VALUE OF ROUTINE MICROBIAL INVESTIGATION IN COMMUNITY-ACQUIRED PNEUMONIA TREATED IN A TERTIARY CARE CENTER

The study was conducted at a tertiary care and teaching hospital with about 200 beds for internal medicine. The objective was to determine t he diagnostic yield and value in directing antibiotic therapy of a rou tine microbial approach in patients with community-acquired pneumonia referred to a tertiary care center. We studied 93 episodes in a retros pective study, 69/93 (74%) cases were treated with at least one empiri cal antibiotic therapy prior to admission. Microbial investigation was performed in 83/93 cases (89%), An etiological agent was established in 19/83 (33%) cases including 7/50 (14%) by blood culture and 12/52 ( 23%) by serology, Bronchoscopy with 18 protected specimen brush and 20 bronchoalveolar lavage examinations was definitely diagnostic in only 1/25 (4%) cases, and this case was also identified by blood culture. 5/25 (20%) were probably diagnostic. Three pathogens, Streptococcus pn eumoniae, Mycoplasma pneumoniae and Legionella pneumophila, accounted for 15/19 (79%) of the identified agents, The diagnostic results direc ted a change in antibiotic therapy in 6/19 (32%) of cases with definit ely proven pathogens. 4/19 (21%) of cases would have been treated with an inappropriate regimen without diagnostic results, The diagnostic y ield of routine microbial investigation in pretreated patients is low. The routine approach reveals its limited value especially in patients with severe courses. The role of bronchoscopy remains to be defined f or patients with severe (and pretreated) community-acquired pneumonia.