Etiology and Factors Contributing to the Severity and Mortality of Community-acquired Pneumonia

Abstract

Objective Community-acquired pneumonia (CAP) remains a major cause of death. No studies have reported the use of rapid influenza diagnostic tests (RIDT) for the etiological diagnosis, and the factors contributing to severity and mortality have not yet been fully investigated. The aim of this study was to review the etiologies of CAP using RIDT and to identify risk factors related to the severity and mortality of the disease. Methods This retrospective study assessed these factors in hospitalized patients, with special emphasis on microbial etiology. Results A total of 1,032 patients aged 63.9±18.3 years were studied, 66.2% of whom were men. Microbial identification was obtained in 57.0% of the cases. The most frequent causative microbial agents were Streptococcus pneumoniae, Mycoplasma pneumoniae and the influenza virus, and the second most frequent pathogens in the patients with severe CAP and the non-survivors were S. pneumoniae and the influenza virus. Age (! 65 years), chronic obstructive pulmonary disease, congestive heart failure, diabetes mellitus, dementia and Legionella spp. infection and polymicrobial infection were each found to be independent factors related to severity in the multivariate analysis, whereas "unidentified pathogen" was found to be an independent factor for non-severe CAP. Age (! 65 years), chronic pulmonary aspergillosis, post-lung cancer surgery and severe CAP were found to be independent factors for non-survival according to a multivariate analysis. Conclusion In addition to S. pneumoniae, the influenza virus was a frequent cause of CAP overall and a frequent causative pathogen in both severe cases of CAP and non-survivors. Legionella spp. infection and polymicrobial infection were found to be an independent factor for the severity of CAP along with advanced age and certain comorbidities. An advanced age, certain respiratory comorbidities and severe CAP were found to be important independent factors for the mortality of CAP.

Predictors of Mortality Among U.S. Veterans With Streptococcus Pneumoniae Infections

“…Dementia has been shown to increase risk of developing pneumococcal infection as well as increased disease severity, likely due to an increased risk of aspiration similar to neurologic disorders. 2,34,38 A retrospective study of more than 1,000 patients with a mean age of 64 years showed that dementia was an independent predictor of increased pneumococcal infection severity (OR=4.23, 95% CI=1.24, 14.4), but was not a significant predictor of mortality. 38 However, severe infection, which was assessed in the aforementioned study as well as in this study via invasive disease and intensive care unit treatment, was predictive of mortality.…”

“…2,34,38 A retrospective study of more than 1,000 patients with a mean age of 64 years showed that dementia was an independent predictor of increased pneumococcal infection severity (OR=4.23, 95% CI=1.24, 14.4), but was not a significant predictor of mortality. 38 However, severe infection, which was assessed in the aforementioned study as well as in this study via invasive disease and intensive care unit treatment, was predictive of mortality. Although dementia was only significant in the predictive model during hospitalization, the results of this study support the already identified association between dementia and poor outcomes in the setting of pneumococcal infection.…”

Etiology and Factors Contributing to Mortality in Healthcare-associated Pneumonia: A Single-center Study

“…Characteristics of HCAP patients were compared with those of CAP patients hospitalized in our institution during the same period 5 .…”

Immunogenicity and safety of the 13-valent pneumococcal conjugate vaccine compared to the 23-valent pneumococcal polysaccharide vaccine in elderly Japanese adults

“…1 In Japan, S pneumoniae is the most common etiologic agent of community-acquired pneumonia (CAP), associated with 24%-39% of all cases. [2][3][4] In 2012, pneumonia was the third leading cause of death among the Japanese elderly 65 years of age (98.8 cases per 100,000). 5 Adult invasive pneumococcal disease (IPD) surveillance was initiated in Japan in 2013.…”