Background: For febrile children who are evaluated in a pediatric emergency department (PED), blood culture can be considered the laboratory criterion standard to detect bacteremia. However, high rates of negative, false-positive, or contaminated blood cultures in children often result in this testing being noncontributory. This study determined the factors associated with true-positive blood cultures in children.
Methods: This retrospective study was conducted at a tertiary medical center's PED. The blood culture use reports were prepared by an infectious disease specialist and were classified as bacteremia, nonbacteremia, and contamination.
Results: We registered a total of 239,459 PED visits during the 8-year period, and 21,841 blood culture samples were taken. Of the laboratory test studies, higher C-reactive protein (CRP) levels and lower hemoglobin levels were observed in the bacteremia group compared with other groups (all P < 0.001). The cut-off value calculated for each age group was adjusted for better clinical usage and significantly improved the blood culture clinical utility documented in the following age groups: 0 to 1 years (CRP level = 30 mg/L, odds ratio [OR] = 5.4, P < 0.001), 1 to 3 years (CRP level = 45 mg/L, OR = 3.7, P < 0.001), and 12 to 18 years (CRP level = 50 mg/L, OR = 6.3, P = 0.006). Using the CRP cut-off value established in this study, we could reduce the blood culture samples in the PED by 14,108 (64.6%).
Conclusions: This study provides new evidence that CRP may be a useful indicator for blood culture sampling in certain age groups and may help improve the efficiency of blood culture in the PED.