Correlation of serum biomarkers with clinical severity and mucosal inflammation in Chinese ulcerative colitis patients

Abstract

Serum biomarkers are commonly used for diagnosing and monitoring the disease activity of ulcerative colitis (UC) patients. However, their role in predicting active mucosal inflammation on Chinese patients is unknown. Our aim was to determine the sensitivity and correlation of these biomarkers with clinical severity and mucosal inflammation. Patients who had been newly diagnosed or who had developed a clinical relapse were identified. Active mucosal inflammation was confirmed by colonoscopy and histology. Those patients who had routine serum biomarkers (C-reactive protein [CRP], erythrocyte sedimentation rate [ESR], white cell count, hemoglobin, platelet count and albumin) checked within 14 days of the index colonoscopy were recruited for a retrospective analysis. The disease severity was graded clinically and the positive rate of each marker was determined. The correlation of these markers with the clinical severity and extent of colitis were assessed by the Mann-Whitney U-test or the Kruskal-Wallis test. For the categorical variable, chi(2) or the Fisher's exact test were adopted. From January 2001 to December 2006, 49 Chinese UC patients fulfilled the inclusion criteria. There were 78 acute mucosal inflammatory episodes (24 at diagnosis and 54 clinical relapses). Abnormal CRP, ESR, white cell count, hemoglobin, platelet count and albumin occurred in 42.3%, 55.1%, 23.1%, 21.8%, 32.1% and 25.6% of these mucosal inflammatory episodes, respectively. For the severity of the clinical disease, all serum biomarkers demonstrated a good correlation with the severity grading. On the other hand, the serum biomarkers correlated well with endoscopic extensive colitis but not with proctitis or left-sided colitis. Routine serum biomarkers are not sensitive in predicting mucosal inflammation. However, they are helpful in identifying patients with extensive colitis or clinically severe disease.