Value of combining the serum d-lactate, diamine oxidase, and endotoxin levels to predict gut-derived infections in cancer patients

Abstract Objective This is a retrospective observational cohort study. The objective of this retrospective observational cohort study was to evaluate the value of the combined serum d-lactic acid, diamine oxidase (DAO), and endotoxin levels to predict intestinal barrier impairment and gut-derived infection (GDI) in cancer patients. Methods Cancer patients receiving chemotherapy or palliative care treatment at our hospital were enrolled in the study. The serum concentrations of DAO, d-lactic acid, and endotoxin were determined using the intestinal barrier function biochemical index analysis system. The patients' infection information came from the hospital's Medicom Prescription Automatic Screening System and the medical records. Three hundred fifty-three cancer patients were included in the study (53.8% female, 73.7% cancer stage IV, 27.8% had bowel obstruction). Results The total incidence of GDI was 33.4% (118/353). The median length of hospital stay was 16 days for patients with GDI, compared with 7 days for patients without GDI (P < 0.001). The media hospitalization costs were ¥27,362.35 for patients with GDI compared with ¥11,614.08 for patients without GDI (P < 0.001). The serum concentrations of DAO, d-lactic acid, and endotoxin were significantly higher in patients with GDI. As malignant bowel obstruction (MBO) worsened, the concentrations of DAO, d-lactic acid, and endotoxin increased. Multivariate logistic regression models revealed that the DAO, endotoxin, IL-6, and C-reactive protein levels were significantly associated with an increased risk of GDI. In addition, we also found a fivefold increased risk of infection in patients with MBO compared with those without bowel obstruction (OR = 6.210, P < 0.001). All of the areas under the receiver operating characteristic curve (AUCs) for DAO, d-lactate, and endotoxin to predict GDI were <0.7 (AUC = 0.648, P < 0.001; AUC = 0.624, P < 0.01; AUC = 0.620, P < 0.01, respectively). However, when the parameters were combined (DAO + d-lactate + endotoxin), the predictive power increased significantly (AUC = 0.797, P < 0.001). Moreover, combining these intestinal barrier indicators and the presence of MBO had better power to predict GDI than either alone (AUC = 0.837, P < 0.001). Conclusions Combining the serum DAO, d-lactic acid, and endotoxin levels was a better predictor of GDI than any of the indicators alone, and combining these with the diagnosis of MBO could further improve the efficacy for predicting GDI.