Routine blood cultures from febrile outpatients. Use in detecting bacteremia.

Of 565 febrile patients examined in the emergency room of a metropolitan hospital, 210 had blood samples cultured (37.1%). Bacteremia was present in 9 of 86 patients who were admitted to the hospital but in only one of 124 patients who were not admitted (P less than .005). Thus, approximately 5% of febrile adult outpatients had bacteremia, and these patients were usually admitted before the results of the culture were known. Since positive cultures were found so infrequently in patients not admitted and were, therefore, of little value in guiding the treatment of these patients, we conclude that use of routine blood cultures to screen for bacteremia in unnecessary for febrile adult outpatients who are not admitted to the hospital.