Serum concentrations of insulin-like growth factor-binding protein 5 in Crohn’s disease

AIM:To investigate serum insulin-like growth factorbinding protein 5(IGFBP-5)levels and intestinal IGFBP-5expression in patients with Crohn’s disease(CD).METHODS:We analyzed the serum concentrations and intestinal expression of IGFBP-5 in 42 patients with CD,of whom 26 had endoscopically or radiologically proven stricture formation.Nine of the 42 patients had active disease,with a Crohn’s disease activity index>150.Serum IGFBP-5 levels were analyzed in 20 healthy controls matched by sex and age to the CD patients.Serum IGFBP-5 was measured using an enzyme-linked immunosorbent assay.Intestinal tissue was obtained from patients through endoscopic biopsies.IGFBP-5expression was detected using immunohistochemistry and was scored semiquantitatively.RESULTS:The median serum IGFBP-5 concentrations of CD patients were significantly lower compared with healthy controls[median 7.2(IQR:5.5-11.3)ng/mL vs 11.3(8.0-44.6)ng/mL,P<0.001].There was no significant difference between median serum IGFBP-5levels in CD patients with or without stricture formation[6.9(5.5-11.3)ng/mL vs 7.8(5.3-10.1)ng/mL,P=0.815].The serum IGFBP-5 levels were not significantly different between patients with active disease and inactive disease[7.2(6.5-7.6)ng/mL vs 7.2(5.5-11.3)ng/mL,P=0.890].However,a significant correlation was observed between serum IGFBP-5 levels and platelet count(PLT)(r=0.319,P=0.0395).No significant correlation was found between tissue IGFBP-5 immunohistochemical staining intensity scores and serum IGFBP-5 levels.No significant difference was found when comparing the serum IGFBP-5 levels among the patients with different tissue IGFBP-5 staining scores(absent/very weak,weak,moderate or strong).There was a significant correlation between tissue IGFBP-5staining scores and white blood cell count(r=0.391,P=0.01)and PLT(r=0.356,P=0.021).CONCLUSION:Our results indicate that serum IGFBP-5 concentrations were lower in CD patients compared to healthy controls regardless of disease activity or the presence of stricture formation.