Aspiration Pneumonia.

Aspiration pneumonia is a lower respiratory tract infection that results from inhalation of foreign material, often gastric and oropharyngeal contents. It is important to distinguish this from a similar entity, aspiration with chemical pneumonitis, as treatment approaches may differ. An evolving understanding of the human microbiome has shed light on the pathogenesis of aspiration pneumonia, suggesting that dysbiosis, repetitive injury, and inflammatory responses play a role in its development. Risk factors for aspiration events involve a complex interplay of anatomical and physiological dysfunctions in the nervous, gastrointestinal, and pulmonary systems. Current treatment strategies have shifted away from anaerobic organisms as leading pathogens. Prevention of aspiration pneumonia primarily involves addressing oropharyngeal dysphagia, a significant risk factor for aspiration pneumonia, particularly among elderly individuals and those with cognitive and neurodegenerative disorders.

Risk Factors and Algorithms for the Empirical Treatment of Hospital-Acquired Pneumonia and Ventilator-Associated Pneumonia.

Hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) continue to be major concerns for morbidity and mortality, especially in patients treated in the intensive care unit. With the rise in multidrug-resistant organisms, HAP and VAP treatment is challenged by the need for early appropriate treatment, with broad-spectrum agents, while still being aware of the principles of antibiotic stewardship. The two major society guidelines proposed a series of risk factors in their most recent guidelines to help identify patients who can most benefit from narrow- or broad-spectrum initial empiric antibiotic therapy. The guidelines reveal differences in the proposed risk factors and treatment approaches, as well as major similarities.

Initial antimicrobial management of sepsis.

Sepsis is a common consequence of infection, associated with a mortality rate > 25%. Although community-acquired sepsis is more common, hospital-acquired infection is more lethal. The most common site of infection is the lung, followed by abdominal infection, catheter-associated blood steam infection and urinary tract infection. Gram-negative sepsis is more common than gram-positive infection, but sepsis can also be due to fungal and viral pathogens. To reduce mortality, it is necessary to give immediate, empiric, broad-spectrum therapy to those with severe sepsis and/or shock, but this approach can drive antimicrobial overuse and resistance and should be accompanied by a commitment to de-escalation and antimicrobial stewardship. Biomarkers such a procalcitonin can provide decision support for antibiotic use, and may identify patients with a low likelihood of infection, and in some settings, can guide duration of antibiotic therapy. Sepsis can involve drug-resistant pathogens, and this often necessitates consideration of newer antimicrobial agents.

A Therapeutic Strategy for All Pneumonia Patients: A 3-Year Prospective Multicenter Cohort Study Using Risk Factors for Multidrug-resistant Pathogens to Select Initial Empiric Therapy.

BACKGROUND: Empiric therapy of pneumonia is currently based on the site of acquisition (community or hospital), but could be chosen, based on risk factors for multidrug-resistant (MDR) pathogens, independent of site of acquisition. METHODS: We prospectively applied a therapeutic algorithm based on MDR risks, in a multicenter cohort study of 1089 patients with 656 community-acquired pneumonia (CAP), 238 healthcare-associated pneumonia (HCAP), 140 hospital-acquired pneumonia (HAP), or 55 ventilator-associated pneumonia (VAP). RESULTS: Approximately 83% of patients were treated according to the algorithm, with 4.3% receiving inappropriate therapy. The frequency of MDR pathogens varied, respectively, with VAP (50.9%), HAP (27.9%), HCAP (10.9%), and CAP (5.2%). Those with ≥2 MDR risks had MDR pathogens more often than those with 0-1 MDR risk (25.8% vs 5.3%, P < .001). The 30-day mortality rates were as follows: VAP (18.2%), HAP (13.6%), HCAP (6.7%), and CAP (4.7%), and were lower in patients with 0-1 MDR risks than in those with ≥2 MDR risks (4.5% vs 12.5%, P < .001). In multivariate logistic regression analysis, 5 risk factors (advanced age, hematocrit <30%, malnutrition, dehydration, and chronic liver disease), as well as hypotension and inappropriate therapy were significantly correlated with 30-day mortality, whereas the classification of pneumonia type (VAP, HAP, HCAP, CAP) was not. CONCLUSIONS: Individual MDR risk factors can be used in a unified algorithm to guide and simplify empiric therapy for all pneumonia patients, and were more important than the classification of site of pneumonia acquisition in determining 30-day mortality. CLINICAL TRIALS REGISTRATION: JMA-IIA00146.

Future Research Directions in Pneumonia. NHLBI Working Group Report.

Pneumonia is a complex pulmonary disease in need of new clinical approaches. Although triggered by a pathogen, pneumonia often results from dysregulations of host defense that likely precede infection. The coordinated activities of immune resistance and tissue resilience then dictate whether and how pneumonia progresses or resolves. Inadequate or inappropriate host responses lead to more severe outcomes such as acute respiratory distress syndrome and to organ dysfunction beyond the lungs and over extended time frames after pathogen clearance, some of which increase the risk for subsequent pneumonia. Improved understanding of such host responses will guide the development of novel approaches for preventing and curing pneumonia and for mitigating the subsequent pulmonary and extrapulmonary complications of pneumonia. The NHLBI assembled a working group of extramural investigators to prioritize avenues of host-directed pneumonia research that should yield novel approaches for interrupting the cycle of unhealthy decline caused by pneumonia. This report summarizes the working group's specific recommendations in the areas of pneumonia susceptibility, host response, and consequences. Overarching goals include the development of more host-focused clinical approaches for preventing and treating pneumonia, the generation of predictive tools (for pneumonia occurrence, severity, and outcome), and the elucidation of mechanisms mediating immune resistance and tissue resilience in the lung. Specific areas of research are highlighted as especially promising for making advances against pneumonia.

Antibiotic treatment of hospital-acquired pneumonia: is it different from ventilator-associated pneumonia?

PURPOSE OF REVIEW: Hospital-acquired pneumonia (HAP) is a form of nosocomial pneumonia, distinct from ventilator-associated pneumonia (VAP). This review compares HAP and VAP, highlighting differences in natural history, risk factors, and bacteriology that necessitate a different approach to the therapy of HAP, compared with VAP. RECENT FINDINGS: HAP can arise out of the ICU, or in the ICU, and can lead to severe illness, including the need for intubation and mechanical ventilation. New American and European nosocomial pneumonia guidelines make therapy recommendations for HAP. The American guidelines recommend broader spectrum therapy than the European guidelines, but recent studies support the idea that not all HAP patients need antipseudomonal therapy. When the American guideline approach to HAP has been studied, it led to both overtreatment and inappropriate therapy for the identified pathogens. An algorithm, modified from the European guideline, proposes an approach to therapy that necessitates dual antipseudomonal therapy in less than 25% of all HAP patients. SUMMARY: Although more prospective therapy trials of HAP are needed, based on currently available data, it is possible to use an approach that provides appropriate therapy without the overuse of broad-spectrum therapy.

International ERS/ESICM/ESCMID/ALAT guidelines for the management of hospital-acquired pneumonia and ventilator-associated pneumonia: Guidelines for the management of hospital-acquired pneumonia (HAP)/ventilator-associated pneumonia (VAP) of the European Respiratory Society (ERS), European Society of Intensive Care Medicine (ESICM), European Society of Clinical Microbiology and Infectious Diseases (ESCMID) and Asociación Latinoamericana del Tórax (ALAT).

The most recent European guidelines and task force reports on hospital-acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) were published almost 10 years ago. Since then, further randomised clinical trials of HAP and VAP have been conducted and new information has become available. Studies of epidemiology, diagnosis, empiric treatment, response to treatment, new antibiotics or new forms of antibiotic administration and disease prevention have changed old paradigms. In addition, important differences between approaches in Europe and the USA have become apparent.The European Respiratory Society launched a project to develop new international guidelines for HAP and VAP. Other European societies, including the European Society of Intensive Care Medicine and the European Society of Clinical Microbiology and Infectious Diseases, were invited to participate and appointed their representatives. The Latin American Thoracic Association was also invited.A total of 15 experts and two methodologists made up the panel. Three experts from the USA were also invited (Michael S. Niederman, Marin Kollef and Richard Wunderink).Applying the GRADE (Grading of Recommendations, Assessment, Development and Evaluation) methodology, the panel selected seven PICO (population-intervention-comparison-outcome) questions that generated a series of recommendations for HAP/VAP diagnosis, treatment and prevention.

Using Ventilator-Associated Pneumonia Rates as a Health Care Quality Indicator: A Contentious Concept.

Pneumonia is a leading cause of hospital-acquired infections, although reported rates of ventilator-associated pneumonia (VAP) have been declining in recent years. A multifaceted infection prevention approach, using a "ventilator bundle," has been shown to reduce the frequency of VAP, while improving other patient outcomes. Because of difficulties in defining VAP, the Center for Medicare and Medicaid Service introduced a new streamlined ventilator-associated event (VAE) definition in 2013 for the surveillance of complications in mechanically ventilated patients. VAE measures are increasingly being measured by institutions in the United States in place of VAP rates and as a potential measure of the quality of intensive care unit (ICU) care. However, there is increased recognition that the streamlined definitions identify a different subset of patients than those identified by traditional VAP surveillance and that VAP prevention strategies may not impact all the causes of VAE. Also, VAP and VAE rates may not always reflect the quality of care in a given ICU, especially since patient factors, beyond the control of the hospital, may impact the rates of VAP and VAE. In this review, we discuss the issues related to VAP as a quality measure and the areas of uncertainty related to the new VAE definitions.

Improving outcomes in community-acquired pneumonia.

PURPOSE OF REVIEW: Community-acquired pneumonia (CAP) is a pervasive disease that is encountered in outpatient and inpatient settings. CAP is the leading cause of death from an infectious disease and accounts for significant worldwide morbidity and mortality. This update reviews current advances that can be used to promote improved outcomes in CAP. RECENT FINDINGS: Early recognition of CAP and its severe presentations, with appropriate site of care decisions, leads to reduced patient mortality. In addition to traditional prognostic tools, certain serum biomarkers can assist in defining disease severity and guide treatment and management strategies. The use of macrolides as part of combination antibiotic therapy has shown beneficial mortality effects across the CAP disease spectrum, especially for those with severe illness. When treating community-associated, methicillin-resistant Staphylococcus aureus pneumonia, use of an antitoxin antibiotic is likely to be valuable. Adjunctive therapy with corticosteroids may prevent delayed clinical resolution in selected patients with severe CAP. Recent data expand on the interaction of CAP with comorbid disease, particularly cardiovascular disease, and its impact on mortality in CAP patients. SUMMARY: Improved diagnostic tools, optimized treatment regimens, and enhanced understanding of CAP-induced perturbations in comorbid disease states hold promise to improve patient outcomes.

Principles of Antibiotic Management of Community-Acquired Pneumonia.

Community-acquired pneumonia (CAP) encompasses a broad spectrum of disease severity and may require outpatient, inpatient, or intensive care management. Successful treatment hinges on expedient delivery of appropriate antibiotic therapy tailored to both the likely offending pathogens and the severity of disease. This review summarizes key principles in starting treatment and provides recommended empiric therapy regimens for each site of care. In addition, we discuss the antimicrobial and anti-inflammatory role macrolides play in CAP, as well as specific information for managing individual CAP pathogens such as community-acquired methicillin-resistant Staphylococcus aureus and drug-resistant Streptococcus pneumoniae. We also examine several novel antibiotics being developed for CAP and review the evidence guiding duration of therapy and current best practices for the transition of hospitalized patients from intravenous antibiotics to oral therapy.