Published online Aug 28, 2020. doi: 10.3748/wjg.v26.i32.4857
Peer-review started: May 23, 2020
First decision: June 12, 2020
Revised: June 18, 2020
Accepted: July 30, 2020
Article in press: July 30, 2020
Published online: August 28, 2020
Patients with acute-on-chronic liver failure (ACLF) are prone to have bacterial infection. However, the diagnosis of infection is difficult in the ACLF population due to their specific clinico-pathophysiological features.
Early detection of bacterial infection and timely treatment are crucial in the management of ACLF. Therefore, it is important to identify a new biomarker or to develop a model to improve diagnostic efficiency.
This retrospective study aimed to develop a novel scoring system containing common biomarkers for the identification of bacterial infection in ACLF.
This was a retrospective study. Procalcitonin (PCT), white blood cells (WBC), proportion of neutrophils (N%), and C-reactive protein (CRP) were examined. Logistic regression was used to select variables for the scoring models and receiver operating characteristic curve (ROC) analysis was used to evaluate the diagnostic value of different indices.
This study included 386 patients with ACLF, 169 (43.78%) of whom had bacterial infection on admission. The area under the ROC (AUROC) of PCT, CRP, WBC and N% for the diagnosis of bacterial infection ranged from 0.637 to 0.692, with no significant difference between them. Logistic regression showed that only N%, PCT, and CRP could independently predict infection. A novel scoring system (infection score) comprised of N%, PCT and CRP was developed. The AUROC of the infection score was 0.740, which was significantly higher than that for the other four indices (infection score vs N%, PCT, CRP, and WBC, P = 0.0056, 0.0001, 0.0483 and 0.0008, respectively). The best cutoff point for the infection score was 4 points, with a sensitivity of 78.05%, a specificity of 55.29%, a positive predictive value of 57.91% and a negative predictive value of 76.16%.
The common indicators of infection, including WBC, N%, CRP, and PCT, did not perform well in ACLF as all the AUROCs were less than 0.7 and no differences were found between these indicators. A novel scoring system comprised of N%, PCT and CRP demonstrated higher accuracy for bacterial infection in ACLF than the indicators used alone.
Further validation of this scoring system is required in prospective studies.