Pulmonary complications of pneumococcal community-acquired pneumonia: incidence, predictors, and outcomes

Complicated pneumococcal pneumonia in the era of higher-valent pneumococcal conjugate vaccines: a systematic literature review and meta-analysis, 2001-2022

PURPOSE

To estimate pneumococcal conjugate vaccine (PCV) national program impact on pneumococcal complicated pneumonia (PnCP) based on changes in PnCP population-based incidence, PnCP proportion of all-cause complicated pneumonia (or invasive pneumococcal disease), and PnCP serotype distribution.

METHODS

MEDLINE, EMBASE, and Global Index Medicus articles (2001-March 2022) reporting laboratory-confirmed PnCP studies were stratified by age group, outcome measure, PCV program period(s) (pre-PCV, transition, and post-PCV), serotype distribution (based on serotyping methodology used), and PCV serotype formulation. Random effect meta-analysis of the total number of serotyped isolates within each study was used to calculate pooled serotype-specific percentages.

RESULTS

Of 1360 publications screened, the 134 studies included from 30 countries differed widely by methodological approaches. Pediatric PnCP incidence tended to decline from pre-PCV to post-PCV periods, as did PnCP as a proportion of all-cause complicated pneumonia from transition to post-PCV periods. Studies describing changes in serotype distribution by PCV program period applied detection methods that varied from pre-PCV period microbiological culture with Quellung serotyping to in the transition and post-PCV periods molecular methods like PCR. Meta-analysis revealed near elimination of pediatric PCV7-serotype PnCP between pre- and post-PCV, while the PCV13nonPCV7 percentage increased from 51.1% pre-PCV period to 76.5% in the transition period, remaining stable post-PCV period. Non-PCV13 serotypes increased slightly from low baseline numbers. Adult data were lacking or inconsistent.

CONCLUSIONS

Although studies were heterogeneous, pediatric PnCP incidence and proportion tended to decline from pre-PCV to post-PCV periods, and PCV13nonPCV7 serotype distribution percentage remained unchanged from transition to post-PCV period. Standardization of PnCP surveillance methods, definitions, and reporting is needed to evaluate accurately PCV program impact.

Willingness to engage in self-care impacts clinical outcomes at discharge in hospitalized pneumonia patients: a descriptive study

BACKGROUND

The objective of this study was to evaluate the association between willingness to engage in self-care and clinical outcomes in patients hospitalized with community-acquired pneumonia (CAP).

METHODS

An observational study in patients hospitalized with CAP was conducted. Patients were divided into two groups according to the willingness to engage in self-care, that was assessed with the Patient Activation Measure (PAM). Participants with scores ≤ 47.0 points were included in the unwillingness to engage in self-care group, and patients with PAM score > 47 points were included in the willingness to engage in self-care group. Main variables were assessed at hospital discharge and included clinical symptoms (cough, dyspnea, pain and fatigue), physical status, activity levels, psychological inflexibility and restrictions in daily life activities and social participation.

RESULTS

A total of 66 patients were included in the study (34 in the patients unwilling to engage and 32 in the patients willing to engage). Significant differences were found in clinical symptoms, psychological inflexibility, and restrictions in daily life activities and social participation in favor to patients' willingness to engage in self-care at hospital discharge.

CONCLUSIONS

Patients with CAP willing to engage in self-care showed improvements in clinical symptoms, psychological flexibility, and fewer limitations in daily activities and social participation at discharge.

Systematic review on serotypes distribution of pneumococcal pneumonia in adults and the elderly

BACKGROUND

Pneumococcal pneumonia is a major cause of morbidity and mortality among adults, especially those over 65 years of age. Understanding pneumococcal serotype-specific epidemiology in adults and elderly is necessary to inform vaccination policies and to guide the inclusion of serotypes in pneumococcal vaccines. This study aimed to identify the serotypes causing pneumonia in the elderly.

METHODS

A systematic review search was performed using the PubMed database from 1984 to 2020. The search was limited to articles written in English. Studies assessing pneumococcal pneumonia in adults were included. Meta-analysis, other systematic literature reviews and case-reports were excluded. Studies published after the introduction of vaccines (PPSV23 and PCVs) were included.

RESULTS

Forty studies were included. The most common serotype identified in the majority of the articles in adults was the serotype 3 followed by serotypes 19A and 11A. Those serotypes are included in current vaccines. Emergence of non-vaccine serotypes was also observed.

CONCLUSION

Pneumococcal pneumonia remains a high burden in the elderly despite the existence of vaccines for many years. In 2019, nearly 1.4 million deaths were attributable to pneumococcal pneumonia (50% of whom were over 70 years old) and was the leading cause of deaths from infectious disease worldwide. The study highlights the importance of constant monitoring serotypes emerging in this population to better target vaccination strategies.

Factors Associated with Complicated Parapneumonic Pleural Effusion/Empyema in Patients with Community-Acquired Pneumonia: The EMPIR Study

Objectives: To identify factors associated with complicated parapneumonic pleural effusion/empyema (CPPE/empyema) in inpatients with community-acquired pneumonia (CAP) and to build a mathematical model for CPPE/empyema. Methods: This is an observational case-control study nested within a retrospective cohort, based on clinical practice, and including adults hospitalized with CAP from 2009 to 2019. Cases and controls were defined according to diagnosis of CPPE/empyema during admission. For each case, two controls were randomly selected and matched for the period of admission to avoid seasonality bias. Explanatory variables included demographic, analytical, clinical, and radiological data; treatment with corticosteroids on admission; prognostic and CAP severity scales; comorbidity; and the interval between symptoms onset and admission. Results: Of 4372 pneumonias reviewed, 2015 were excluded due to pleural effusion, blunting of the costophrenic angle without thoracentesis, or heart failure. Of the remaining 2357 patients, 106 developed CPPE/empyema (cases), and 212 were selected as controls. Factors associated with CPPE/empyema were pleuritic pain (odds ratio [OR] 7.42, 95% confidence interval [CI] 3.83-14.38), multilobar radiological involvement (OR 4.48, 95% CI 2.26-8.88), and leukocytosis (OR 4.12, 95% CI 1.94-8.76). Corticosteroids showed a protective effect (OR 0.24, 95% CI 0.09-0.61). Age (OR 0.99, 95% CI 0.97-1.02; p = 0.56) and sex (OR 1.91, 95% CI 0.94-3.88; p = 0.074) were adjustment variables. The area under the receiver operating characteristic curve was 0.847 (95% CI 0.772-0.921). Conclusions: Pleuritic pain, multilobar radiological involvement, and leukocytosis are associated with CPPE/empyema in inpatients with CAP. Treatment with corticosteroids upon admission seems to be a protective factor. The discriminative capacity of the resulting multivariable model presents moderate/high accuracy.

Advantages of short-term antimicrobial treatment for pneumonia and aspiration pneumonia in older patients aged over 65: A nationwide inpatient database study

The duration of antimicrobial therapy required to treat community-acquired pneumonia is often longer than expected, likely because of the high number of such inpatients in developed countries with aging populations. In this study, we evaluated the effects of short-term treatments for both pneumonia and aspiration pneumonia in older Japanese adults using the nation's inpatient database. Inpatients aged ≥ 65 years who were admitted to the hospital for pneumonia or aspiration pneumonia between April 1, 2018, and October 31, 2018, were included. We compared patients treated via intravenous antibiotics for 3-7 days to control patients treated with a similar regimen for 8-28 days, using inverse probability of treatment-weighted Cox regression. The primary outcome was relapse or readmission for pneumonia and death within 30 days after completing antimicrobial therapy. The secondary outcomes were average treatment effect for Clostridioides difficile infection (CDI), chest drainage, and length of hospital stay. The total number of eligible patients was 72,294. The hazard ratio for the primary outcome was 1.04 (95% confidence interval: 0.99-1.10). The mean length of hospital stay was shortened to 9.74 days (range, 9.34-10.1) in the short-term treatment group. The prevalence rates of CDI and chest drainage did not differ significantly between the short- and long-term treatment groups. We observed no statistically significant difference in clinical outcomes between the older adults with pneumonia including aspiration pneumonia who received short- vs long-term antimicrobial therapy.

Diagnostic Utility of Pleural C-Reactive Protein and Procalcitonin for Parapneumonic Pleural Effusion: A Head-to-Head Comparison Study

Introduction

The diagnostic utility of pleural fluid C-reactive protein (CRP) and procalcitonin (PCT) for parapneumonic pleural effusion (PPE) is a subject of ongoing investigation. There remains lack studies comparing their diagnostic accuracy in a head-to-head manner. Furthermore, the incremental diagnostic value of their combination over a single marker and the net benefit of them remains unknown.

Methods

This prospective study enrolled participants presenting with undiagnosed pleural effusion, subsequently measuring their pleural levels of CRP and PCT. A diagnostic model that integrated both biomarkers was constructed using logistic regression analysis. The diagnostic performance and net benefit of CRP, PCT, and the composite model were assessed through receiver-operating characteristic (ROC) curve analysis and decision curve analysis (DCA).

Results

The study included 32 PPE patients and 121 patients without PPE. The area under the ROC curve (AUC) for CRP was 0.73 (95% confidence interval [CI]: 0.63-0.83), with a sensitivity of 0.71 (95% CI: 0.55-0.87) and a specificity of 0.68 (95% CI: 0.59-0.77) at a threshold of 10 mg/L. In contrast, the AUC for PCT was 0.58 (95% CI: 0.46-0.69), with sensitivity and specificity rates of 0.50 (95% CI: 0.33-0.67) and 0.65 (95% CI: 0.56-0.74) at a threshold of 0.1 ng/mL, respectively. Notably, the AUC for the diagnostic model was comparable to that of CRP alone at 0.73 (95% CI: 0.63-0.82). DCA showed that applying CRP provided a net clinical benefit, while PCT did not.

Conclusion

Pleural fluid CRP possesses moderate diagnostic capability for PPE, while PCT exhibits limited diagnostic utility. Additionally, the combined application of CRP and PCT does not confer any significant enhancement in diagnostic accuracy over the use of CRP alone.

Retrospective study on the health and economic burden of hospitalized patients due to pneumonia and invasive pneumococcal infections in Belgium settings

INTRODUCTION

pneumococcal infections are associated with high morbidity, hospitalisation and mortality. The objective of this study was to investigate the health and economic burden of all-cause pneumonia and invasive pneumococcal disease in Belgian hospital settings, by patient's age and risk profile.

METHODS

This descriptive retrospective study was conducted in 17 Belgian hospitals. Univariate and multivariate logistic linear regression models were performed. The Health Insurance and patient's cost perspectives were considered because a few studies report these costs.

RESULTS

The analysis has included 4,712 hospital admissions over the year 2018. Median hospitalization costs were higher for invasive pneumococcal infection diagnosis than for all-cause pneumonia (p < 0,001), respectively 4,051€ and 3,362€. Other factors associated with higher hospitalization cost were patient's high-risk profile, admission to emergency unit, transfer from nursing home, admission to intensive care unit and length of stay.

CONCLUSION

Streptococcus pneumoniae infections remain a public health problem with significant cost for the Health Insurance and poor prognosis. Invasive pneumococcal infections are associated with longer hospital stays and required more intensive care than all other causes of pneumonia, in addition to be more costly, which justifies more attention for vaccination. This study also suggests an increase of economic and health burden with age and presence of underlying conditions.

Diabetes Mellitus and Pneumococcal Pneumonia

Currently, there are more than 500 million people suffering from diabetes around the world. People aged 65 years or older are the most affected by this disease, and it is estimated that approximately 96% of diabetes cases worldwide are type 2 diabetes. People with diabetes mellitus are at an increased risk of infections such as pneumonia, due to a series of factors that may contribute to immune dysfunction, including hyperglycemia, inhibition of neutrophil chemotaxis, impaired cytokine production, phagocytic cell dysfunction, altered T cell-mediated immune responses and the co-existence of chronic comorbidities. Rates of infection, hospitalization and mortality in diabetic patients are reported to be higher than in the general population. Research into the risk of infectious diseases such as pneumonia in these patients is very important because it will help improve their management and treatment.

Sepsis-Related Lung Injury and the Complication of Extrapulmonary Pneumococcal Pneumonia

Globally, sepsis and pneumonia account for significant mortality and morbidity. A complex interplay of immune-molecular pathways underlies both sepsis and pneumonia, resulting in similar and overlapping disease characteristics. Sepsis could result from unmanaged pneumonia. Similarly, sepsis patients have pneumonia as a common complication in the intensive care unit. A significant percentage of pneumonia is misdiagnosed as septic shock. Therefore, our knowledge of the clinical relationship between pneumonia and sepsis is imperative to the proper management of these syndromes. Regarding pathogenesis and etiology, pneumococcus is one of the leading pathogens implicated in both pneumonia and sepsis syndromes. Growing evidence suggests that pneumococcal pneumonia can potentially disseminate and consequently induce systemic inflammation and severe sepsis. Streptococcus pneumoniae could potentially exploit the function of dendritic cells (DCs) to facilitate bacterial dissemination. This highlights the importance of pathogen-immune cell crosstalk in the pathophysiology of sepsis and pneumonia. The role of DCs in pneumococcal infections and sepsis is not well understood. Therefore, studying the immunologic crosstalk between pneumococcus and host immune mediators is crucial to elucidating the pathophysiology of pneumonia-induced lung injury and sepsis. This knowledge would help mitigate clinical diagnosis and management challenges.

Pneumococcal Serotype Evolution and Burden in European Adults in the Last Decade: A Systematic Review

Pneumococcal disease is a major cause of morbidity/mortality worldwide, and vaccination is an important measure in its prevention. Despite European children being vaccinated with pneumococcal conjugate vaccines (PCVs), pneumococcal infections are still a major cause of morbidity/mortality in adults with risk conditions and their vaccination might be an important prevention strategy. New PCVs have been approved, but information is lacking on their potential impact in European adults. In our review, we searched PubMed, MEDLINE, and Embase for studies on the additional PCV20 serotypes (concerning incidence, prevalence, disease severity, lethality, and antimicrobial resistance) in European adults, between January 2010 and April 2022, having included 118 articles and data from 33 countries. We found that these serotypes have become more prevalent in both invasive and non-invasive pneumococcal disease (IPD and NIPD), representing a significant proportion of cases (serotypes 8, 12F, 22F) and more serious disease and/or lethality (10A, 11A, 15B, 22F), showing antimicrobial resistance (11A, 15B, 33F), and/or affecting more vulnerable individuals such as the elderly, immunocompromised patients, and those with comorbidities (8, 10A, 11A, 15B, 22F). The relevance of pneumococcal adult carriers (11A, 15B, 22F, and 8) was also identified. Altogether, our data showed an increase in the additional PCV20 serotypes' prevalence, accounting for a proportion of approximately 60% of all pneumococcal isolates in IPD in European adults since 2018/2019. Data suggest that adults, as older and/or more vulnerable patients, would benefit from vaccination with higher-coverage PCVs, and that PCV20 may address an unmet medical need.

Parapneumonic effusions related to Streptococcus pneumoniae: serotype and disease severity trends from 2006 to 2018 in Bristol, UK

RATIONALE

Streptococcus pneumoniae epidemiology is changing in response to vaccination and some data suggest that empyema incidence is increasing. However, differences exist between the UK and US studies. We describe trends in the clinical phenotype of adult pneumococcal pleural infection, including simple parapneumonic effusions (SPE) in the pneumococcal conjugate vaccination (PCV) era.

OBJECTIVES

To determine whether there were differences in pneumococcal disease presentation and severity associated with pleural infection.

METHODS

A retrospective cohort study, all adults ≥16 years admitted to three large UK hospitals, 2006-2018 with pneumococcal disease. 2477 invasive pneumococcal cases were identified: 459 SPE and 100 pleural infection cases. Medical records were reviewed for each clinical episode. Serotype data were obtained from the UK Health Security Agency national reference laboratory.

RESULTS

Incidence increased over time, including non-PCV-serotype disease. PCV7-serotype disease declined following paediatric PCV7 introduction, but the effect of PCV13 was less apparent as disease caused by the additional six serotypes plateaued with serotypes 1 and 3 causing such parapneumonic effusions from 2011 onwards.Patients with pleural infection had a median survival 468 days (95% CI 340 to 590) vs 286 days (95% CI 274 to 335) in those with SPE. Pleural infection associated with frank pus had lower 90-day mortality than pleural infection without pus (0% vs 29%, p<0.0001). 90-day mortality could be predicted by baseline increased RAPID (Renal, Age, Purulence, Infection source, and Dietary factors) score (HR 15.01, 95% CI 1.24 to 40.06, p=0.049).

CONCLUSIONS

Pneumococcal infection continues to cause severe disease despite the introduction of PCVs. The predominance of serotype 1 and 3 in this adult UK cohort is in keeping with previous studies in paediatric and non-UK studies. Rising non-PCV serotype disease and limited impact of PCV13 on cases caused by serotypes 1 and 3 offset the reductions in adult pneumococcal parapneumonic effusion disease burden observed following the introduction of the childhood PCV7 programme.

Acute organ injury and long-term sequelae of severe pneumococcal infections

Streptococcus pneumoniae (Spn) is a major public health problem, as it is a main cause of otitis media, community-acquired pneumonia, bacteremia, sepsis, and meningitis. Acute episodes of pneumococcal disease have been demonstrated to cause organ damage with lingering negative consequences. Cytotoxic products released by the bacterium, biomechanical and physiological stress resulting from infection, and the corresponding inflammatory response together contribute to organ damage accrued during infection. The collective result of this damage can be acutely life-threatening, but among survivors, it also contributes to the long-lasting sequelae of pneumococcal disease. These include the development of new morbidities or exacerbation of pre-existing conditions such as COPD, heart disease, and neurological impairments. Currently, pneumonia is ranked as the 9^th leading cause of death, but this estimate only considers short-term mortality and likely underestimates the true long-term impact of disease. Herein, we review the data that indicates damage incurred during acute pneumococcal infection can result in long-term sequelae which reduces quality of life and life expectancy among pneumococcal disease survivors.

Diagnostic value of soluble biomarkers for parapneumonic pleural effusion

Parapneumonic pleural effusion (PPE) is a common complication in patients with pneumonia. Timely and accurate diagnosis of PPE is of great value for its management. Measurement of biomarkers in circulating and pleural fluid have the advantages of easy accessibility, short turn-around time, objectiveness and low cost and thus have utility for PPE diagnosis and stratification. To date, many biomarkers have been reported to be of value for the management of PPE. Here, we review the values of pleural fluid and circulating biomarkers for the diagnosis and stratification PPE. The biomarkers discussed are C-reactive protein, procalcitonin, presepsin, soluble triggering receptor expressed on myeloid cells 1, lipopolysaccharide-binding protein, inflammatory markers, serum amyloid A, soluble urokinase plasminogen activator receptor, matrix metalloproteinases, pentraxin-3 and cell-free DNA. We found that none of the available biomarkers has adequate performance for diagnosing and stratifying PPE. Therefore, further work is needed to identify and validate novel biomarkers, and their combinations, for the management of PPE.

Burden of pneumococcal disease among adults in Southern Europe (Spain, Portugal, Italy, and Greece): a systematic review and meta-analysis

The aim was to summarize pneumococcal disease burden data among adults in Southern Europe and the potential impact of vaccines on epidemiology. Of 4779 identified studies, 272 were selected. Invasive pneumococcal disease (IPD) incidence was 15.08 (95% CI 11.01-20.65) in Spain versus 2.56 (95% CI 1.54-4.24) per 100,000 population in Italy. Pneumococcal pneumonia incidence was 19.59 (95% CI 10.74-35.74) in Spain versus 2.19 (95% CI 1.36-3.54) per 100,000 population in Italy. Analysis of IPD incidence in Spain comparing pre-and post- PCV7 and PCV13 periods unveiled a declining trend in vaccine-type IPD incidence (larger and statistically significant for the elderly), suggesting indirect effects of childhood vaccination programme. Data from Portugal, Greece and, to a lesser extent, Italy were sparse, thus improved surveillance is needed. Pneumococcal vaccination uptake, particularly among the elderly and adults with chronic and immunosuppressing conditions, should be improved, including shift to a higher-valency pneumococcal conjugate vaccine when available.

Understanding the Host in the Management of Pneumonia. An Official American Thoracic Society Workshop Report

Pneumonia causes a significant burden of disease worldwide. Although all populations are at risk of pneumonia, those at extremes of age and those with immunosuppressive disorders, underlying respiratory disease, and critical illness are particularly vulnerable. Although clinical practice guidelines addressing the management and treatment of pneumonia exist, few of the supporting studies focus on the crucial contributions of the host in pneumonia pathogenesis and recovery. Such essential considerations include the host risk factors that lead to susceptibility to lung infections; biomarkers reflecting the host response and the means to pursue host-directed pneumonia therapy; systemic effects of pneumonia on the host; and long-term health outcomes after pneumonia. To address these gaps, the Pneumonia Working Group of the Assembly on Pulmonary Infection and Tuberculosis led a workshop held at the American Thoracic Society meeting in May 2018 with overarching objectives to foster attention, stimulate research, and promote funding for short-term and long-term investigations into the host contributions to pneumonia. The workshop involved participants from various disciplines with expertise in lung infection, pneumonia, sepsis, immunocompromised patients, translational biology, data science, genomics, systems biology, and clinical trials. This workshop report summarizes the presentations and discussions and important recommendations for future clinical pneumonia studies. These recommendations include establishing consensus disease and outcome definitions, improved phenotyping, development of clinical study networks, standardized data and biospecimen collection and protocols, and development of innovative trial designs.

C-Reactive Protein to rule out complicated pneumococcal disease manifestations; a retrospective cohort study in adults with pneumococcal bacteraemia

OBJECTIVES

To explore the negative predictive value (NPV) of CRP at admission to exclude complicated disease manifestations.

METHODS

A Dutch multicentre retrospective cohort study was conducted between 01-01-2012 and 30-06-2020. Adults with positive blood cultures for S. pneumoniae, whose CRP was measured at admission, and whose infection focus was known, were included. Electronic medical and microbiological records were reviewed.

RESULTS

Of the 832 bacteremic patients enrolled, 30% had complicated manifestations of pneumococcal disease. Most frequent were pleural effusion (8.9%), pleural empyema (5.4%), and meningitis (7.5%). Compared to solitary pneumonia, patients with pleural effusion and empyema presented with higher CRP levels. Although low CRP did not exclude complicated disease in general, a CRP level < 114 mg/L at admission could reliably exclude empyema among adult pneumonia patients with an NPV of 93% and a specificity of 26%. However, in cases where pleural fluid was present, CRP levels were mostly above 114 mg/L, such that suspicion of empyema could only be ruled out in a minority of cases (10%).

CONCLUSIONS

Complicated manifestations are prevalent in adult pneumococcal bacteraemia. Low blood CRP levels can reliably exclude the development of pulmonary empyema. Practical value may be largest in settings without thoracic imaging at hand.

Clinical relevance of emphysema in patients hospitalized with community-acquired pneumonia: Clinical features and prognosis

INTRODUCTION

Few studies have investigated the influence of emphysema on clinical features of patients presenting with community-acquired pneumonia (CAP).

OBJECTIVES

The aim of this study was to examine the clinical and microbiological features of patients with both CAP and emphysema.

METHODS

This retrospective study included patients with CAP who underwent computed tomography (CT) scan at the time of presentation. Patients were allocated into emphysema and control groups, and clinical variables were compared between the two groups. The emphysema group was further divided into three subgroups (mild, moderate, and severe) according to the extent of emphysema on CT scan. The clinical variables of each subgroup were compared with the control group.

RESULTS

Of 1676 patients, 431 patients (25.7%) were classified into the emphysema group. CAP patients with emphysema were more likely to have a high CURB-65 score and pneumonia severity index and a lower incidence of complicated parapneumonic effusion or empyema. The emphysema group exhibited longer hospital stay. In addition, 30-day mortality in the severe emphysema group was significantly higher compared with the control group. As etiological agents, Streptococcus pneumoniae, Pseudomonas aeruginosa, Enterobacteriaceae, and multidrug-resistant pathogens were significantly more common in the emphysema group compared with the control group.

CONCLUSIONS

The presence of emphysema in CAP patients was associated with a more severe form of CAP, a longer hospital stay, and a lower incidence of complicated parapneumonic effusion or empyema. Moreover, CAP patients with severe emphysema exhibited higher 30-day mortality than those without emphysema.

C-reactive protein influences the doctor's degree of suspicion of pneumonia in primary care: a prospective observational study

BACKGROUND

In primary care, the diagnosis of pneumonia is often based on history and clinical examination alone. However, a previous study showed that the general practitioner's degree of suspicion correlates well with findings on chest X-ray, when the C-reactive protein (CRP) value is known.

OBJECTIVES

The present study aimed to investigate to what extent the physician's degree of suspicion is affected by the CRP level when community-acquired pneumonia is suspected in primary care.

METHODS

A prospective observational study was conducted at five primary health care centres in Sweden between October 2015 and December 2017. Adult patients (n = 266) consulting their health care centre with symptoms of lower respiratory tract infection, where the physician suspected pneumonia, were included consecutively. Anamnestic information and findings from clinical examination were documented in a case report form. All patients were tested for CRP. The physicians rated their degree of suspicion as 'unsure,' 'quite sure,' and 'sure' before and after the CRP result.

RESULTS

The degree of suspicion of pneumonia changed in 69% of the cases; most often to a lower degree (40%). In 28% of the cases, there was no longer any suspicion of pneumonia after CRP.

CONCLUSION

Our results indicate that CRP testing highly influences the physician's degree of suspicion of pneumonia in primary care and that it seems to be of most value when not sure of the diagnosis.

Prognostic factors in elderly patients admitted to the intensive care unit with community-acquired pneumonia

OBJECTIVE

We aimed to determine the clinical, radiological and laboratory findings that may indicate poor prognosis in severe community acquired pneumonia (CAP) requiring intensified care to reduce the risk of death.

METHODS

The medical histories, demographic characteristics and laboratory values of over 65 years old patients admitted to the intensive care unit (ICU) and diagnosed with CAP were recorded.

RESULTS

Total of 86 patients were included in the study. Among those patients 39 were discharged from the ICU with health but 47 were expired. Diastolic blood pressure was significantly lower in expired patients (p = 0.044). In multivariate analysis, older age (>78 years) (p = 0.004), at admission elevated blood glucose (>108 mg/dL) levels (p = 0.048), decreased serum albumin (<3.5 g/dL) levels (p = 0.043), elevated serum procalcitonin levels (>0.63 μg/L) (p = 0.034) and in blood gas analysis decreased pH (<7.35) (p = 0.042)and increased lactate (>2mmol/L) (p = 0.001) were the significant risk factors for in-ICU mortality.

CONCLUSIONS

At old age, blood glucose and procalcitonin levels increased at the time of admission, serum albumin levels decreased, pH decreased in blood gas analysis and lactate levels increased, and significant mortality determinants in CAP patients over 65 years of age who applied to the intensive care unit.

Hospital admissions for community-acquired, ventilator-associated and nonventilator hospital-acquired pneumonia in COPD patients in Spain (2016-2017)

BACKGROUND

To examine the incidence, characteristics and outcomes of community-acquired pneumonia (CAP), ventilator-associated pneumonia (VAP) and nonventilator hospital-acquired pneumonia (NV-HAP) in patients with or without COPD; compare in-hospital outcomes; and identify factors associated with in-hospital mortality (IHM) for pneumonia.

METHODS

We carried out a retrospective observational study using the hospital discharge records from 2016-17 of the Spanish National Health System. Propensity score matching was used for data analysis.

RESULTS

We found 245,905 patients (≥40 years) with pneumonia; we identified CAP in 228,139 patients (19.85% with COPD), VAP in 2,771 patients (8.55% with COPD) and NV-HAP in 14,995 patients (14.17% with COPD). The incidence for the three types of pneumonia was higher in COPD patients (CAP: incidence rate ratio (IRR) 2.23, 95% CI 2.21-2.26; VAP: IRR 1.25, 95% CI 1.08-1.42; and NV-HAP: IRR 1.55, 95% CI 1.48-1.63). The IHM for CAP was 10.35% in COPD patients and 12.91% in the controls (p<0.001). In patients with VAP and NV-HAP, IHM was not significantly different between those with and without COPD (43.88% vs. 41.77%;p=0.643 and 29.21% vs. 30.57%;p=0.331, respectively). Factors associated with IHM for all types of pneumonia analyzed in COPD patients were older age and receiving dialysis.

CONCLUSIONS

The incidence of hospitalizations for all types of pneumonia was significantly higher in COPD patients than in the non-COPD population. In contrast, IHM was significantly lower among COPD patients with CAP than among matched non-COPD patients. Higher mortality rates in COPD patients with any pneumonia type were associated with increasing age and receiving dialysis.

Pneumonic versus Nonpneumonic Exacerbations of Chronic Obstructive Pulmonary Disease

Patients with chronic obstructive pulmonary disease (COPD) often suffer acute exacerbations (AECOPD) and community-acquired pneumonia (CAP), named nonpneumonic and pneumonic exacerbations of COPD, respectively. Abnormal host defense mechanisms may play a role in the specificity of the systemic inflammatory response. Given the association of this aspect to some biomarkers at admission (e.g., C-reactive protein), it can be used to help to discriminate AECOPD and CAP, especially in cases with doubtful infiltrates and advanced lung impairment. Fever, sputum purulence, chills, and pleuritic pain are typical clinical features of CAP in a patient with COPD, whereas isolated dyspnea at admission has been reported to predict AECOPD. Although CAP may have a worse outcome in terms of mortality (in hospital and short term), length of hospitalization, and early readmission rates, this has only been confirmed in a few prospective studies. There is a lack of methodologically sound research confirming the impact of severe AECOPD and COPD + CAP. Here, we review studies reporting head-to-head comparisons between AECOPD and CAP + COPD in hospitalized patients. We focus on the epidemiology, risk factors, systemic inflammatory response, clinical and microbiological characteristics, outcomes, and treatment approaches. Finally, we briefly discuss some proposals on how we should orient research in the future.

Effects of Anaerobic Culturing on Pathogenicity and Virulence-Related Gene Expression in Pneumococcal Pneumonia

BACKGROUND

The pathogenicity of Streptococcus pneumoniae under anaerobic conditions remains largely unknown. We examined the pathogenicity of S. pneumoniae cultured under anaerobic conditions in a murine model of pneumococcal pneumonia.

METHODS

Mice were infected with S. pneumoniae grown under anaerobic or aerobic conditions. The pathogenic effects in vivo in the lower airway tract were then compared. The effect of anaerobic culture on lytA/ply transcript levels in vitro and in vivo were analyzed by quantitative real-time polymerase chain reaction.

RESULTS

Mice inoculated with anaerobically cultured S. pneumoniae exhibited significantly lower survival rates and higher bacterial loads in the lungs and blood as compared to those infected with aerobically cultured S. pneumoniae. Aerobically cultured S. pneumoniae in the early log phase of growth was also able to induce severe pneumonia at levels equivalent to those of anaerobic S. pneumoniae. However, ply/gyrB transcript levels were significantly increased in the lungs of mice infected with anaerobically grown S. pneumoniae. In vitro, S. pneumoniae grown under anaerobic culture conditions demonstrated greater proliferation than S. pneumoniae grown under aerobic culture conditions, and bacterial concentrations were maintained for 24 hours without detectable upregulation of lytA messenger RNA.

CONCLUSIONS

S. pneumoniae grown under anaerobic conditions had the potential to induce severe invasive bacteremic pneumococcal pneumonia in a manner different from that of S. pneumoniae grown under aerobic conditions.

Twenty-year trend in mortality among hospitalized patients with pneumococcal community-acquired pneumonia

BACKGROUND

There is only limited information on mortality over extended periods in hospitalized patients with pneumococcal community-acquired pneumonia (CAP). We aimed to evaluate the 30-day mortality and whether is changed over a 20-year period among immunocompetent adults hospitalized with pneumococcal CAP.

METHODS

We conducted a retrospective observational study of data that were prospectively collected at the Hospital Clinic of Barcelona of all adult patients hospitalized with diagnosis of pneumococcal CAP over a 20-year period. To aid analysis, results were divided into four periods of 5 years each (1997-2001, 2002-2006, 2007-2011, 2012-2016). The primary outcome was 30-day mortality, but secondary outcomes included intensive care unit (ICU) admission, lengths of hospital and ICU-stays, ICU-mortality, and need of mechanical ventilation.

RESULTS

From a cohort of 6,403 patients with CAP, we analyzed the data for 1,120 (17%) adults with a diagnosis of pneumococcal CAP. Over time, we observed decreases in the rates of alcohol consumption, smoking, influenza vaccination, and older patients (age ≥65 years), but increases in admissions to ICU and the need for non-invasive mechanical ventilation. The overall 30-day mortality rate was 8% (95% confidence interval, 6%-9%; 84 of 1,120 patients) and did not change significantly between periods (p = 0.33). Although, we observed a decrease in ICU-mortality comparing the first period (26%) to the second one (10%), statistical differences disappeared with adjustment (p0.38).

CONCLUSION

Over time, 30-day mortality of hospitalized pneumococcal CAP did not change significantly. Nor did it change in the propensity-adjusted multivariable analysis. Since mortality in pneumococcal pneumonia has remained unaltered for many years despite the availability of antimicrobial agents with proven in vitro activity, other non-antibiotic strategies should be investigated.

Acute respiratory distress syndrome in mechanically ventilated patients with community-acquired pneumonia

Our aim was to assess the incidence, characteristics, aetiology, risk factors and mortality of acute respiratory distress syndrome (ARDS) in intensive care unit (ICU) patients with community-acquired pneumonia (CAP) using the Berlin definition.We prospectively enrolled consecutive mechanically ventilated adult ICU patients with CAP over 20 years, and compared them with mechanically ventilated patients without ARDS. The main outcome was 30-day mortality.Among 5334 patients hospitalised with CAP, 930 (17%) were admitted to the ICU and 432 required mechanical ventilation; 125 (29%) cases met the Berlin ARDS criteria. ARDS was present in 2% of hospitalised patients and 13% of ICU patients. Based on the baseline arterial oxygen tension/inspiratory oxygen fraction ratio, 60 (48%), 49 (40%) and 15 (12%) patients had mild, moderate and severe ARDS, respectively. Streptococcus pneumoniae was the most frequent pathogen, with no significant differences in aetiology between groups. Higher organ system dysfunction and previous antibiotic use were independent risk factors for ARDS in the multivariate analysis, while previous inhaled corticosteroids were independently associated with a lower risk. The 30-day mortality was similar between patients with and without ARDS (25% versus 30%, p=0.25), confirmed by propensity-adjusted multivariate analysis.ARDS occurs as a complication of CAP in 29% of mechanically ventilated patients, but is not related to the aetiology or mortality.

Chest imaging for the diagnosis of complicated parapneumonic effusions

PURPOSE OF REVIEW

To provide an overview of the contribution of thoracic ultrasound (TUS) and computed tomography (CT) in the identification of complicated parapneumonic effusions (CPPE), defined as those which need chest tube drainage for resolution.

RECENT FINDINGS

A recent retrospective study found that visualization of complex (nonanechoic) effusions on TUS (likelihood ratio positive = 6.92) outperformed the recognition of loculated/septated effusions on CT (likelihood ratio = 2.20) or chest radiographs (likelihood ratio = 1.54) for predicting a CPPE. In another retrospective study, a weighted CT scoring system consisting of pleural contrast enhancement (three points), pleural microbubbles, increased extrapleural fat attenuation, and fluid volume at least 400 ml (one point each) had relatively good accuracy for labeling CPPE (likelihood ratio positive = 3.4; likelihood ratio negative = 0.22) when four or more points were achieved.

SUMMARY

Although a gold standard for CPPE diagnosis is lacking, bedside TUS primarily, and CT scan in certain circumstances, may help to drive clinical decisions regarding chest tube placement in parapneumonic effusions (PPE). However, recommendations are limited by the absence of prospective trials.

Risk factors for pneumococcal endocarditis

Bacteremia is one of the most common manifestations of invasive pneumococcal disease (IPD). One complication of bacteremia is endocarditis; yet, few studies have evaluated the overall incidence and risk factors for IPD-associated endocarditis. Thus, we evaluated the overall incidence and risk factors of endocarditis compared to those without endocarditis in a large population of IPD patients. We prospectively collected all IPD cases from 2000 to 2014 in Northern Alberta, Canada. Descriptive statistics were used to compare sociodemographic variables, clinical characteristics, and IPD-related outcomes between patients with and without endocarditis. Endocarditis complicated the course of only 28 (0.3%) of 3251 adult patients with IPD. Endocarditis patients were more likely to use illicit drugs and have a higher severity of illness at presentation (i.e., higher rate of altered mental status and rate of intensive care unit [ICU] utilization, p < 0.05); however, no other major risk factors were identified. New murmur development among endocarditis patients was common: 39.3% compared to 2.2% of non-endocarditis patients (p < 0.001). The mortality rate of 39.3% was more than twice that of the rate of 14.7% for the patients with IPD but without endocarditis. There was no pneumococcal serotype predilection for endocarditis. Endocarditis is an uncommon complication of IPD, but, when present, is associated with a significantly increased risk of mortality. Overall, few specific risk factors were identified for IPD-related endocarditis, with the exception of illicit drug use.

Outcomes of Critically Ill Patients Who Have Serotype 5 Invasive Pneumococcal Disease

PURPOSE

To determine whether invasive pneumococcal disease (IPD) due to serotype 5, which occurred as a local outbreak in 2006 to 2007, is associated with intensive care unit (ICU) admission, hospital mortality, or organ supports in those who are critically ill.

MATERIALS AND METHODS

Retrospective review of patients who presented with IPD to 2 tertiary hospitals in Vancouver, Canada, from July 2004 to June 2007. We compared patient characteristics, interventions, and outcomes between patients who had serotype 5 and other serotypes using bivariate and multivariate analyses.

RESULTS

A total of 149 patients had serotype 5 and 106 had nonserotype 5. Patients with serotype 5 were younger, had lower prevalence of comorbid diseases, and had higher rates of substance use than patients with nonserotype 5. There were no differences in chest tube placement for complications of pneumonia or in ICU admission. Frequency of necrotizing pneumonia and hospital mortality were lower in the serotype 5 group. For the 71 patients with IPD who were admitted to ICU, there was no difference in severity of illness, ICU length of stay, or ICU mortality between the groups. There was also no difference in organ supports except that the serotype 5 group was more likely to receive vasopressors.

CONCLUSION

Serotype 5 in patients who have IPD is associated with no difference in ICU admission but with increased use of vasopressors and lower hospital mortality.

Impact of COPD on outcomes in hospitalized patients with community-acquired pneumonia: Analysis of the Spanish national hospital discharge database (2004-2013)

AIM

To examine trends in incidence and outcomes of community-acquired pneumonia (CAP) hospitalizations among patients with or without COPD in Spain (2004-2013).

METHODS

We used national hospital discharge data to select all hospital admissions for CAP. Incidence was calculated overall and according to the presence or absence of COPD.

RESULTS

We identified 901,136 hospital admissions for CAP (32.25% with COPD). Incidence of hospitalizations of CAP increased significantly over time among patients with and without COPD, but it was higher among people with COPD for all years analyzed. S. pneumoniae decreased over time for both groups. Time trend analyses showed significant decreases in mortality during admission for CAP for patients with and without COPD. Factor independently associated with higher mortality in both groups included: male sex, older age, higher comorbidity, isolation of S. aureus or P. aeruginosa, use of mechanical ventilation, and readmission. The presence of COPD was associated with a lower in-hospital mortality (IHM) (OR: 0.58, 95%CI 0.57-0.59).

CONCLUSIONS

The incidence of hospitalizations for CAP increased over time in patients with and without COPD, being higher in the COPD population for all years analyzed. IHM decreased over time in both groups. There were no differences in mortality between COPD and non-COPD patients.

The burden of PCV13 serotypes in hospitalized pneumococcal pneumonia in Spain using a novel urinary antigen detection test. CAPA study

BACKGROUND

Streptococcus pneumoniae serotypes distribution in community-acquired pneumonia (CAP) requiring hospitalization in adults after introduction of PCV13 in children is not well known. Our aim was to evaluate the distribution of serotypes in pneumococcal pneumonia according to risk factors and comorbidity conditions after the introduction of PCV13 in children in 2010.

METHODS

A prospective study from 2011 to 2014 was performed in immunocompetent adults hospitalized with CAP in 3 Spanish hospitals. Microbiological confirmation was obtained using a serotype specific urinary antigen detection test (UAD test), Binax Now and conventional cultures.

RESULTS

1258 adults were enrolled and pneumococcal pneumonia (invasive disease in 17.7%) was confirmed in 368 (29.3%) and 17.6% of the any-cause CAP were caused by PVC13 serotypes (3.5% PCV7 serotypes). Around 60% of pneumococcal CAP were caused by PCV13 serotypes (74.6% in invasive episodes vs 57.4% in non-invasive ones). The most prevalent serotypes in invasive disease were 1, 3, 7F, 19A and 14. No significant differences were observed in the distribution of PCV13 serotypes across the study periods. Regarding comorbidity, the rate of PCV13 serotypes was similar among them, and it was slightly higher in those with no underlying conditions.

CONCLUSIONS

Serotypes included in PCV13 caused a significant proportion of CAP in adults with underlying conditions and in healthy adults, with no significant changes in cases due to PCV7 or PCV13 from 2011 to 2014, suggesting an insufficient indirect protection from childhood vaccination. Strategies for implementing pneumococcal vaccination of adults are encouraged to reduce the incidence of pneumococcal episodes.

Antibiotic therapy prior to hospital admission is associated with reduced septic shock and need for mechanical ventilation in patients with community-acquired pneumonia

A subgroup of patients admitted to the hospital with a diagnosis of community-acquired pneumonia (CAP) have received antibiotic therapy prior to admission for the current episode of pneumonia. The objective of this study was to assess the clinical course of patients receiving antibiotics prior to admission, compared to patients not previously treated. An observational cohort of 3364 CAP patients consecutively admitted to our hospital, and prospectively included, were studied. We collected clinical, microbiological and biochemical parameters, focusing on recent antibiotics received prior to admission. 610 (18%) patients received antibiotics prior to hospital admission for the current CAP episode. Patients with previous antibiotic use developed septic shock less frequently (4% vs. 7%, p = 0.007) and required invasive ventilation less often (3% vs. 6%, p = 0.002). After adjustment by different covariate factors and propensity score, antibiotic therapy was still independently associated with a lower incidence of septic shock at admission (OR 0.54 [95% CI 0.31-0.95], p = 0.03) and less need for invasive ventilation (OR 0.38 [95% CI 0.16-0.91], p = 0.03). In this cohort, recent use of antibiotics before hospital admission in CAP seems to be associated with a lower incidence of septic shock on admission and a lower need for invasive ventilation.

Invasive Disease vs Urinary Antigen-Confirmed Pneumococcal Community-Acquired Pneumonia

BACKGROUND

The burden of pneumococcal disease is measured only through patients with invasive pneumococcal disease. The urinary antigen test (UAT) for pneumococcus has exhibited high sensitivity and specificity. We aimed to compare the pneumococcal pneumonias diagnosed as invasive disease with pneumococcal pneumonias defined by UAT results.

METHODS

A prospective observational study of consecutive nonimmunosuppressed patients with community-acquired pneumonia was performed from January 2000 to December 2014. Patients were stratified into two groups: invasive pneumococcal pneumonia (IPP) defined as a positive blood culture or pleural fluid culture result and noninvasive pneumococcal pneumonia (NIPP) defined as a positive UAT result with negative blood or pleural fluid culture result.

RESULTS

We analyzed 779 patients (15%) of 5,132, where 361 (46%) had IPP and 418 (54%) had NIPP. Compared with the patients with IPP, those with NIPP presented more frequent chronic pulmonary disease and received previous antibiotics more frequently. Patients with IPP presented more severe community-acquired pneumonia, higher levels of inflammatory markers, and worse oxygenation at admission; more pulmonary complications; greater extrapulmonary complications; longer time to clinical stability; and longer length of hospital stay compared with the NIPP group. Age, chronic liver disease, mechanical ventilation, and acute renal failure were independent risk factors for 30-day crude mortality. Neither IPP nor NIPP was an independent risk factor for 30-day mortality.

CONCLUSIONS

A high percentage of confirmed pneumococcal pneumonia is diagnosed by UAT. Despite differences in clinical characteristics and outcomes, IPP is not an independent risk factor for 30-day mortality compared with NIPP, reinforcing the importance of NIPP for pneumococcal pneumonia.

Risk factors for local complications in children with community-acquired pneumonia

AIM

The aim of this study was to evaluate the factors that could predict the development of local complications (parapneumonic effusion/pleural empyema, necrotizing pneumonia, and lung abscess) in children with community-acquired pneumonia (CAP).

METHODS

Demographic, clinical, and laboratory data were prospectively collected and compared in children with noncomplicated and complicated CAP.

RESULTS

Two-hundred and three patients aged from 2 months to 17 years were enrolled. There were 141 and 62 children with noncomplicated and complicated CAP, respectively. Significantly longer duration of fever and a higher level of acute phase reactants were demonstrated in complicated when noncomplicated to complicated CAP. Asymmetric chest pain as well as prehospital treatment with ibuprofen and acetaminophen were significantly more common in patients with complicated CAP (P < .001, P = .02 and P = .003, respectively). Preadmission cumulative dose of ibuprofen exceeding 78.3 mg/kg (median dose for the entire group) was associated with 2.5-fold higher odds ratio (OR) for CAP complications [OR 2.54 CI (1.31-4.94); P = .008)]. In contrast, pneumococcal vaccination was associated with lower odds ratio [OR.03 CI (.23-.89); P = .03] for local complications.

CONCLUSIONS

Some clinical and laboratory data including chest pain, longer duration of fever, higher acute phase reactants, and especially preadmission treatment with ibuprofen or acetaminophen were associated with local complications of CAP. The results of this study highlight the association between the dose of ibuprofen and local CAP complications.

The potential role of 13-valent pneumococcal conjugate vaccine in preventing respiratory complications in bacteraemic pneumococcal community-acquired pneumonia

INTRODUCTION

Pneumococcal 13-valent vaccine (PCV-13) has a potential role in preventing bacteraemic pneumococcal pneumonia and its complications, but little is known about its ability to specifically prevent respiratory complications. Our aim were to analyse the pneumococcal serotypes associated with the development of respiratory complications and the potential role of PCV-13 in preventing respiratory complications in bacteraemic pneumococcal pneumonia.

MATERIAL AND METHODS

We analysed demographic characteristics, comorbidities, antibiotic resistances and the outcomes of a cohort of 65 vaccine-naïve bacteraemic pneumococcal pneumonias, stratified by the pneumococcal serotypes included in PCV13 vs. those not included. Complications were clustered as follows: respiratory complications (hypoxemic respiratory failure; mechanical ventilation), systemic complications (septic shock; multiorgan failure), suppurative complications (empyema; pleural effusion; lung abscess).

RESULTS

From a population of 65 CAP-SP, 47.7% of the isolates belonged to PCV-13 serotypes group. No differences in comorbidities or clinical manifestations were found between groups. With regard to biochemical parameters, we found more profound hypoxemia levels in PCV-13 serotypes group comparing to non-vaccine group [PaO2/FiO2 209 (63) vs. 268 (57); p=0.007]. Global complications were identified in 69.2% (45 patients), and the most frequent were respiratory complications, found in 47.7%. Respiratory complications were detected more frequently in PCV-13 groups compared to non-vaccine groups (61.3% vs. 35.3%; p=0.036). Overall 30-day mortality was 30.8%. Mortality was similar between both groups (25.8% vs. 35.3%; p=0.408).

CONCLUSIONS

Pneumococcal 13-valent conjugate vaccine includes the serotypes which cause more respiratory complications in our series; these serotypes were not associated with higher mortality in our series. PCV-13 may have a potential role in preventing respiratory complications due to bacteraemic pneumonoccal pneumonia.

Usefulness of pneumococcal antigen urinary testing in the intensive care unit?

OBJECTIVES

The use of pneumococcal antigen urinary tests is substantially increasing and is associated with a significant cost. The relevant use of this test in the intensive care unit (ICU) should be better defined. Our aim was to define the role of this test in relation to other microbiological tests. We described a series of patients admitted to the ICU for an invasive pneumococcal disease (IPD).

PATIENTS AND METHODS

We conducted a retrospective and descriptive study of the microbiological tests used to diagnose IPD in patients admitted to the ICU of the University Hospital in Bordeaux. Our aim was to measure the sensitivity of these bacteriological tests and of the BinaxNOWS. pneumoniae test.

RESULTS

Between 2009 and 2013, 148 patients were admitted for an IPD. A lower respiratory tract infection was diagnosed in 96.6% of them (143 patients). The overall ICU case fatality rate was 17.6%. The sensitivity of the pneumococcal antigen urinary test, sputum bacteriological examination, and blood cultures was respectively 83%, 37.6%, and 29.7%. S. pneumoniae was isolated from at least one bacteriological sample in 48.6% of patients, but in 51.4%, the diagnosis was only based on the results of the pneumococcal antigen urinary test.

CONCLUSION

We suggest performing a pneumococcal antigen urinary test when an IPD is suspected, only if the bacteriological tests are still negative after 48hours. This strategy would result in a substantial cost saving. Patients would not face any additional risks as the result of the pneumococcal antigen urinary test does not have any impact on the initially prescribed antibiotic therapy.

Allergic Lung Inflammation Reduces Tissue Invasion and Enhances Survival from Pulmonary Pneumococcal Infection in Mice, Which Correlates with Increased Expression of Transforming Growth Factor β1 and SiglecF(low) Alveolar Macrophages

Asthma is generally thought to confer an increased risk for invasive pneumococcal disease (IPD) in humans. However, recent reports suggest that mortality rates from IPD are unaffected in patients with asthma and that chronic obstructive pulmonary disease (COPD), a condition similar to asthma, protects against the development of complicated pneumonia. To clarify the effects of asthma on the subsequent susceptibility to pneumococcal infection, ovalbumin (OVA)-induced allergic lung inflammation (ALI) was induced in mice followed by intranasal infection with A66.1 serotype 3 Streptococcus pneumoniae. Surprisingly, mice with ALI were significantly more resistant to lethal infection than non-ALI mice. The heightened resistance observed following ALI correlated with enhanced early clearance of pneumococci from the lung, decreased bacterial invasion from the airway into the lung tissue, a blunted inflammatory cytokine and neutrophil response to infection, and enhanced expression of transforming growth factor β1 (TGF-β1). Neutrophil depletion prior to infection had no effect on enhanced early bacterial clearance or resistance to IPD in mice with ALI. Although eosinophils recruited into the lung during ALI appeared to be capable of phagocytizing bacteria, neutralization of interleukin-5 (IL-5) to inhibit eosinophil recruitment likewise had no effect on early clearance or survival following infection. However, enhanced resistance was associated with an increase in levels of clodronate-sensitive, phagocytic SiglecF(low) alveolar macrophages within the airways following ALI. These findings suggest that, while the risk of developing IPD may actually be decreased in patients with acute asthma, additional clinical data are needed to better understand the risk of IPD in patients with different asthma phenotypes.

Low C-reactive protein values at admission predict mortality in patients with severe community-acquired pneumonia caused by Streptococcus pneumoniae that require intensive care management

Purpose

To identify risk factors associated with mortality in patients with severe community-acquired pneumonia (CAP) caused by S. pneumoniae who require intensive care unit (ICU) management, and to assess the prognostic values of these risk factors at the time of admission.

Methods

Retrospective analysis of all consecutive patients with CAP caused by S. pneumoniae who were admitted to the 32-bed medico-surgical ICU of a community and referral university hospital between 2002 and 2011. Univariate and multivariate analyses were performed on variables available at admission.

Results

Among the 77 adult patients with severe CAP caused by S. pneumoniae who required ICU management, 12 patients died (observed mortality rate 15.6 %). Univariate analysis indicated that septic shock and low C-reactive protein (CRP) values at admission were associated with an increased risk of death. In a multivariate model, after adjustment for age and gender, septic shock [odds ratio (OR), confidence interval 95 %; 4.96, 1.11–22.25; p = 0.036], and CRP (OR 0.99, 0.98–0.99 p = 0.034) remained significantly associated with death. Finally, we assessed the discriminative ability of CRP to predict mortality by computing its receiver operating characteristic curve. The CRP value cut-off for the best sensitivity and specificity was 169.5 mg/L to predict hospital mortality with an area under the curve of 0.72 (0.55–0.89).

Conclusions

The mortality of patients with S. pneumoniae CAP requiring ICU management was much lower than predicted by severity scores. The presence of septic shock and a CRP value at admission <169.5 mg/L predicted a fatal outcome.

Do we measure pleural fluid pH correctly?

PURPOSE OF REVIEW

This review analyzes the current literature available on appropriate measurement of pleural fluid pH and currently used methods of measurement.

RECENT FINDINGS

Current literature continues to support the superiority of blood gas analyzers (BGAs) in the accurate measurement of pleural fluid pH. Despite the compelling evidence, roughly 30-50% of the laboratories across the United States continue to use inaccurate methods for pleural fluid pH measurement. Nearly 40% of pulmonologists were incorrect in believing their laboratory uses BGA for the analysis of pleural fluid pH.

SUMMARY

It is apparent that the clinical utility of pleural fluid pH is often undermined by its inappropriate measurement. Physicians must be made aware of their laboratory's method of measurement if pleural fluid pH is to be used in the evaluation of pleural diseases. If pleural fluid pH measurement is not done accurately, then other pleural fluid characteristics may be used to aid the clinician.

Pneumococcal empyema and complicated pneumonias: global trends in incidence, prevalence, and serotype epidemiology

This review evaluates the serotype epidemiology of complicated pneumococcal pneumonia (CPP) during the period 1990–2012. PubMed and EMBASE were searched using the terms “empyema”, “complicated pneumonia”, “pleural infection”, “necrotizing pneumonia”, “pleural effusion”, “parapneumonic effusion”, “pneumatocele”, or “lung abscess”; “pneumococcal” or “Streptococcus pneumoniae”; and “serotype” for studies on the epidemiology of complicated pneumonias published from January 1, 1990 to October 1, 2013. Studies with data on incidence and serotypes were included; reviews, case reports, and conference abstracts were excluded. Of 152 papers, 84 fitted the inclusion criteria. A few pneumococcal serotypes were predominant causes of CPP, particularly serotypes 1, 19A, 3, 14, and 7F. CPP was a more common manifestation of pneumococcal disease among older (>2 years old) than younger children. The data support increases in both reported incidence rates and proportions of CPP in children and adults during the period 1990–2012; specific increases varied by geographic region. The proportions of serotype 3 and, particularly in Asia, serotype 19A CPP have increased, whereas most studies show declines in serotype 14. Serotype 1 has been a predominant cause of CPP since 1990, while antibiotic resistance was infrequent among serotype 1 isolates. The reported incidence and proportions of CPP among pneumonia cases steadily increased from 1990 to 2012. Several factors might account for these increases, including enhanced disease detection due to a higher index of suspicion, more sophisticated diagnostic assays, and changes in the prevalence of serotypes with capacity to invade the pleural space that were not targeted by the 7-valent pneumococcal conjugate vaccine (PCV7).

The aetiology and antibiotic management of community-acquired pneumonia in adults in Europe: a literature review

The purpose of this paper was to generate up-to-date information on the aetiology of community-acquired pneumonia (CAP) and its antibiotic management in adults across Europe. Structured searches of PubMed identified information on the aetiology of CAP and its antibiotic management in individuals aged >15 years across Europe. We summarise the data from 33 studies published between January 2005 and July 2012 that reported on the pathogens identified in patients with CAP and antibiotic treatment in patients with CAP. Streptococcus pneumoniae was the most commonly isolated pathogen in patients with CAP and was identified in 12.0–85.0 % of patients. Other frequently identified pathogens found to cause CAP were Haemophilus influenzae, Gram-negative enteric bacilli, respiratory viruses and Mycoplasma pneumoniae. We found several age-related trends: S. pneumoniae, H. influenzae and respiratory viruses were more frequent in elderly patients aged ≥65 years, whereas M. pneumoniae was more frequent in those aged <65 years. Antibiotic monotherapy was more frequent than combination therapy, and beta-lactams were the most commonly prescribed antibiotics. Hospitalised patients were more likely than outpatients to receive combination antibiotic therapy. Limited data on antibiotic resistance were available in the studies. Penicillin resistance of S. pneumoniae was reported in 8.4–20.7 % of isolates and erythromycin resistance was reported in 14.7–17.1 % of isolates. Understanding the aetiology of CAP and the changing pattern of antibiotic resistance in Europe, together with an increased awareness of the risk factors for CAP, will help clinicians to identify those patients most at risk of developing CAP and provide guidance on the most appropriate treatment.

Risk factors for community-acquired pneumonia in adults in Europe: a literature review

Background

Community-acquired pneumonia (CAP) causes considerable morbidity and mortality in adults, particularly in the elderly.

Methods

Structured searches of PubMed were conducted to identify up-to-date information on the incidence of CAP in adults in Europe, as well as data on lifestyle and medical risk factors for CAP.

Results

The overall annual incidence of CAP in adults ranged between 1.07 to 1.2 per 1000 person-years and 1.54 to 1.7 per 1000 population and increased with age (14 per 1000 person-years in adults aged ≥65 years). Incidence was also higher in men than in women and in patients with chronic respiratory disease or HIV infection. Lifestyle factors associated with an increased risk of CAP included smoking, alcohol abuse, being underweight, having regular contact with children and poor dental hygiene. The presence of comorbid conditions, including chronic respiratory and cardiovascular diseases, cerebrovascular disease, Parkinson's disease, epilepsy, dementia, dysphagia, HIV or chronic renal or liver disease all increased the risk of CAP by twofold to fourfold.

Conclusion

A range of lifestyle factors and underlying medical conditions are associated with an increased risk of CAP in European adults. Understanding of the types of individual at greatest risk of CAP can help to ensure that interventions to reduce the risk of infection and burden of disease are targeted appropriately.

Lung abscess complicating pneumococcal pneumonia: a causal role of non-steroidal anti-inflammatory drugs?

Pulmonary abscess is a distinctly uncommon complication of pneumococcal pneumonia in immunocompetent adults that has recently been reported to occur following administration of non-steroidal anti-inflammatory drugs (NSAIDs). We report herein the case of a 24-year-old patient with no predisposing risk factor who developed a lung abscess after NSAIDs exposure, further illustrating this potentially severe complication of NSAIDs use, especially in the absence of associated antibiotic therapy.