Introduction: This study aimed to compare the accuracy of selected laboratory markers in assessing disease activity in patients with ulcerative colitis (UC). The analysis included serum IL-2, IL-4, IL-6, IL-10, IL-17, TNF-, IFN-, hsCRP, peripheral regulatory T cells, as well as fecal calprotectin and lactoferrin.
Patients and methods: A group of 45 adults with UC was enrolled in the study. Disease activity was assessed using the Mayo endoscopic index, while for clinical activity scoring, the Clinical Activity Index (CAI) was used. Concentrations of markers investigated were estimated by means of flow cytometry and enzyme-linked immunosorbent assays: the results were correlated with both indices.
Results: The study demonstrated that both fecal markers, i.e. calprotectin (r = 0.880, P<0.001) and lactoferrin (r = 0.799, P<0.001) correlated closely with the Mayo endoscopic score, and might be used to evaluate the severity of UC in the clinical setting. The correlation of these markers with CAI was also significant, with r = 0.831 for calprotectin (P<0.001) and r = 0.672 for lactoferrin (P<0.05). As for the other markers investigated, only IL-6 (r = 0.598, P<0.001), IL-17A (r = 0.587, P<0.005), and TNF- (r = 0.701, P<0.001) correlated closely with the Mayo endoscopic index. The correlation of the markers with CAI was also significant, though weaker, with r = 0.525 for IL-6 (P<0.001), r = 0.587 for IL-17A (P<0.05), and r = 0.624 for TNF- (P<0.001).
Discussion: Despite the fact, that UC is generally considered to be an IL-13-driven, Th2-like type of disease, markers of inflammation such as serum interleukin (IL)-6, IL-17, TNF-, fecal calprotectin and lactoferrin might be useful in assessing disease activity.