PERIPHERAL BLOOD RDW AND SERUM LEVELS OF SUPAR, BNP AND PCT IN PROGNOSTIC EVALUATION OF ICU PATIENTS WITH A BACTERIAL INFECTION IN THE BLOODSTREAM

Renguo Yang, Weiwei He, Tingting Luo^*

Department of Infections, Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China

Objective: To evaluate prognostic indicators of ICU patients with acute bloodstream bacterial infections; these indicators are peripheral blood red blood cell distribution width (RDW), serum soluble urinary creatinase-type plasminogen activator receptors (suPAR), B-type natriuretic peptides (BNP), and C-reactive proteins (PCT).

Methods: Ninety patients with bloodstream bacterial infections treated in the hospital’s ICU from October 2018 to October 2019 were allocated to the study group; the group was then divided into two groups according to each patient’s prognosis: survival (n = 56) and death (n = 34). Simultaneously, 30 healthy participants who had undergone physical examination in the hospital’s physical examination centre were allocated to the control group. Levels of SuPAR were detected using an enzyme-linked immunosorbent assay, CRP levels were detected using ultra-sensitive latex-enhanced immune turbidimetry, and PCT levels were detected using the Chemiluminescence method. Levels of RDW were detected and calculated using a fully automatic immunoanalyser. Multivariate logistic regression was used to analyse influencing factors in the prognoses of patients with bloodstream bacterial infections, and the ROC curve was used to analyse the prognostic value of RDW, suPAR, BNP, PCT for patients with bloodstream bacterial infections.

Results: The levels of serum RDW, suPAR, BNP and PCT in patients in the study group were significantly higher than those in the control group, and the differences were statistically significant (P<0.01). The levels of serum RDW, suPAR, BNP and PCT in the death group were significantly higher than those in the survival group, and the differences were statistically significant (P<0.01). The Multivariate Logistic regression analysis showed that sCD163, hs-CRP, WBC, PCT, and CPIS scores were independent risk factors affecting the prognosis of patients with bloodstream bacterial infections (P<0.05). For patients with bloodstream bacterial infections, the ROC curve analysis showed that the AUC of RDW for patients with bloodstream bacterial infection was 0.742 and the optimal cut-off was 15.66; sensitivity at this point was 73.25% and specificity was 71.48%. The AUC of suPAR was 0.893 and the optimal cut-off value was 13.48 ng/ml; sensitivity at this point was 83.54%, and specificity was 85.17%. The AUC of PCT was 0.656 and the optimal cut-off value was 43.17 ng/ml; sensitivity at this point was 64.11% and specificity was 71.16%. The AUC of BNP was 0.875 and the optimal cut-off value was 315.68 pg/ml; sensitivity at this point was 81.25% and specificity was 84.71%.

Conclusion: The levels of RDW, suPAR, BNP, and PCT in the serum of patients with bloodstream bacterial infection were significantly increased; this suggests these indicators have value for assessing the prognosis of patients, especially suPAR and BNP.