Utility of blood cultures in community-acquired pneumonia requiring hospitalization: influence of antibiotic treatment before admission

AbstractIt has been previously shown that antibiotics given before hospitalization significantly reduce the proportion of positive blood cultures in community-acquired pneumonia (CAP). The aim of this prospective study was to compare the utility and cost-benefits of blood cultures in patients, hospitalized for moderate CAP, who had or had not received antibiotic therapy prior to admission.During 1 year, 53 patients were included and separated into two groups: group 1 patients had not received antibiotic treatment prior to admission (n=30), whereas group 2 patients had been treated with antibiotics (n=23). Within the first 48 hours, a set of blood cultures was collected if the body temperature was higher than 38·5°C or in the case of shaking chills.A total of 136 blood cultures was collected; 74 in group 1 and 62 in group 2. Bacteraemia was significantly more frequent in group 1 than in group 2, 530 patients vs. 023, respectively (P