Objective To investigate the content of intestinal fatty acid binding protein (IFABP) and its clinical significance in patients with severe sepsis.Methods A prospective observational study was conducted.Fifty patients with severe sepsis admitted to intensive care unit (ICU) of the First Affiliated Hospital of China Medical University from July to December 2012 were enrolled,and 20 healthy patients served as control group.The concentrations of serum IFABP,interleukin-6 (IL-6),and tumor necrosis factor-α (TNF-α) were determined with enzyme-linked immunosorbent assay (ELISA) on days 0,1 and 3 after ICU admission.Acute physiology and chronic health evaluation Ⅱ (APACHE Ⅱ) and sequential organ failure assessment (SOFA) score,28-day prognosis,acute gastrointestinal injury (AGI) grade were recorded at the same time.Furthermore,the contents of IFABP were compared between control group and the severe sepsis group,abdominal infection group and non-abdominal infection group,the survival group and the death group,as well as among different AGI-grade groups.Correlation analysis of IFABP and inflammatory factors,IFABP and two scores,and IFABP and time of stay in ICU and mechanical ventilation were studied.Multivariate logistic regression and analysis of 28-day outcome of the patients were also studied.Results IFABP levels were increased in severe sepsis patients on days 0,1 and 3 compared with those of healthy control group (mg/L:731.90 ±53.91,592.07 ±41.94,511.85 ±47.97 vs.439.88 ±23.68,all P =0.000).There was no statistical significance of IFABP levels between abdominal infection group and non-abdominal infection group,the survival group and the death group,or among different AGI-grade groups.The correlation analysis showed that IFABP was statistically related with IL-6 (r=0.794,P=0.000),TNF-α (r=0.878,P=0.010),APACHE Ⅱ score (r=0.428,P=0.000) in patients with severe sepsis.Significant correlations were also found between IFABP and IL-6 (r=0.812,P=0.000),TNF-α (r=0.885,P=0.000) in abdominal infection group,as well as in non-abdominal infection group (IL-6:r=0.739,P=0.000; TNF-α:r=0.828,P=0.000).As shown by multivariate logistic regression analysis,SOFA scores on days 0,1,3 were the independent risk factors for death [odds ratio (OR) was 1.624 (P=0.004),1.411 (P=0.027),1.740 (P=0.012),respectively],but IFABP level,AGI grade,and APACHE Ⅱ score had no influence on death rate.Conclusion IFABP concentrations in patients with severe sepsis were significantly increased,and it is correlated well to IL-6,TNF-α and APACHE Ⅱ score,but did not related obviously with AGI grade and the prognosis of the patients.