Etiologies and treatment outcomes in patients hospitalized with community-acquired pneumonia (CAP) at Srinagarind Hospital, Khon Kaen, Thailand.

Local epidemiological data on the etiologies of in-patients who are hospitalized with CAP is needed to develop guidelines for clinical practice. This study was conducted to determine the pattern of microorganisms causing community-acquired pneumonia (CAP) in adult patients admitted to Srinagarind Hospital, Khon Kaen, Thailand, between January 2001 and December 2002. Altogether, 254 patients (124 males, 130 females) averaging 56.4 (SD 19.8) years were included. Eighty-six of them (33.8%) presented with severe CAP on initial clinical presentation. The etiologies for the CAP cases were discovered by isolating the organisms from the blood, sputum, pleural fluid, and other sterile sites. Serology for Chlamydia pneunmoniae and Mycoplasma pneumoniae were performed to diagnose current infection. The causative organisms were identified in 145 patients (57.1%). Streptococcus pneumoniae was the commonest pathogen, identified in 11.4% of the cases, followed by Burkholderia pseudomallei (11.0%) and Klebsiella pneumoniae (10.2%). The atypical pathogens, C. pneumoniae and M. pneumoniae, accounted for 8.7% and 3.9% of the isolates, respectively. Sixteen patients (6.3%) had dual infections; C. pneumoniae was the most frequent coinfecting pathogen. The average length of hospital stay was 12.9 (SD 14.0) days, with 27.9% staying more than 2 weeks. Overall, 83.9% of the patients improved with treatment, 10.2% did not improve and 5.9% died. The most common complications were acute respiratory failure (31.1%) and septic shock (20.9%). We conclude that initial antibiotic use should cover the atypical pathogens, C. pneumoniae and M. pneumoniae, in hospitalized CAP patients. B. pseudomallei is an endemic pathogen in Northeast Thailand, and should be considered in cases of severe CAP.