Clinical diagnostic value of fecal neopterin and calprotectin on the activity of inflammatory bowel disease / 医学研究生学报

ABSTRACT

Objective Fecal biomarkers have emerged as an important tool for assessing and monitoring disease activity in patients with inflammatory bowel disease ( IBD) .We aimed to investigate the diagnostic value of fecal neopterin and calprotectin in pa-tients with active inflammatory bowel disease and made comparison with that of serum C-reactive protein ( CRP) . Methods A total of 151 consecutive patients with IBD (84 CD and 67 UC) provided 2 gram fecal samples for the measurement of fecal neopterin( FNP) and calprotectin( FCP) concentrations and 2 milliliter blood samples for the serum C-reactive protein measurement before undergoing a colonoscopy.ELISA was applied in the measurement.Clinical disease activities were scored independently according to the Best Crohn′s Disease Activity Index(CDAI) in patients with CD, while the Modi-fied Mayo Scores in patients with UC.Comaprison was made in the relativity of each fecal marker and IBD activity score, the optimum value of diagnosing IBD acitivity as to each fecal marker, as well as sensitivity, specificity, moreover, receiver operating characteristic curve ( ROC) was drawn.50 healthy volunteers who received a normal colonoscopy were also enrolled as the control group and asked to give a 2 gram fresh stool sample. Results The FNP and FCP concentrations in patients with IBD were significantly higher than those in healthy control group(P<0.05).Both FNP and FCP concentrations differed significantly in clinically active IBD when compared with those in patients with inactive disease( P<0.001) .In CD patients, the correlation coefficients of FNP and FCP with CDAI were 0.55 and 0.59, respectively(P<0.001).In UC patients, the correlation coefficients of FNP and FCP with Mayo scores were 0.74 and 0.77, respectively( P<0.001) .The correlation coefficients of serum CRP in CD and UC patients with clinical scores were 0.49 and 0.60, respectively(P<0.001).The area under the ROC curve(AUC) of FNP and FCP for the diagnosis of clinical activity in pa-tients with CD were 0.75 and 0.80, respectively.The AUC of FNP and FCP in UC patients were 0.85 and 0.90, respectively.The AUC of serum CRP in patients with CD and UC were 0.65 and 0.74, respectively.When combined FNP with FCP, the AUC in pa-tients with CD and UC were 0.85 and 0.92, respectively. Conclusion FNP is a novel reliable and non-invasive biomarker to evalu-ate clinical disease activity in patients with IBD as accurate as FCP, It is advisable to combine FNP with FCP to evaluate disease activi-ty in patients with IBD.