The Clinical Utility of Blood Cultures by Pneumonia Severity Index for Patients with Community-Acquired Pneumonia in the Emergency Department

ABSTRACT

PURPOSE: Community-Acquired Pneumonia (CAP) is a common cause of mortality and serious morbidity. Regardless of the condition of the patients, almost all are hospitalized. And it seems to be a standard procedure to obtain blood cultures before the administration of antibiotics in suspected pneumonic patients. Recent studies show that the blood cultures don't affect the treatment of the patients with CAP. Accordingly, this study was designed to examine the usefulness of the blood cultures routinely performed and to evaluate the stratification of the patients with CAP by Pneumonia Severity Index (PSI) in the Emergency Department (ED). METHODS: Research subjects were patients over 16 years old who had been diagnosed with CAP in a general hospital between January and December 2008 and were admitted by way of the ED. We evaluated their records retrospectively. RESULTS: A total of 261 patients were diagnosed with CAP. According to the PSI, 155 (59%) of the 261 were classified as being in the low risk group and 106 (41%) in the high risk group. Blood cultures were positive in 13 of 261 (5%). Three of 13 patients belonged to the low risk group, and 10 to the high risk group. Antibiotics were changed in 43 of 261 patients. Nineteen of those belonged to the low risk group and 24 to the high risk group. Of the 13 bacteremic patients, blood cultures results altered therapy for 4 patients. CONCLUSION: Most often, blood cultures performed in the ED do not alter the therapy of patients with CAP. But we do recommend blood cultures for the high risk group.