Objective: To describe the prevalence of serological markers in newly diagnosed treatment-naïve pediatric inflammatory bowel disease (IBD), their utility in differentiating Crohn's disease (CD), ulcerative colitis (UC) and symptomatic non-IBD patients and whether serological markers are associated with early TNF blocker treatment.
Material and methods: Ninety-six children and adolescents <18 years, 58 with IBD and 38 symptomatic non-IBD controls were included. At diagnosis and after 1-2 years, serological antibodies (anti-Saccharomyces cerevisiae antibodies (ASCA), perinuclear anti-neutrophil cytoplasmic antibody (pANCA), flagellin expressed by Clostridial phylum (anti-CBir1), outer membrane porin of Escherichia coli (anti-OmpC), Pseudomonas fluorescens-associated sequence (anti-I2), CRP, ESR and fecal calprotectin were analyzed. The choice of treatment was made at the discretion of the treating pediatrician.
Results: Of the IBD patients, 20 (36%) and 26 (47%) were positive for ASCA and pANCA compared to 3(8%), p < .01 and 10 (27%), p = .04 of the controls. Thirteen (72%) of UC patients were pANCA positive, versus 13 (35%) of CD patients (p < .01). None of the UC patients was ASCA positive versus 20 (54%) of CD patients (p < .0001). Compared to conventionally treated patients, the 18 (49%) TNF blocker treated CD patients had higher presence of ASCA (p < .01), lower presence of pANCA (p = .02) and higher levels of fecal calprotectin, CRP and ESR at diagnosis. In multivariate analyses ASCA and pANCA status, but not CRP, ESR or calprotectin, were independently associated with early TNF blocker treatment.
Conclusions: ASCA and pANCA status were associated with having IBD and with early TNF blocker treatment in CD.
Keywords: ASCA; Crohn’s disease; IBD; TNF blocker; biologic therapy; biomarkers; pANCA; pediatric; serological markers; ulcerative colitis.