The contribution of blood cultures to the clinical management of adult patients admitted to the hospital with community-acquired pneumonia: a prospective observational study.

<bold>Study Objective: </bold>To assess the clinical usefulness of blood cultures (BCs) in the management of patients hospitalized with community-acquired pneumonia (CAP).<bold>Design: </bold>A prospective, observational study to investigate the contribution of BCs to the management and outcomes of adult patients presenting with CAP.<bold>Setting: </bold>Nineteen Canadian hospitals.<bold>Patients: </bold>Adults admitted to the hospital with CAP between January 1, 1998, and July 31, 1998.<bold>Interventions: </bold>The courses of therapy in patients for whom BC results yielded organisms considered to be clinically significant were analyzed to determine whether the BCs had contributed to management or outcome.<bold>Measurements and Results: </bold>Forty-three of 760 patients had significantly positive BC results. Patients with CAP who had BCs performed had a 1.97% chance (15 of 760 patients) of having a change of therapy directed by BC results. Patients in whom BCs yielded positive results had a 34.8% chance (15 of 43 patients) of having a change in therapy determined by BC results, and had a 58.1% chance (25 of 43 patients) of having a course of therapy contraindicated by BC results. Severity of illness, as measured by the pneumonia severity index, correlated poorly with the yield of BCs. BC results were positive in 8.0% of patients in risk classes I and II, 6.2% of patients in risk class III, 4.6% of patients in risk class IV, and 5.2% of patients in risk class V.<bold>Conclusion: </bold>BCs have limited usefulness in the routine management of patients admitted to the hospital with uncomplicated CAP. [ABSTRACT FROM AUTHOR]