Community-acquired pneumonia and nursing home-acquired pneumonia in the very elderly patients

Decoding community-acquired pneumonia: a systematic review and analysis of diagnostic criteria and definitions used in clinical trials

BACKGROUND

Community-acquired pneumonia (CAP) is a frequent and potentially life-threatening condition. Even though the disease is common, evidence on CAP management is often of variable quality. This may be reinforced by the lack of a systematic and homogeneous way of defining the disease in randomized controlled trials (RCTs).

OBJECTIVES

This study aims to assess the diagnostic criteria and definitions of the term 'community-acquired' used in RCTs on CAP management.

DATA SOURCES

On the basis of the protocol (PROSPERO 2019 CRD42019147411), we conducted a systematic search of Medline/PubMed and the Cochrane Register of Controlled Trials for RCTs published or registered between 2010 and 2024.

STUDY ELIGIBILITY CRITERIA

Study eligibility criteria included completed and ongoing RCTs.

PARTICIPANTS

Participants included adults hospitalized with CAP.

METHODS OF DATA SYNTHESIS

Data were collected using a tested extraction sheet, as endorsed by the Cochrane Collaboration. After cross-checking, data were synthesized in a narrative and tabular form.

RESULTS

In total, 7173 records were identified through our searches. After removing records that did not fulfil the eligibility criteria, 170 studies were included. Diagnostic criteria were provided in 69.4% of studies, and the term 'community-acquired' was defined in 55.3% of studies. The most frequently included diagnostic criteria were pulmonary infiltrates (94.1%), cough (78.8%), fever (77.1%), dyspnoea (62.7%), sputum (57.6%), auscultation/percussion abnormalities (55.9%), and chest pain/discomfort (52.5%). The different criteria were used in 87 different sets across the studies. The term 'community-acquired' was defined in 57 different ways.

CONCLUSIONS

The diagnostic criteria and definitions of CAP in RCTs exhibit significant heterogeneity. Standardizing these criteria in clinical trials is crucial to ensure comparability across studies.

Aetiological agents of adult community-acquired pneumonia in Japan: systematic review and meta-analysis of published data

OBJECTIVE

Epidemiological information is essential in providing appropriate empiric antimicrobial therapy for pneumonia. This study aimed to clarify the epidemiology of community-acquired pneumonia (CAP) by conducting a systematic review of published studies in Japan.

DESIGN

Systematic review.

DATA SOURCE

PubMed and Ichushi web database (January 1970 to October 2022).

ELIGIBILITY CRITERIA

Clinical studies describing pathogenic micro-organisms in CAP written in English or Japanese, excluding studies on pneumonia other than adult CAP, investigations limited to specific pathogens and case reports.

DATA EXTRACTION AND SYNTHESIS

Patient setting (inpatient vs outpatient), number of patients, concordance with the CAP guidelines, diagnostic criteria and methods for diagnosing pneumonia pathogens as well as the numbers of each isolate. A meta-analysis of various situations was performed to measure the frequency of each aetiological agent.

RESULTS

Fifty-six studies were included and 17 095 cases of CAP were identified. Pathogens were undetectable in 44.1% (95% CI 39.7% to 48.5%). Streptococcus pneumoniae was the most common cause of CAP requiring hospitalisation or outpatient care (20.0% (95% CI 17.2% to 22.8%)), followed by Haemophilus influenzae (10.8% (95% CI 7.3% to 14.3%)) and Mycoplasma pneumoniae (7.5% (95% CI 4.6% to 10.4%)). However, when limited to CAP requiring hospitalisation, Staphylococcus aureus was the third most common at 4.9% (95% CI 3.9% to 5.8%). Pseudomonas aeruginosa was more frequent in hospitalised cases, while atypical pathogens were less common. Methicillin-resistant S. aureus accounted for 40.7% (95% CI 29.0% to 52.4%) of S. aureus cases. In studies that used PCR testing for pan-respiratory viral pathogens, human enterovirus/human rhinovirus (9.4% (95% CI 0% to 20.5%)) and several other respiratory pathogenic viruses were detected. The epidemiology varied depending on the methodology and situation.

CONCLUSION

The epidemiology of CAP varies depending on the situation, such as in the hospital versus outpatient setting. Viruses are more frequently detected by exhaustive genetic searches, resulting in a significant variation in epidemiology.

Biomarkers for Lipid and Albumin Metabolism in Hospitalized Patients with Underlying Diseases and Community-Acquired Pneumonia Caused by Bacterial or SARS-CoV-2 Infection

Background

To look at the differences and similarities in albumin and lipid metabolism in non-severe COVID-19 infection, non-severe community-acquired pneumonia, and severe community pneumonia with underlying diseases, as well as the relationship between albumin and lipid metabolism and inflammatory mediators.

Methods

This retrospective analysis comprised 253 individuals with bacterial pneumonia and COVID-19 infection (1 May 2021-1 May 2022). Routine blood examination, blood lipid levels, albumin level, C-reactive protein (CRP) levels, coagulation function, cardiac enzymes, liver function, renal function, immunological function, and bacterial culture were also collected. Correlation analysis was performed using Spearman's test for lipid parameter and Inflammatory factors in the blood. Furthermore, the multiple linear regression (MLR) analysis was employed to analyze the multicollinearity in lipidomics data. The statistical analysis was performed using SPSS statistic version 19.0.

Results

There were 63 (24.90%) non-severe community-acquired pneumonia patients (NSCAP), 48 (18.97%) severe community-acquired pneumonia patients (SCAP), 112 (44.27%) non-severe COVID-19 infection patients (NSCOV), and 30 (11.86%) healthy volunteers (HV). In all, 45.59% (116/253) of the patients had underlying diseases. Patients with community-acquired pneumonia had lower albumin and cholesterol levels than those with non-severe COVID-19 infection and healthy controls (t = -3.81, -2.09, P = 0.00, 0.04). Albumin, triglyceride, cholesterol, and LDL-C levels in peripheral blood were considerably lower in the SCAP group than in the NSCAP group. Albumin, cholesterol, HDL-C, LDL-C, and aop-A were all inversely connected with CRP in the SCAP with underlying illness group, but cholesterol level was favorably correlated with lymphocyte count (R = 0.36, P = 0.01). Hypoproteinemia, hypotriglyceridemia, and an elevated neutrophil-to-lymphocyte count ratio are all risk factors for severe community-acquired pneumonia.

Conclusion

Hypoalbuminemia and abnormal lipid metabolism are important indicators of bacterial infection, especially severe bacterial pneumonia.

Protein C activity as a potential prognostic factor for nursing home-acquired pneumonia

Introduction

Despite the poor prognosis for nursing home acquired pneumonia (NHAP), a useful prognostic factor is lacking. We evaluated protein C (PC) activity as a predictor of in-hospital death in patients with NHAP and community-acquired pneumonia (CAP).

Methods

This prospective, observational study included all patients hospitalized with pneumonia between July 2007 and December 2012 in a single hospital. We measured PC activity at admission and investigated whether it was different between survivors and non-survivors. We also examined whether PC activity < 55% was a predictor for in-hospital death of pneumonia by logistic regression analysis with CURB-65 items (confusion, blood urea >20 mg/dL, respiratory rate >30/min, and blood pressure <90/60 mmHg, age >65). When it was a useful prognostic factor for pneumonia, we combined PC activity with the existing prognostic scores, the pneumonia severity index (PSI) and CURB-65, and analyzed its additional effect by comparing the areas under the receiver operating characteristic curves (AUCs) of the modified and original scores.

Results

Participants comprised 75 NHAP and 315 CAP patients. PC activity was lower among non-survivors than among survivors in NHAP and all-pneumonia (CAP+NHAP). PC activity <55% was a useful prognostic predictor for NHAP (Odds ratio 7.39 (95% CI; 1.59–34.38), and when PSI or CURB-65 was combined with PC activity, the AUC improved (from 0.712 to 0.820 for PSI, and 0.657 to 0.734 for CURB-65).

Conclusions

PC activity was useful for predicting in-hospital death of pneumonia, especially in NHAP, and became more useful when combined with the PSI or CURB-65.

Development and validation of a new scoring system for prognostic prediction of community-acquired pneumonia in older adults

The discriminative power of CURB-65 for mortality in community-acquired pneumonia (CAP) is suspected to decrease with age. However, a useful prognostic prediction model for older patients with CAP has not been established. This study aimed to develop and validate a new scoring system for predicting mortality in older patients with CAP. We recruited two prospective cohorts including patients aged ≥ 65 years and hospitalized with CAP. In the derivation (n = 872) and validation cohorts (n = 1,158), the average age was 82.0 and 80.6 years and the 30-day mortality rate was 7.6% (n = 66) and 7.4% (n = 86), respectively. A new scoring system was developed based on factors associated with 30-day mortality, identified by multivariate analysis in the derivation cohort. This scoring system named CHUBA comprised five variables: confusion, hypoxemia (SpO₂ ≤ 90% or PaO₂ ≤ 60 mmHg), blood urea nitrogen ≥ 30 mg/dL, bedridden state, and serum albumin level ≤ 3.0 g/dL. With regard to 30-day mortality, the area under the receiver operating characteristic curve for CURB-65 and CHUBA was 0.672 (95% confidence interval, 0.607–0.732) and 0.809 (95% confidence interval, 0.751–0.856; P < 0.001), respectively. The effectiveness of CHUBA was statistically confirmed in the external validation cohort. In conclusion, a simpler novel scoring system, CHUBA, was established for predicting mortality in older patients with CAP.

Effect of Poor Nutritional Status and Comorbidities on the Occurrence and Outcome of Pneumonia in Elderly Adults

Background: Malnutrition and comorbidity are two common geriatric syndromes. The pathology of pneumonia is multifactorial, making its diagnosis and management a great challenge. Hospital-acquired pneumonia (HAP) and community-acquired pneumonia (CAP) are two main types of pneumonia. However, the effect of geriatric syndromes on pneumonia and its prognosis have not been clearly explored. Methods: We collected the relevant electronic data of inpatients aged over 65 years and diagnosed with pneumonia in the Geriatrics Department Building of the First Affiliated Hospital with Nanjing Medical University between December 2018 and December 2019, and further divided them into HAP group and CAP group. The correlations of age, age-adjusted Charlson Comorbidity Index (aCCI), basic diseases and nutritional indexes (i.e., albumin, electrolyte, hemoglobin) with pneumonia and prognosis were analyzed. We analyzed the associations between infection prognosis/infection level and age, nutritional status, aCCI and underlying diseases, using linear regression model. The box plot was applied to present infection outcome, and the nomogram was built for predicting infection outcomes. We utilized the heat map to show the associations between nutritional status and infection level/outcome in all infected patients, HAP, and CAP. Results: The final study comprised samples of 669 pneumonia patients divided into HAP group (n = 517) and CAP group (n = 152). In all patients, the infection outcome was negatively correlated with age (P = 0.013). The level of albumin was negatively correlated with infection prognosis in all patients (P = 0.03), and negatively correlated with neutrophil count and CRP (P = 0.008, P < 0.001). ACCI was positively correlated with CRP (P = 0.003). The prognosis was negatively associated with age and albumin level. In the patients with basic dementia/Alzheimer's disease and chronic obstructive pulmonary disease/asthma, the prognosis was worse. Conclusion: There was a correlation between poor nutritional status-related indexes and inflammatory indexes. A poor nutritional status might predict a high risk of pneumonia in elderly adults. Advanced age and comorbidities were risk factors for the occurrence and poor prognosis of pneumonia. Therefore, comorbidities should be well-treated in the elderly with pneumonia.

Hospital utilization rates for influenza and RSV: a novel approach and critical assessment

BACKGROUND

Influenza and respiratory syncytial virus (RSV) contribute significantly to the burden of acute lower respiratory infection (ALRI) inpatient care, but heterogeneous coding practices and availability of inpatient data make it difficult to estimate global hospital utilization for either disease based on coded diagnoses alone.

METHODS

This study estimates rates of influenza and RSV hospitalization by calculating the proportion of ALRI due to influenza and RSV and applying this proportion to inpatient admissions with ALRI coded as primary diagnosis. Proportions of ALRI attributed to influenza and RSV were extracted from a meta-analysis of 360 total sources describing inpatient hospital admissions which were input to a Bayesian mixed effects model over age with random effects over location. Results of this model were applied to inpatient admission datasets for 44 countries to produce rates of hospital utilization for influenza and RSV respectively, and rates were compared to raw coded admissions for each disease.

RESULTS

For most age groups, these methods estimated a higher national admission rate than the rate of directly coded influenza or RSV admissions in the same inpatient sources. In many inpatient sources, International Classification of Disease (ICD) coding detail was insufficient to estimate RSV burden directly. The influenza inpatient burden estimates in older adults appear to be substantially underestimated using this method on primary diagnoses alone. Application of the mixed effects model reduced heterogeneity between countries in influenza and RSV which was biased by coding practices and between-country variation.

CONCLUSIONS

This new method presents the opportunity of estimating hospital utilization rates for influenza and RSV using a wide range of clinical databases. Estimates generally seem promising for influenza and RSV associated hospitalization, but influenza estimates from primary diagnosis seem highly underestimated among older adults. Considerable heterogeneity remains between countries in ALRI coding (i.e., primary vs non-primary cause), and in the age profile of proportion positive for influenza and RSV across studies. While this analysis is interesting because of its wide data utilization and applicability in locations without laboratory-confirmed admission data, understanding the sources of variability and data quality will be essential in future applications of these methods.

The relationship between body mass index and N-terminal pro-B-type natriuretic peptide in community-acquired pneumonia

BACKGROUND

The relationship between body mass index (BMI) and N-terminal pro-B-type natriuretic peptide (NT-proBNP) has not been fully investigated in patients with community-acquired pneumonia (CAP).

METHODS

This prospective observational study examined 510 consecutive patients hospitalized for CAP. NT-proBNP, BMI, and the pneumonia severity index (PSI) were determined for all participants. The moderating effects of BMI on the relationship between NT-proBNP and CAP mortality were examined using interaction terms in a multivariable regression model. The ability of NT-proBNP to predict mortality was evaluated using the area under the curve (AUC).

RESULTS

A significant inverse relationship was observed between BMI and NT-proBNP. After multivariable adjustment including BMI, NT-proBNP remained a significant predictor of CAP mortality. The AUC of the fully adjusted (including BMI) NT-proBNP model was significantly higher than that excluding BMI (p = 0.021) and that of PSI (p = 0.038), respectively. The predictive performance of NT-proBNP for mortality significantly differed by BMI group, with the NT-proBNP of the overweight and obesity group having a significantly higher AUC than that of the underweight and normal-weight group. The AUC of NT-proBNP was significantly higher and tended to be higher than that of PSI in the overweight group (p = 0.013) and the obesity group (p = 0.113), respectively.

CONCLUSIONS

BMI significantly strengthens the prognostic performance of NT-proBNP in CAP patients. The BMI-NT-proBNP interaction is significantly associated with CAP mortality, but as a prognostic determinant for CAP, NT-proBNP seems to be more useful for overweight and obese patients than for underweight and normal-weight patients.

Clinical characteristics of community-acquired pneumonia due to Moraxella catarrhalis in adults: a retrospective single-centre study

Background

Although Moraxella catarrhalis (M. catarrhalis) is a common cause of community-acquired pneumonia (CAP), studies investigating clinical manifestations of CAP due to M. catarrhalis (MC-CAP) in adults are limited. Since S. pneumoniae is the leading cause of CAP globally, it is important to distinguish between MC-CAP and CAP due to S. pneumoniae (SP-CAP) in clinical practice. However, no past study compared clinical characteristics of MC-CAP and SP-CAP by statistical analysis. We aimed to clarify the clinical characteristics of MC-CAP by comparing those of SP-CAP, as well as the utility of sputum Gram staining.

Methods

This retrospective study screened CAP patients aged over 20 years visiting or admitted to Okinawa Miyako Hospital between May 2013 and April 2018. Among these, we included patients whom either M. catarrhalis alone or S. pneumoniae alone was isolated from their sputum by bacterial cultures.

Results

We identified 134 MC-CAP and 130 SP-CAP patients. Although seasonality was not observed in SP-CAP, almost half of MC-CAP patients were admitted in the winter. Compared to those with SP-CAP, MC-CAP patients were older (p < 0.01) and more likely to have underlying pulmonary diseases such as asthma and bronchiectasis (p < 0.01). Approximately half of asthmatic MC-CAP and SP-CAP patients had asthma attacks. Although winter is an influenza season in Japan, co-infection with influenza virus was less common in MC-CAP compared to SP-CAP patients (3% vs. 15%, p < 0.01). Bronchopneumonia patterns on X-ray, as well as bronchial wall thickening, bilateral distribution, and segmental pattern on CT were more common in MC-CAP patients than in SP-CAP patients (p < 0.01). Sputum Gram stain was highly useful method for the diagnosis in both MC-CAP and SP-CAP (78.4% vs. 89.2%), and penicillins were most frequently chosen as an initial treatment for both pneumonias.

Conclusions

This is the first study to show that MC-CAP occurred in older people compared to SP-CAP, influenza virus co-infection was less common in MC-CAP than SP-CAP, and that MC-CAP frequently caused asthma attacks. Gram stain contributed for the appropriate treatment, resulting in conserving broad-spectrum antibiotics such as cephalosporins and fluoroquinolones in both MC-CAP and SP-CAP patients.

Nursing Home-Associated Pneumonia, Part II: Etiology and Treatment

This is the second of 2 parts of a narrative review of nursing home-associated pneumonia (NHAP) that deals with etiology and treatment in the nursing home. In the 1980s and 1990s, the etiology of NHAP was considered to be similar to community-acquired pneumonia (CAP). This belief was reflected in CAP guidelines until 2005 when the designation healthcare-associated pneumonia or HCAP was introduced and nursing home residents were included in the HCAP category. Patients in the HCAP group were thought to be at high risk for pneumonia because of multidrug resistant organisms and required empiric broad-spectrum antibiotic therapy much like people with hospital-acquired infection. Subsequent studies of the etiology of NHAP using sophisticated diagnostic testing found limited evidence of resistant organisms such as methicillin-resistant Staphylococcus aureus or resistant gram-negative organisms or atypical organisms. In terms of management of NHAP in the nursing home there are several considerations that are discussed: hospitalization decision, initial oral or parenteral therapy, timing of switch to an oral regimen if parenteral therapy is initially prescribed, duration of therapy with an emphasis on shorter courses, and follow-up during therapy including the use of the "antibiotic time out" protocol. The oral and parenteral antibiotic regimens recommended for treatment of NHAP in this report are based on limited information because there are no randomized controlled trials to define the optimum regimen. In conclusion, most residents with pneumonia can be treated successfully in the nursing home. However, there is an urgent need for a specific NHAP diagnosis and treatment guideline that will give providers guidance in the management of this infection in the nursing home.

Effect of Nutritional Intervention Programs on Nutritional Status and Readmission Rate in Malnourished Older Adults with Pneumonia: A Randomized Control Trial

Pneumonia leads to changes in body composition and weakness due to the malnourished condition. In addition, patient family caregivers always have a lack of nutritional information, and they do not know how to manage patients’ nutritional intake during hospitalization and after discharge. Most intervention studies aim to provide nutritional support for older patients. However, whether long-term nutritional intervention by dietitians and caregivers from patients’ families exert clinical effects—particularly in malnourished pneumonia—on nutritional status and readmission rate at each interventional phase, from hospitalization to postdischarge, remains unclear. To investigate the effects of an individualized nutritional intervention program (iNIP) on nutritional status and readmission rate in older adults with pneumonia during hospitalization and three and six months after discharge. Eighty-two malnourished older adults with a primary diagnosis of pneumonia participated. Patients were randomly allocated to either a nutrition intervention (NI) group or a standard care (SC) group. Participants in the NI group received an iNIP according to energy and protein intake requirements in addition to dietary advice based on face-to-face interviews with their family caregivers during hospitalization. After discharge, phone calls were adopted for prescribing iNIPs. Anthropometry (i.e., body mass index, limb circumference, and subcutaneous fat thickness), blood parameters (i.e., albumin and total lymphocyte count), hospital stay, Mini-Nutritional Assessment-Short Form (MNA-SF) score, target daily calorie intake, total calorie intake adherence rate, and three-major-nutrient intakes were assessed during hospitalization and three and six months after discharge. Both groups received regular follow-up through phone calls. Furthermore, the rate of readmission resulting from pneumonia was recorded after discharge. During hospital stay, the NI group showed significant increases in daily calorie intake, total calorie intake adherence rate, and protein intake compared with the SC group (p < 0.05); however, no significant difference was found in anthropometry, blood biochemical values, MNA-SF scores, and hospital stay. At three and six months after discharge, the NI group showed significantly higher daily calorie intake and MNA-SF scores (8.2 vs. 6.5 scores at three months; 9.3 vs. 7.6 scores at six months) than did the SC group (p < 0.05). After adjusting for sex, the readmission rate for pneumonia significantly decreased by 77% in the NI group compared with that in the SC group (p = 0.03, OR: 0.228, 95% CI: 0.06–0.87). A six-month iNIP under dietitian and patient family nutritional support for malnourished older adults with pneumonia can significantly improve their nutritional status and reduce the readmission rate.

Lower long-term mortality in obese patients with community-acquired pneumonia: possible role of CRP

OBJECTIVE

The present study aimed to investigate the relationship between obesity and mortality in patients with community-acquired pneumonia (CAP) in China.

METHODS

In total, 909 patients with CAP were recruited for this study from January 2010 to June 2015. All patients were selected and divided into 4 groups according to their body mass index (BMI) values. All patients' clinical information was recorded. The associations among mortality; BMI; the 30-day, 6-month and 1-year survival rates for different BMI classes; the etiology of pneumonia in each BMI group; and the risk factors for 1-year mortality in CAP patients were analyzed.

RESULT

With the exception of the level of C-reactive protein (CRP), no other clinical indexes showed significant differences among the different BMI groups. No significant differences were observed among all groups in terms of the 30-d and 6-month mortality rates (p>0.05). There was a significantly lower risk of 1-year mortality in the obese group than in the nonobese group, (p<0.05). Logistic regression analysis showed that there were seven independent risk factors for 1-year mortality in CAP patients, namely, age, cardiovascular disease, cerebrovascular disease, obesity, APACHE II score, level of CRP and CAP severity.

CONCLUSION

Compared with nonobese patients with CAP, obese CAP patients may have a lower mortality rate, especially with regard to 1-year mortality, and CRP may be associated with the lower mortality rate in obese individuals than in nonobese individuals.

Characteristics and Management of Community-Acquired Pneumonia in the Era of Global Aging

Community-acquired pneumonia (CAP) can occur at any time of life, but its incidence and risk of death are linked to increasing age. CAP in the elderly is a major health problem associated with high rates of readmission, morbidity, and mortality. Since the clinical presentation of pneumonia in the elderly may be atypical, clinicians should suspect pneumonia in older patients presenting symptoms such as falls and altered mental status, fatigue, lethargy, delirium, anorexia, in order to avoid the complications associated with delayed diagnosis and therapy. Streptococcus pneumoniae remains the most frequently reported pathogen in this population. However, particular attention should be paid to patients with risk factors for multidrug resistant pathogens, because a large proportion of elderly persons present multimorbidity. Vaccination is one of the most important preventive approaches for CAP in the elderly. In addition, lifestyle-tailored interventions for different modifiable risk factors will help to reduce the risk of pneumonia in elderly persons. Surveillance of etiological pathogens may improve vaccination policies in this population.

Chemosynthetic homologues of Mycoplasma pneumoniae β-glycolipid antigens for the diagnosis of mycoplasma infectious diseases

Mycoplasma pneumoniae expresses β-glycolipids (β-GGLs) in cytoplasmic membranes, which possess a unique β(1 → 6)-linked disaccharide epitope, which has high potential in biochemical and medicinal applications. In the present study, a series of β-GGLs homologues with different acyl chains (C12, C14, C16, and C18) were prepared from a common precursor. An ELISA assay using an anti-(β-GGLs) monoclonal antibody indicated that the synthetic homologues with long acyl chains had greater diagnostic potential in the order C18 > C16 > C14 > C12. Toward a simultaneous detection of natural glycolipids by mass spectrometry (MS), a deuterium-labeled C16 homologue (β-GGL-C16-d₃) was prepared and applied as an internal standard for a high-resolution electrospray ionization MS (ESI-MS) analysis. The ESI-MS analysis was used to identify and quantify acyl homologues (C16/C16, C16/C18, and C18/C18) of β-GGL-C16 in cultured M. pneumoniae. A β-GGLs homologue with a 1,2-diacetyl group (C2) was also prepared as a "water soluble" glycolipid homologue and characterized by ¹H NMR spectroscopy. We envisage that each of these chemosynthetic homologues will provide promising approaches to solve medical and biological problems associated with mycoplasma infectious diseases (MIDs).

Diagnosis and treatment of community-acquired pneumonia in adults: 2016 clinical practice guidelines by the Chinese Thoracic Society, Chinese Medical Association

Community‐acquired pneumonia (CAP) in adults is an infectious disease with high morbidity in China and the rest of the world. With the changing pattern in the etiological profile of CAP and advances in medical techniques in diagnosis and treatment over time, Chinese Thoracic Society of Chinese Medical Association updated its CAP guideline in 2016 to address the standard management of CAP in Chinese adults. Extensive and comprehensive literature search was made to collect the data and evidence for experts to review and evaluate the level of evidence. Corresponding recommendations are provided appropriately based on the level of evidence. This updated guideline covers comprehensive topics on CAP, including aetiology, antimicrobial resistance profile, diagnosis, empirical and targeted treatments, adjunctive and supportive therapies, as well as prophylaxis. The recommendations may help clinicians manage CAP patients more effectively and efficiently. CAP in pediatric patients and immunocompromised adults is beyond the scope of this guideline. This guideline is only applicable for the immunocompetent CAP patients aged 18 years and older. The recommendations on selection of antimicrobial agents and the dosing regimens are not mandatory. The clinicians are recommended to prescribe and adjust antimicrobial therapies primarily based on their local etiological profile and results of susceptibility testing, with reference to this guideline.

Bacterial Pneumonia in Older Adults

The incidence of pneumonia increases with age, and is particularly high in patients who reside in long-term care facilities (LTCFs). Mortality rates for pneumonia in older adults are high and have not decreased in the last decade. Atypical symptoms and exacerbation of underlying illnesses should trigger clinical suspicion of pneumonia. Risk factors for multidrug-resistant organisms are more common in older adults, particularly among LTCF residents, and should be considered when making empiric treatment decisions. Monitoring of clinical stability and underlying comorbid conditions, potential drug-drug interactions, and drug-related adverse events are important factors in managing elderly patients with pneumonia.

Role of Atypical Bacteria in Hospitalized Patients With Nursing Home-Acquired Pneumonia

Background: Nursing home-acquired pneumonia (NHAP) has been identified as one of the leading causes of mortality and hospitalization for long-term care residents. However, current and previous pneumonia guidelines differ on the appropriate management of NHAP in hospitalized patients, specifically in regard to the role of atypical bacteria such as Chlamydiae pneumonia, Mycoplasma pneumoniae, and Legionella. Objectives: The purpose of this review is to evaluate clinical trials conducted in hospitalized patients with NHAP to determine the prevalence of atypical bacteria and thus the role for empiric antibiotic coverage of these pathogens in NHAP. Methods: Comprehensive MEDLINE (1966-April 2016) and Embase (1980-April 2016) searches were performed using the terms "atypical bacteria", "atypical pneumonia", "nursing-home acquired pneumonia", "pneumonia", "elderly", "nursing homes", and "long term care". Additional articles were retrieved from the review of references cited in the collected studies. Thirteen published clinical trials were identified. Results: In the majority of studies, atypical bacteria were infrequently identified in patients hospitalized with NHAP. However, when an active community-acquired pneumonia (CAP) cohort was available, the rate of atypical bacteria between NHAP and CAP study arms was similar. Only 3 studies in this review adhered to recommended strategies for investigating atypical bacteria; in 2 of these studies, C. pneumoniae was the most common pathogen identified in NHAP cohorts. Conclusion: Although atypical bacteria were uncommon in most NHAP studies in this review, suboptimal microbial investigations were commonly performed. To accurately describe the role of atypical bacteria in NHAP, more studies using validated diagnostic tests are needed.

Changes in physical function after hospitalization in patients with nursing and healthcare-associated pneumonia

To clarify the functional changes after hospitalization due to pneumonia in elderly Japanese patients, we investigated the changes in physical functioning, nutritional routes, and diet that occurred after hospitalization in patients with nursing and healthcare-associated pneumonia (NHCAP). We analyzed 405 patients with NHCAP and compared findings with 448 patients with community-acquired pneumonia (CAP). Among the NHCAP patients, 140 (34%) patients showed a decline in activities of daily living function between baseline and discharge. After hospital discharge, 149 (37%) NHCAP patients did not return to the same residence location compared with where they were living prior to hospital admission. The frequency of this outcome was significantly higher in NHCAP patients than in CAP patients (p < 0.0001). After 6 months' follow-up, of the patients who transferred to different hospitals, 41 (73%) patients with CAP had returned to their own home, but only 16 (20%) patients with NHCAP could return home (p < 0.0001). Rates of alteration of nutritional route and type of diet from oral nutrition were significantly higher in NHCAP patients compared with CAP patients (22% vs 4%, p < 0.0001). Our results demonstrated that approximately one-third of hospitalized patients with NHCAP showed a decline in physical function. In addition, approximately one-fifth of NHCAP patients had changed their route of nutrition and type of diet. Our results indicated that physicians should attach greater importance to preventative measures against NHCAP rather than relying on antibiotic therapy post-infection in the management of pneumonia in elderly patients in order to extend their healthy life expectancy.

Multimarker Prognostication for Hospitalized Patients with Community-acquired Pneumonia

OBJECTIVE

The optimal prognostic model for community-acquired pneumonia (CAP) remains unclear. In this study, we sought to identify independent predictors of 30-day mortality in patients with CAP and to determine whether adding specific prognostic factors to each of the two clinical prediction scores could improve the prognostic yield.

METHODS

This retrospective study involved 797 CAP patients who had been hospitalized at a tertiary referral center. The patients were categorized into two groups: those who survived and those who had died on or before 30 days after admission. Select clinical parameters were then compared between the two groups.

RESULTS

During the 30-day period, there were 72 deaths (9%). We constructed two models for a multivariate analysis: one was based on a high CURB-65 score (3-5) and the other on a high pneumonia severity index (PSI) class (V). In both models, a high CURB-65 score or a high PSI class, along with the presence of dyspnea, high Eastern Cooperative Oncology Group (ECOG) performance status (3-4), and a low serum albumin level, were independent predictors of 30-day mortality. In both the CURB-65-based and PSI-based models, the addition of dyspnea, high ECOG performance status, and hypoalbuminemia (<3 g/dL) enhanced the prognostic assessment, and subsequently, the c-statistics calculated with the use of three- or four- predictor combinations exceeded 0.8.

CONCLUSION

In addition to the CURB-65 or PSI, the clinical factors of dyspnea, the ECOG performance status, and serum albumin level may be independent predictors of 30-day mortality in CAP patients. When combined with the CURB-65 or PSI, these parameters provide additional evidence for predicting poor prognoses.

Pneumococcal Disease Prevention Among Adults: Strategies for the Use of Pneumococcal Vaccines

Use of the pneumococcal conjugate vaccines among children in the U.S. since 2000 has dramatically reduced pneumococcal disease burden among adults. Significant vaccine-preventable morbidity and mortality from pneumococcal infections still remains, especially among older adults. The U.S. Advisory Committee on Immunization Practices (ACIP) has recently recommended the routine use of both pneumococcal conjugate (PCV13) and polysaccharide vaccines (PPSV23) for adults ≥65 years. These recommendations were based on the remaining burden of illness among adults and the importance of non-bacteremic pneumonia prevention in light of new evidence confirming the efficacy of PCV13 to prevent pneumococcal pneumonia among older adults. This paper reviews the evidence that led ACIP to make recommendations for PCV13 and PPSV23 use among adults, and highlights potential gaps to be addressed by future studies to inform adult vaccination policy. The changing epidemiology of invasive pneumococcal disease and pneumonia should be closely monitored to evaluate the effectiveness and continued utility of the current vaccination strategy, and to identify future directions for pneumococcal disease prevention among older adults.

Nutritional parameters affecting severity of pneumonia and length of hospital stay in patients with pneumococcal pneumonia: a retrospective cross-sectional study

Background

Pneumococcal pneumonia is the most common form of community-acquired pneumonia (CAP). Although a pneumococcal conjugate vaccine has contributed to a reduction in the incidence of pneumococcal pneumonia among older children and adults, no significant decrease in the incidence has been observed among persons aged ≥65 years. A low body mass index and hypoalbuminemia are common in Japanese patients with CAP, but the association of other nutritional parameters with the severity of pneumonia or length of hospital stay in patients with pneumococcal pneumonia is unclear.

Methods

Fifty-seven previously healthy inpatients who presented with pneumococcal pneumonia were divided into two groups: those aged ≥65 years (n = 36) and those aged <65 years (n = 21). Patients’ characteristics (the Confusion, Urea, Respiratory rate, Blood pressure, age >65 years (CURB-65) score), the pneumonia severity index (PSI), and inflammatory and metabolic nutritional parameters were compared between the two groups.

Results

The older group showed significantly lower serum albumin and cholinesterase (ChE) levels. Multivariate linear regression analysis revealed that the PSI was positively correlated with age in both groups. In the younger age group, both the CURB-65 score and PSI showed significant negative correlations with the serum ChE level, and there was a significant negative correlation between the length of stay and serum total cholesterol (T-cho) level. In the older group, the fasting period, lymphocyte count, and age showed significant positive correlations with the length of stay. There was a significant negative correlation between the length of stay and serum albumin level, but no correlation with the serum ChE or T-cho levels, in the older patients.

Conclusions

Our findings suggest that in patients aged <65 years, age and serum ChE and T-cho levels were associated with both the severity of pneumococcal pneumonia and length of stay. In contrast, the length of stay in older patients was associated with multiple factors that differed from those in younger patients. These differences may reflect age-related immunosenescence in older patients and a greater effect of serum ChE and T-cho levels on immunity in younger patients.

Pneumococcal disease prevention among adults: Strategies for the use of pneumococcal vaccines

Use of the pneumococcal conjugate vaccines among children in the US since 2000 has dramatically reduced pneumococcal disease burden among adults. Significant vaccine-preventable morbidity and mortality from pneumococcal infections still remains, especially among older adults. The US Advisory Committee on Immunization Practices (ACIP) has recently recommended the routine use of both pneumococcal conjugate (PCV13) and polysaccharide vaccines (PPSV23) for adults ≥65 years. These recommendations were based on the remaining burden of illness among adults and the importance of non-bacteremic pneumonia prevention in light of new evidence confirming the efficacy of PCV13 to prevent pneumococcal pneumonia among older adults. This paper reviews the evidence that led the ACIP to make recommendations for PCV13 and PPSV23 use among adults, and highlights potential gaps to be addressed by future studies to inform adult vaccination policy. The changing epidemiology of invasive pneumococcal disease and pneumonia should be closely monitored to evaluate the effectiveness and continued utility of the current vaccination strategy, and to identify future directions for pneumococcal disease prevention among older adults.

Update on the pathogenesis and management of pneumonia in the elderly-roles of aspiration pneumonia

Pneumonia in the elderly results in the highest mortality among cases of community-acquired pneumonia (CAP). The pathophysiology of pneumonia in the elderly is primarily due to aspiration pneumonia (ASP). ASP comprises two pathological conditions: airspace infiltration with bacterial pathogens and dysphagia-associated miss-swallowing. The first-line therapy for the treatment of bacterial pneumonia in the elderly is a narrow spectrum of antibiotics, including sulbactam/ampicillin, which are effective against major lower respiratory infection pathogens and anaerobes. The bacterial pathogens of ASP cases of pneumonia in the elderly are similar to those associated with adult CAP. In addition to an appropriate course of antibiotics, pharmacologic and non-pharmacologic approaches for dysphagia and upper airway management are necessary for the treatment and prevention of pneumonia. Swallowing rehabilitation, oral health care, pneumococcal vaccination, gastroesophageal reflux management, and a head-up position during the night are necessary for the treatment and prevention of repeated episodes of pneumonia in elderly patients. In addition, tuberculosis should always be considered for the differential diagnosis of pneumonia in this patient population.

Multiple logistic regression analysis of risk factors in elderly pneumonia patients: QTc interval prolongation as a prognostic factor

Background

Acute pneumonia is a serious problem in the elderly and various risk factors have already been reported, but the involvement of QTc interval prolongation remains uncertain. The aim of this study was to elucidate the prognostic factors for the development of pneumonia in elderly patients and to study the possible involvement of QTc interval prolongation.

Methods

The subjects were 249 hospitalized pneumonia patients more than 65 years old in Aki-Ohta Hospital from January 2010 to December 2013. Community-acquired pneumonia patients and nursing care and healthcare-associated pneumonia patients were included in the study. The pneumonia severity index, vital signs, blood chemistry data and ECG findings were retrospectively compared using multiple logistic regression analysis.

Results

39 patients died within 30 days from onset. The clinical features related to poor prognosis were: advanced age, past history of cerebral vascular disease and/or diabetes mellitus, decreased serum albumin level, higher CURB-65 or PORT index scores and QTc interval prolongation. Patients showing a prolonged QTc interval had a higher mortality than those with a normal QTc interval. A prolonged QTc interval was not related to serum calcium concentration and/or treatment with QTc prolongation drug, clarithromycin or azithromycin, but related to age, lower albumin concentration and past history of diabetes mellitus.

Conclusions

These findings suggest potential prognostic factors for pneumonia in elderly patients, including a prolonged QTc interval (> 0.44 seconds).

Nursing home-acquired pneumonia: course and management in the emergency department

Background

Pneumonia is among the foremost causes of hospitalization and mortality in patients residing in extended care facilities. Despite its prevalence, there is currently little literature focusing on the course and management of nursing home-acquired pneumonia (NHAP) in the emergency department (ED). Our objective was to investigate the ED presentation, course, management and outcomes in patients admitted through the ED with NHAP.

Methods

A retrospective chart review of nursing home patients with a presumptive or final diagnosis of pneumonia admitted through the ED was performed at two large hospitals in Detroit, Michigan.

Results

A total of 296 patients were included in the study from 2002 to 2007 with a mean age of 81.1 years (SD ± 10.95) and 55.4% females. Blood cultures were performed on 90.8% of patients in the ED; 17.8% of these revealed growths, but half of these were considered contaminants. Initial chest x-ray in the ED was read as possible pneumonia in 18.2% of patients; 73.9% were started on antibiotics (ABX) in the ED. Mean hospital length of stay (LOS) was 10.75 days (SD ± 9.35) and in-hospital mortality was 16.2%. Time until first ABX in univariate analysis was nearly significant (p = 0.053) for mortality prediction, and the appropriate versus inappropriate ABX (per the Infectious Diseases Society of America and American Thoracic Society guidelines) did not affect mortality. Patients treated with a single ABX had significantly increased LOS (p = 0.0089). There was poor correlation between LOS and time until first ABX as well as LOS and time until appropriate ABX with a correlation coefficient of -0.048 (p = 0.42) and -0.08 (p = 0.43), respectively.

Conclusions

In this data set of NHAP patients admitted through the ED, we found a surprisingly low prevalence of true-positive blood cultures, high incidence of antibiotic pre-treatment at nursing homes prior to admission, high hospital mortality and low immunization rates. There was a wide spectrum of pathogens grown in blood culture. Only two thirds of the patients had dyspnea at presentation, and less than half had either cough or fever. On physical examination, about one fourth had no clinical findings consistent with pneumonia. Further, less than one fifth of chest x-rays were interpreted as possible pneumonia.

Importance of functional assessment in the management of community-acquired and healthcare-associated pneumonia

OBJECTIVE

In Japan, the number of elderly people who have difficulties performing the activities of daily living (ADLs) is increasing. The objective of this study was to assess the relationship between ADL and the clinical characteristics of pneumonia.

METHODS

We conducted a retrospective study of 219 adult patients hospitalized due to pneumonia [151 patients with community-acquired pneumonia (CAP) and 68 patients with healthcare-associated pneumonia (HCAP)]. CAP, HCAP, and all the patients were stratified into two groups using a modified version of the Katz index of five ADLs as follows: independent in all ADLs or dependent in one to three ADLs (CAP-A, HCAP-A, and All-A groups) and dependent in four or five ADLs (CAP-B, HCAP-B, and All-B groups). Disease severity, microbiological findings, and mortality were compared between the groups.

RESULTS

As the ability to perform ADLs declined, A-DROP scores (the CAP severity measurement index) increased significantly in CAP (CAP-A: 1.1±1.1, CAP-B: 2.6±1.1), HCAP (HCAP-A: 2.0±1.0, HCAP-B: 2.8±1.0), and all patients (All-A: 1.3±1.1, All-B: 2.8±1.0). Thirty-day mortality was higher in the CAP-B (23.1%) and All-B (19.2%) groups than in the CAP-A (0.7%) and All-A (1.8%) groups, respectively. A multivariate Cox proportional hazards analysis showed an ADL score ≥ four to be a significant predictor of 30-day mortality in CAP patients [hazard ratio (HR), 19.057; 95% confidence interval (CI), 1.930-188.130] and in all patients (HR, 8.180; 95% CI, 1.998-33.494).

CONCLUSION

A functional assessment using a modified version of the Katz index is useful for the management of CAP and HCAP patients.

Retrospective analysis of nursing and healthcare-associated pneumonia: analysis of adverse prognostic factors and validity of the selection criteria

BACKGROUND

Nursing and healthcare-associated pneumonia (NHCAP) is a relatively new condition that was recently defined by the Japanese Respiratory Society. Previous reports and guidelines have not thoroughly investigated the adverse prognostic factors and validity of the selection criteria for NHCAP. The purpose of this research was to clarify the adverse prognostic factors of NHCAP and investigate the validity of the selection criteria with respect to patient deaths.

METHODS

We retrospectively analyzed 418 patients with pneumonia who were admitted to our hospital between January 2009 and December 2011.

RESULTS

We analyzed 215 (51.4%) cases of community-acquired pneumonia (CAP) and 203 (48.6%) cases of NHCAP. NHCAP patients were generally older and had poorer performance status (PS), more complications, and higher levels of mortality than CAP patients. In both groups, the most common causative pathogen was Streptococcus pneumoniae. A multivariate analysis of NHCAP revealed that age ≥ 80 years, oxygen saturation (SpO2) ≤ 90%, and methicillin-resistant Staphylococcus aureus (MRSA) infection to be independent factors associated with mortality. Of the NHCAP selection criteria, a PS ≥ 3 and a hospitalization history within the past 90 days were adverse prognostic factors in the broad community-acquired pneumonia category (CAP+NHCAP), according to a multivariate analysis. Univariate analysis revealed that admission to an extended care facility or nursing home was associated with death.

CONCLUSIONS

Our results demonstrated that age ≥ 80 years, SpO2 ≤ 90%, and MRSA infection were adverse prognostic factors for NHCAP patients. Furthermore, we confirmed the validity of the NHCAP selection criteria.

A new strategy for healthcare-associated pneumonia: a 2-year prospective multicenter cohort study using risk factors for multidrug-resistant pathogens to select initial empiric therapy

BACKGROUND

Optimal empiric therapy for hospitalized patients with healthcare-associated pneumonia (HCAP) is uncertain.

METHODS

We prospectively applied a therapeutic algorithm, based on the presence of risk factors for multidrug-resistant (MDR) pathogens in a multicenter cohort study of 445 pneumonia patients, including both community-acquired pneumonia (CAP; n = 124) and HCAP (n = 321).

RESULTS

MDR pathogens were more common (15.3% vs 0.8%, P < .001) in HCAP patients than in CAP patients, including Staphylococcus aureus (11.5% vs 0.8%, P < .001); methicillin-resistant S. aureus (6.9% vs 0%, P = .003); Enterobacteriaceae (7.8% vs 2.4%, P = .037); and Pseudomonas aeruginosa (6.9% vs 0.8%, P = .01). Using the proposed algorithm, HCAP patients with ≥2 MDR risk factors, one of which was severity of illness (n = 170), vs HCAP patients with 0-1 risk factor (n = 151) had a significantly higher frequency of MDR pathogens (27.1% vs 2%, P < .001). In total, 93.1% of HCAP patients were treated according to the therapy algorithm, with only 53% receiving broad-spectrum empiric therapy, yet 92.9% received appropriate therapy for the identified pathogen. Thirty-day mortality was significantly higher for HCAP than for CAP (13.7% vs 5.6%, P = .017), but among HCAP patients with 0-1 MDR risk factor, mortality was lower than with ≥2 MDR risk factors (8.6% vs 18.2%, P = .012). In multivariate analysis, initial treatment failure, but not inappropriate empiric antibiotic therapy, was a mortality risk factor (odds ratio, 72.0).

CONCLUSIONS

Basing empiric HCAP therapy on its severity and the presence of risk factors for MDR pathogens is a potentially useful approach that achieves good outcomes without excessive use of broad-spectrum antibiotic therapy.

CLINICAL TRIALS REGISTRATION

Japan Medical Association Center for Clinical Trials, JMA-IIA00054.

Aging, diabetes, and hypertension are associated with decreased nasal mucociliary clearance

BACKGROUND

We showed previously that nasal mucociliary clearance was decreased in critically ill elderly subjects, most of whom had diabetes mellitus (DM) and/or hypertension (HTN). To determine if these changes were due to the effects of aging, disease, or critical illness, we studied nasal mucociliary clearance and mucus properties in an ambulatory population consisting of young, elderly, and healthy subjects and those with DM, HTN, or both.

METHODS

Of 440 subjects contacted, 252 entered the study. The subjects were divided into the following groups: (1) healthy (n 5 79, 18-94 years, 50 men) and (2) DM and/or HTN, of which 37 had DM (14-90 years, 12 men), 52 had HTN (23-90 years, 12 men), and 84 had both DM and HTN (25-82 years, 33 men). Subjects were also grouped by age: , 40 years, 40 to 59 years, and 60 years. We assessed demographic and clinical data, quality of life using the 36-Item Short Form Health Survey (SF-36) questionnaire, nasal mucociliary clearance using the saccharine transit test (STT), and in vitro mucus properties by examining the sneeze (high airflow) clearability and contact angle. A logistic regression analysis for prolonged STT . 12 min was used, and we controlled for age, sex, and diseases.

RESULTS

Subjects aged . 60 years reported a decreased SF-36 physical component relative to other age groups. Sex, BMI, BP, heart rate, pulse oximetry, blood glucose level, and mucus properties were not associated with prolonged STT. Aging and DM and/or HTN independently increased the risk of prolonged STT.

CONCLUSIONS

Aging and DM, HTN, or both diseases are independently associated with decreased nasal mucociliary clearance. This may predispose toward respiratory infections.

Global and regional mortality from 235 causes of death for 20 age groups in 1990 and 2010: a systematic analysis for the Global Burden of Disease Study 2010

BACKGROUND

Reliable and timely information on the leading causes of death in populations, and how these are changing, is a crucial input into health policy debates. In the Global Burden of Diseases, Injuries, and Risk Factors Study 2010 (GBD 2010), we aimed to estimate annual deaths for the world and 21 regions between 1980 and 2010 for 235 causes, with uncertainty intervals (UIs), separately by age and sex.

METHODS

We attempted to identify all available data on causes of death for 187 countries from 1980 to 2010 from vital registration, verbal autopsy, mortality surveillance, censuses, surveys, hospitals, police records, and mortuaries. We assessed data quality for completeness, diagnostic accuracy, missing data, stochastic variations, and probable causes of death. We applied six different modelling strategies to estimate cause-specific mortality trends depending on the strength of the data. For 133 causes and three special aggregates we used the Cause of Death Ensemble model (CODEm) approach, which uses four families of statistical models testing a large set of different models using different permutations of covariates. Model ensembles were developed from these component models. We assessed model performance with rigorous out-of-sample testing of prediction error and the validity of 95% UIs. For 13 causes with low observed numbers of deaths, we developed negative binomial models with plausible covariates. For 27 causes for which death is rare, we modelled the higher level cause in the cause hierarchy of the GBD 2010 and then allocated deaths across component causes proportionately, estimated from all available data in the database. For selected causes (African trypanosomiasis, congenital syphilis, whooping cough, measles, typhoid and parathyroid, leishmaniasis, acute hepatitis E, and HIV/AIDS), we used natural history models based on information on incidence, prevalence, and case-fatality. We separately estimated cause fractions by aetiology for diarrhoea, lower respiratory infections, and meningitis, as well as disaggregations by subcause for chronic kidney disease, maternal disorders, cirrhosis, and liver cancer. For deaths due to collective violence and natural disasters, we used mortality shock regressions. For every cause, we estimated 95% UIs that captured both parameter estimation uncertainty and uncertainty due to model specification where CODEm was used. We constrained cause-specific fractions within every age-sex group to sum to total mortality based on draws from the uncertainty distributions.

FINDINGS

In 2010, there were 52·8 million deaths globally. At the most aggregate level, communicable, maternal, neonatal, and nutritional causes were 24·9% of deaths worldwide in 2010, down from 15·9 million (34·1%) of 46·5 million in 1990. This decrease was largely due to decreases in mortality from diarrhoeal disease (from 2·5 to 1·4 million), lower respiratory infections (from 3·4 to 2·8 million), neonatal disorders (from 3·1 to 2·2 million), measles (from 0·63 to 0·13 million), and tetanus (from 0·27 to 0·06 million). Deaths from HIV/AIDS increased from 0·30 million in 1990 to 1·5 million in 2010, reaching a peak of 1·7 million in 2006. Malaria mortality also rose by an estimated 19·9% since 1990 to 1·17 million deaths in 2010. Tuberculosis killed 1·2 million people in 2010. Deaths from non-communicable diseases rose by just under 8 million between 1990 and 2010, accounting for two of every three deaths (34·5 million) worldwide by 2010. 8 million people died from cancer in 2010, 38% more than two decades ago; of these, 1·5 million (19%) were from trachea, bronchus, and lung cancer. Ischaemic heart disease and stroke collectively killed 12·9 million people in 2010, or one in four deaths worldwide, compared with one in five in 1990; 1·3 million deaths were due to diabetes, twice as many as in 1990. The fraction of global deaths due to injuries (5·1 million deaths) was marginally higher in 2010 (9·6%) compared with two decades earlier (8·8%). This was driven by a 46% rise in deaths worldwide due to road traffic accidents (1·3 million in 2010) and a rise in deaths from falls. Ischaemic heart disease, stroke, chronic obstructive pulmonary disease (COPD), lower respiratory infections, lung cancer, and HIV/AIDS were the leading causes of death in 2010. Ischaemic heart disease, lower respiratory infections, stroke, diarrhoeal disease, malaria, and HIV/AIDS were the leading causes of years of life lost due to premature mortality (YLLs) in 2010, similar to what was estimated for 1990, except for HIV/AIDS and preterm birth complications. YLLs from lower respiratory infections and diarrhoea decreased by 45-54% since 1990; ischaemic heart disease and stroke YLLs increased by 17-28%. Regional variations in leading causes of death were substantial. Communicable, maternal, neonatal, and nutritional causes still accounted for 76% of premature mortality in sub-Saharan Africa in 2010. Age standardised death rates from some key disorders rose (HIV/AIDS, Alzheimer's disease, diabetes mellitus, and chronic kidney disease in particular), but for most diseases, death rates fell in the past two decades; including major vascular diseases, COPD, most forms of cancer, liver cirrhosis, and maternal disorders. For other conditions, notably malaria, prostate cancer, and injuries, little change was noted.

INTERPRETATION

Population growth, increased average age of the world's population, and largely decreasing age-specific, sex-specific, and cause-specific death rates combine to drive a broad shift from communicable, maternal, neonatal, and nutritional causes towards non-communicable diseases. Nevertheless, communicable, maternal, neonatal, and nutritional causes remain the dominant causes of YLLs in sub-Saharan Africa. Overlaid on this general pattern of the epidemiological transition, marked regional variation exists in many causes, such as interpersonal violence, suicide, liver cancer, diabetes, cirrhosis, Chagas disease, African trypanosomiasis, melanoma, and others. Regional heterogeneity highlights the importance of sound epidemiological assessments of the causes of death on a regular basis.

FUNDING

Bill & Melinda Gates Foundation.

Streptococcus pneumoniae in biofilms are unable to cause invasive disease due to altered virulence determinant production

It is unclear whether Streptococcus pneumoniae in biofilms are virulent and contribute to development of invasive pneumococcal disease (IPD). Using electron microscopy we confirmed the development of mature pneumococcal biofilms in a continuous-flow-through line model and determined that biofilm formation occurred in discrete stages with mature biofilms composed primarily of dead pneumococci. Challenge of mice with equal colony forming units of biofilm and planktonic pneumococci determined that biofilm bacteria were highly attenuated for invasive disease but not nasopharyngeal colonization. Biofilm pneumococci of numerous serotypes were hyper-adhesive and bound to A549 type II pneumocytes and Detroit 562 pharyngeal epithelial cells at levels 2 to 11-fold greater than planktonic counterparts. Using genomic microarrays we examined the pneumococcal transcriptome and determined that during biofilm formation S. pneumoniae down-regulated genes involved in protein synthesis, energy production, metabolism, capsular polysaccharide (CPS) production, and virulence. We confirmed these changes by measuring CPS by ELISA and immunoblotting for the toxin pneumolysin and the bacterial adhesins phosphorylcholine (ChoP), choline-binding protein A (CbpA), and Pneumococcal serine-rich repeat protein (PsrP). We conclude that biofilm pneumococci were avirulent due to reduced CPS and pneumolysin production along with increased ChoP, which is known to bind C-reactive protein and is opsonizing. Likewise, biofilm pneumococci were hyper-adhesive due to selection for the transparent phase variant, reduced CPS, and enhanced production of PsrP, CbpA, and ChoP. These studies suggest that biofilms do not directly contribute to development of IPD and may instead confer a quiescent mode of growth during colonization.

Biofilm and planktonic pneumococci demonstrate disparate immunoreactivity to human convalescent sera

Background

Streptococcus pneumoniae (the pneumococcus) is the leading cause of otitis media, community-acquired pneumonia (CAP), sepsis, and meningitis. It is now evident that S. pneumoniae forms biofilms during nasopharyngeal colonization; the former which facilitates persistence, the latter, a prerequisite for subsequent development of invasive disease. Proteomic evaluation of S. pneumoniae suggests the antigen profile available for host-recognition is altered as a consequence of biofilm growth. This has potentially meaningful implications in regards to adaptive immunity and protection from disseminated disease. We therefore examined the antigen profile of biofilm and planktonic pneumococcal cell lysates, tested their reactivity with human convalescent sera and that generated against biofilm pneumococci, and examined whether immunization with biofilm pneumococci protected mice against infectious challenge.

Results

Biofilm pneumococci have dramatically altered protein profiles versus their planktonic counterparts. During invasive disease the humoral immune response is skewed towards the planktonic protein profile. Immunization with biofilm bacteria does not elicit a strong-cross-reactive humoral response against planktonic bacteria nor confer resistance against challenge with a virulent isolate from another serotype. We identified numerous proteins, including Pneumococcal serine-rich repeat protein (PsrP), which may serve as a protective antigens against both colonization and invasive disease.

Conclusion

Differential protein production by planktonic and biofilm pneumococci provides a potential explanation for why individuals remain susceptible to invasive disease despite previous colonization events. These findings also strongly suggest that differential protein production during colonization and disease be considered during the selection of antigens for any future protein vaccine.

Nursing home acquired pneumonia: approach to management

PURPOSE OF REVIEW

Pneumonia is among the leading causes of mortality in nursing home residents and a primary reason for transfer to acute care facilities. Compared with community-dwelling individuals, residents of long-term care facilities have extensive underlying medical illnesses and more functional disabilities and are at increased risk of acquiring drug-resistant pathogens. This review focuses on recent recommendations for diagnostic work up, validity of prognostic models, and current approach to treatment of nursing home acquired pneumonia (NHAP).

RECENT FINDINGS

The inconsistency in defining NHAP is considered a potential hindrance for a uniform approach to the management of pneumonia. Diagnostic evaluation varies between facilities and depends on severity of illness and access to laboratory facilities. The role of prognostic models in stratifying severity of disease remains largely unknown due to paucity of studies and lack of a specific scoring system for hospitalized patients with NHAP. A controversy still exists concerning the best therapeutic option for NHAP, but it is reasonable to believe that each setting is adapting the existing evidence according to the best local practice.

SUMMARY

A unified approach to defining, assessing, and stratifying pneumonia is essential to decrease morbidity and mortality in nursing home residents. High-quality randomized, controlled trials examining empiric antibiotic therapy are needed.

Susceptibility of the aging lung to environmental injury

With an ever-increasing number of elderly individuals in the world, a better understanding of the issues associated with aging and the environment is needed. The respiratory system is one of the primary interfaces between the body and the external environment. An expanding number of studies suggest that the aging pulmonary system (>65 years) is at increased risk for adverse health effects from environmental insult, such as by air pollutants, infection, and climate change. However, the mechanism(s) for increased susceptibility in this subpopulation are not well understood. In this review, we provide a limited but comprehensive overview of how the lung ages, examples of environmental exposures associated with injury to the aging lung, and potential mechanisms underlying the increased vulnerability of the aging lung to injury from environmental factors.

The pneumococcal serine-rich repeat protein is an intra-species bacterial adhesin that promotes bacterial aggregation in vivo and in biofilms

The Pneumococcal serine-rich repeat protein (PsrP) is a pathogenicity island encoded adhesin that has been positively correlated with the ability of Streptococcus pneumoniae to cause invasive disease. Previous studies have shown that PsrP mediates bacterial attachment to Keratin 10 (K10) on the surface of lung cells through amino acids 273–341 located in the Basic Region (BR) domain. In this study we determined that the BR domain of PsrP also mediates an intra-species interaction that promotes the formation of large bacterial aggregates in the nasopharynx and lungs of infected mice as well as in continuous flow-through models of mature biofilms. Using numerous methods, including complementation of mutants with BR domain deficient constructs, fluorescent microscopy with Cy3-labeled recombinant (r)BR, Far Western blotting of bacterial lysates, co-immunoprecipitation with rBR, and growth of biofilms in the presence of antibodies and competitive peptides, we determined that the BR domain, in particular amino acids 122–166 of PsrP, promoted bacterial aggregation and that antibodies against the BR domain were neutralizing. Using similar methodologies, we also determined that SraP and GspB, the Serine-rich repeat proteins (SRRPs) of Staphylococcus aureus and Streptococcus gordonii, respectively, also promoted bacterial aggregation and that their Non-repeat domains bound to their respective SRRPs. This is the first report to show the presence of biofilm-like structures in the lungs of animals infected with S. pneumoniae and show that SRRPs have dual roles as host and bacterial adhesins. These studies suggest that recombinant Non-repeat domains of SRRPs (i.e. BR for S. pneumoniae) may be useful as vaccine antigens to protect against Gram-positive bacteria that cause infection.

Serine-rich repeat proteins (SRRPs) are a family of surface-expressed proteins found in numerous Gram-positive pathogens, including Staphylococcus aureus, Streptococcus pneumoniae, Group B streptococci, and the oral streptococci that cause infective endocarditis. For all of these bacteria, SRRPs have been demonstrated to play pivotal roles in adhesion to tissues and the development of invasive disease. It is now known that biofilm formation is an important step for bacterial pathogenesis. Bacteria in biofilms have been shown to have differences in metabolism, gene expression, and protein production that contribute to enhanced surface adhesion and the persistence of an infection. Herein we describe a novel role for PsrP, the S. pneumoniae SRRP, as an intra-species bacterial adhesin that promotes bacterial aggregation in the lungs of infected mice during pneumonia. In vitro we show that the Basic Region domain of PsrP promotes self-interactions that result in denser biofilms, greater biofilm biomass, and altered architectures of surface grown cultures; these interactions could be neutralized by antibodies to PsrP that are protective against pneumococcal infection. We also demonstrate that the SRRPs of S. aureus and Streptococcus gordonii also function as intra-species bacterial adhesins. Therefore we conclude that SRRPs have dual roles as host-cell and intra-species bacterial adhesins.