Clinical significance of a novel uric-acid-based biomarker in the prediction of disease activity and response to infliximab therapy in Crohn’s disease

Objectives Crohn's disease (CD) is an inflammatory bowel disease marked by a chronic remission-relapse cycle. Biomarkers are critical to reflect the bowel wall inflammation and detect the treatment response. Here, we investigated a new index—the ratio of neutrophil to uric acid (NUR)—as a predictor of CD activity and responses to infliximab (IFX) treatment.Methods Clinical and laboratory data were retrieved for CD patients and healthy control subjects from an electronic medical records database. Disease and endoscopic activity were determined using the Crohn's Disease Activity Index (CDAI) and Simple Endoscopic Score for Crohn's Disease (SES-CD), respectively.Results We found firstly that NUR was remarkably higher in CD patients (n = 162) than controls (n = 170) (0.27 ± 0.10 vs. 0.19 ± 0.04, p < .0001). NUR was positively correlated with disease activity and prior to treatment, it was lower in CD patients who responded to IFX than in those who did not (0.25 ± 0.07 vs. 0.38 ± 0.12, p = .0019). Pre-treatment NUR was effective in predicting the patients' responses to IFX (AUC = 0.8469, p = .0034).Conclusion The results of this study support the utility of NUR for detecting CD activity and predicting the response to IFX treatment.