Retrospective evaluation of the clinical diagnostic value of serologic markers in children with inflammatory bowel disease

Serologic markers play an important role in the diagnosis of inflammatory bowel disease (IBD). Various serum markers of IBD have been actively studied over the last few years, but despite the accumulated experience, an ideal biomarker has not yet been found. In routine clinical practice, antineutrophil cytoplasmic antibodies (ANCA) and antibodies to Saccharomyces cerevisiae (ASCA) are evaluated. Objective. To study the clinical and diagnostic value of ANCA and ASCA in children with IBD. Patients and methods. Data from 663 case histories of 136 children with IBD were retrospectively analyzed: 102 patients with ulcerative colitis (UC) and 34 with Crohn's disease (CD). The PCDAI index was used to assess the clinical activity of CD, and the PUCAI index was used for UC. Endoscopic activity in UC was assessed with the UCEIS index, and in CD with the SES-CD index. ANCA was evaluated as positive at ≥1.0, ASCA IgA and/or IgG at >20 U/mL. Results. ANCA and ASCA were significantly more frequent in the UC and CD groups, respectively (62.7 and 82.4%, p < 0.001). In the UC group, ANCA-positive status correlated with total colonic lesions (p = 0.003) and clinical activity (p = 0.001). ASCApositive status in children with CD correlated neither with the localization of the pathological process, nor with clinical or endoscopic activity. Serologic markers showed to be fairly stable throughout the follow-up period in 76% of UC patients and 85% of CD patients. ANCA-positive children with UC were significantly more likely to have extraintestinal manifestations in the form of lesions of the hepatobiliary system (91% (10/64) vs. 2.5% (2/38), p < 0,001). Conclusion. Despite their widespread use, the clinical significance of serologic biomarkers ANCA and ASCA is not reliably clear; they still remain auxiliary diagnostic tools in the management of patients with IBD. Further studies of serum markers in larger prospective cohort studies are needed. Key words: Crohn's disease, inflammatory bowel disease, children, serologic markers, ulcerative colitis, ANCA, ASCA