A study of urine lactulose/mannitol ratio and intestinal fatty acid binding protein as the indexes of intestinal damage in sepsis

Abstract

To assess urine lactulose/mannitol ratio (LMR), and intestinal fatty acid binding protein (IFABP) concentration as the indexes of intestinal damage in septic patients, and to evaluate the clinical severity and mortality of septic patients by use of these indexes. Thirty-eight patients with sepsis were consecutively selected in Beijing Friendship Hospital intensive care unit (ICU) from June 2007 to February 2008, according to the inclusions and exclusions criteria. Urine samples were taken in 72 hours after ICU admission. Urine LMR was determined by high performance liquid chromatography by use of pulsed electrochemical detection (HPLC-PED), and urine IFABP concentration was determined by enzyme-linked immunosorbent assays (ELISA). The results of LMR and IFABP were analyzed with acute physiology and chronic health evaluation II (APACHE II) score, with multiple organ dysfunction syndrome (MODS) or not and outcome on day 28. The relationship between the two indexes and the patients' gastrointestinal function score was analyzed. Thirty-eight patients included had significantly higher urine level of IFABP concentration and LMR. Urine LMR were higher in patients with APACHE II score > 20 than in patients with APACHE II score < or =20 (P = 0.056), and the values were significantly higher in patients who with MODS and in nonsurvivors than those in patients who without MODS and in survivors (both P < 0.05). Urine IFABP concentration was not found significantly difference in patients with APACHE II score > 20, those with MODS and nonsurvivors, compared with patients with APACHE II score < or = 20, those without MODS and survivors. Patients with stress ulcer had higher urine IFABP concentration than patients without stress ulcer (P < 0.05). There was no correlation among LMR, IFABP and gastrointestinal function score. This study reveals that patients with sepsis have intestinal mucosal damage and increased intestinal permeability. Increased LMR in urine is associated with clinical severity and prognosis; urine IFABP concentration is not associated with clinical severity and prognosis. Patients with stress ulcer have higher urine IFABP concentration. There is no correlation among IFABP, LMR and gastrointestinal function score.