Community-acquired pneumonia (CAP) remains the leading cause of death from infectious diseases both in developed and in developing countries. There are few prospective studies on CAP in Latin America and detailed information on its etiology is required for the formulation of local guidelines.The aim of this study was to determine the etiology and to investigate prognostic factors of CAP in immunocompetent hospitalized adult patients.
Over a 3-year period, between January 1, 2003, and February 28, 2006, we prospectively studied 150 consecutive patients with CAP admitted to the University Hospital of Santa Maria, Brazil. Patient severity of illness was assessed by the pneumonia severity index (PSI). Clinical data and systematic laboratory evaluation to identify the microbial etiology and prognostic factors were recorded.
The mean age (± SD) was 54 ± 20.6 years. Sixty percent of the patients was male, comorbid illnesses were present in 110 patients (73.6%). Ninety-five patients (63.6%) had a PSI IV or V and 33 (21.8%) were admitted to intensive care unit (ICU). An etiological agent was identified in 82 cases (54.5%). The most frequent isolated pathogens were Streptococcus pneumoniae (20.7%), Staphylococcus aureus (12.7%) and Haemophilus influenzae (7,3%). Antibiotic treatment prior to admission was significantly associated with unknown etiology. Twenty patients (13.3%) died. In multivariate analysis, three prognostic factors on admission were associated with in-hospital mortality: age > 65 years, PSI index ≥ IV, and admission to ICU.
In this study, Streptococcus Pneumoniae was the most common identified pathogen, followed by Staphylococcus aureus and Haemophilus influenzae. Age > 65 years, PSI ≥ IV and admission in ICU were the prognostic factors statistically associated with higher mortality.
It is important to determine the local etilogical agents of CAP for the formulation of treatment recommendations and preventive measures. The incidence of Staphylococcus aureus was higher than previously described. In patients with risk factors, the empirical therapy to this agent is probably warranted.
Gustavo Michel, No Financial Disclosure Information; No Product/Research Disclosure Information