Usefulness of combined chest and abdominal computed tomography for identification of infection sources in febrile patients without clinical clue

ABSTRACT

OBJECTIVE: This study examined the utility of combined chest and abdominal computed tomography (CT) for the identification of infection sources in acute febrile patients without clinical clues. The groups for whom combined CT was helpful and not were compared. In addition, the factors that affected the positive infection sources and predictors of the presence of infection sources when performing combined CT was investigated. METHODS: Acute febrile patients without clinical clues from a basic examination and the confirmation procedure were investigated prospectively for 6 months. A range of factors, such as demographic factors, duration of fever, vital signs, presence of prior medical treatment, inflammatory markers, and several sepsis prediction tools, were analyzed. RESULTS: Of the 87 patients, 32 (36.8%) tested positive for infection sources on combined CT, whereas 55 (63.2%) tested negative. The mean age, heart rate, procalcitonin (PCT) level, and proportion of the patients aged ≥65 years showed significant differences between the infection source-positive group and infection source-negative group (P=0.027, P=0.008, P=0.035, and P=0.026, respectively). The factors that affected the positive results for infection sources on combined CT included age (odds ratio [OR], 1.047; P=0.011), absence of chronic disease (OR, 0.157; P=0.045), and heart rate (OR, 1.056; P=0.030). Analysis of the receiver-operating characteristic curve showed that age (area under the curve [AUC], 0.630; P=0.041) and heart rate (AUC, 0.659; P=0.008) were significant predictive factors of positive results for infection sources. On the other hand, their predictive powers were poor, and PCT did not show a significant result (AUC, 0.565; P=0.351). CONCLUSION: In patients with underlying chronic disease, older age, increased heart rate due to fever, or a high PCT level, combined CT can be used to identify infection sources when its possible clinical benefits are considered to be high.