Seminars in respiratory and critical care medicine
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Semin Respir Crit Care Med · Dec 2016
ReviewThe Role of Streptococcus pneumoniae in Community-Acquired Pneumonia.
Streptococcus pneumoniae (the pneumococcus) remains one of the most common causes of bacterial community-acquired pneumonia (CAP), encompassing infections mild enough to be treated on an outpatient basis, as well as those requiring hospital care, or even intensive care unit admission. This microorganism is associated with a significant burden of disease, causing substantial morbidity and mortality worldwide, and generating considerable health-care costs. ⋯ Such risk factors include extremes of age, lifestyle factors, including smoking and alcohol abuse, and various underlying comorbid conditions, including congenital and acquired immunodeficiencies. This article will review various aspects of pneumococcal CAP, including the burden of pneumococcal disease, risk factors for pneumococcal infection, the occurrence of cardiovascular events in patients with pneumococcal CAP, the apparently pivotal role of pneumolysin, a major virulence factor of the pneumococcus, in the pathogenesis of severe infection and associated cardiac dysfunction, empiric antibiotic treatment for pneumococcal CAP, as well as adjunctive therapies, specifically those which target pneumolysin, and, finally, the mortality of such infections.
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Semin Respir Crit Care Med · Dec 2016
ReviewNonantibiotic Adjunctive Therapies for Community-Acquired Pneumonia (Corticosteroids and Beyond): Where Are We with Them?
Community-acquired pneumonia (CAP) is a leading cause of hospitalization, morbidity, and mortality. Despite advances in antibiotic treatments, mortality among patients with CAP is still high. For this reason, interest has been focused on nonantibiotic therapeutic measures directed to the host response rather than the microorganism. ⋯ In addition, some studies using statins also suggested improved outcomes due to its anti-inflammatory effect in CAP, although this requires further research. Other adjunctive therapies such as immunoglobulins and stem cells are being explored, but are not yet in the stage of clinical trials. In summary, the use of corticosteroids and other adjuvant treatments are promising in CAP, but more studies are needed to determine their impact on mortality.
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Semin Respir Crit Care Med · Dec 2016
ReviewRole of Atypical Pathogens in the Etiology of Community-Acquired Pneumonia.
Atypical pneumonia has been described for over 100 years, but some of the pathogens attributed to it have been identified only in the past decades. The most common pathogens are Chlamydia pneumoniae, Mycoplasma pneumoniae, and Legionella pneumophila. The epidemiology and pathophysiology of these three pathogens have been studied since their discovery, and are reviewed herein to provide better insight when evaluating these patients, which hopefully translates into improved care. ⋯ Treatment is missed if an empiric regimen includes only monotherapy with a β-lactam antimicrobial; so, many country guidelines, including the Infectious Diseases Society of America/American Thoracic Society guidelines for community-acquired pneumonia, recommend using a regimen containing either a macrolide or a fluorinated quinolone. Once an atypical pathogen has been identified, evidence trends toward favoring a quinolone, but more data are needed to confirm. The concept of using combination therapy in severe patients is also explored.