Sepsis Prediction: Biomarkers Combined in a Bayesian Approach

Abstract

Sepsis is a serious public health problem. sTREM-1 is a marker of inflammatory and infectious processes that has the potential to become a useful tool for predicting the evolution of sepsis. A prediction model for sepsis was constructed by combining sTREM-1, CRP, and a leukogram via a Bayesian network. A translational study carried out with 32 children with congenital heart disease who had undergone surgical correction at a public referral hospital in Northeast Brazil. In the postoperative period, the mean value of sTREM-1 was greater among patients diagnosed with sepsis than among those not diagnosed with sepsis (394.58 pg/mL versus 239.93 pg/mL, p < 0.001). Analysis of the ROC curve for sTREM-1 and sepsis revealed that the area under the curve was 0.761, with a 95% CI (0.587-0.935) and p = 0.013. With the Bayesian model, we found that a 100% probability of sepsis was related to postoperative blood concentrations of CRP above 71 mg/dL, a leukogram above 14,000 cells/μL, and sTREM-1 concentrations above the cutoff point (283.53 pg/mL). The proposed model using the Bayesian network approach with the combination of CRP, leukocyte count, and postoperative sTREM-1 showed promise for the diagnosis of sepsis.

Keywords: Bayes theorem; biomarkers; cardiac surgery; sTREM-1; sepsis.

Figure 1

ROC curve analysis of postoperative sTREM-1 expression versus the diagnosis of sepsis in children undergoing cardiac surgery (n = 32).

Figure 2

Bayesian network model structure showing the relationships between postoperative CRP levels, WBC counts, and sTREM-1 levels and the diagnosis of sepsis in children undergoing cardiac surgery (n = 32).