The influence of age and gender on the population-based incidence of community-acquired pneumonia caused by different microbial pathogens.

OBJECTIVES: To determine the population-based incidence of community-acquired pneumonia (CAP) in adults and to assess the relative importance of age and gender on the incidence of infections caused by different microbial pathogens. METHODS: A two-year prospective study in a well-defined geographic area of the Spanish Mediterranean coast. RESULTS: The overall incidence rate of CAP was 12 cases (95% CI 11.25-13.45) per 10,000 person-years. Incidence rates increased by age (p<0.0001) and they were higher in males (16 versus 9 cases per 10,000 person-years; p<0.0001). The rate was especially high among males aged > or = 75 years (87 cases per 10,000 person-years). The incidence of pneumococcal pneumonia increased significantly with ageing and it was particularly high among people aged > or = 75 years (10 cases per 10,000 person-years). Very elderly people had also a 15-fold higher incidence of CAP associated with influenza virus and a 5-fold higher incidence of infections by Chlamydophila spp., than young adults. The incidence of infections with Legionella pneumophila also increased with age and it was 10 times higher in males. In contrast, the incidence of pneumonia caused by Mycoplasma pneumoniae was unrelated to age and gender. CONCLUSIONS: Age and gender have a strong influence on the overall incidence of CAP and on the incidence of pneumonia caused by the main microbial pathogens, including not only Streptococcus pneumoniae, but also influenza virus, Chlamydophila spp. and L. pneumophila. Ageing is associated with a higher risk of acquiring pneumonia by S. pneumoniae, influenza virus and Chlamydophila spp., whereas male gender increases greatly the incidence of L. pneumophila and Chlamydophila spp.

[Usefulness of acute-phase proteins in community-acquired pneumonia]. / Reactantes de fase aguda en la neumonía adquirida en la comunidad.

BACKGROUND AND OBJECTIVE: We aimed to study the usefulness of acute-phase proteins in the evolution and microbial diagnosis of community-acquired pneumonia (CAP). PATIENTS AND METHOD: One-year prospective study of CAP. Plasma levels of C reactive protein (CRP), erythrocyte sedimentation rate (ESR) and fibrinogen were measured on admission in all patients with CAP. RESULTS: 240 cases of CAP were included in the study. ESR was higher in patients who developed pleural effusion (p = 0.03). A value of ESR > 120 mm/h was associated with a higher likelihood of having a CAP complicated with pleural effusion (odds ratio = 3.80; 95% confidence interval, 1.37-10.49, p = 0.006). Baseline concentrations of CRP, ESR and fibrinogen were higher in patients who developed empyema. CRP and fibrinogen levels were significantly higher in patients with Legionella pneumophila pneumonia, while pneumococcal pneumonia was associated with a higher ESR value. CONCLUSIONS: Some frequently used acute-phase proteins can be useful in the prediction of pleural complications and in the approach to the etiological diagnosis of CAP.

Reactantes de fase aguda en la neumonía adquirida en la comunidad / Usefulness of acute-phase proteins in community-acquired pneumonia

FUNDAMENTO Y OBJETIVO: Estudiar la utilidad de los reactantes de fase aguda tradicionales como predictores pronósticos y de la etiología de la neumonía adquirida en la comunidad (NAC). PACIENTES Y MÉTODO: Estudio prospectivo de la NAC en un área sanitaria durante un año. Se determinaron las concentraciones plasmáticas de proteína C reactiva (PCR) y fibrinógeno y la velocidad de sedimentación globular (VSG) en el momento del diagnóstico de la NAC. RESULTADOS: Se estudió a 240 pacientes con NAC. En los casos que se complicaron con derrame pleural la VSG fue más elevada (p = 0,03). El hecho de que ésta fuera superior a 120 mm/h se asoció a una mayor probabilidad de NAC complicada con derrame pleural (odds ratio = 3,80; intervalo de confianza del 95 por ciento, 1,37-10,49; p = 0,006). Los valores basales de PCR, VSG y fibrinógeno fueron más altos en los pacientes que desarrollaron con posterioridad un empiema. Las neumonías por Legionella presentaron concentraciones más elevadas de fibrinógeno y PCR, y las neumocócicas se asociaron con valores más altos de VSG. CONCLUSIONES: Los reactantes de fase aguda tradicionales pueden ser útiles en la predicción de complicaciones pleurales de la NAC y orientar en el diagnóstico etiológico (AU)

Evaluation of the immunochromatographic Binax NOW assay for detection of Streptococcus pneumoniae urinary antigen in a prospective study of community-acquired pneumonia in Spain.

We evaluated the Binax NOW rapid immunochromatographic membrane test (ICT) for detection of Streptococcus pneumoniae urinary antigen in a population-based prospective study of adults with community-acquired pneumonia (CAP). ICT was performed with urine samples obtained from 452 (91.7%) of 493 patients enrolled. Pneumococcal antigen was detected in 19 (70.4%) of 27 patients with pneumococcal pneumonia. The test results were more frequently positive for patients who had not received antibiotics before testing (26.6% vs. 12.1%; P=.002). Only 16 (10.3%) of 156 samples obtained from patients with nonpneumococcal pneumonia yielded a positive result. Of the 269 patients who had pneumonia with no pathogen identified, antigen was detected in 69 (25.7%). With conventional microbiological criteria used as the "gold standard," the test had a sensitivity of 70.4% and a specificity of 89.7%. Testing concentrated urine samples with the ICT may be a useful technique for rapid diagnosis of pneumococcal pneumonia in adults with CAP.