission. Serum IL-2 at admission were positively associated with severe conditions and poor prognosis among CAP patients, indicated that IL-2 may involve in the initiation and development of CAP. As a result, serum IL-2 may be an available biomarker to guide clinicians in assessing the severity and determining the prognosis of CAP.

Research progress of biomarkers in evaluating the severity and prognostic value of severe pneumonia in children

Pneumonia is a serious and common infectious disease in children. If not treated in time, it may develop into severe pneumonia. Severe pneumonia in children is mainly characterized by hypoxia and acidosis, often accompanied by various complications such as sepsis and multiple organ dysfunction. Severe pneumonia has a rapid onset and progression, and a high mortality rate. Biomarkers assist clinicians in the early diagnosis and treatment of patients by quickly and accurately identifying their conditions and prognostic risks. In this study, common clinical and novel biomarkers of severe pneumonia in children were reviewed, and the application value of biomarkers related to the severity and prognosis of severe pneumonia in children was evaluated to provide help for early identification and precise intervention by clinicians.

Supporting vaccine (co)-administration decisions: Development and validation of a tool for assessing the risk of severe outcomes due to lower respiratory tract infections

OBJECTIVE

To develop and validate a score to predict the 90-day risk of hospitalization/death in patients with low respiratory tract infections (LRTIs) with the aim to support clinical decision making on vaccine (co)-administration.

METHODS

We formed a cohort of patients aged 18 years or older being diagnosed with LRTIs in the period between January 1, 2012 and December 31, 2022. Each patient was followed until occurrence of respiratory-related hospitalization/death up to the end of the study period (December 31, 2022). Along with age and sex, forty determinants were adopted to assemble the respiratory tract infection (RTI)-Health Search (HS) core using the development sub-cohort. The prediction accuracy of the score was therefore assessed in the validation sub-cohort.

RESULTS

We identified 252,319 patients being diagnosed with LRTIs (females: 54.7 %; mean age: 60 (SD:18.1)). When the risk of LRTIs-related hospitalizations/deaths was estimated via RTI-HScore, its predicted value was equal to 1.4 % over a 90-day event horizon. The score showed explained variation and discrimination accuracy were equal to 45 % (95 % CI: 44-47 %) and 81 % (95 % CI: 79-84 %), respectively. The calibration slope did not significantly differ from the unit (p = 0.8314).

CONCLUSIONS

The RTI-HScore was featured by good accuracy for prediction of LRTIs-related complications over a 90-day follow-up. Such a tool might therefore support general practitioners to enhance patients' care by facilitating approaches for (co)-administration of vaccines for respiratory infections through a score-based decision support system.

The value of surfactant protein a in evaluating the severity and prognosis in community-acquired pneumonia patients

BACKGROUND

Previous research has discovered that surfactant protein A (SP-A) is involved in the pathophysiology processes of certain lung illnesses. However, no definitive clinical studies have delved into the function of SP-A in individuals afflicted with community-acquired pneumonia (CAP). A prospective cohort study was used to investigate the relationships between blood SP-A levels and the severity and prognosis among CAP patients.

MATERIALS AND METHODS

This study included 260 patients with CAP. Clinical traits and demographic data were examined during hospitalization. The concentrations of serum SP-A and serum interleukin-6 (IL-6) were determined by enzyme-linked immunosorbent assay (ELISA). In addition, to evaluate the severity of CAP, a variety of scores, including the CURB-65, PSI, SMART-COP, and APACHE II, were employed.

RESULTS

The serum levels of SP-A at admission exhibited a gradual decline as the severity scores of CAP increased. Through Spearman correlation analysis, we observed an association between serum SP-A and some clinical indicators among CAP patients. Furthermore, results from a multiple linear regression model suggested changes in PSI scores (-17.868 scores, 95% CI: -32.743, -2.993) affect serum SP-A more than CURB-65 (-0.547 scores, 95% CI: -0.964, -0.131), SMART-COP (-1.097 scores, 95% CI: -1.889, -0.304) and APACHE II (-3.475 scores, 95% CI: -5.874, -1.075) with age, hypertension, diabetes mellitus, cerebral infarction, coronary heart disease, and bronchitis adjusted. In addition, the prognosis in CAP patients was monitored. Throughout their hospital stay, higher serum levels of SP-A decreased the risks of mechanical ventilation (RR: 0.315; 95% CI: 0.106, 0.937), vasoactive agents (RR: 0.165; 95% CI: 0.034, 0.790), intensive care unit (ICU) admissions (RR: 0.218; 95% CI: 0.066, 0.717) and longer hospital stays (RR: 0.397; 95% CI: 0.167, 0.945).

CONCLUSION

In CAP patients, inverse dose-response correlations exist between serum SP-A levels with severity scores as well as prognosis at admission, suggesting that SP-A may take part in the CAP pathophysiological processes. Moreover, lower serum SP-A on admission is associated with an elevated prognostic risk of mechanical ventilation, the use of vasoactive agents, longer hospital stays, ICU admission, and mortality. Therefore, as a biomarker, SP-A may have the potential to predict the severity and poor prognosis of CAP patients.

Biomarkers in pulmonary infections: a clinical approach

Severe acute respiratory infections, such as community-acquired pneumonia, hospital-acquired pneumonia, and ventilator-associated pneumonia, constitute frequent and lethal pulmonary infections in the intensive care unit (ICU). Despite optimal management with early appropriate empiric antimicrobial therapy and adequate supportive care, mortality remains high, in part attributable to the aging, growing number of comorbidities, and rising rates of multidrug resistance pathogens. Biomarkers have the potential to offer additional information that may further improve the management and outcome of pulmonary infections. Available pathogen-specific biomarkers, for example, Streptococcus pneumoniae urinary antigen test and galactomannan, can be helpful in the microbiologic diagnosis of pulmonary infection in ICU patients, improving the timing and appropriateness of empiric antimicrobial therapy since these tests have a short turnaround time in comparison to classic microbiology. On the other hand, host-response biomarkers, for example, C-reactive protein and procalcitonin, used in conjunction with the clinical data, may be useful in the diagnosis and prediction of pulmonary infections, monitoring the response to treatment, and guiding duration of antimicrobial therapy. The assessment of serial measurements overtime, kinetics of biomarkers, is more informative than a single value. The appropriate utilization of accurate pathogen-specific and host-response biomarkers may benefit clinical decision-making at the bedside and optimize antimicrobial stewardship.

The Role of Biomarkers in Influenza and COVID-19 Community-Acquired Pneumonia in Adults

Pneumonia is a growing problem worldwide and remains an important cause of morbidity, hospitalizations, intensive care unit admission and mortality. Viruses are the causative agents in almost a fourth of cases of community-acquired pneumonia (CAP) in adults, with an important representation of influenza virus and SARS-CoV-2 pneumonia. Moreover, mixed viral and bacterial pneumonia is common and a risk factor for severity of disease. It is critical for clinicians the early identification of the pathogen causing infection to avoid inappropriate antibiotics, as well as to predict clinical outcomes. It has been extensively reported that biomarkers could be useful for these purposes. This review describe current evidence and provide recommendations about the use of biomarkers in influenza and SARS-CoV-2 pneumonia, focusing mainly on procalcitonin (PCT) and C-reactive protein (CRP). Evidence was based on a qualitative analysis of the available scientific literature (meta-analyses, randomized controlled trials, observational studies and clinical guidelines). Both PCT and CRP levels provide valuable information about the prognosis of influenza and SARS-CoV-2 pneumonia. Additionally, PCT levels, considered along with other clinical, radiological and laboratory data, are useful for early diagnosis of mixed viral and bacterial CAP, allowing the proper management of the disease and adequate antibiotics prescription. The authors propose a practical PCT algorithm for clinical decision-making to guide antibiotic initiation in cases of influenza and SARS-CoV-2 pneumonia. Further well-design studies are needed to validate PCT algorithm among these patients and to confirm whether other biomarkers are indeed useful as diagnostic or prognostic tools in viral pneumonia.

Validation of IDSA/ATS Guidelines for ICU Admission in Adults Over 80 Years Old With Community-Acquired Pneumonia

INTRODUCTION

The 2007 IDSA/ATS guidelines for community-acquired pneumonia (CAP) recommended intensive care unit (ICU) admission for adults meeting severe CAP criteria. We aimed to validate the accuracy of IDSA/ATS criteria in patients≥80 years old (very elderly patients, VEP) with CAP.

METHODS

Prospective cohort study of VEP with CAP admitted to three Spanish hospitals between 1996 and 2019. We compared patients who did and did not require ICU admission. We also assessed factors independently associated with ICU admission, as well as the accuracy of severe CAP criteria for ICU admission and mortality. Major criteria include septic shock and invasive mechanical ventilation while minor criteria encompass other variables related to hemodynamics and respiratory insufficiency as well as level of consciousness, renal function, blood parameters indicative of sepsis and body temperature.

RESULTS

Of the 2006 VEP with CAP, 519 (26%) met severe CAP criteria, while 204 (10%) required ICU admission. Concordance between severe CAP criteria and the decision to admit the patient to the ICU occurred in 1591 (79%) cases (k coefficient, 0.33), with a sensitivity of 75% and specificity of 80% in predicting ICU admission. All patients with invasive mechanical ventilation received care in ICUs, while 45 (44%) patients with septic shock-previously stabilized in the emergency room-did not. Thirty-day mortality of ICU-admitted patients with septic shock was lower than that of patients in wards (30% vs. 60%, p=0.013). In contrast, patients with severe CAP and only minor criteria had similar mortality.

CONCLUSIONS

IDSA/ATS criteria for severe CAP predict ICU admission in VEP moderately well. While patients with septic shock and invasive mechanical ventilation warrant ICU admission, severe CAP without major severity criteria in VEP may be acceptably manageable in wards.

Validation of IDSA/ATS Guidelines for ICU Admission in Adults Over 80 Years Old With Community-acquired Pneumonia

INTRODUCTION

The 2007 IDSA/ATS guidelines for community-acquired pneumonia (CAP) recommended intensive care unit (ICU) admission for adults meeting severe CAP criteria. We aimed to validate the accuracy of IDSA/ATS criteria in patients ≥80 years old (very elderly patients, VEP) with CAP.

METHODS

Prospective cohort study of VEP with CAP admitted to three Spanish hospitals between 1996 and 2019. We compared patients who did and did not require ICU admission. We also assessed factors independently associated with ICU admission, as well as the accuracy of severe CAP criteria for ICU admission and mortality. Major criteria include septic shock and invasive mechanical ventilation while minor criteria encompass other variables related to hemodynamics and respiratory insufficiency as well as level of consciousness, renal function, blood parameters indicative of sepsis and body temperature.

RESULTS

Of the 2006 VEP with CAP, 519 (26%) met severe CAP criteria, while 204 (10%) required ICU admission. Concordance between severe CAP criteria and the decision to admit the patient to the ICU occurred in 1591 (79%) cases (k coefficient, 0.33), with a sensitivity of 75% and specificity of 80% in predicting ICU admission. All patients with invasive mechanical ventilation received care in ICUs, while 45 (44%) patients with septic shock-previously stabilized in the emergency room-did not. Thirty-day mortality of ICU-admitted patients with septic shock was lower than that of patients in wards (30% vs. 60%, P=0.013). In contrast, patients with severe CAP and only minor criteria had similar mortality.

CONCLUSIONS

IDSA/ATS criteria for severe CAP predict ICU admission in VEP moderately well. While patients with septic shock and invasive mechanical ventilation warrant ICU admission, severe CAP without major severity criteria in VEP may be acceptably manageable in wards.

Sphingosine-1-phosphate and CRP as potential combination biomarkers in discrimination of COPD with community-acquired pneumonia and acute exacerbation of COPD

Background

 Chronic obstructive pulmonary disease (COPD) is a significant public health concern. The patients with acute exacerbations of COPD (AECOPD) and pneumonia have similar clinical presentations. The use of conventional diagnostic markers, such as complete blood count with differential and C-reactive protein (CRP), is the current mainstream method for differentiating clinically relevant pneumonia from other mimics. However, those conventional methods have suboptimal sensitivity and specificity for patients with a clinical suspicion of infection. The limitations often cause the ambiguity of the initiation of antibiotic treatment. Recently, our pilot study suggested that the patients with pneumonia have significantly higher plasma Sphingosine-1-phosphate (S1P) levels than controls. The initial findings suggest that plasma S1P is a potential biomarker for predicting prognosis in pneumonia. The aim of this study was to evaluate the value of S1P and CRP for discriminating COPD with pneumonia and AECOPD in an Emergency Department (ED) setting.

Methods

 Patients diagnosed with AECOPD or COPD with pneumonia were recruited from the Emergency Department of Wan Fang Hospital. The clinical data, demographics, and blood samples were collected upon ED admission. The concentration of plasma S1P was measured by ELISA.

Results

 Thirty-nine patients with AECOPD and 78 with COPD plus pneumonia were enrolled in this observational study. The levels of blood S1P and CRP were significantly higher in patients with COPD plus CAP compared to those in AE COPD patients. The area under the receiver operator characteristic (ROC) curve for the S1P and CRP for distinguishing between patients with COPD plus CAP and AECOPD is 0.939 (95% CI: 0.894–0.984) and 0.886 (95% CI: 0.826–0.945), whereas the combination of S1P and CRP yielded a value of 0.994 (95% CI: 0.897–1.000). By comparing with CRP or S1P, combining CRP and S1P had significantly higher AUC value for differentiating between the COPD with pneumonia group and the AECOPD group.

Conclusions

Our findings suggest that S1P is a potential diagnostic biomarker in distinguishing COPD with CAP from AECOPD. Additionally, the diagnostic ability of S1P can be improved when used in combination with CRP.

Management of pneumonia in critically ill patients

Severe pneumonia is associated with high mortality (short and long term), as well as pulmonary and extrapulmonary complications. Appropriate diagnosis and early initiation of adequate antimicrobial treatment for severe pneumonia are crucial in improving survival among critically ill patients. Identifying the underlying causative pathogen is also critical for antimicrobial stewardship. However, establishing an etiological diagnosis is challenging in most patients, especially in those with chronic underlying disease; those who received previous antibiotic treatment; and those treated with mechanical ventilation. Furthermore, as antimicrobial therapy must be empiric, national and international guidelines recommend initial antimicrobial treatment according to the location's epidemiology; for patients admitted to the intensive care unit, specific recommendations on disease management are available. Adherence to pneumonia guidelines is associated with better outcomes in severe pneumonia. Yet, the continuing and necessary research on severe pneumonia is expansive, inviting different perspectives on host immunological responses, assessment of illness severity, microbial causes, risk factors for multidrug resistant pathogens, diagnostic tests, and therapeutic options.

Adhesion molecules as diagnostic and severity biomarkers in pediatric community-acquired pneumonia

BACKGROUND

Discrimination of the cases with severe and mild pneumonia is crucial due to the requirement of hospitalization, additional management, and treatment protocols. We aimed to analyze the role of IL6 (Interleukin), IL8, IL10, VCAM-1 (soluble Vascular Cell Adhesion Molecule), and sSELE (soluble E-selectin) in the diagnosis and prognostic evaluation of community-acquired pneumonia (CAP).

METHODS

Pediatric patients with severe pneumonia (SP) were hospitalized and patients with mild disease (MP) were treated in the community. IL6, IL8, IL10, VCAM-1, and sSELE levels of the patients were investigated and compared with the age- and gender-matched healthy subjects.

RESULTS

A total of 113 patients fulfilling the criteria for a diagnosis of CAP were enrolled in the study, 62 (54.8%) of which had SP and 51 (45%) had MP. MP and SP groups were significantly different in terms of IL8, IL10, and sSELE levels. Patients with SP and MP had significantly different WBC, ESR, and CRP values, as well.

CONCLUSIONS

Besides classical acute phase parameters, inflammatory response parameters such as IL6 and VCAM-1 levels may be helpful in diagnosis of pneumonia. In terms of determination of disease severity in pediatric CAP, systemic inflammatory markers like IL8 and IL10 and adhesion molecules like sSELE seem useful in clinical settings.

A Hospital-based Study on the Local Epidemiology of Pneumonia Including the Contribution of Legionella Pneumonia

Background

In real-life practice, only 20% of hospitalised pneumonia cases have an identified etiology. The usage of Legionella urine antigen test (LUAT) in developed nations revolutionised case detection rates. Accordingly, our objectives were to study the microbiological etiology for hospitalised pneumonia patients and the diagnosis of Legionella pneumonia.

Methods

A prospective, observational single-centre study was conducted where all 504 cases that were consecutively admitted for pneumonia were enrolled. Blood and sputum samples obtained were used to identify pathogens using standard microbiological culture methods. The urine samples collected were tested using the Immunocatch^TMLegionella immunochromatographic (ICT) urine antigen test.

Results

A microbiological diagnosis was only achieved in 104 cases (20.6%) and a Gram-negative infection predominance was observed. Culture-positive cases required longer hospitalisation (8.46 days versus 5.53 days; P < 0.001) and the higher usage of antipseudomonal antibiotics (23.1% versus 8.3%; P < 0.001). Only 3 cases (0.6%) were diagnosed with Legionella pneumonia.

Conclusion

The local pathogen distribution is diverse compared to other regions. Culture-negative pneumonia is common and significantly differs from culture-positive pneumonia. Legionella pneumophila serotype 1 is not a common cause of pneumonia and LUAT did not help demystify the cause of culture-negative pneumonia.

Predictive roles of D-dimer for mortality of patients with community-acquired pneumonia: a systematic review and meta-analysis

OBJECTIVE

To explore the predictive roles of D-dimer for the mortality of patients with community-acquired pneumonia (CAP).

METHODS

This was a systematic review and meta-analysis. We searched the following databases: PubMed, EMBASE, Web of Science, Ovid MEDLINE, and Cochrane Library from their inception to July 26, 2020. Studies exploring the relationship between blood D-dimer levels and CAP-related mortality were selected. In this meta-analysis, we calculated mortality rates, sensitivity, specificity, positive likelihood ratios, and negative likelihood ratios.

RESULTS

The search identified 1,073 articles, 8 of which (a total of 2,126 patients) were included in this meta-analysis. The pooled mortality rate of the overall sample was 0.10 (95% CI, 0.08-0.14). The levels of blood D-dimer in the nonsurvivors were significantly higher than those in the survivors (weighted mean difference = 1.03 mg/L [95% CI, 0.81-1.26]; p < 0.00001). The area under the summary ROC curve for the optimal cutoff value of D-dimer as a predictor of mortality was 0.848 (SE = 0.046), and the pooled negative likelihood ratio for D-dimer within the normal range was 0.24 (95% CI, 0.11-0.53).

CONCLUSIONS

Blood D-dimer might be helpful for the initial assessment of mortality risk of patients with CAP. D-dimer levels within the normal range indicate low risk of mortality. Because of the small sample size in our study, our findings should be further explored and validated in future studies with larger sample sizes.

Serum human neutrophil lipocalin: An effective biomarker for diagnosing bacterial infections

BACKGROUND

Human neutrophil lipocalin (HNL) is used as a novel biomarker for infections. However, only a few studies have focused on the usefulness of HNL. The purpose of this study was to evaluate the diagnostic efficiency of HNL for identifying bacterial infections and to compare HNL with procalcitonin (PCT) and C-reactive protein (CRP).

METHODS

Hospital patients with acute infections of bacterial origin (n = 439), viral origin (n = 71), and healthy volunteers (n = 67) were included in the study. The infection status of each patient was verified using microbiological, serological, and PCR testing. Additionally, CRP, HNL, and PCT levels were measured by established methods.

RESULTS

In distinguishing bacterial and viral infections, area under the curve (AUC) analysis showed that, with a value of 0.81 (95% CI, 0.76-0.86), HNL was superior to CRP at 0.73 (0.68-0.79) and PCT at 0.64 (0.58-0.70). Interestingly, the combination of HNL, PCT, and CRP improved the diagnostic potential significantly with an AUC of 0.86 (0.82-0.90, P < 0.05). Furthermore, when comparing different infection site subgroups with healthy patients, HNL levels were higher in all bacterial groups, albeit to widely varying degrees (P < 0.0001), and HNL reached a higher level in bloodstream and abdominal infections. CRP levels showed the same trend as HNL levels. PCT levels were significantly increased in bloodstream infections, abdominal infections, and in bacterial pneumonia (P < 0.0001), while no significant differences were found in soft tissue (P = 0.4378) or urinary tract infections (P = 0.423). There was no difference in HNL and CRP levels between patients with Gram-negative bacterial (GNB) or Gram-positive bacterial infections. However, compared with controls, PCT was only increased in GNB-infected patients.

CONCLUSION

HNL detection can help diagnose patients with infectious diseases, and the diagnostic efficacy of HNL is not affected by the infected site or by pathogenic bacterial species. The combination of HNL, PCT, and CRP has a superior performance at identifying bacterial infections compared with traditional biomarkers.

Community-acquired pneumonia as an emergency condition

PURPOSE OF REVIEW

Despite the improvements in its management, community-acquired pneumonia (CAP) still exhibits high global morbidity and mortality rates, especially in elderly patients. This review focuses on the most recent findings on the epidemiology, cause, diagnosis and management of CAP.

RECENT FINDINGS

There is consistent evidence that the trend in CAP mortality has declined over time. However, the mortality of pneumococcal CAP has not changed in the last two decades, with an increase in the rate of hospitalization and more severe forms of CAP. Streptococcus pneumoniae remains the most frequent cause of CAP in all settings, age groups and regardless of comorbidities. However, the implementation of molecular diagnostic tests in the last years has identified respiratory viruses as a common cause of CAP too. The emergency of multidrug-resistance pathogens is a worldwide concern. An improvement in our ability to promptly identify the causative cause of CAP is required in order to provide pathogen-directed antibiotic therapy, improve antibiotic stewardship programs and implement appropriate vaccine strategies.

SUMMARY

It is time to apply all the knowledge generated in the last decade in order to optimize the management of CAP.

Outpatient management of community-acquired pneumonia

PURPOSE OF REVIEW

The first guidelines on community-acquired pneumonia (CAP) were published in 1993, but since then many of the challenges regarding the outpatient management of CAP persist. These include the difficulty in establishing the initial clinical diagnosis, its risk stratification, which will dictate the place of treatment, the empirical choice of antibiotics, the relative scarcity of novel antibiotics and the importance of knowing local microbiological susceptibility patterns.

RECENT FINDINGS

New molecular biology methods have changed the etiologic perspective of CAP, especially the contribution of virus. Lung ultrasound and biomarkers might aid diagnosis and severity stratification in the outpatient setting. Antibiotic resistance is a growing problem that reinforces the importance of novel antibiotics. And finally, prevention and the use of anti-pneumococcal vaccine are instrumental in reducing the burden of disease.

SUMMARY

Most of CAP cases are managed in the community; however, most research comes from hospitalized severe patients. New and awaited advances might contribute to aid diagnosis, cause and assessment of patients with CAP in the community. This knowledge might prove decisive in the execution of stewardship programmes that maintain current antibiotics, safeguard future ones and reinforce prevention.

Circulating sphingosine-1-phosphate as a prognostic biomarker for community-acquired pneumonia

Early determination of the severity of Community-Acquired Pneumonia (CAP) is essential for better disease prognosis. Current predictors are suboptimal, and their clinical utility remains to be defined, highlighting the need for developing biomarkers with efficacious prognostic value. Sphingosine-1-phosphate (S1P) is a bioactive sphingolipid with a documented regulatory role in immune defense and maintenance of endothelial barrier integrity. For early diagnose of CAP and recognition of severe CAP patients, we conduct this pilot study to access the potential utility of the circulating S1P in an Emergency department setting. In the prospective study, plasma S1P levels were quantified in healthy controls and patients with CAP. Also, their discriminating power was assessed by receiver operating characteristic analysis. The association between S1P levels and disease severity indices was assessed by Spearman correlation and logistic regression tests. Patients with CAP had significantly higher plasma S1P levels than healthy individuals (CAP: 27.54 ng/ml, IQR = 14.37-49.99 ng/ml; Controls: 10.58 ng/ml, IQR = 4.781-18.91 ng/ml; p < 0.0001). S1P levels were inversely correlated with disease severity in patients with CAP. Based on multivariate logistic regression analysis, the plasma S1P concentrations showed significant predicting power for mortality (OR: 0.909; CI: 0.801-0.985; p < 0.05), intensive care unit admission (OR: 0.89; CI: 0.812-0.953; p < 0.005) and long hospital stay (OR: 0.978; CI: 0.961-0.992; p < 0.005). Interestingly, significantly elevated levels of S1P were noted in patients who received methylprednisolone treatment during hospitalization. These results suggest that S1P may be associated with the pathogenesis of CAP and may have prognostic utility in CAP and its therapy, especially in the Emergency Department setting.

Efficacy and safety of antimicrobial de-escalation as a clinical strategy

INTRODUCTION

De-escalation is a widely recommended strategy in regard to guidelines, with an associated adherence to guidelines being around 50%. This review discusses data supporting de-escalation and possible obstacles for its implementation. Areas covered: Although it does not have a consensual definition, de-escalation consists of reducing the spectrum of empirical antimicrobial treatment based on the microbiological findings. Many observational studies have suggested that this strategy is likely safe and efficient for treating various types of infection. However, randomized controlled trials published as of now have not shown any improvement on the outcomes. Regarding the adverse effects of de-escalation on ecological pressure and multidrug resistance emergence, the data are contradictory. The implementation of new techniques, such as rapid diagnosis, can help guide clinicians. Expert opinion: De-escalation should be included as part of a large antibiotic stewardship program to balance the risk and benefit of each administration, and each physician prescribing antibiotics should be challenged for the quality of her/his prescription on a daily basis. In the future, one of our duties will involve determining whether a delay of antimicrobial treatment - making it possible to improve diagnostic performance and obtain the first laboratory results - is either safe or unsafe for our patients.

The moderate predictive value of serial serum CRP and PCT levels for the prognosis of hospitalized community-acquired pneumonia

BACKGROUND

To predict the prognosis by observing the dynamic change of C-reactive protein (CRP) and procalcitonin (PCT) for hospitalized community-acquired pneumonia (CAP).

METHODS

The data were collected from January to December 2017 from the first affiliated Hospital of Zhengzhou University. Demographic and clinical patient information including age, length of hospital stay and Charlson Comorbidity Index (CCI) were recorded. Blood samples were taken for CRP, PCT, and white blood cell count (WBC). Receiver Operating Characteristic (ROC) curve was used to verify each biomarker's association with the prognosis of pneumonia.

RESULTS

A total of 350 patients were enrolled in the study. The 30-day mortality was 10.86%. Serial serum CRP3, CRP5, PCT3, PCT5 and PCT5c levels were statistically lower in CAP survivors than non-survivors. CRP3c < 0, CRP5c < 0 and PCT5c < 0 were observed with a statistically lower frequency in patients with 30-day mortality and initial treatment failure. The AUC for 30-day mortality for serial CRP levels combined with CRP clearances was 0.85 (95% CI 0.77-0.92), as compared to an AUC of 0.81 (95% CI 0.73-0.9) for serial PCT levels combined with PCT clearances.

CONCLUSIONS

Serum serial CRP and PCT levels had moderate predictive value for hospitalized CAP prognosis. The dynamic CRP and PCT changes may potentially be used in the future to predict hospitalized CAP prognosis.

Footprints of Sepsis Framed Within Community Acquired Pneumonia in the Blood Transcriptome

We analyzed the blood transcriptome of sepsis framed within community-acquired pneumonia (CAP) and characterized its molecular and cellular heterogeneity in terms of functional modules of co-regulated genes with impact for the underlying pathophysiological mechanisms. Our results showed that CAP severity is associated with immune suppression owing to T-cell exhaustion and HLA and chemokine receptor deactivation, endotoxin tolerance, macrophage polarization, and metabolic conversion from oxidative phosphorylation to glycolysis. We also found footprints of host's response to viruses and bacteria, altered levels of mRNA from erythrocytes and platelets indicating coagulopathy that parallel severity of sepsis and survival. Finally, our data demonstrated chromatin re-modeling associated with extensive transcriptional deregulation of chromatin modifying enzymes, which suggests the extensive changes of DNA methylation with potential impact for marker selection and functional characterization. Based on the molecular footprints identified, we propose a novel stratification of CAP cases into six groups differing in the transcriptomic scores of CAP severity, interferon response, and erythrocyte mRNA expression with impact for prognosis. Our analysis increases the resolution of transcriptomic footprints of CAP and reveals opportunities for selecting sets of transcriptomic markers with impact for translation of omics research in terms of patient stratification schemes and sets of signature genes.

Risk stratification and prediction value of procalcitonin and clinical severity scores for community-acquired pneumonia in ED

OBJECTIVE

Community-acquired pneumonia (CAP) is a common presentation to the emergency department (ED) and has high mortality rates. The aim of our study is to investigate the risk stratification and prognostic prediction value of precalcitonin (PCT) and clinical severity scores on patients with CAP in ED.

METHODS

226 consecutive adult patients with CAP admitted in ED of a tertiary teaching hospital were enrolled. Demographic information and clinical parameters including PCT levels were analyzed. CURB65, PSI, SOFA and qSOFA scores were calculated and compared between the severe CAP (SCAP) and non-severe CAP (NSCAP) group or the death and survival group. Receiver-operating characteristic (ROC) curves for 28-day mortality were calculated for each predictor using cut-off values. Logistic regression models and area under the curve (AUC) analysis were performed to compare the performance of predictors.

RESULTS

Fifty-one patients were classified as SCAP and forty-nine patients died within 28days. There was significant difference between either SCAP and NSCAP group or death and survival group in PCT level and CURB65, PSI, SOFA, qSOFA scores (p < 0.001). The AUCs of the PCT and CURB65, PSI, SOFA and qSOFA in predicting SCAP were 0.875, 0.805, 0.810, 0.852 and 0.724, respectively. PCT is superior in predicting SCAP and the models combining PCT and SOFA demonstrated superior performance to those of PCT or the CAP severity score alone. The AUCs of the PCT and CURB65, PSI, SOFA and qSOFA in predicting 28-day mortality were 0.822, 0.829, 0.813, 0.913 and 0.717, respectively. SOFA achieved the highest AUC and the combination of PCT and SOFA had the highest superiority over other combinations in predicting 28-day mortality.

CONCLUSION

Serum PCT is a valuable single predictor for SCAP. SOFA is superior in prediction of 28-day mortality. Combination of PCT and SOFA could improve the performance of single predictors. More further studies with larger sample size are warranted to validate our results.

Determining best outcomes from community-acquired pneumonia and how to achieve them

Community-acquired pneumonia (CAP) is a common acute medical illness with a standard, effective treatment that was introduced before the evidenced-based medicine era. Mortality rates have improved in recent decades but improvements have been minimal when compared to other conditions such as acute coronary syndromes. The standardized approach to treatment makes CAP a target for comparative performance and outcome measures. While easy to collect, simplistic outcomes such as mortality, readmission and length of stay are difficult to interpret as they can be affected by subjective choices and health care resources. Proposed clinical- and patient-reported outcomes are discussed below and include measures such as the time to clinical stability (TTCS) and patient satisfaction, which can be compared between health institutions. Strategies to improve these outcomes include use of a risk stratification tool, local antimicrobial guidelines with antibiotic stewardship and care bundles to include early administration of antibiotics and early mobilization.