Pneumonia presenting with organ dysfunctions: Causative microorganisms, host factors and outcome

Clinical impact of transient lymphopenia

Transient or persistent immunosuppression is a known risk factor for morbidity and mortality in critically ill patients. Aim of the present study is to evaluate the lymphopenia in patients admitted to the Emergency Unit of AOU Policlinico Umberto I, to investigate its prevalence at admission and the persistence during hospitalization until discharge. Possible correlations were evaluated between lymphopenia, diagnosis of admission, comorbidities and chronic treatments. In this study, 240 patients (142 men; 98 female; mean age 75.1 ± 15.1) were enrolled. Patients were divided into two groups according to the lymphocytes count at hospital admission, namely "Group A" with lymphopenia and "Group B" with values in the normal range. Moreover, the patients in group A were distinguished in relation to the regression or persistence of the lymphopenia assessed at the time of hospital discharge (Group A1: persistence; Group A2: normalization). Prevalence of lymphopenia at admission was 57%; Group A showed higher mean age and percentage of patients over 65 years of age; and none differences were observed regarding gender. Prevalence of lymphopenia at admission was 57%; Group A showed higher mean age and percentage of patients over 65 years of age; no differences were observed regarding gender. All subsets of the lymphocytes (CD4+, CD8+, NK) were equally reduced. Persistent lymphopenia was found in 19% of patients. Lymphopenia should be valued at the time of hospital admission as a factor influencing the prognosis, the management and the treatment of these patients.

Pneumonia Update for Emergency Clinicians

Purpose of Review

Many new concepts in diagnosis, management, and risk stratification of patients with pneumonia have been described recently. The COVID pandemic made importance of viruses as dangerous pathogens of pneumonia quite clear while several non-invasive measures for patients with respiratory failure gained a more wide-spread usage.

Recent Findings

Studies continue to examine feasibility of bedside ultrasound as a tool in accurate diagnosis of pneumonia in the emergency department, and several new antibiotics have been approved for treatment while others are in late-stage clinical trials. Additionally, the Infectious Diseases Society, American Thoracic Society, and their European counterparts published updated guidelines in recent years. For differences important to emergency medicine clinicians and new emphasis as compared to the prior guidelines, please see Table 1. Several new antibiotics have been approved recently but remain relatively unknown to emergency clinicians as their use is frequently restricted to infectious disease specialists.Table 1

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.

[Management of Adult Community-Acquired Pneumonia and Prevention - Update 2021 - Guideline of the German Respiratory Society (DGP), the Paul-Ehrlich-Society for Chemotherapy (PEG), the German Society for Infectious Diseases (DGI), the German Society of Medical Intensive Care and Emergency Medicine (DGIIN), the German Viological Society (DGV), the Competence Network CAPNETZ, the German College of General Practitioneers and Family Physicians (DEGAM), the German Society for Geriatric Medicine (DGG), the German Palliative Society (DGP), the Austrian Society of Pneumology Society (ÖGP), the Austrian Society for Infectious and Tropical Diseases (ÖGIT), the Swiss Respiratory Society (SGP) and the Swiss Society for Infectious Diseases Society (SSI)]

The present guideline provides a new and updated concept of the management of adult patients with community-acquired pneumonia. It replaces the previous guideline dating from 2016.The guideline was worked out and agreed on following the standards of methodology of a S3-guideline. This includes a systematic literature search and grading, a structured discussion of recommendations supported by the literature as well as the declaration and assessment of potential conflicts of interests.The guideline has a focus on specific clinical circumstances, an update on severity assessment, and includes recommendations for an individualized selection of antimicrobial treatment.The recommendations aim at the same time at a structured assessment of risk for adverse outcome as well as an early determination of treatment goals in order to reduce mortality in patients with curative treatment goal and to provide palliation for patients with treatment restrictions.

Community-acquired bacterial pneumonia in adults: An update

Community-acquired pneumonia (CAP) is the prominent cause of mortality and morbidity with important clinical impact across the globe. India accounts for 23 per cent of global pneumonia burden with case fatality rates between 14 and 30 per cent, and Streptococcus pneumoniae is considered a major bacterial aetiology. Emerging pathogens like Burkholderia pseudomallei is increasingly recognized as an important cause of CAP in Southeast Asian countries. Initial management in the primary care depends on clinical assessment while the hospitalized patients require combinations of clinical scores, chest radiography and various microbiological and biomarker assays. This comprehensive diagnostic approach together with additional sampling and molecular tests in selected high-risk patients should be practiced. Inappropriate therapy in CAP in hospitalized patients lengthens hospital stay and increases cost and mortality. In addition, emergence of multidrug-resistant organisms poses tough challenges in deciding empirical as well as definitive therapy. Developing local evidence on the cause and management should be a priority to improve health outcomes in CAP.

Modified PIRO (predisposition, insult, response, organ dysfunction) severity score as a predictor for mortality of children with pneumonia in Hasan Sadikin Hospital, Bandung, Indonesia

Background

Clinical manifestations for pneumonia vary from mild to severe. The PIRO model (predisposition, insult, response, organ dysfunction) was used as scoring system to determine severity of sepsis and pneumonia in adult patients. The PIRO model was modified for sorting the severity of pneumonia in children and predicting its risk of mortality.

Methods

An ambispective cohort study of pneumonia patients aged 1 month to ≤ 18 years admitted over the period from May to September 2020. Data were collected from history, physical examination, laboratory examination, and chest radiography. Based on bivariate analysis (p<0.05 and relative risk (RR) with 95% confidence interval), variables of each PIRO component that were significant for mortality were assigned a value of 1. The cut-off score for predictor of mortality was calculated using the receiver operating characteristics (ROC) curve and the scores were stratified into three degrees of risk based on interquartile range, score ≤Q1 was categorized as low risk; Q1-Q3 was categorized as moderate risk; and score >Q3 was categorized as high risk.

Results

Out of the 80 subjects enrolled, 6 months-5 years was the largest age group (56.3%). The observed mortality was 15/80 (18.8%). The modified PIRO severity score was compiled from significant variables of predisposition (malnutrition), insult (chest radiograph), response (hypoxemia, hypotension, CRP >0.5 mg/dL, PCT >0.5 ng/dL) and organ dysfunction, with range of score 0-7. Score >3 was categorized as a cut-off point score for predictor of mortality with AUC 0.919 (95% CI 0.836–0.968), sensitivity of 80%, and specificity of 84.62%. Subjects with score >3 have RR of 10.544 compared to those with score ≤3. The stratification of score level was low (≤2), moderate (3-4), and high (5-7). The mortality levels were 0%, 46.7%, and 53.3%, respectively.

Conclusions

Modified PIRO severity score can be used as a sorting tool and predictor of mortality risk in children with pneumonia. This score can also be used to select candidates for intensive care, especially in health facilities with limited intensive care capacity.

Role of the inflammatory response in community-acquired pneumonia: clinical implications

INTRODUCTION

Despite adequate antibiotic coverage, community-acquired pneumonia (CAP) remains a leading cause of hospitalization and mortality worldwide. It induces both a local pulmonary and a systemic inflammatory response, particularly significant in severe cases. The intensity of the dysregulated host response varies from patient to patient and has a negative impact on survival and other outcomes.

AREAS COVERED

This comprehensive review summarizes the pathophysiological aspects of the inflammatory response in CAP, briefly discusses the usefulness of biomarkers, and assesses the clinical evidence for modulating the inflammatory pathways. We searched PubMed for the most relevant studies, reviews, and meta-analysis until August 2020.

EXPERT OPINION

Notable efforts have been made to identify biomarkers that can accurately differentiate between viral and bacterial etiology, and indeed, to enhance risk stratification in CAP. However, none has proven ideal and no recommended biomarker-guided algorithms exist. Biomarker signatures from proteomic and metabolomic studies could be more useful for such assessments. To date, most studies have produced contradictory results concerning the role of immunomodulatory agents (e.g. corticosteroids, macrolides, and statins) in CAP. Adequately identifying the population who may benefit most from effective modulation of the inflammatory response remains a challenge.

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.

Influenza and Bacterial Coinfection in Adults With Community-Acquired Pneumonia Admitted to Conventional Wards: Risk Factors, Clinical Features, and Outcomes

Background

Relevance of viral and bacterial coinfection (VBC) in non-intensive care unit (ICU) hospitalized adults with community-acquired pneumonia (CAP) is poorly characterized. We aim to determine risk factors, features, and outcomes of VBC-CAP in this setting.

Methods

This is a prospective cohort of adults admitted to conventional wards with CAP. Patients were divided into VBC-CAP, viral CAP (V-CAP), and bacterial CAP (B-CAP) groups. Independent risk and prognostic factors for VBC-CAP were identified.

Results

We documented 1123 episodes: 57 (5.1%) VBC-CAP, 98 (8.7%) V-CAP, and 968 (86.1%) B-CAP. Patients with VBC-CAP were younger than those with B-CAP (54 vs 71 years; P < .001). Chronic respiratory disease was more frequent in patients with VBC-CAP than in those with V-CAP (26.3% vs 14.3%%; P = .001). Among those with influenza (n = 153), the VBC-CAP group received empirical oseltamivir less often (56.1% vs 73.5%; P < .001). Patients with VBC-CAP also had more respiratory distress (21.1% VBC-CAP; 19.4% V-CAP, and 9.8% B-CAP; P < .001) and required ICU admission more often (31.6% VBC-CAP, 31.6% V-CAP, and 12.8% B-CAP; P < .001). The 30-day case-fatality rate was 3.5% in the VBC-CAP group, 3.1% in the V-CAP group, and 6.3% in the B-CAP group (P = .232). Furthermore, VBC-CAP was associated with severity criteria (odds ratio [OR], 5.219; P < .001) and lack of empirical oseltamivir therapy in influenza cases (OR, 0.401; P < .043).

Conclusions

Viral and bacterial coinfection-CAP involved younger patients with comorbidities and with poor influenza vaccination rate. Patients with VBC-CAP presented more respiratory complications and more often required ICU admission. Nevertheless, 30-day mortality rate was low and related either to severity criteria or to delayed initiation of oseltamivir therapy.

Defining Community-Acquired Pneumonia as a Public Health Threat: Arguments in Favor from Spanish Investigators

Despite advances in its prevention, pneumonia remains associated with high morbidity, mortality, and health costs worldwide. Studies carried out in the last decade have indicated that more patients with community-acquired pneumonia (CAP) now require hospitalization. In addition, pneumonia management poses many challenges, especially due to the increase in the number of elderly patients with multiple comorbidities, antibiotic-resistant pathogens, and the difficulty of rapid diagnosis. In this new call to action, we present a wide-ranging review of the information currently available on CAP and offer some reflections on ways to raise awareness of this disease among the general public. We discuss the burden of CAP and the importance of attaining better, faster microbiological diagnosis and initiating appropriate treatment. We also suggest that closer cooperation between health professionals and the population at large could improve the management of this largely preventable infectious disease that takes many lives each year.

Early and Late Cardiovascular Events in Patients Hospitalized for Community-Acquired Pneumonia

INTRODUCTION

Community-acquired pneumonia increases the risk of cardiovascular events (CVE). The objective of this study was to analyze host, severity, and etiology factors associated with the appearance of early and late events and their impact on mortality.

METHOD

Prospective multicenter cohort study in patients hospitalized for pneumonia. CVE and mortality rates were collected at admission, 30-day follow-up (early events), and one-year follow-up (late events).

RESULTS

In total, 202 of 1,967 (10.42%) patients presented early CVE and 122 (6.64%) late events; 16% of 1-year mortality was attributed to cardiovascular disease. The host risk factors related to cardiovascular complications were: age ≥65 years, smoking, and chronic heart disease. Alcohol abuse was a risk factor for early events, whereas obesity, hypertension, and chronic renal failure were related to late events. Severe sepsis and Pneumonia Severity Index (PSI) ≥3 were independent risk factors for early events, and only PSI ≥3 for late events. Streptococcus pneumoniae was the microorganism associated with most cardiovascular complications. Developing CVE was an independent factor related to early (OR 2.37) and late mortality (OR 4.05).

CONCLUSIONS

Age, smoking, chronic heart disease, initial severity, and S. pneumoniae infection are risk factors for early and late events, complications that have been related with an increase of the mortality risk during and after the pneumonia episode. Awareness of these factors can help us make active and early diagnoses of CVE in hospitalized CAP patients and design future interventional studies to reduce cardiovascular risk.

Simultaneous Depression of Immunological Synapse and Endothelial Injury is Associated with Organ Dysfunction in Community-Acquired Pneumonia

Rationale: A depressed expression of antigen presentation is, along with endothelial dysfunction, a recognized signature of severe community-acquired pneumonia (CAP). We aimed to evaluate the expression of a number of genes involved in the immunological synapse in non-critically ill CAP patients with or without organ dysfunction and to profile endothelial biomarkers such as proendothelin-1 (proET1) and proadrenomedullin (proADM). Methods: A nested study in a prospective cohort in CAP patients was performed. Expression levels of major histocompatibility complex class II DR alpha (HLA-DRA), CD40 ligand (CD40LG), CD3E, CD28, and inducible T-cell costimulator (ICOS) were quantified by using droplet digital polymerase chain reaction and endothelial biomarkers by immunofluorescence. Results: Ninety-four patients were included, 44.7% of whom had organ failure in one or more organs. A significant decrease in the expression of the five genes with increased levels of proadrenomedullin (proADM) and proendothelin-1 (proET1) was found in CAP with organ failure. The depressed expression of HLA-DRA (odds ratio (OR), 2.94), CD40LG (OR, 3.90), and CD28 (OR, 3.48) was independently associated with organ failure after adjustment for age, Charlson score, and severity. Conclusions. CAP with organ failure showed depressed expression of immunological synapse genes with increased levels of biomarkers denoting endothelial damage. Simultaneous profiling of immunological and endothelial signatures could help in the early identification of organ failure in CAP and in the implementation of personalized treatment.

Lymphopenic community-acquired pneumonia is associated with a dysregulated immune response and increased severity and mortality

OBJECTIVES

Lymphopenic (<724 lymphocytes/µL) community-acquired pneumonia (L-CAP) is an immunophenotype with an increased risk of mortality. We aimed to characterize the l-CAP immunophenotype though lymphocyte subsets and the inflammatory response and its relationship with severity at presentation and outcome.

METHODS

Prospective study of 217 immunocompetent patients hospitalized for CAP. Lymphocyte subsets (CD4⁺, CD8⁺, CD19⁺, and natural killer [NK] cells) and inflammatory cytokines were analyzed on days 1 and 4, and immunoglobulin subclasses were analyzed on day 1 in a nested group.

RESULTS

39% of patients showed l-CAP, with decreased levels of all lymphocyte subsets with a partial recovery of CD4⁺ and CD8⁺ cells by day 4. l-CAP patients exhibited higher initial severity and systemic levels of interleukin (IL)-8, IL-10, granulocyte colony-stimulating factor, and monocyte chemoattractant protein-1. Initial IgG2 levels were lower in patients with <724 lymphocytes/µL and positively correlated with ALC, CD4⁺, and CD19⁺ cell counts. Low CD4⁺ counts (<129 cells/µL) also independently predicted 30-day mortality after adjusting for age, gender, and the CURB-65 score.

CONCLUSIONS

l-CAP is characterized by CD4⁺ depletion, a higher inflammatory response, and low IgG2 levels that correlated with greater severity at presentation and worse prognosis. l-CAP is an immunophenotype useful for rapidly recognizing severity.

Efficacy evaluation of iclaprim in a neutropenic rat lung infection model with methicillin-resistant Staphylococcus aureus entrapped in alginate microspheres

The objective of this study was to demonstrate the efficacy of iclaprim in a neutropenic rat lung infection model with methicillin-resistant Staphylococcus aureus (MRSA) entrapped in alginate beads. An inoculum of 5.25 × 10⁵ colony-forming units (CFU)/mL of S. aureus strain AH1252 was administered intratracheally to rats with prepared alginate bacteria suspensions. Beginning 2 h post-infection, rats received: (1) iclaprim 80 mg/kg (n = 16); (2) iclaprim 60 mg/kg (n = 16), or (3) vancomycin 50 mg/kg (n = 24), for 3 days via subcutaneous (SC) injection every 12 h. Twelve hours after the last treatment, rats were euthanized and lungs collected for CFU determination. Iclaprim administered at 80 mg/kg or 60 mg/kg or vancomycin 50 mg/kg SC twice a day for 3 days resulted in a 6.05 log₁₀ CFU reduction (iclaprim 80 mg/kg compared with control, p < 0.0001), 5.11 log₁₀ CFU reduction (iclaprim 60 mg/kg compared with control, p < 0.0001), and 3.42 log₁₀ CFU reduction, respectively, from the controls (p < 0.0001). Iclaprim 80 mg/kg and 60 mg/kg resulted in 2.59 and 1.69 log₁₀ CFU reductions, respectively, from vancomycin-treated animals (80 mg/kg iclaprim vs. vancomycin, p = 0.0005; 60 mg/kg iclaprim vs. vancomycin, p = 0.07). Animals receiving iclaprim, vancomycin, and controls demonstrated 100%, 91.7%, and 48.3% survival, respectively. In this neutropenic rat S. aureus lung infection model, rats receiving iclaprim demonstrated a greater CFU reduction than the controls or those receiving vancomycin.