摘要
BACKGROUND： Blood cultures （BC ） are commonly ordered during the initial assessment ofpatients with community-acquired pneumonia （CAP）, yet their yield remains low. Selective use of BCwould allow the opportunity to save healthcare resources and avoid patient discomfort. The studywas to determine what demographic and clinical factors predict a greater likelihood of a positiveblood culture result in patients diagnosed with CAP.METHODS： A structured retrospective systematic chart audit was performed to comparerelevant demographic and clinical details of patients admitted with CAP, in whom blood culture resultswere positive, with those of age, sex, and date-matched control patients in whom blood cultureresults were negative.RESULTS： On univariate analysis, eight variables were associated with a positive BC result.After logistic regression analysis, however, the only variables statistically significantly associatedwith a positive BC were WBC less than 4.5 x 109/L [likelihood ratio （LR）： 7.75, 95% CI=2.89-30.39], creatinine 〉106 !mol/L （LR： 3.15, 95%CI=1.71-5.80）, serum glucose〈6.1 mmol/L （LR： 2.46,95%CI=1.14-5.32）, and temperature 〉 38 °C （LR： 2.25, 95% CI =1.21-4.20）. A patient with all of thesevariables had a LR of having a positive BC of 135.53 （95% CI=25.28-726.8） compared to patientswith none of these variables.CONCLUSIONS： Certain clinical variables in patients with CAP admitted to hospitals doappear to be associated with a higher probability of a positive yield of BC, with combinations of thesevariables increasing this likelihood. We have identified a subgroup of CAP patients in whom bloodcultures are more likely to be useful.
