Defining severe community-acquired pneumonia

Diagnostic and prognostic value of deregulated long non-coding RNA RPPH1 in patients with severe community-acquired pneumonia: a retrospective cohort study

BACKGROUND

Severe community-acquired pneumonia (SCAP) is one of the most common critical and acute diseases in the respiratory and acute medicine department. The expression and significance of lncRNA RPPH1 (RPPH1) in SCAP were assessed aiming to explore a biomarker assisting in the screening and management of SCAP.

METHODS

This study is a retrospective study enrolled 97 SCAP patients, 102 mild community-acquired pneumonia (MCAP) patients, and 65 healthy individuals. The serum expression of RPPH1 of study subjects was evaluated using PCR. The diagnostic and prognostic significance of RPPH1 in SCAP was evaluated by ROC and Cox analyses. Meanwhile, the correlation of RPPH1 with patients' clinicopathological features was evaluated by spearman correlation analysis to evaluate its role in assessing disease severity.

RESULTS

A significant downregulation of RPPH1 was observed in the serum of SCAP patients compared with MCAP and healthy individuals. RPPH1 was positively correlated with ALB (r = 0.74) and negatively correlated with C-reactive protein (r = -0.69), neutrophil-to-lymphocyte ratio (r = -0.88), procalcitonin (r = -0.74), and neutrophil (r = -0.84) of SCAP patients, which are associated with the development and severity of SCAP. Additionally, reduced RPPH1 was closely associated with the 28-day development-free survival of SCAP patients and served as an adverse prognostic indicator together with procalcitonin.

CONCLUSIONS

Downregulated RPPH1 in SCAP could act as a diagnostic biomarker screening SCAP from healthy and MCAP individuals and act as a prognostic biomarker predicting patients' disease conditions and outcomes. The demonstrated significance of RPPH1 in SCAP could assist the clinical antibiotic therapies of SCAP patients.

Evaluation of severity scoring systems in patients with severe community acquired pneumonia

BACKGROUND

The aim of this study was to evaluate the ability of severity scoring systems to predict 30-day mortality in patients with severe community-acquired pneumonia.

METHODS

The study included 98 patients aged ≥18 years with community acquired pneumonia hospitalized at the Intensive Care Unit of the University Clinic for Infectious Diseases in Skopje, Republic of North Macedonia, during a 3-year period. We recorded demographic, clinical and common biochemical parameters. Five severity scores were calculated at admission: CURB 65 (Confusion, Urea, Respiratory Rate, Blood pressure, Age ≥65 years), SCAP (Severe Community Acquired Pneumonia score), SAPS II (Simplified Acute Physiology Score), SOFA (Sequential Organ Failure Assessment Score) and MPM (Mortality Prediction Model). Primary outcome variable was 30-day in-hospital mortality.

RESULTS

The mean age of the patients was 59.08 ± 15.76 years, predominantly males (68%). The overall 30-day mortality was 52%. Charlson Comorbidity index was increased in non-survivors (3.72 ± 2.33) and was associated with the outcome. All severity indexes had higher values in patients who died, that showed statistical significance between the analysed groups. The areas under curve (AUC) values of the five scores for 30-day mortality were 0.670, 0.732, 0,726, 0.785 and 0.777, respectively.

CONCLUSION

Widely used severity scores accurately detected patients with pneumonia that had increased risk for poor outcome, but none of them individually demonstrated any advantage over the others.

Demographics, guidelines, and clinical experience in severe community-acquired pneumonia

Mortality in patients with community-acquired pneumonia (CAP) who require intubation or support with inotropes in an intensive care unit setting remains extremely high (up to 50%). Systematic use of objective severity-of-illness criteria, such as the Pneumonia Severity Index (PSI), British Thoracic Society CURB-65 (an acronym meaning Confusion, Urea, Respiratory rate, Blood pressure, age ≥65 years), or criteria developed by the Infectious Diseases Society of America/American Thoracic Society, to aid site-of-care decisions for pneumonia patients is emerging as a step forward in patient management. Experience with the Predisposition, Infection, Response, and Organ dysfunction (PIRO) score, which incorporates key signs and symptoms of sepsis and important CAP risk factors, may represent an improvement in staging severe CAP. In addition, it has been suggested that implementing a simple care bundle in the emergency department will improve management of CAP, using five evidence-based variables, with immediate pulse oxymetry and oxygen assessment as the cornerstone and initial step of treatment.

Systemic and bronchoalveolar cytokines as predictors of in-hospital mortality in severe community-acquired pneumonia

OBJECTIVES

The aim of this study was to determine whether cytokine expression (interleukin [IL]-1beta, IL-6, IL-8, IL-10, and tumor necrosis factor [TNF]-alpha), C-reactive protein, and endotoxins on the first day of intensive care unit (ICU) admission are associated with hospital mortality in severe community-acquired pneumonia (CAP).

DESIGN

This was a prospective study with bronchoalveolar lavage (BAL) and blood sampling.

SETTING

This study was carried out in a 44-bed medical ICU of a 1700-bed university hospital.

PATIENTS

Participants included 112 mechanically ventilated patients with severe CAP.

INTERVENTIONS

Serum and BAL fluid IL-1beta, IL-6, IL-8, IL-10, TNF-alpha, C-reactive protein, and endotoxins on the first day of ICU admission were obtained.

MEASUREMENTS AND MAIN RESULTS

The concentrations of TNF-alpha in BALF and IL-6, IL-8, IL-10, and TNF-alpha in serum were higher in nonsurvivors than in survivor patients with CAP. Of these 112 patients with severe CAP (39%), 44 developed acute respiratory distress syndrome (ARDS); these patients seemed to have higher serum IL-6, IL-8, and IL-10 levels than did the non-ARDS group. Furthermore, in the ARDS population, we found that the endotoxin levels in the BAL fluid were higher in the survival than in the nonsurvival group and BAL fluid concentrations of IL-6, IL-8, and IL-1beta and sera levels of IL-6 and IL-10 were lower in the survival than in the nonsurvival group, and they were associated with a high negative predictive value.

CONCLUSIONS

Serum and BAL fluid levels of the studied cytokines on admission may provide valuable prognostic information for patients with severe CAP.

Biomarkers of thrombosis, fibrinolysis, and inflammation in patients with severe sepsis due to community-acquired pneumonia with and without Streptococcus pneumoniae

BACKGROUND

Severe Streptococcus pneumoniae (S. pneum) pneumonia has historically been associated with an acute presentation and increased mortality. Using data from patients with community-acquired pneumonia (CAP) and severe sepsis, we investigated: (1) the baseline patient characteristics and biomarkers of thrombosis, fibrinolysis, and inflammation in patients with CAP due to S. pneum infection (S. pneum CAP) or CAP due to infection with other or unidentified organisms (non-S. pneum CAP); (2) the behavior of these biomarkers over time and during treatment with drotrecogin alfa (activated) (DrotAA, recombinant activated protein C).

PATIENTS AND METHODS

Data from the PROWESS (Recombinant Human Activated Protein C Worldwide Evaluation on Severe Sepsis) trial were retrospectively analyzed by treatment (DrotAA or placebo) in patients with CAP.

RESULTS

Patients with S. pneum CAP (n = 157) tended to be younger and had fewer comorbid conditions than patients with non-S. pneum CAP (n = 445). Overall disease severity (median APACHE II scores) was not significantly different between the two groups at baseline. However, there were significant baseline differences in protein C and markers of coagulation, fibrinolysis, and inflammation. Although thrombosis markers were not different at baseline, D-dimer levels significantly increased from baseline to day 4 in placebo-treated patients with S. pneum compared to those with non-S. pneum. DrotAA treatment was associated with statistically significant improvements in protein C and markers of thrombosis in patients with S. pneum. In addition, the proportion of patients with severe protein C deficiency ( </= 40% activity) at baseline was significantly greater in patients with S. pneum than those with non-S. pneum. Among patients with S. pneum and severe protein C deficiency at baseline, a significantly greater proportion of patients were no longer severely protein C deficient after 4 days of DrotAA therapy.

CONCLUSION

In this population of patients with severe sepsis, patients with S. pneum CAP had a more severe dysregulation of coagulation, fibrinolysis, and inflammation than patients with non-S. pneum CAP; the former also developed significantly elevated levels of markers of thrombosis. Treatment with DrotAA was associated with significant improvements in protein C levels as well as markers of thrombosis. These characteristics may make patients with S. pneum CAP and severe sepsis particularly suited to derive a benefit from therapy with DrotAA.

Community-Acquired Pneumonia—Back to Basics

Lower respiratory tract infections are among the most common infectious diseases worldwide and are caused by the inflammation and consolidation of lung tissue due to an infectious agent.¹ The clinical criteria for the diagnosis include chest pain, cough, auscultatory findings such as rales or evidence of pulmonary consolidation, fever, or leukocytosis.

Severe community-acquired pneumonia: approach to therapy

Despite substantial progress in therapeutic options, severe community-acquired pneumonia (CAP) remains a significant cause of morbidity and mortality worldwide. Recognising the clinical importance of CAP over the past several years, different medical societies and health organisations in different countries have proposed specific guidelines for the management of CAP. Early and rapid initiation of antimicrobial therapy has been advocated for a favourable outcome. Treatment is empirical as the diagnostic yield for potential pathogens does not exceed 50%. Dual therapy is emerging as the preferred therapy for severe CAP. The regimen is based on an epidemiological approach with emphasis on covering both typical and atypical pathogens. Non-antimicrobial adjuvant therapies including non-invasive ventilation and immunomodulatory agents are emerging as promising area for future development.

Early evolution of arterial oxygenation in severe community-acquired pneumonia: a prospective observational study

PURPOSE

Acute respiratory failure requiring mechanical ventilation in severe community-acquired pneumonia has been shown to be a significant negative prognostic factor. We analyzed the early evolution of the Pao(2)/Fio(2) ratio and evaluated its clinical value as an outcome predictor.

MATERIALS AND METHODS

This is a prospective study conducted in a tertiary referral hospital. In 62 adult patients requiring early mechanical ventilation due to severe community-acquired pneumonia, we measured serial changes in Pao(2)/Fio(2) ratio and other clinical variables within the first 48 hours of mechanical ventilation and compared the difference between survivors and nonsurvivors.

RESULTS

The initial Pao(2)/Fio(2) ratio was lower in nonsurvivors (n = 27) than in survivors (n = 35) (158.0 +/- 55.8 vs 117.9 +/- 50.6, P = .025). Over the next 48 hours, the ratio increased significantly in survivors but not in nonsurvivors (analysis of variance, P < .001). An increase in Pao(2)/Fio(2) ratio greater than 56 mm Hg had a sensitivity of 75% and a specificity of 81% of survival. A definite causative pathogen was identified in 36 patients (58%) and the 3 most commonly isolated pathogens were Streptococcus pneumoniae, Staphylococcus aureus, and Klebsiella pneumoniae. Ten patients received inadequate initial empirical antimicrobial therapy, in which the Pao(2)/Fio(2) ratio change was significantly less than those who were adequately treated (analysis of variance, P < .001). Mortality was much higher (86% [6/7]) in patients who received inadequate antibiotics and where Pao(2)/Fio(2) ratio change was less than 56 mm Hg. On multivariate analysis, trend changes in Pao(2)/Fio(2) ratio over 48 hours, shock, and Acute Physiology and Chronic Health Evaluation II score were documented to be independent predictors of mortality.

CONCLUSIONS

A progressive improvement of Pao(2)/Fio(2) ratio during the first 48 hours of mechanical ventilation indicates favorable outcome. Serial measurement of this ratio should be considered in decision making for therapeutic strategy.

Polmoniti

Non è semplice ordinare una materia così articolata come la patologia infettiva respiratoria. La gestione delle polmoniti si presenta complessa per le problematiche ad esse connesse (aspetti epidemiologici, microbiologici, farmacoeconomici, ecc.) per cui è necessario confrontare costantemente le conoscenze di quanti hanno dimestichezza in questo settore per proporre e condividere linee strategiche che tengano in considerazione da un lato i suggerimenti contenuti nelle linee guida più accreditate e dall’altro le esperienze prodotte dalla pratica quotidiana al fine di migliorare potenzialità e metodi di cura e razionalizzare i percorsi diagnostico-terapeutici più idonei a fronteggiarle. L’incremento costante delle infezioni respiratorie sostenute dai patogeni emergenti e interessate dal fenomeno delle resistenze batteriche è oggi un elemento preoccupante che rischia, tra l’altro, di vanificare, in carenza di un adeguamento costante, tutti gli schemi, le linee guida e i protocolli diagnostico-terapeutici elaborati in questi ultimi anni per un razionale trattamento delle patologie pneumoinfettivologiche. Il trattamento delle polmoniti acquisite in comunità (CAP) rappresenta uno degli argomenti più dibattuti in pneumologia negli ultimi anni, sottoposto a continue revisioni, aggiornamenti, precisazioni dottrinarie.

Severe community-acquired pneumonia as a cause of severe sepsis: data from the PROWESS study

OBJECTIVE

To investigate community-acquired pneumonia (CAP) as a cause of severe sepsis in the PROWESS (Recombinant Human Activated Protein C Worldwide Evaluation in Severe Sepsis) trial and to evaluate the effect of drotrecogin alfa (activated) (DrotAA) in this subgroup.

DESIGN

Retrospective analysis of the severe CAP subgroup in the PROWESS trial.

SETTING

Tertiary care institutions in 11 countries.

INTERVENTIONS

DrotAA (n = 850), 24 microg.kg.hr for 96 hrs, or placebo (n = 840).

PARTICIPANTS

The 1,690 patients with severe sepsis enrolled in the PROWESS trial.

MEASUREMENTS AND MAIN RESULTS

Patients were classified as having CAP if lung was the primary site of infection and if they were enrolled directly from home (private residence) with </=4 days in the hospital before receipt of study drug in the PROWESS trial. Survival at 28 days, hospital discharge, and 90 days was compared in DrotAA and placebo groups in the CAP subgroup of PROWESS and CAP subgroups based on disease severity. Of the 1,690 PROWESS patients, 35.6% (DrotAA, n = 324; placebo, n = 278) were classified as severe CAP. Of these severe CAP patients, 26.1% had Streptococcus pneumoniae infections. Within CAP, 79.1% were enrolled by the end of the second calendar day in the hospital, and approximately 90% of CAP patients were at high risk of death according to the Pneumonia Severity Index category. Based on their dependence on vasopressors, 59% of CAP patients were judged at high risk of death. Biomarkers of coagulation and inflammation were markedly abnormal in severe CAP patients. In severe CAP patients treated with DrotAA, a relative risk reduction in mortality of 28% was observed at 28 days, with a relative risk reduction in mortality of 14% observed at 90 days from the start of study drug infusion. The survival benefit was most pronounced in severe CAP patients with S. pneumoniae and in severe CAP patients at high risk of death as indicated by Acute Physiology and Chronic Health Evaluation II score of >/=25, Pneumonia Severity Index score of >/=4, or CURB-65 (confusion, urea, respiratory rate, blood pressure, age) score of >/=3.

CONCLUSIONS

CAP associated with a high Pneumonia Severity Index score, bacteremia, or an intense coagulation and inflammatory response requiring intensive care unit care were indicators of a high risk of death from severe sepsis. In patients with severe sepsis resulting from CAP, a readily identifiable disease, DrotAA, improved survival compared with placebo.

Severe community-acquired pneumonia: what's in a name?

PURPOSE OF REVIEW

Formerly, patients with community-acquired pneumonia admitted to an intensive care unit were considered as having the severe form of the disease. Recently, guidelines have distinguished severe and non-severe community-acquired pneumonia based on clinical definitions. In this review, we describe the different definitions of severe community-acquired pneumonia, and whether a differentiation based on these definitions reflects variation in etiology, risk factors, diagnostic approaches and treatment.

RECENT FINDINGS

New definitions do not seem to accurately identify patients with high risks of mortality; patients not admitted to an intensive care unit could also be diagnosed as having severe community-acquired pneumonia. Host-factors, such as genetic factors and underlying diseases, can influence severity of presentation of community-acquired pneumonia. Distribution of pathogens in severe and non-severe disease forms is comparable. Initial antibiotic therapy in patients with severe disease should provide coverage of Streptococcus pneumoniae and Legionella pneumophila, as delay is associated with worse outcomes. However, recent studies also suggested an additional benefit of atypical coverage in non-severe disease. As a result, initial therapy with a beta-lactam plus a macrolide or an anti-pneumococcal fluoroquinolone is recommended for all patients with community-acquired pneumonia. Furthermore, the value of vaccination against pneumococci to prevent episodes of severe disease is yet unknown.

SUMMARY

As current guidelines do not adequately identify patients with high risk of mortality and intensive care unit admittance, clinical judgment remains important. Based on distribution of pathogens, investigational procedures and therapy recommended in recent guidelines, differentiation between severe and non-severe community-acquired pneumonia does not seem useful. Whether atypical coverage indeed has additional value in non-severe or pneumococcal CAP, however, remains to be determined. In addition, the preventive benefit of influenza and pneumococcal vaccination for development of SCAP awaits further evidence.

How should we make the admission decision in community-acquired pneumonia?

The spectrum of pneumonia patients ranges from only slightly compromised patients to patients who require life-sustaining measures. Admission decision support algorithms usually are not required for patients at either end of the spectrum. For patients presenting with intermediate severity of illness, decision support algorithms have shown that they can support clinicians in the admission decision and complement the clinicians' experience and clinical judgment with an objective tool. Clinical information systems may help overcome the existing obstacles to successful implementation. Successful guideline implementation in a clinical setting includes strategies that target not only the disease, but also include other forces that significantly influence the admission decision. Shared decision making and better managing of patients' expectations about treatment and prognosis need to be incorporated in the overall admission decision. The availability of improved outpatient management, such as outpatient intravenous antibiotic treatment and home health care, and a change in physicians' perspectives and patients' expectations may help to increase the proportion of outpatient management without compromising the quality of care. Decision support tools for pneumonia are available and show promising results. Further studies are needed, however, that show the successful dissemination and clinical implementation during routine patient care. Studies are needed that assess the impact of guidelines and prediction rules on patient outcomes. As the example of the PSI shows, the development, implementation, and dissemination of admission decision support systems is not a revolutionary, but a stepwise, evolutionary process that requires many years of research.